Aims. Limb salvage in bone tumour patients replaces the bone with massive segmental prostheses where achieving bone integration at the shoulder of the implant through extracortical bone growth has been shown to prevent loosening. This study investigates the effect of multidrug chemotherapy on extracortical bone growth and early radiological signs of aseptic loosening in patients with massive distal femoral prostheses. Methods. A retrospective radiological analysis was performed on adult patients with distal femoral arthroplasties. In all, 16 patients were included in the chemotherapy group with 18 patients in the non-chemotherapy control group. Annual radiographs were analyzed for three years postoperatively. Dimensions of the bony pedicle, osseointegration of the hydroxyapatite (HA) collar surface, bone resorption at the implant shoulder, and radiolucent line (RLL) formation around the cemented component were analyzed. Results. A greater RLL score (p = 0.041) was observed at three years postoperatively, with those receiving chemotherapy showing greater radiological loosening compared with those not receiving chemotherapy. Chemotherapy patients experience osteolysis at the shoulder of the ingrowth collar over time (p < 0.001) compared with non-chemotherapy patients where osteolysis was not observed. A greater median percentage integration of the collar surface was observed in the non-chemotherapy group (8.6%, interquartile range (IQR) 0.0% to 37.9%; p = 0.021) at three years. Bone growth around the collar was observed in both groups, and no statistical difference in amount of extracortical bony bridging was seen. Conclusion. Multidrug chemotherapy affects the osseointegration of ingrowth collars and accelerates signs of radiological loosening. This may increase the risk of aseptic loosening in patients with massive segmental implants used to treat bone cancer. Cite this article: Bone Joint Res 2020;9(7):333–340

Total joint replacement (TJR) was one of the most revolutionary breakthroughs in joint surgery. The majority studies had shown that most implants could last about 25 years, anyway, there is still variation in the longevity of implants. In US, for all the hip revisions from 2012 to 2017 in the United States, 12.0% of the patients were diagnosed as aseptic loosening. Variable studies have showed that any factor that could cause a systemic or partial bone loss, might be the risk of periprosthetic osteolysis and aseptic loosening. Breast cancer is the most frequent malignancy in women, more than 2.1 million women were newly diagnosed with breast cancer, 626,679 women with breast cancer died in 2018. It's been reported that the mean incidence of THA was 0.29% for medicare population with breast cancer in USA, of which the incidence was 3.46% in Norwegian. However, the effects of breast cancer chemotherapy and hormonotherapy, such as aromatase inhibitors (AI), significantly increased the risk of osteoporosis, and had been proved to become a great threat to hip implants survival. In this case, a 46-year-old female undertook chemotherapy and hormonotherapy of breast cancer 3 years after her primary THA, was diagnosed with aseptic loosening of the hip prosthesis. Her treatment was summarized and analyzed. Breast cancer chemotherapy and hormonotherapy might be a threat to the stability of THA prosthesis. More attention should be paid when a THA paitent occurred with breast cancer. More studies about the effect of breast cancer treatments on skeleton are required

Aims. The aim of this study was to report the long-term prognosis of patients with multiple Langerhans cell histiocytosis (LCH) involving the spine, and to analyze the risk factors for progression-free survival (PFS). Methods. We included 28 patients with multiple LCH involving the spine treated between January 2009 and August 2021. Kaplan-Meier methods were applied to estimate overall survival (OS) and PFS. Univariate Cox regression analysis was used to identify variables associated with PFS. Results. Patients with multiple LCH involving the spine accounted for 15.4% (28/182 cases) of all cases of spinal LCH: their lesions primarily involved the thoracic and lumbar spines. The most common symptom was pain, followed by neurological dysfunction. All patients presented with osteolytic bone destruction, and 23 cases were accompanied by a paravertebral soft-tissue mass. The incidence of vertebra plana was low, whereas the oversleeve-like sign was a more common finding. The alkaline phosphatase was significantly higher in patients with single-system multifocal bone LCH than in patients with multisystem LCH. At final follow-up, one patient had been lost to follow-up, two patients had died, three patients had local recurrence, six patients had distant involvement, and 17 patients were alive with disease. The median PFS and OS were 50.5 months (interquartile range (IQR) 23.5 to 63.1) and 60.5 months (IQR 38.0 to 73.3), respectively. Stage (hazard ratio (HR) 4.324; p < 0.001) and chemotherapy (HR 0.203; p < 0.001) were prognostic factors for PFS. Conclusion. Pain is primarily due to segmental instability of the spine from its destruction by LCH. Chemotherapy can significantly improve PFS, and radiotherapy has achieved good results in local control. The LCH lesions in some patients will continue to progress. It may initially appear as an isolated or single-system LCH, but will gradually involve multiple sites or systems. Therefore, long-term follow-up and timely intervention are important for patients with spinal LCH. Cite this article: Bone Joint J 2023;105-B(6):679–687

