Aims. Cell-free DNA (cfDNA) and circulating tumour DNA (ctDNA) are used for prognostication and monitoring in patients with carcinomas, but their utility is unclear in sarcomas. The objectives of this pilot study were to explore the prognostic significance of cfDNA and investigate whether tumour-specific alterations can be detected in the circulation of sarcoma patients. Methods. Matched tumour and blood were collected from 64 sarcoma patients (n = 70 samples) prior to resection of the primary tumour (n = 57) or disease recurrence (n = 7). DNA was isolated from plasma, quantified, and analyzed for cfDNA. A subset of cases (n = 6) underwent whole exome sequencing to identify tumour-specific alterations used to detect ctDNA using digital droplet polymerase chain reaction (ddPCR). Results. Cell-free was present in 69 of 70 samples above 0.5 ng/ml. Improved disease-free survival was found for patients with lower cfDNA levels (90% vs 48% at one-year for ≤ 6 ng/ml and > 6 ng/ml, respectively; p = 0.005). Digital droplet PCR was performed as a pilot study and mutant alleles were detectable at 0.5% to 2.5% of the wild type genome, and at a level of 0.25 ng tumour DNA. Tumour-specific alterations (ctDNA) were found in five of six cases. Conclusion. This work demonstrates the feasibility and potential utility of cfDNA and ctDNA as biomarkers for bone and soft-tissue sarcomas, despite the lack of recurrent genomic alterations. A larger study is required to validate these findings. Cite this article: Bone Joint Res 2021;10(9):602–610

Aims. Survival rates and local control after resection of a sarcoma of the pelvis compare poorly to those of the limbs and have a high incidence of complications. The outcome for patients who need a hindquarter amputation (HQA) to treat a pelvic sarcoma is poor. Our aim was to evaluate the patient, tumour, and reconstructive factors that affect the survival of the patients who undergo HQA for primary or recurrent pelvic sarcoma. Methods. We carried out a retrospective review of all sarcoma patients who had undergone a HQA in a supraregional sarcoma unit between 1996 and 2018. Outcomes included oncological, surgical, and survival characteristics. Results. A total of 136 patients, with a mean age of 51 (12 to 83) underwent HQA, 91 for a bone sarcoma and 45 for a soft tissue sarcoma. The overall survival (OS) after primary HQA for a bone sarcoma was 90.7 months (95% confidence interval (CI) 64.1 to 117.2). In patients undergoing a secondary salvage HQA it was 90.3 months (95% CI 58.1 to 122.5) (p = 0.727). For those treated for a soft tissue sarcoma (STS), the mean OS was 59.3 months (95% CI 31.1 to 88.6) for patients with a primary HQA, and 12.5 months (95% CI 9.4 to 15.5) for those undergoing a secondary salvage HQA (p = 0.038). On multivariate analysis, high histological grade (hazard ratio (HR) 2.033, 95% CI 1.127 to 3.676; p = 0.018) and a diagnosis of STS (HR 1.653, 95% CI 1.027 to 2.660; p = 0.039) were associated with a poor prognosis. The 30-day mortality for patients with curative intent was 0.8% (1/128). For those in whom surgery was carried out with palliative intent it was 33.3% (2/6) (p = 0.001). In total, 53.7% (n = 73) of patients had at least one complication with 23.5% (n = 32) requiring at least one further operation. Direct closure was inferior to flap reconstruction in terms of complete primary wound healing (60.0% (3/5) vs 82.0% (82/100); p = 0.023). Conclusion. In carefully selected patients HQA is associated with satisfactory overall survival, with a low risk of perioperative mortality, but considerable morbidity. However, caution must be exercised when considering the procedure for palliation due to the high incidence of early postoperative mortality. Cite this article: Bone Joint J 2020;102-B(6):788–794

