Benign aggressive tumors are common and can be debilitating for patients especially if they are in peri-articular regions or cause pathological fracture as is common for giant cell tumor of bone (GCT). Although GCT rarely metastasize, the literature reports many series with high rates of local recurrence, and evidence about which risk factors influence recurrence is lacking. This study aims to evaluate the recurrence rate and identify local recurrence risk factors by reviewing patient data from a single high-volume orthopedic oncology center. A retrospective analysis of all patients treated for GCT at a tertiary orthopedic oncology center was conducted. In total 413 patients were treated for GCT between 1989 and 2017. Multiple patient and tumour characteristics were analysed to determine if they influenced local recurrence including: age, gender, anatomical site, Campanacci stage, soft tissue extension, presence of metastasis, pathologic fractures, and prior local recurrence. Additional variables that were analysed included type of treatment (en bloc resection or aggressive intralesional curettage) and use of local adjuvants. The main outcome parameters were local recurrence- free survival, metastasis-free survival and complications. Patients treated with Denosumab were excluded from analysis given its recently documented association with high rates of local recurrence. “There were 63/413 local recurrences (15.3%) at a mean follow-up of 30.5 months. The metastatic rate was 2.2% at a mean 50.6 months follow-up and did not vary based on type of treatment. Overall complication rate of 14.3% was not related to treatment modality. Local recurrence was higher (p=0.019) following curettage (55/310; 17.7%) compared to resection (8/103; 7.8%) however, joint salvage was possible in 87% of patients (270/310) in the curettage group. Use of adjuvant therapy including liquid nitrogen, peroxide, phenol, water versus none did not show any effect on local recurrence rates (p= 0.104). Pathological fracture did not affect local recurrence rates regardless of treatment modality (p= 0.260). Local recurrence at presentation was present in 16.3% (58/356) patients and did not show any significance for further local recurrence (p= 0.396). Gender was not associated with local recurrence (p=0.508) but younger patient age, below 20 years (p = 0.047) or below 30 years (p = 0.015) was associated with higher local recurrence rates. GCT in distal radius demonstrated the highest rate of local recurrence at 31.6% compared to other sites, although this was not significant (p=0.098). In addition, Campanacci stage and soft tissue extension were not risk factors for recurrence. The overall GCT local recurrence rate was 15.3%, but varied based on the type of resection: 17.7% following joint sparing curettage compared to 7.8% following resection. Local recurrence was also higher with younger patient age (30 years or less) and in distal radius lesions. In addition, neither Campanacci stage, soft tissue extension or presence of a pathologic fracture affected local recurrence. Most patients with GCT can undergo successful curettage and joint sparing, while only a minority require resection +/− prosthetic reconstruction. Even in the presence of soft tissue extension or a pathologic fracture, most joints can be salvaged with curettage

Traditional staging systems for high grade osteosarcoma (Enneking, MSTS) are based largely on gross surgical margins and were developed before the widespread use of neoadjuvant chemotherapy. It is now well known that both microscopic margins and chemotherapy are predictors of local recurrence. However, neither of these variables are used in the traditional surgical staging and the precise safe margin distance is debated. Recently, a novel staging system utilizing a 2mm margin cutoff and incorporating precent necrosis was proposed and demonstrated improved prognostic value for local recurrence free survival (LRFS) when compared to the MSTS staging system. This staging system has not been validated beyond the original patient cohort. We propose to analyze this staging system in a cohort of patients with high-grade osteosarcoma, as well as evaluate the ability of additional variables to predict the risk of local recurrence and overall survival. A retrospective review of a prospectively collected database of all sarcoma patients between 1985 and 2020 at a tertiary sarcoma care center was performed. All patients with high-grade osteosarcoma receiving neo-adjuvant chemotherapy and with no evidence of metastatic disease on presentation were isolated and analyzed. A minimum of two year follow up was used for surviving patients. A total of 225 patients were identified meeting these criteria. Univariate analysis was performed to evaluate variable that were associated with LRFS. Multivariate analysis is used to further analyze factors associated with LRFS on univariate analysis. There were 20 patients (8.9%) who had locally recurrent disease. Five-year LRFS was significantly different for patients with surgical margins 2mm or less (77.6% v. 93.3%; p=0.006) and those with a central tumor location (67.9 v. 94.4; <0.001). A four-tiered staging system using 2mm surgical margins and a percent necrosis of 90% of greater was also a significant predictor of 5-year LRFS (p=0.019) in this cohort. Notably, percent necrosis in isolation was not a predictor of LRFS in this cohort (p=0.875). Tumor size, gender, and type of surgery (amputation v. limb salvage) were also analyzed and not associated with LRFS. The MSTS surgical margin staging system did not significantly stratify groups (0.066). A 2mm surgical margin cutoff was predictive of 5-year LRFS in this cohort of patients with localized high-grade osteosarcoma and a combination of a 2mm margin and percent necrosis outperformed the prognostic value of the traditional MSTS staging system. Utilization of this system may improve the ability of surgeons to stage thier patients. Additional variables may increase the value of this system and further validation is required