We studied the safety of external fixation during post-operative chemotherapy in 28 patients who had undergone distraction osteogenesis (17, group A) or vascularised fibular grafting (11, group B) after resection of a tumour. Four cycles of multi-agent post-operative chemotherapy were administered over a mean period of 14 weeks (6 to 27). The mean duration of external fixation for all patients was 350 days (91 to 828). In total 204 wires and 240 half pins were used. During the period of post-operative chemotherapy, 14 patients (11 in group A, 3 in group B) developed wire- and pin-track infection. A total of ten wires (4.9%) and 11 half pins (4.6%) became infected. Seven of the ten infected wires were in periarticular locations. External fixation during post-operative chemotherapy was used safely and successfully for fixation of a vascularised fibular graft and distraction osteogenesis in 27 of 28 patients. Post-operative chemotherapy for malignant bone tumours did not adversely affect the ability to achieve union or cause hypertrophy of the vascularised fibular graft and had a minimal effect on distraction osteogenesis. Only one patient developed osteomyelitis which required further surgery

Aims. To assess the correlation between the histological response to preoperative chemotherapy and event-free survival (EFS) or overall survival (OS) in patients with high-grade localized osteosarcoma. Methods. Out of 625 patients aged ≤ 40 years treated for primary high-grade osteosarcoma between 1997 and 2016, 232 patients without clinically detectable metastases at the time of diagnosis and treated with preoperative high-dose methotrexate, adriamycin and cisplatin (MAP) chemotherapy and surgery were included. Associations of chemotherapy-induced necrosis in the resected specimen and EFS or OS were assessed using Cox model and the Pearson’s correlation coefficients (r). Time-dependent receiver operating characteristic analysis was applied to determine the optimal cut-off value of chemotherapy-induced necrosis for EFS and OS. Results. OS was 74% (95% confidence interval (CI) 67 to 79) at five years. Median chemotherapy-induced necrosis was 85% (interquartile range (IQR) 50% to 97%). In multivariate Cox model, chemotherapy-induced necrosis was significantly associated with EFS and OS (hazard ratio (HR) = 0.99 (95% CI 0.98 to 0.99); p < 0.001 and HR = 0.98 (95% CI 0.97 to 0.99); p < 0.001, respectively). Positive correlation was observed between chemotherapy-induced necrosis and five-year EFS and five-year OS (r = 0.91; p < 0.001, and r = 0.85; p < 0.001, respectively). The optimal cut-off value of chemotherapy-induced necrosis for five-year EFS and five-year OS was 85% and 72%, respectively. Conclusion. Chemotherapy-induced necrosis in the resected specimen showed positive correlation with EFS and OS in patients with high-grade localized osteosarcoma after MAP chemotherapy. In our analysis, optimal cut-off values of MAP chemotherapy-induced necrosis in EFS and OS were lower than the commonly used 90%, suggesting the need for re-evaluation of the optimal cut-off value through larger, international collaborative research. Cite this article: Bone Joint J 2020;102-B(6):795–803