Aims. Iliosacral sarcoma resections have been shown to have high rates of local recurrence (LR) and poor overall survival. There is also no universal classification for the resection of pelvic sarcomas invading the sacrum. This study proposes a novel classification system and analyzes the survival and risk of recurrence, when using this system. Methods. This is a retrospective analysis of 151 patients (with median follow-up in survivors of 44 months (interquartile range 12 to 77)) who underwent hemipelvectomy with iliosacral resection at a single centre between 2007 and 2019. The proposed classification differentiates the extent of iliosacral resection and defines types S1 to S6 (S1 resection medial and parallel to the sacroiliac joint, S2 resection through the ipsilateral sacral lateral mass to the neuroforamina, S3 resection through the ipsilateral neuroforamina, S4 resection through ipsilateral the spinal canal, and S5 and S6 contralateral sacral resections). Descriptive statistics and the chi-squared test were used for categorical variables, and the Kaplan-Meier survival analysis were performed. Results. Resections were S1 in 25/151 patients (17%), S2 in 70/151 (46%), S3 in 33/151 (22%), S4 in 77/151 (11%), S5 in 4/151 (3%), and S6 in 2/151 (1%). An internal hemipelvectomy was performed in 113/151 patients (75%), and 38/151 patients (25%) had an external hemipelvectomy. The predominant types of sarcoma were high-grade osteosarcoma in 48/151 patients (32%), chondrosarcoma in 41/151 (27%), Ewing sarcoma in 33/151 (22%), pleomorphic sarcoma in 17/151 (11%), and others in 2/151 (8%). LR was found in 24/151 patients (15%) with S3, S5, with S6 resections showing the highest rate of LR (p = 0.038). Overall, 19/151 patients (16%) had evidence of metastastic disease at the time of surgery and these patients showed poorer survival when compared to patients with no metastasis. Conclusion. The proposed classification can help to report and compare different surgical and reconstructive approaches in these difficult cases who are still have a considerable risk of LR. Cite this article: Bone Joint J 2022;104-B(2):290–296

Aims. The aim of this study was to evaluate the surgical management and outcome of patients with an acral soft-tissue sarcoma of the hand or foot. Patients and Methods. We identified 63 patients with an acral soft-tissue sarcoma who presented to our tertiary referral sarcoma service between 2000 and 2016. There were 35 men and 28 women with a mean age of 49 years (. sd. 21). Of the 63 sarcomas, 27 were in the hands and 36 in the feet. The commonest subtypes were epithelioid sarcoma in the hand (n = 8) and synovial sarcoma in the foot (n = 11). Results. In 41 patients (65%), the tumour measured less than 5 cm in its largest dimension (median size 3 cm (٢ to ٦)); 27 patients (43%) were diagnosed after inadvertent excision prior to their referral to the specialist sarcoma unit. After biopsy and staging, primary surgical intervention at the sarcoma unit was excision and limb salvage in 43 (68%), partial (digit or ray) amputation in 14 (22%), and more proximal amputation in six (10%). At final follow up, local recurrence had been treated by one partial amputation and six amputations, resulting in a partial amputation rate of 24% and a proximal amputation rate of 19%. The five-year survival rate was 82%. Patients who underwent inadvertent excision showed no statistically significant difference in survival or local recurrence, but were more likely to undergo amputation (p = 0.008). Large tumour size (> 5 cm) was associated with lower survival (p = 0.04) and a higher risk of local recurrence (p = ٠.٠٠٩). Conclusion. Most acral soft-tissue sarcomas measure less than 5 cm at presentation, indicating that while size can be a useful prognostic factor, it should not be used as a diagnostic threshold for referral. Increased tumour size is associated with a higher rate of local recurrence and reduced survival. Sarcoma excision with limb preservation does not result in an increased risk of local recurrence. Cite this article: Bone Joint J 2018;100-B:1518–23

Aims. The aims of the study were to analyze differences in surgical and oncological outcomes, as well as quality of life (QoL) and function in patients with ankle sarcomas undergoing three forms of surgical treatment, minor or major limb salvage surgery (LSS), or amputation. Methods. A total of 69 patients with ankle sarcomas, treated between 1981 and 2017 at two tumour centres, were retrospectively reviewed (mean age at surgery: 46.3 years (SD 22.0); 31 females (45%)). Among these 69 patients 25 were analyzed prospectively (mean age at latest follow-up: 61.2 years (SD 20.7); 11 females (44%)), and assessed for mobility using the Prosthetic Limb Users Survey of Mobility (PLUS-M; for amputees only), the Toronto Extremity Salvage Score (TESS), and the University of California, Los Angeles (UCLA) Activity Score. Individual QoL was evaluated in these 25 patients using the five-level EuroQol five-dimension (EQ-5D-5L) and Fragebogen zur Lebenszufriedenheit/Questions on Life Satisfaction (FLZ). Results. Of the total number of patients in the study, 22 (32%) underwent minor LSS and 22 (32%) underwent major LSS; 25 underwent primary amputation (36%). Complications developed in 26 (38%) patients, and were more common in those with major or minor LSS in comparison to amputation (59% vs 36% vs 20%; p = 0.022). A time-dependent trend towards higher complication risk following any LSS was present (relative risk: 0.204; 95% confidence interval (CI) 0.026 to 1.614; p = 0.095). In the prospective cohort, mean TESS was higher following minor LSS in comparison to amputation (91.0 vs 67.3; p = 0.006), while there was no statistically significant difference between major LSS and amputation (81.6 vs 67.3; p = 0.099). There was no difference in mean UCLA (p = 0.334) between the three groups (p = 0.334). None of the items in FLZ or EQ-5D-5L were different between the three groups (all p > 0.05), except for FLZ item “self-relation”, being lower in amputees. Conclusion. Complications are common following LSS for ankle sarcomas. QoL is comparable between patients with LSS or amputation, despite better mobility scores for patients following minor LSS. We conclude that these results allow a decision for amputation to be made more easily in patients particularly where the principles of oncological surgery would otherwise be at risk. Cite this article: Bone Joint J 2021;103-B(3):553–561