Ewing Sarcoma is the second most common primary bone sarcoma in young patients, however, there remains geographical variation in the treatment of these tumours. All patients receive neoadjuvant chemotherapy and, in most cases, the soft tissue mass diminishes significantly in volume. Controversy surrounds whether to then treat the pre- or post-chemotherapy tumour volume. Many centres advocate either (1) resection of the pre-chemotherapy volume or (2) treatment of the pre-chemotherapy volume with radiation followed by resection of the post-chemotherapy volume. These approaches increase both the short and long-term morbidity for this young patient population. In this study, we retrospectively reviewed our experience resecting only the post-chemotherapy volume without the use of (neo)adjuvant radiotherapy. A retrospective analysis of all patients with Ewing Sarcoma treated at a tertiary orthopaedic oncology centre was conducted. All patients were treated as per the consensus opinion of the multidisciplinary tumour board. Demographic and oncological variables were collected from our institutional database. Presentation and re-staging MRI scans were reviewed to evaluate pre- and post-chemotherapy tumour volumes. Operative and pathology reports were utilized to determine the extent of the surgical resection. Outcome variables included local recurrence free-, metastasis free- and overall survival. Sixty-five patients were identified in our institutional database of which 56 did not receive (neo)adjuvant radiotherapy. Median age at diagnosis was 24 years (range 13–64), 60% of patients were male and 67.6% of tumours were located in the appendicular skeleton. All 56 patients not treated with radiotherapy had resection of the post-chemotherapy tumour volume. There were 3 local recurrences in this group with a mean follow-up of 70.8 months (range 2 to 328). The median overall survival was 47 months and the mean of 70.8months. The rate of local recurrence is comparable to reports in the literature in which patients had their entire pre-chemotherapy tumour volume treated by radiation and/or surgery. Similarly, two-year overall survival for our patient cohort is not significantly different from previous studies in which more aggressive local control measures were employed. Resecting the post-chemotherapy tumour volume in Ewing Sarcoma without the use of (neo)adjuvant radiotherapy does not appear to increase the risk of local recurrence or negatively impact overall survival. This approach should be studied further as it reduces the risk of short and long-term complications for this patient population.”

Purpose. The main predictors in the literature of local control for patients operated on for a soft tissue sarcoma are age, local presentation status, depth, grade, size, surgical margins and radiation. However, due to the competing effect of death (patients who die are withdrawn from the risk of local recurrence), the influence of these predictors on the cumulative probabilities may have been misinterpreted so far. The objective of the study was to interpret the influence of known predictors of local recurrence in a competing risks setting. Method. This single center study included 1519 patients operated on for a localized soft tissue sarcoma of the extremity or trunk. Cox models were used to estimate the cause specific hazard of known predictors on local recurrence. Cumulative incidences were estimated in a competing risks scenario. Results. Overall the cumulative probabilities of local recurrence at 2, 5, and 10 years were 5.4% (4.3%–6.7%), 8.2% (6.8%–9.8%), and 11.7% (9.8%–14.3%). The cumulative probabilities of metastasis at 2, 5, and 10 years were 23.3% (21.1%–25.5%), 28.7% (26.2%–31.1%), and 33.7% (30.8%–36.7%). Older age, locally recurrent, high grade and deep tumors, absence of radiation and positive surgical margins were significantly associated with an increased risk of local recurrence. However, when considering competing risks, the cumulative probabilities of local recurrence were significantly different only with presentation status (P < 0.0001), surgical margins (P < 0.0001) and use of adjuvant radiation (P = 0.04). At 10 years, the cumulative probability of local recurrence was 10.6% and 22.6% for patients presenting with a primary or locally recurrent tumor, 9.3% and 23.3% for patients with negative or positive surgical margins, and 9.8% and 16.8% for patients receiving or not receiving radiation respectively. There was no difference in the cumulative probabilities of local recurrence with regard to tumor depth (P = 0.29), size (P = 0.78) or grade (P = 0.29). Patient survival at 2, 5, and 10 years was 85.5% (95% CI: 83.7%–87.4%), 74.6% (95% CI: 72.1%–77.1%), and 64.3% (95% CI: 61%–67.7%). Conclusion. The effect of variables on the cumulative probability of local recurrence should be interpreted in a competing risks setting. Grade and depth are not associated with an increased cumulative probability of local recurrence