Introduction: Limb salvage surgery has all but replaced amputation as the treatment of choice for sarcomas of the extremities. This dramatic change came about as the result of two important developments: effective chemotherapy and precision imaging techniques.In high-grade sarcomas the most significant predictors of survival are the location of the primary lesion, local control of the tumor, and the degree of necrosis in the primary tumor after intravenous neoadjuvant chemotherapy (histologic response). Aim : To detect the response to preoperative chemotherapy and correlate with the biological characteristic of osteosarcoma. Materials and method:19 Patients wih primary osteo-sarcoma were studied (follow up 9 months to 7 years). Response to preoperative chemotherapy is made histologically according to the HUVOS staging system..Combination chemotherapy was used based on the Rosen T-10 protocol (high dose methotrexate) or the platine and adriamycine protocol. Conclusions :The best response to preoperative chemotherapy was found in osteoblastic osteosarcomas (12% grade IV, 33% grade III, 33% grade II and 22% grade I tumor necrosis).Chondroplastic osteosarcomas showed less sensitivity to chemotherapy (o% grade IV, 40 % grade III, 20% grade II and 40% grade I tumor necrosis) and paraosteal and periosteal osteosarcomas were resistant to preoperarive chemotherapy

The influence of advancements in imaging and chemotherapy on patient with dedifferentiated chondrosarcoma was determined. There were forty-two cases in which twenty-seven patients received adjuvant therapy. Median survival was eight months and five-year survival was 4.8%. There was no statistical difference (p=0.62) in survival between patients who did and did not receive chemotherapy, had wide versus radical resection, or had limb sparing versus sacrificing procedures. There were no statistically significant differences between patients treated prior to 1986 and those subsequently. Despite advances, dedifferentiated chondrosarcoma continues to carry a poor prognosis. The routine adjuvant chemotherapy in this population should be questioned. The long-term survival for patients that presented with dedifferentiated chondrosarcoma has historically been poor. A large clinical series has not been analyzed in the era of modern diagnostic and treatment modalities. The current study was performed to look at the influence of advancements in imaging and chemotherapy on patient outcome. A retrospective chart review of all cases of patients presenting with dedifferentiated chondrosarcoma at our institution from 1984–2000 was performed. This was done as an extension to a study published in 1986 prior to the era of modern chemotherapy. There were forty-two cases in twenty-five men and seventeen women of average age fifty-six (range twenty-four-eighty-three years). MSTS grades at presentation were IIA(5), IIB(27), and III(10). Three patients underwent biopsy only, nineteen had limb sacrificing surgery, and twenty had limb sparing procedures. Surgical margins were intralesional in three, marginal in two, wide in twenty, and radical in fourteen. Twenty-seven patients received adjuvant therapy (twenty-two chemotherapy only, two radiotherapy only, three combined therapy). Median survival was eight months and five-year survival was 4.8%. There was no statistical difference (p=0.62) in survival between patients who did and did not receive chemotherapy, had wide versus radical resection, or had limb sparing versus sacrificing procedures. There were no statistically significant differences between patients treated prior to 1986 and those subsequently. Despite advances in diagnostic modalities, surgical treatments, and adjuvant therapies, dedifferentiated chondrosarcoma continues to carry a poor prognosis. The routine use of current adjuvant chemotherapy and its inherent risks and benefits in this population should be questioned

High grade sarcoma present a systemic metastatic progression in approximaly 50% of cases. The effectiveness of palliative chemotherapy as a treatment of systemic metastases is still controversed. The main objectif of this study is to assess disease progression and survival of patients diagnosed with metastatic soft tissue sarcomas treated with palliative chemotherapy, analyse chemotherapy treatment patterns and response to different lines of treatment. Retrospective chart review of 75 patients treated with palliative chemotherapy for metastatic soft tissue sarcomas between 2003 and 2013 at Maisonneuve-Rosemont Hospital. Data for control group of 40 patients with metastatic soft tissue sarcomas not treated with chemotherapy was collected retrospectively. Collected data include demographic data, overall survival, time free survival, type of chemotherapy treatment, surgical treatment and adverse reaction to palliative chemotherapy. Overall survival was analysed with Kaplan-Meier test. Categorial variable were compared with Log-Rank test. Seventy-five patients (37% female; mean age 50.4 years) received minimally one line of chemotherapy for their metastatic sarcomas. The regimens most commonly used in first-line were doxorubicin (48%) and doxorubicin combined with ifosfamide (21.3%). Favorable response was achieved by 38.7% in first-line and 27.9% in second-line therapy. Median overall survival with chemotherapy treatments was more than two times overall survival without treatments. Median overall survival was 19 months with chemotherapy treatments and 7 months without chemotherapy (p<0.0001). There was no statistically significant difference between survivals for treated and untreated patients with chemotherapy when analysed in term of the histological subtype, age and monotherapy versus combined treatment. Event-free survival was statistically longer during the first year for the group of patients treated with combined chemotherapy (p=0.0125). Results have shown a significantly improved overall survival in all histological groups, resulting in an OS of 19 vs 7 months for the chemotherpy and non chemotherapy group respectively. Nevertheless, patients with favorable response to chemotherapy have poor outcomes. Additional treatment options are needed