Aims. Current literature suggests that survival outcomes and local recurrence rates of primary soft-tissue sarcoma diagnosed in the very elderly age range, (over 90 years), are comparable with those in patients diagnosed under the age of 75 years. Our aim is to quantify these outcomes with a view to rationalizing management and follow-up for very elderly patients. Methods. Retrospective access to our prospectively maintained oncology database yielded a cohort of 48 patients across 23 years with a median follow-up of 12 months (0 to 78) and mean age at diagnosis of 92 years (90 to 99). Overall, 42 of 48 of 48 patients (87.5%) were managed surgically with either limb salvage or amputation. Results. A lower overall local recurrence rate (LRR) was seen with primary amputations compared with limb salvage (p > 0.050). The LRR was comparable between free (R0), microscopically (R1), and macroscopically positive (R2) resection margins in the limb salvage group. Amputation was also associated with longer survival times (p < 0.050). Overall median survival time was limited to 20 months (0 to 80). Conclusion. Early and aggressive treatment with appropriate oncological surgery confers the lowest LRR and a survival advantage versus conservative treatment in this cohort of patients. With limited survival, follow-up can be rationalized on a patient-by-patient basis using alternative means, such as GP, local oncology, and/or patient-led follow-up. Cite this article: Bone Joint J 2022;104-B(1):177–182

Objectives. In this cross sectional study, the impact and the efficacy of a surveillance programme for sarcomas of the extremities was analysed. Methods. All patients who had treatment with curative intent for a high-grade sarcoma and were diagnosed before 2014 were included and followed for a minimum of two years. Results. Of the 909 patients who had a review appointment in 2014, 131 were under review for a high-grade sarcoma of the extremities following treatment with curative intent. Of these patients, three patients died of disease, two patients died of other causes, 12 are alive, with disease, and 114 have no evidence of disease. The surveillance programme accounts for 14% of all review appointments. Four of five patients (80%) who developed local recurrence identified the recurrence themselves. Chest radiographs are adequate in identifying metastatic disease and 11 (73%) of metastases were diagnosed during a routine follow up visit. However, the chance of cure is small and only two patients were referred for a metastatectomy. Of these only one survived for more than two years. The mean time for developing metastatic disease and local recurrence was 2.0 and 3.9 years respectively. Once identified, the mean time to death was 2.1 years for patients with metastatic disease. Conclusions. Surveillance of sarcoma patients makes up a substantial amount of the workload of a sarcoma unit. The chance of cure following identification of local recurrence or metastatic disease, however, is small. Alternative methods of surveillance that allow better evaluation of the patient’s needs are recommended. Cite this article: P. Cool, G. Cribb. The impact and efficacy of surveillance in patients with sarcoma of the extremities. Bone Joint Res 2017;6:224–230. DOI: 10.1302/2046-3758.64.BJR-2016-0253.R1

Aims. The modified Glasgow Prognostic Score (mGPS) uses preoperative CRP and albumin to calculate a score from 0 to 2 (2 being associated with poor outcomes). mGPS is validated in multiple carcinomas. To date, its use in soft-tissue sarcoma (STS) is limited, with only small cohorts reporting that increased mGPS scores correlates with decreased survival in STS patients. Methods. This retrospective multicentre cohort study identified 493 STS patients using clinical databases from six collaborating hospitals in three countries. Centres performed a retrospective data collection for patient demographics, preoperative blood results (CRP and albumin levels and neutrophil, leucocyte, and platelets counts), and oncological outcomes (disease-free survival, local, or metastatic recurrence) with a minimum of two years' follow-up. Results. We found that increased mGPS, tumour size, grade, neutrophil/lymphocyte ratio, and disease recurrence were associated with reduced survival. Importantly, mGPS was the best at stratifying prognosis and could be used in conjunction with tumour grade to sub-stratify patient survival. Conclusion. This study demonstrated that prognosis of localized STS strongly correlates with mGPS, as an increasing score is associated with a poorer outcome. We note that 203 patients (41%) with an STS have evidence of systemic inflammation. We recommend the mGPS and other biochemical blood indicators be introduced into the routine diagnostic assessment in STS patients to stratify patient prognosis. Its use will support clinical decision-making, especially when morbid treatment options such as amputation are being considered. Cite this article: Bone Joint J 2022;104-B(1):168–176