Purpose. Mesenchymal stromal cells (MSCs) are an attractive choice for regenerative medicine. We previously showed that MSCs enhance wound healing in animals after radiotherapy. The effect of MSCs on tumor growth is not well understood. The potential use of MSCs to enhance wound healing after radiotherapy (RT) and resection of soft tissue sarcoma (STS) is dependent on a satisfactory safety profile to ensure that tumor proliferation does not occur and recurrence is not increased. Method. Primary cell lines (human myxofibrosarcoma and undifferentiated sarcoma) derived from sarcoma bearing patients and a commercialized human fibrosarcoma cell line (HT1080) were used. Cell line proliferation assay after co-culture with MSCs was done using flow cytometry (CFSE) and bioluminescence emission (BLI) (using eGFP/Fluc transduced cell lines). Five xenograft models were developed with NOD/SCID gc-null mice (n=164) harbouring primary tissue lines obtained from patients biopsies (myxofibrosarcoma and three pleomorphic undifferentiated sarcoma [PUS A, B and C]) and a a fibrosarcoma cell line previously transduced with eGFP/Fluc. Tumors were passaged to three mouse generations before a tissue line was established and the model was then used. For the fibrosarcoma model, eGFP/Fluc HT1080 were injected under the dorsal skin. When tumors reached 1cm in diameter, they received localized RT and 48hr later were resected. MSCs (n=82) or medium alone (n=82) was injected subcutaneously adjacent to the wound after tumor resection. Histological and in vivo BLI analysis were performed 3 and 12 weeks after surgery. Results. In Vitro Proliferation Assay. For the flow cytometric proliferation assay, there was an increase in the doubling time after five days in the myxofibrosarcoma-MSCs co-culture system (140.4h) compared with controls (55.4 h, p<0.001). No significant differences were found in other cells lines. Lower BLI emission was found in co-cultured myxofibrosarcoma cells at the 3rd and 4th day compared with controls (p<0.01 and p<0.05 respectively). In Vivo Recurrence Assay. For mice bearing the fibrosarcoma cell line, in vivo BLI performed 3 weeks after surgery showed similar emission intensity in MSC-treated mice and controls while histological recurrence was significantly lower in MSC-treated animals (40%) than control (72%, p=0.045). For mice bearing the myxofibrosarcoma tissue line, histological recurrence at 12 weeks was similar in MSCs-treated animals and controls (p=0.44). Mice xenografted with pleomorphic undifferentiated sarcoma A and B did not develop local tumor recurrence after histological analysis, while pleomorphic undifferentiated sarcoma C showed similar recurrence in MSC and medium treated mice (p=0.46). Conclusion. We showed that MSCs decrease the proliferation rate of the myxofibrosarcoma cell line in vitro and have no effect, or even decrease, local recurrence of different STS tissue lines in vivo after RT and resection. Clinical investigation of this approach is warranted

The Australia and New Zealand Sarcoma Association established the Sarcoma Guidelines Working Party to develop national guidelines for the management of Sarcoma. We asked whether surgery at a specialised centre improves outcomes. A systematic review was performed of all available evidence pertaining to paediatric or adult patients treated for bone or soft tissue sarcoma at a specialised centre compared with non-specialised centres. Outcomes assessed included local control, limb salvage rate, 30-day and 90-day surgical mortality, and overall survival. Definitive surgical management at a specialised sarcoma centre improves local control as defined by margin negative surgery, local or locoregional recurrence, and local recurrence free survival. Limb conservation rates are higher at specialised centres, due in part to the depth of surgical experience and immediate availability of multidisciplinary and multimodal therapy. A statistically significant correlation did not exist for 30-day and 90-day mortality between specialised centres and non-specialised centres. The literature is consistent with improved survival when definitive surgical treatment is performed at a specialised sarcoma centre. Evidence-based recommendation: Patients with suspected sarcoma to be referred to a specialised sarcoma centre for surgical management to reduce the risk of local recurrence, surgical complication, and to improve limb conservation and survival. Practice point: Patients with suspected sarcoma should be referred to a specialised sarcoma centre early for management including planned biopsy

Myxoid or Myxoid Round Cell liposarcoma (MLS) is a mesenchymal malignancy with adipocyte differentiation accounting for 15–20% of liposarcomas and 5% of all adult soft tissue sarcomas (STS). Like other STS, treatment of MLS is generally by wide surgical resection in conjunction with radiotherapy and this approach is associated with low rates of local recurrence [1]. However, most MLS are located between muscles so wide local excision(WLE) can be quite morbid with adverse functional results. MLS are known to be extremely sensitive to radiotherapy which has led to development of treatment protocols utilizing neoadjuvant radiation. Given the radiosensitivity of MLS, we hypothesize that resection with marginal margins (1mm) does not result in higher rates of local recurrence or disease-free survival if performed following pre-operative radiotherapy. We identified all patients with localized MLS who underwent preoperative radiation and surgical resection between January 2000 and January 2018 from a prospectively collected sarcoma database. We calculated the ellipsoid tumour volume(ETV=h x w x d x ()) at diagnosis and after radiation, and documented the necrosis percentage of the tumour and margin status following resection based on histological analysis [2]. Marginal resection was identified by the operative report describing no or only very minimal resection of muscle surrounding the tumour, and a negative surgical margin 0.1cm/1mm as defined histologically. In comparison, WLE was defined if the operative note described an attempt to remove the tumour with a cuff of surrounding muscle, and the final histology reported a negative margin 0.1cm/1mm which included skeletal muscle. The third group for analysis included patients with positive resection margins. There were 91 patients with MLS of mean age 48 years (range 18–88) with 69% male and 31% female. The mean pre-radiotherapy ETV was 507cm. 3. (16.1cm. 3. to 6961cm. 3. ) and decreased to 361cm. 3. (8.7cm. 3. to 5695cm. 3. ) following radiation, with an average percentage reduction in ETV of −45%(+129%to-99%). Mean patient follow-up was 7.3 years (0.2–18) with no differences between margin groups(p=0.284). Only 10(11%) patients had positive margins, of which 43(47%) underwent marginal resection and 38(42%) WLE. Overall the mean necrosis as measured histologically following preoperative radiation was 69% (range 0–100%) with no differences between the 3 resection groups(p-0.151). Similarly, there was no significant difference in reduction in mean ETV between the three resection groups(p=0.311), there was no significant difference between the three treatment groups in 5-year LR-free survival (p=0.469), metastasis-free survival (p=0.841) or overall survival (p=0.873). Most patients with MLS experienced significant reduction in tumour size and necrosis following preoperative radiation. We found no differences in the risk of local recurrence or survival based on the type of surgical approach for patients with MLS. Based on these results, we conclude that MLS can be safely removed by marginal resection following preoperative radiotherapy with high rates of local tumour control. Even following a positive margin resection, local recurrence remains uncommon after preoperative radiation. A marginal surgical approach for patients with MLS reduces the need for major muscle resection and is associated with improved functional outcomes with less complications