Chondrosarcoma is the second most common surgically treated primary bone sarcoma. Despite a large number of scientific papers in the literature, there is still significant controversy about diagnostics, treatment of the primary tumour, subtypes, and complications. Therefore, consensus on its day-to-day treatment decisions is needed. In January 2024, the Birmingham Orthopaedic Oncology Meeting (BOOM) attempted to gain global consensus from 300 delegates from over 50 countries. The meeting focused on these critical areas and aimed to generate consensus statements based on evidence amalgamation and expert opinion from diverse geographical regions. In parallel, periprosthetic joint infection (PJI) in oncological reconstructions poses unique challenges due to factors such as adjuvant treatments, large exposures, and the complexity of surgery. The meeting debated two-stage revisions, antibiotic prophylaxis, managing acute PJI in patients undergoing chemotherapy, and defining the best strategies for wound management and allograft reconstruction. The objectives of the meeting extended beyond resolving immediate controversies. It sought to foster global collaboration among specialists attending the meeting, and to encourage future research projects to address unsolved dilemmas. By highlighting areas of disagreement and promoting collaborative research endeavours, this initiative aims to enhance treatment standards and potentially improve outcomes for patients globally. This paper sets out some of the controversies and questions that were debated in the meeting. Cite this article: Bone Joint J 2024;106-B(5):425–429

Background. The discussion over the duration, type of therapy and regimen to be used in osteoarticular tuberculosis is losing importance in all orthopaedic gathering. Still little consensus is there over the universality of a treatment regime for osteoarticular tuberculosis. Material and Method. 340 new cases of osteoarticular tuberculosis were included in the study that were medically treated in the department of orthopaedics in a tertiary care center between 2001 and 2011. Out of which 202 cases were of spinal tuberculosis and 138 cases of extraspinal tuberculosis. 88 cases of spinal tuberculosis were treated by conventional method and 114 cases by short course chemotherapy. 60 cases of extraarticular tuberculosis were treated by conventional chemotherapy and 78 cases by short course and intermittent therapy. Results. All cases were evaluated on clinical, radiological and haematological basis. Cases who received conventional therapy received 18–24 months of treatment irrespective to the clinical, radiological and haematological parameters. Whereas those who received short course (2HRZE+4 HR) and intermittent therapy (DOTS) were evaluated for clinical improvement. Maximum follow up was of 12.8 years (conventional) minimum follow of 8 years (intermittent). The trend of fall in ESR, clinical and radiological parameters showed improvement beyond 2 years of initiation of treatment in cases that had stopped treatment at 6 months. But the improvement was slow after six months even in cases who received 24 months of chemotherapy. There were no relapses in all the three groups. Conclusion. This study reinforces that chemotherapy tailored to the response of treatment (6-9months) is the rational therapy. This study gives an insight over the evolution of different regimes as well as gives an understanding of the clinical treatment. Level of Evidence. Level 1. No relevant financial disclosures or conflicts of interest from any of the authors

