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.

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.

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 507cm³(16.1cm³ to 6961cm³) and decreased to 361cm³(8.7cm³ to 5695cm³) 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.

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.”

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.

Hindquarter amputations for bone or soft tissue sarcoma cause a high degree of disability in patients and are associated with high morbidity rates. The goal of this study is to determine prognostic factors for outcome and analyse quality of life after resection, in order to better select patients who are more likely to benefit from a hindquarter amputation.

Our prospectively collected database was searched for all patients treated with a hindquarter amputation between 1989 and 2015. Clinical and histopathological features were analysed for their prognostic value using Kaplan-Meier and Cox proportional hazard analysis. Endpoints were set at recurrent disease and death. Also, functional and social outcome as well as pain was assessed from the hospital charts in the patients that are still alive.

82 patients underwent a hindquarter resection in the given time frame. Of these patients, 63 were treated with a curative intent. The median hospital stay was 25 days, and 49% of the patients had wound complications. The in-hospital mortality was 6%. The 5-year overall survival in the whole group was 31%, while disease free survival was 26%. As expected, patients with metastases at presentation had a significantly worse outcome, while patients with locally recurrent sarcoma had the same outcome as patients with primary sarcoma. For those patients treated with curative intent, younger age was correlated with better survival, while higher histological grade was correlated with worse disease free survival. The functional and social outcome for patients who survived more then one year varied widely, with about 50% of the patients living an acceptable social life with reasonable pain levels and mobility status.

Hindquarter amputations for sarcoma patients are still indicated for a select group of patients. Younger patients and/or patients with low grade sarcomas are more likely to benefit form this resection in terms of survival and long term function. However, for patients with less favourable prognostic factors a hindquarter operation might be an unreasonable palliative option.

Soft tissue sarcomas (STS) arising in the adductor compartment of the thigh are frequently large before clinical detection, posing particular challenges with surgical resection and associated with a high risk of wound complications. This study compares oncological and functional outcomes and complications following treatment of adductor compartment soft tissue sarcomas from three international centres with different treatment philosophies.

184 patients with new primary, non-metastatic, deep STS in the adductor compartment diagnosed between 1990 and 2001 were identified from the centres' local databases. The Toronto Extremity Salvage Score (TESS) was used to assess function in patients.

There were 94 male and 90 female patients, with ages ranging from 13 to 88 years (median age 57 years). The period of follow-up ranged from 1 to 162 months. The overall survival was 65% at 5 years and related to grade and size of the tumour. There was no difference in overall survival or systemic relapse between the three centres. There was however a significant difference in local control (28% LR in centre 1 compared to 10% in centre 2 and 5% in centre 3, which appeared to be principally related to the use of radiotherapy and surgical margins.)

66 patients (36%) from the three centres developed wound complications post-operatively and it was shown to be associated with high grade and large tumours (>10cm).

Functional scores averaged 78% but were significantly worse for patients with wound complications or high-grade tumours; however, they were not affected by timing of radiotherapy or use of prophylactic free muscle flaps.