Dermatofibrosarcoma protuberans (DFSP) is a rare, monoclonal dermal neoplasm. DFSP is known to be locally aggressive and infiltrative, but with a very low systemic recurrence risk. It is reported to be associated with high local recurrence rates following surgical excision. Positive or marginal resection margins can lead to a high risk of local recurrence. The objective was to determine the oncologic outcome for DFSP treated at our institution. We reviewed our prospectively collected database for all DFSP treated at our unit between 1990 and 2016. Patients were included whether or not they had excision prior to referral (“whoops” procedure). Those with fibrosarcomatous degeneration at presentation to our unit or less than 1 year of follow-up were excluded. The goal of surgery was a negative margin with a minimum margin of 2 cm where possible. Patients were followed up after surgery to monitor complications, recurrence, transformation and/or metastasis. 139 patients with a mean age of 42.7 (SD=14.1) were included. Mean follow-up was 56 months.101 patients had prior “whoops” surgery before referral. 14 patients were also treated with radiotherapy (13 preoperatively, 1 postoperatively). Following surgery, 6 patients had positive margins, 4 underwent radiation treatment while the other 2 had no further treatment. One patient who presented to our unit with a local recurrence developed a further local recurrence, which demonstrated fibrosarcomatous degeneration at the time of resection (1/139, 0.7%). 1 other patient developed a lesion at another site. The recurrence rate in our DFSP cohort is significantly lower than previous reports. Wide margin resection following oncologic principles can result in a very low recurrence rate. After the initial recovery phase, these patients do not require ongoing, frequent follow-up. Future studies should look at if closer margins can also produce similar treatment outcome

Abstract. Background. Reconstruction following resection of sarcomas of the upper extremity with methods described in the prevalent literature may not be possible in few selected cases. We describe Surgical Phocomelia or Phoco-reduction as a method of limb salvage in such cases of extensive sarcomas of the upper limb with its functional and oncological outcomes. Methods. Evaluation of functional and oncological outcomes was performed for 11 patients who underwent surgical phocomelia or phocoreduction for extensive sarcomas of the upper limb between 2010 and 2019. Results. Mean follow-up period in the study was27.8 months. Five patients required a segmental resection including the entire humerus while 6 patients underwent segmental resection around the elbow with a mean resection length of 21.5 cm. Mean MSTS 93 score was 22 depicting a good functional outcome. Mean hand grip strength on the operated side was 62% of the contralateral side with preservation of useful hand function. Mean time to humero-ulnar union was 6.7 months. Radial nerve palsy and implant failure occurred in 1 patient each. No patient developed local recurrence while 3 patients died of metastasis. Conclusion. Surgical phocomelia is a prudent alternative to severely incapacitating amputations in situations where other reconstruction methods are not feasible

Solitary fibrous tumor (SFT) is a rare mesenchymal tumor with an intermediate tendency to metastasize, which is found in many different locations including head and neck, abdomen, chest cavity and extremities. Also, meningeal hemangiopericytoma (HPC) is considered an SFT which arises in the meningeal membranes. SFT family shows an undetermined biologic behavior varying from a silent indolent tumor to an aggressive malignant form; however, benign and malignant variants of SFT may have similar cytopathologic characteristics. In this study, we defined the factors correlated with SFT's aggressive behavior and patient's survival. This is a retrospective study based on medical records of 85 patients who were suffering from SFT and had been treated at McGill University Health Centre (MUHC) between 1984 and 2017. We used multivariate logistic regression analysis to address any association between the variables including patient's demographics, tumor size, primary location of the tumor, pathological features, treatment methods and outcomes. The median of the follow-up period was 60 months. The patient's age or gender had no association with tumor aggressive behavior or patient's survival. Anatomical origin of primary tumor had no strong correlation with the patient's disease related death (DRD); however, tumors originated from CNS showed more aggressive behavior. There was an association between tumor size more than 7 cm and distant metastasis (MT) (p= 0.03) and DRD (p=0.03). The tumor size also correlated with the 5-year disease-free survival (p=0.017). We had three histologic groups: 1- Benign SFT (30 cases), 2- cellular SFT or HPC (29 cases), 3- malignant SFT or anaplastic HPC (26 cases). Although univariate analysis demonstrates that patients suffering from cellular SFT and malignant SFT showed increased aggressive behavior of the tumor, multivariate analysis didn't verify the mentioned association. Patients with positive margins had increased odds ratio to experience tumor local recurrence (LR) (p= 0.05) and LR was correlated with DRD in our patients (p=0.006). Radiotherapy had no statistical association with LR, MT or DRD. Frequency of LR and MT in the study were 25.7% and 29.8% respectively. 5-year disease-free survival in our patients was 76%. The size of SFT is the most correlative predictor of the tumor's aggressive behavior. The local recurrence of SFT is associated with disease related death; therefore, resection of the tumor with negative margins provides the highest chance of cure. In addition, a cellular SFT should be treated like a malignant variant of the tumor