Aims. Clear cell sarcoma (CCS) of soft-tissue is a rare melanocytic subtype of mesenchymal malignancy. The aim of this study was to investigate the clinical and therapeutic factors associated with increased survival, stratified by clinical stage, in order to determine the optimal treatment. Methods. The study was a retrospective analysis involving 117 patients with histologically confirmed CCS, between July 2016 and November 2017, who were enrolled in the Bone and Soft Tissue Tumour Registry in Japan. Results. The five- and ten-year survival rates were 41% (95% confidence interval (CI) 29 to 52) and 37% (95% CI 25 to 49), respectively. On multivariable analysis, the size of the tumour of > 10 cm (p = 0.006), lymph node metastasis at the time of diagnosis (p < 0.001), distant metastases at the time of diagnosis (p < 0.001), and no surgery for the primary tumour (p = 0.019) were independently associated with a poor survival. For N0M0 CCS (n = 68), the development of distant metastases was an independent prognostic factor for survival (early (< 12 months), hazard ratio (HR) 116.78 (95% CI 11.69 to 1,166.50); p < 0.001; late (> 12 months), HR 14.79 (95% CI 1.66 to 131.63); p = 0.016); neoadjuvant/adjuvant chemotherapy (p = 0.895) and/or radiotherapy (p = 0.216) were not significantly associated with survival. The five-year cumulative incidence of local recurrence was 19% (95% CI 8 to 35) and the size of the tumour was significantly associated with an increased rate of local recurrence (p = 0.012). For N1M0 CCS (n = 18), the risk of mortality was significantly lower in patients who underwent surgery for both the primary tumour and lymph node metastases (HR 0.03 (95% CI 0.00 to 0.56); p = 0.020). For M1 CCS (n = 31), excision of the primary tumour was independently associated with better survival (HR 0.26 (95% CI 0.09 to 0.76); p = 0.013). There was no significant difference in survival between the different types of systemic treatment (p = 0.523). Conclusion. Complete excision of the primary tumour and lymph nodes is associated with a better survival in patients with CCS. Systemic treatment appears to provide limited benefits, demonstrating a pressing need for novel systemic agents. Cite this article: Bone Joint J 2023;105-B(11):1216–1225

We performed a randomised, controlled clinical trial to compare ambulant short-course chemotherapy with anterior spinal fusion plus short-course chemotherapy for spinal tuberculosis without paraplegia. Patients with active disease of vertebral bodies were randomly allocated to one of three regimens: a) radical anterior resection with bone grafting plus six months of daily isoniazid plus rifampicin (Rad6); b) ambulant chemotherapy for six months with daily isoniazid plus rifampicin (Amb6); or c) similar to b) but with chemotherapy for nine months (Amb9). Ten years from the onset of treatment, 90% of 78 Rad6, 94% of 78 Amb6 and 99% of 79 Amb9 patients had a favourable status. Ambulant chemotherapy for a period of six months with daily isoniazid plus rifampicin (Amb6) was an effective treatment for spinal tuberculosis except in patients aged less than 15 years with an initial angle of kyphosis of more than 30° whose kyphosis increased substantially

Aims. The aim of this study was to identify factors that determine outcomes of treatment for patients with chondroblastic osteosarcomas (COS) of the limbs and pelvis. Patients and Methods. The authors carried out a retrospective review of prospectively collected data from 256 patients diagnosed between 1979 and 2015. Of the 256 patients diagnosed with COS of the pelvis and the limbs, 147 patients (57%) were male and 109 patients (43%) were female. The mean age at presentation was 20 years (0 to 90). Results. In all, 82% of the patients had a poor response to chemotherapy, which was associated with the presence of a predominantly chondroblastic component (more than 50% of tumour volume). The incidence of local recurrence was 15%. Synchronous or metachronous metastasis was diagnosed in 60% of patients. Overall survival was 51% and 42% after five and ten years, respectively. Limb localization and wide surgical margins were associated with a lower risk of local recurrence after multivariable analysis, while the response to chemotherapy was not. Local recurrence, advanced patient age, pelvic tumours, and large volume negatively influenced survival. Resection of pulmonary metastases was associated with a survival benefit in the limited number of patients in whom this was undertaken. Conclusion. COS demonstrates a poor response to chemotherapy and a high incidence of metastases. Wide resection is associated with improved local control and overall survival, while excision of pulmonary metastases is associated with improved survival in selected patients. Cite this article: Bone Joint J 2019;101-B:739–744