The NZ Standards of Service Provision for Sarcoma patients were developed by the NZ Sarcoma working group and published by the Ministry of Health (MOH) in 2013. Although not formally enacted by the MOH we aimed to determine the impact of these published standards and referral pathways on disease-specific survival of patients with soft-tissue sarcoma in NZ. The Middlemore Musculoskeletal Tumour Unit database was searched. Patients referred for treatment in our centre with a diagnosis of soft tissue sarcoma in the five-year period before (n=115) and after (n=155) were included. We excluded patients with bone sarcomas and retroperitoneal soft tissue sarcomas. The rate of referral after inappropriate treatment reduced after implementation of the Standards (24% vs 12%, p=0.010). The number of patients referred with tumours larger than 50mm decreased (74.8% vs 72.3%, p=0.021) and fewer had metastases at diagnosis (11.3% vs 3.2%, p=0.017). Mortality was lower in the group after introduction of the Standards (45% vs 30%, p=0.017). The estimated disease-specific survival curve between the two groups shows a trend towards increased survival in the post-standards group, although not reaching statistical significance. Local recurrence rate and metastasis rate after definitive treatment were similar between the two groups. Patients had a shorter duration of symptoms before referral in the post-Standards group although this was not statistically significant. Since implementation of the Standards, patients have been referred more promptly, with fewer inappropriate treatments. The time to mortality curve indicates a trend towards improved disease-specific survival. We conclude that the pathway for investigation and referral for this condition has become clearer, supporting the ongoing use of the Sarcoma Standards, and that these should be formally implemented by the MOH

Paediatric bone sarcomas around the knee are often amenable to either endoprosthetic reconstruction or rotationplasty. Cosmesis and durability dramatically distinguish these two options, although patient-reported functional satisfaction has been similar among survivors. However, the impact on oncological and surgical outcomes for these approaches has not been directly compared. We retrospectively reviewed all wide resections for bone sarcoma of the distal femur or proximal tibia that were reconstructed either with an endoprosthesis or by rotationplasty at our institution between June 2004 and December 2014 with a minimum two year follow-up. Pertinent demographic information, surgical and oncological outcomes were reviewed. Survival analysis was performed using the Kaplan-Meier method with statistical significance set at p<0.05. Thirty eight patients with primary sarcomas around the knee underwent wide resection and either endoprosthetic reconstruction (n=19) or rotationplasty (n=19). Groups were comparable in terms of demographic parameters and systemic tumour burden at presentation. We found that selection of endoprosthetic reconstruction versus rotationplasty did not impact overall survival for the entire patient cohort but was significant in subgroup analysis. Two-year overall survival was 86.7% and 85.6% in the endoprosthesis and rotationplasty groups, respectively (p=0.33). When only patients with greater than 90% chemotherapy-induced necrosis were considered, overall survival was significantly better in the rotationplasty versus endoprosthesis groups (100% vs. 72.9% at two years, p=0.013). Similarly, while event-free survival was not affected by reconstruction method (60.2% vs. 73.3% at two years for endoprosthesis vs rotationplasty, p=0.27), there was a trend towards lower local recurrence in rotationplasty patients (p=0.07). When surgical outcomes were considered, a higher complication rate was seen in patients that received an endoprosthesis compared to those who underwent rotationplasty. Including all reasons for re-operation, 78.9% (n=15) of the endoprosthesis patients required a minimum of one additional surgery compared with only 26.3% (n=5) among rotationplasty patients (p=0.003). The most common reasons for re-operation in endoprosthesis patients were wound breakdown/infection (n=6), limb length discrepancy (n=6) and periprosthetic fracture (n=2). Excluding limb length equalisation procedures, the average time to re-operation in this patient population was 5.6 months (range 1 week to 23 months). Similarly, the most common reason for a secondary procedure in rotationplasty patients was wound breakdown/infection, although only two patients experienced this complication. Average time to re-operation in this group was 23.8 months (range 5 to 49 months). Endoprosthetic reconstruction and rotationplasty are both viable limb-salvage options following wide resection of high-grade bony sarcomas located around the knee in the paediatric population. Endoprosthetic reconstruction is associated with a higher complication rate and may negatively impact local recurrence. Study of a larger number of patients is needed to determine whether the reconstructive choice affects survival