Objective: The aim of our study was to evaluate results of chemotherapy regimens and analyse prognostics factors in children with relapse of osteosarcoma. Patients and methods: From 2000–2007, we treated 57 patients with non metastatic osteosarcoma, median age 15,5 years (range 3–18). 29 pts relapsed. 26 pts with osteosarcoma relapse were treated, and 3 pts with OS relapse refused the treatment. In 24 pts pulmonary metastases were detected (7 solitary), while 2 pts had local relapse of disease. Disease free interval (DFI) was more than 1 year in 12 patients. Surgery was performed in 20 pts (17 thoracotomy, 3 amputation). Chemotherapy regimens administered were: HD IFO-VP16 (11 pts), HDMth/IFO-VP16 (6 pts), HDMth/Carbo-VP16 (9 pts). Results : During 8–116 months follow up period (Me=32 mts), disease free suvival rate was 33.12%. There was no significant difference in survival in relation to the type of chemotherapy regimen applied.Prognostic factors that influenced survival were: presence of a solitary metastasis (p= 0.026), local relapse of disease (p= 0.002), completeness of resection (p=0.043) and DFIlonger than 1 year (p= 0.039). Conclusion: The use of aggressive multimodal therapy (surgery/chemotherapy) and evaluation of prognostic factors are necessary for successful treatment in patients with osteosarcoma relapse. Chemotherapy regimen HD IFO-VP16 had better initial tumore response, but in longer follow up the survival rate was similar to other chemotherapy groups

Ewing sarcoma (ES) and Osteosarcoma (OS) are the 2 most common malignant primary bone tumors. A patient's response to neoadjuvant chemotherapy has important implications in subsequent patient management and prognosis, as a favourable response to chemotherapy allows orthopedic oncologists to be more aggressive in pursuing limb-sparing surgery. An accurate and non-invasive pre-operative marker of response would be ideal for planning surgical margins and as a prognostic tool. ES and OS have differing biological characterisitcs and respond differently to chemotherapy. We reviewed 18F-FDG PET imaging characteristics of ES and OS patients at baseline and following treatment to determine whether this biological variation is reflected in their imaging phenotype. A retrospective review of ES and OS patients treated with neoadjuvant chemotherapy and surgery was done, correlating PET results with histologic response to chemotherapy. Change in the maximum standardized Uptake Value (SUVmax) between baseline and post-treatment scanning was not significantly associated with histologic response for either ES or OS. Metabolic tumor volume (MTV) and the percentage of injected 18F-FDG dose (%ID) in the primary tumor were found to be different for ES and OS response subgroups. A 50% reduction in MTV (MTV2:1 < 0.5) was found to be significantly associated with histologic response in OS. Using the same criteria for ES incorrectly predicted good responders. Increasing the cut-offs for ES to a 90% reduction in MTV (MTV 2:1 < 0.1) resulted in association with histologic response. Response to neoadjuvant chemotherapy as reflected by changes in PET characteristics should be interpreted differently for ES and OS

The results are presented of thirty-seven patients with Ewing's sarcoma; ten were treated by a combination of operation, radiotherapy and cyclic chemotherapy, the remainder by radiotherapy and chemotherapy but without operation. The drugs, vincristine, cyclophosphamide and adriamycin were used in combination and were continued for two years. The follow-up ranged from twelve to sixty-two months. The mortality rate and the incidence of metastases were both markedly lower than in a comparable previous series treated by radiotherapy alone, or by operation plus radiotherapy, but all without chemotherapy. The percentage of local recurrences and of metastases was much higher in the twenty-seven patients who had radiotherapy and adjuvant chemotherapy, than in the ten in whom operation was also performed. It is suggested that on the basis of these results (and on theoretical grounds) treatment should consist of radiotherapy combined with chemotherapy plus, whenever feasible, operative excision of the primary tumour

Fifty-five cases of osteosarcoma of the extremities were treated between 1972 and 1976 by combined surgery and chemotherapy (vincristine, adriamycin and methotrexate in medium doses) for 18 months. The follow-up ranges from 30 to 80 months (mean = 48 months). Twenty-six patients remained free from any evidence of disease, two had local recurrences but no metastases and 27 had metastases (four of these also had local recurrences). In 12 patients, the metastases appeared after the end of chemotherapy. Both metastases and local recurrences were more frequent in patients who had segmental bone resection (7/8) than in those treated by more radical surgery (22/47). Comparison with an "historical" group (94 osteosarcoma patients treated by operation alone in our Institute between 1960 and 1971) showed that the percentage of patients free from evidence of disease was higher in the group who receiving chemotherapy. In addition, the appearance of metastases in this group was delayed (mean = 16 months) as compared with the historical controls (mean = 8 months). On the other hand, after the same kind of operative treatment, the rate of local recurrences and the time of their appearance was almost identical in both groups