Myxofibrosarcoma (MFS) is the second most common subtype of soft tissue sarcoma (STS) and is associated with a high rate of local recurrence after resection. These tumours frequently present with peri-lesional edema, termed “tumour tails” on staging MRI scans [1]. Tumour tails(TT) may contain satellite neoplastic cells or can represent benign reactive edema. There are no clear radiological features to distinguish malignant from reactive peri-lesional edema which limits accurate surgical planning, resulting in either high rates of inadvertently positive resection margins and local recurrences or overly-aggressive resections which negatively impact function and increase morbidity [2]. The objective of this pilot study was to prospectively study a cohort of MFS patients with TTs in an attempt to identify radiological features that predict which type of edema is malignant and requires resection together with the main tumour mass. Patients diagnosed with MFS on biopsy at an orthopaedic oncology referral centre between January 1-December 31 2018 who also had TTs on staging MRI scans were prospectively recruited for the study. Tumours were treated with wide surgical excision, including the TTs, and (neo)adjuvant radiotherapy as per institutional protocol. Staging MRI scans were reviewed in a blinded fashion by two musculoskeletal radiologists to distinguish malignant from reactive TTs. The main tumour mass underwent standard histological evaluation while the regions encompassing the TTs were photographed and sectioned into grids. Each tissue section was examined histologically for the presence of satellite neoplastic cells based on morphological criteria. Radiological and histological findings were compared. Six patients met the inclusion criteria and underwent analysis. All tumours were located in the extremities and were deep to fascia. Mean age at presentation was 67 years (range 51 – 85), with a male:female ratio of 4:2. All patients received radiotherapy (50 Gy), either pre- (n=4) or post-operatively (n=2) based on multidisciplinary tumor board discussion or enrolment in a prospective clinical trial. Radiologically, TTs were labelled as malignant in four patients (66.7%) and as benign TTs in two others. The tails were recognised to be malignant due to the differing signal characteristics to reactive edema on mixed MRI sequences. The radiological evaluation correlated exactly with histological analysis, as satellite neoplastic cells were identified microscopically in the same four cases in which the TTs were designated to be malignant by MRI (specificity&sensitivity=100%). Surgical resection margins were microscopically positive in 50% of cases in the TTs themselves, and 75% of cases in which TTs were designated as malignant on staging MRI. “The malignant nature of peri-lesional edema in MFS, also known as the TT, was accurately predicted in this small pilot study based on specific radiological features which correlated exactly with histologic identification of isolated tumor cells. These findings validate development of a larger prospective study to recruit additional patients with tumor tails beyond just MFS, in order to more robustly study the correlation between the MRI appearance and histological distribution of satellite sarcoma cells in peri-lesional edema in STS. We are already recruiting to this expanded radiological-histological investigation including evaluation of additional novel MRI sequences

INTRODUCTION. Bone tumour resection and subsequent reconstruction remains challenging for the surgeon. Obtaining adequate margins is mandatory to decrease the risk of local recurrence. Improving surgical margins quality without excessive resection, reducing surgical time and increasing the quality of the reconstruction are the main goals of today's research in bone tumour surgical management. With the outstanding improvements in imaging and computerised planning, it is now a standard. However, surgical accuracy is essential in orthopaedic oncologic surgery (Grimmer 2005). Patient specific instruments (PSI) may greatly improve the surgeon's ability to achieve the targeted resection. Thanks to its physical support, PSI can physically guide the blade yielding to a better control over the cutting process (Wong, 2014). Surgical time might significantly be reduced as well when compared to conventional method or navigated procedure. Finally, reconstruction may gain in rapidity and quality especially when allograft is the preferred solution as PSI can be designed as well for allograft cutting (Bellanova, 2013). Since 2011, PSI have systematically been used in our institution for bone tumour resection and when applicable allograft reconstruction. This paper reports the mid- to long-term medical outcomes on a large series. MATERIALS AND METHODS. Between 2011 and 2016, we systematically used PSI to remove bone tumours in 30 patients. The pre-operative planning involved the tumour delineation drawn on MRI by the surgeon. The MRI and obtained tumour volume were transferred to the CT-scan by image fusion (co- registration). Cutting planes were positioned around the tumour including a safe margin. The PSI were designed to ensure a sufficient stability but kept thin enough to limit the bone exposure. The PSI was manufactured by 3D-printing in a biocompatible and sterilisable material. PSI has been intraoperatively to cut the bone with predetermined margins. Medical files were reviewed for large data collection: type, size and site of the tumour, pre-and post-operative metastatic status, bone and soft tissues resection margins, local recurrence, use of an allograft and a PSI for graft adjustment or not for the reconstruction, the fusion of the allograft when applicable, the follow-up time and early/late complications. RESULTS. Over a period of 5 years, 30 patients were operated on with PSI (10 osteosarcomas, 4 chondrosarcomas, 10 Ewing sarcomas and 6 other types of bone tumours). Mean follow-up was 27±20 months. 18 cases out of 30 have more than 2 years follow-up and 13 out of 30 have more than 3 years of follow-up. Mean operating time was 6h02±3h44. Mean size of the tumours was 8,4±4,7cm and location was the upper limb in 5 cases, inferior limb in 15 cases and the pelvis in 10 occurrences. Metastatic disease developed postoperatively in 5 patients. Surgical margins in the bone were R0 in all cases but one case where a R1 surgery was planned to preserve a nerve root. We did not observe any local recurrence in the bone. Within soft tissues, margins were classified as R0 in 28 patients and R1 in 2 patients. In 26 cases, an allograft was used to reconstruct the bone defect. In 23 of those patients, the allograft was selected by CT scan and cut using a PSI. In the 3 allografts cut free-handily, only one demonstrated a fusion. Of the 23 cut with a guide, 12 fused completely, 2 demonstrated a partial fusion and 9 were not fused at the last follow-up. At the last follow-up, 2 patients were dead of disease, 5 were alive with metastatic disease and 23 were alive without disease. DISCUSSION. Oncology is probably the field where PSI can bring the largest advantage when compared to the conventional procedure. Several papers have reported the use of PSI for bone tumour resection. All of them have shown very promising results on in-vitro experiments (Cartiaux 2014), cadaver experiment (Wong 2012) or small clinical series (Bellanova 2013, Gouin, 2014). None of these papers report a large patient series associated with a clinically relevant follow-up. This series is the first mid- to long-term follow-up series involving PSI tumour surgery. These results are showing strong evidences of clinical improvements. It comes into contradiction with PSI for total knee arthroplasty where controversial results on the patient's outcome has been reported (Thienpont 2014). R0 margin has been systematically obtained for all bone cuttings, and local recurrence has been strongly decreased (3%) when compared to the usual recurrence rates published in the literature (from 15% to 35% according to the location). Allograft fusion seems improved as well thanks to the shape-matching of the selected allograft and a close contact between host and allograft at bony junctions. With a longer follow-up, these evidences should be stronger to definitely make PSI the best option for bone tumour resection