We investigated the effect of adjuvant and neoadjuvant chemotherapy regimens on the tibial regenerate after removal of the external fixator in a rabbit model of distraction osteogenesis using New Zealand white rabbits. Forty rabbits were randomly distributed into two groups. In the neoadjuvant group, half of the rabbits received 1mg/kg cisplatinum & 2mg/kg adriamycin at eight weeks of age followed by 1mg/kg cisplatinum & 4mg/kg adriamycin at ten weeks of age. The remaining ten received an identical volume of normal saline using the same regimen. The adjuvant group differed only in the timing of the chemotherapy infusion. Half received the initial infusion ten days prior to the osteotomy, with the second infusion four days following the osteotomy. Again, the remaining ten rabbits received an identical volume of normal saline using the same regimen. This produced an identical interval between infusions and identical age at osteotomy in both groups. All rabbits underwent a tibial osteotomy at 12 weeks of age. Distraction started 24hours after osteotomy at a rate of 0.75mm a day for 10 days, followed by 18 days without correction to allow for consolidation of the regenerate. At week 16 there was no difference in Bone Mineral Density (BMD), Bone Mineral Content (BMC) or volumetric Bone Mineral Density (vBMD) in the adjuvant group. Neoadjuvant chemotherapy appears to have a significant detrimental effect on BMD, vBMD and BMC. Despite this there were no significant alterations in the mechanical properties of the regenerate. Histologically there was a trend for increased cortical thickness in the control groups compared to intervention however this did not prove statistically significant. In conclusion, adjuvant chemotherapy may be more beneficial for cases where distraction osteogenesis is being considered to replace segmental bone loss after tumour excision

We studied the CT and MR scans, and the histology of 50 patients with primary Ewing’s sarcoma of bone to determine the association between the change in tumour volume and necrosis after chemotherapy, and to ascertain their influence on prognosis. The mean age of the patients was 17 years. The limbs were involved in 40 and the axial bones in ten. The volume of the tumour at diagnosis varied from 31 to 1790 ml. There was a significant relationship between necrosis and the measured change in volume of the tumour after chemotherapy. Progression of the tumour despite chemotherapy was seen only in patients with necrosis of grades 4 to 6. Necrosis significantly influenced survival (p < 0.05), but the effect of change in volume was less significant. Change in volume of the tumour is a good predictor of necrosis induced by chemotherapy. Necrosis is a strong prognostic factor in Ewing’s sarcoma

Purpose. Ewings Sarcoma (ES) and Osteosarcoma (OS) behave and respond differently to chemotherapy and any interpretation of diagnostics tests to predict a patients response to treatment must consider this. We reviewed 18F-FDG PET imaging characteristics of consecutive series of ES and OS patients to determine if any differences in PET imaging existed between them. Method. A retrospective review was performed of 31 patients with ES and OS who received all their treatment by our group and who had pre- and post-chemotherapy 18F-FDG PET scans at the Peter MacCallum Cancer Centre from Jan 1, 1999 to December 1, 2009 (Table 1). Patients who did not have both their pre- and post-chemotherapy PET scans done at Peter MacCallum Cancer Centre were excluded from the study to remove bias from having different PET scanning protocols. Patients received neoadjuvant chemotherapy according to standard protocols, all starting within 2 weeks after the initial pre-chemotherapy PET scans (PET1). The PET scan taken after the last cycle of chemotherapy prior to surgery was considered as the post-chemotherapy scan (PET2). The ratio between pre and post-chemotherapy for each PET parameter was then associated with the histology response for both ES and OS, and positive (PPV) and negative predicting values (NPV) of each parameter were calculated. Results. Standardized Uptake Values (SUV) was not significantly associated with histologic response for both ES and OS. Metabolic tumor volume (MTV) and accumulation percentage of 18F-FDG (%ID) was found to be different for ES and OS. A 50% reduction in MTV (MTV2:1 < 0.5) was found to be significantly associated with histologic response in OS. Using the same criteria for ES incorrectly predicted good responders. Increasing the cut-offs for ES to a 90% reduction in MTV (MTV 2:1 < 0.1) resulted in association with histologic response. Conclusion. Response to neoadjuvant chemotherapy as reflected by changes in PET characteristics should be interpreted differently for ES and OS