Purpose. Due to the aging population, an increasing proportion of elderly patients with soft tissue sarcoma are presenting to cancer centers. This population appears to have a worse prognosis but the reasons for this has not been studied in depth. The purpose of this study is to examine the effect of age on the outcome of patients with extremity and trunk soft tissue sarcoma. Method. This is a multicenter study including 2071 patients with median age at operation of 57 years (1st quartile–3rd quartile: 42–70). The endpoints considered were local recurrence and metastasis with death as a competing event. Cox proportional hazards models were used to estimate hazard ratios across the age ranges with and without adjustment for known confounding factors. Results. Older patients presented with tumors that were larger and of higher grade. The proportion of positive margins increased progressively as patients aged, but radiation therapy was relatively underused in patients over 60 years old. Age was strongly associated with both local recurrence and metastasis. The 5-year cumulative incidences of local recurrence were 7.6% (4.2%–12.2%) for patients 30 years or younger and 13.8% (9.8%–18.5%) for patients 75 years and older; corresponding 5-year cumulative incidences of metastasis were 21.5% (15.7%–28%) and 32.5% (27%–38.2%) for the same groups. Age showed a non linear effect with a dramatic increase in the risk of local recurrence and metastasis after 60 years old. The increased risk of metastasis for older patients was explained by disparities in tumor characteristics at presentation, and additionally for local recurrence, by disparities in treatment. Conclusion. Age is associated with worse outcomes after resection of soft tissue sarcoma. Older patients have worse outcomes because they tend to present with tumors having more adverse prognostic features and they are also treated less aggressively. A significant effect of age that is not explained by known confounders remains

Background. Although soft tissue sarcoma (STS) is a rare malignancy, myxofibrosarcoma is a common form diagnosed. Myxofibrosarcoma is complicated by a high local recurrence rate (18–54%) and significant morbidity following treatment, hence management can be challenging. Patients and Methods. Patients treated between 2003–2012 were identified via a database within the histopathology department and case notes were retrospectively assessed. All histology samples were reviewed by a senior histopathologist to ensure a correct diagnosis. Results. 29 patients (12 male, 17 female) with an average age of 61 years (range 19–89 years) underwent surgery at a single centre, with 24 patients receiving adjuvant and two receiving neo-adjuvant radiotherapy. 22 patients had lower limb and 7 had upper limb tumours. 3 were treated for secondary recurrence after having primary surgery elsewhere. 21 patients had Trojani Grade 2 or 3 tumours. All underwent limb-sparing surgery initially but six patients (20.7%) suffered local recurrence after an average follow-up of 28 months and all ultimately required above knee amputation. Four patients developed wound infection, with one requiring VAC therapy. One patient required a flap repair of the forearm. 5-year survival rate was 87.5%. Conclusions. Our results compare favourably against results published so far in the literature with a low local recurrence rate and mortality. Limb-sparing surgery aims to reduce morbidity and disability following treatment but more research is required in adjuvant treatments to further reduce the risk of local recurrence of tumour

Biological reconstruction techniques after diaphyseal tumour resection have increased in popularity in recent years. High complication and failure rates have been reported with intercalary allografts, with recent studies questioning their role in limb-salvage surgery. We developed a technique in which large segment allografts are augmented with intramedullary cement and fixed using compression plating. The goal of this study was to evaluate the survivorship, complications and functional outcomes of these intercalary reconstructions. Forty-two patients who had reconstruction with an intercalary allograft following tumour resection between 1989 and 2010 were identified from our prospectively collected database. Allograft survival, local recurrence-free, disease-free and overall survival were assessed using the Kaplan-Meier method. Patient function was assessed using the Musculoskeletal Tumour Society (MSTS) scoring system and the Toronto Extremity Salvage Score (TESS). The 23 women and 19 men had a mean age of 33 years (14–77). The most common diagnoses were osteosarcoma (n=16) and chondrosarcoma (n=9). There were 9 humerus, 18 femur and 15 tibia reconstructions. At a mean follow-up of 95 months (5–288), 31 patients were alive without disease, 10 were dead of disease and 1 was deceased of other causes. There were 4 local recurrences and 11 patients developed metastatic disease. 5-year local recurrence free survival was 92%, 5-year disease-free survival was 70% and overall survival was 75%. Fourteen of 42 patients (33%) experienced complications: 5 wound healing complications, 4 infections, 2 non-unions, 2 fractures and 1 nerve palsy. Four allografts (9.5%) were revised for complications and 2 (5%) for local recurrence. Mean allograft survival was 85 months (4–288). Mean time to union was 8.2 (3–36) months for the proximal osteotomy site and 8.1 (3–23) months for the distal osteotomy site. The mean score for MSTS 87 was 29.4 (+/− 4.4), MSTS 93 was 83.7 (+/−14.8) and TESS was 81.6 (+/−16.9). An intercalary allograft augmented with intramedullary cement and compression plate fixation provides a reliable and durable method of reconstruction after tumour resection. Complication rates are comparable to the literature and are associated with high levels of patient function and satisfaction

Low grade chondrosarcoma is currently followed up with the same schedule as all other chondrosarcoma patients. When treated adequately, low grade chondrosarcoma appears to have a very benign follow up course. Patients and Methods:. A retrospective study of follow ups was done on fifty six patients treated for chondrosarcoma at the Pretoria musculoskeletal tumour unit from 1987–2009, evaluating the outcome and presence of local recurrence. The lesions were divided into four histological grades; atypical enchondroma (grade 0), low grade chondrosarcoma (grade 1), intermediate grade chondrosarcoma (grade 2), and high grade chondrosarcoma (grade3). Results:. Biopsy revealed forty-six patients with low grade chondrosarcoma (82%), nine cases of grade 2 chondrosarcoma (16%), and one patient with a metastatic mesenchymal chondrosarcoma. The femur and humerus were the commonest sites involved, while the axial skeleton was only affected in three cases, all of whom had more aggressive lesions. Forty-nine patients had no recurrence after a mean period of 57.5 months follow up. Forty- two of those had low grade lesions, and seven patients had grade 2 lesions. Two patients with low grade lesions were lost to follow up. Three patients involved in the study presented with local recurrence, but no metastases were detected radiographically. Two patients died, one with metastatic mesenchymal chondrosarcoma involving the scapula, and the other with a grade 2 lesion of the pelvis. Conclusion:. We believe that adequately treated low grade chondrosarcomas have a very low local recurrence rate. When faced with recurrence, it rarely presents with distant metastases. A revised schedule of visits at 3 and 6 months followed by yearly visits for five years appears to be adequate for timely detection and treatment of any local recurrence

Introduction. Sacro-coccygeal chordomas pose a difficult diagnostic and therapeutic problem due to late presentation, large size, soft-tisue extension, difficulties in obtaining adequate resection margins, higher local recurrence rate and uncertain effectiveness of adjuvant treatment. We present a series of 21 patients of sacral chordomas obtained from Scottish Bone Tumour Registry to analyse predictors of local control and survival. Patients and methods. The clinical and morphologic features, type of treatment and follow-up of 21 consecutive patients with sacral chordoma were retrospectively reviewed and analysed. Results. The average age at time of the biopsy was 59 years (range, 12 to 82 years): twelve patients were male and nine were female. Pain was the presenting symptom in all patients. Two had intralesional (both recurred), 9 marginal (4 recurred) and 3 wide resections (1 recurred). Fifteen of the twenty-one patients were treated with adjuvant radiation therapy. In seven patients, the chordoma was inoperable and all but one were treated with adjuvant radiotherapy. Local recurrence and metastases occurred in 7 (50%) and 5 (23.8%) patients. The 5-year and 10-year survival were 38% and 14.2%, respectively. Conclusion. Excision of the lesion combined with adjuvant radiation therapy provided satisfactory results. Local recurrence presents a major problem in the management of sacral chordomas (50%). Intralesional resection should be avoided as it is associated with 100% local recurrence in our series

Navigation-assisted surgery has been reported to enhance resection accuracy in bone sarcoma surgery. Patient-specific instruments (PSIs) have been proposed as a simpler alternative with fewer setup facilities. We investigated the use of 3D surgical planning and PSI in realising computer planning of complex resections in bone sarcoma patients with regards to surgical accuracy, problems, and early clinical results. We retrospectively studied twelve patients with bone sarcoma treated surgically by PSIs with 3D planning. The procedure was planned using engineering software. The resection accuracy was accessed by comparing CT images of tumour specimens with the planned in seven patients. Mean age was 30.9 (9 – 64). Mean follow-up was 3.1 year (0.5 – 5.3). 31 planes of bone resections were successfully performed using the technique and were considered accurate. The mean time required for placing PSIs was 5.7 minutes (1 – 10) and performing bone osteotomies with the assistance of PSIs was 4.7 minutes (2 – 7). The mean maximum deviation error was 1.7mm (0.5 – 4.4). One PSI was broken during bone resection, and one patient needed re-resection using the same PSI. One pelvic patient died of local recurrence and lung metastases six months postoperatively. One patient developed a soft tissue local recurrence and lung metastasis at 20 months after surgery. The mean MSTS functional score was 27.9 (21 – 30). There were no complications related to 3D planning and PSIs. In selected patients, 3D surgical planning and PSIs replicate complex bone resections and reconstructions in bone sarcoma surgery. Comparative studies with conventional or navigation- assisted resections are required