This article provides an overview of the role of genomics in sarcomas and describes how new methods of analysis and comparative screening have provided the potential to progress understanding and treatment of sarcoma. This article reviews genomic techniques, the evolution of the use of genomics in cancer, the current state of genomic analysis, and also provides an overview of the medical, social and economic implications of recent genomic advances

Aims. The purpose of this study was to report the long-term results of extendable endoprostheses of the humerus in children after the resection of a bone sarcoma. Methods. A total of 35 consecutive patients treated with extendable endoprosthetic replacement of the humerus in children were included. There were 17 boys and 18 girls in the series with a median age at the time of initial surgery of nine years (interquartile range (IQR) 7 to 11). Results. The median follow-up time was 10.6 years (IQR 3.9 to 20.4). The overall implant survival at ten years was 75%. Complications occurred in 13 patients (37%). Subluxation at the proximal humerus occurred in 19 patients (54%) but only six (17%) were symptomatic. Subluxation was seen more commonly in children under the age of nine years (86%) than in those aged nine years or more (33%) (p = 0.002). Implant failure occurred in nine patients (26%): the most common cause was aseptic loosening (four patients, 11%). Lengthening of the implant was carried out in 23 patients (66%). At final follow up, three patients had a limb that was shortened by 5 cm or more. The mean Musculoskeletal Tumor Society (MSTS) functional score was 79% (73% to 90%). Conclusion. Extendable endoprosthetic replacement is a reliable method of reconstructing humerus after excision of a bone sarcoma. Children who are less than nine years old have a high risk of subluxation. Cite this article: Bone Joint J 2020;102-B(1):64–71

Aims. Preserving growth following limb-salvage surgery of the upper limb in children remains a challenge. Vascularized autografts may provide rapid biological incorporation with the potential for growth and longevity. In this study, we aimed to describe the outcomes following proximal humeral reconstruction with a vascularized fibular epiphyseal transfer in children with a primary sarcoma of bone. We also aimed to quantify the hypertrophy of the graft and the annual growth, and to determine the functional outcomes of the neoglenofibular joint. Patients and Methods. We retrospectively analyzed 11 patients who underwent this procedure for a primary bone tumour of the proximal humerus between 2004 and 2015. Six had Ewing’s sarcoma and five had osteosarcoma. Their mean age at the time of surgery was five years (two to eight). The mean follow-up was 5.2 years (1 to 12.2). Results. The overall survival at five and ten years was 91% (confidence interval (CI) 95% 75% to 100%). At the time of the final review, ten patients were alive. One with local recurrence and metastasis died one-year post-operatively. Complications included seven fractures, four transient nerve palsies, and two patients developed avascular necrosis of the graft. All the fractures presented within the first postoperative year and united with conservative management. One patient had two further operations for a slipped fibular epiphysis of the autograft, and a hemi-epiphysiodesis for lateral tibial physeal arrest. Hypertrophy and axial growth were evident in nine patients who did not have avascular necrosis of the graft. The mean hypertrophy index was 65% (55% to 82%), and the mean growth was 4.6 mm per annum (2.4 to 7.6) in these nine grafts. At final follow-up, the mean modified functional Musculoskeletal Tumour Society score was 77% (63% to 83%) and the mean Toronto Extremity Salvage Score (TESS) was 84% (65% to 94%). Conclusion. Vascularized fibular epiphyseal transfer preserves function and growth in young children following excision of the proximal humerus for a malignant bone tumour. Function compares favourably to other limb-salvage procedures in children. Longer term analysis is required to determine if this technique proves to be durable into adulthood. Cite this article: Bone Joint J 2018;100-B:535–41

Aims. The aim of the study was to investigate the controversial issue of whether the pelvic ring should be reconstructed following resection of the sarcomas of the ilium. Patients and Methods. From our database, we identified 64 patients who underwent excision of a tumour involving the ilium between 1976 and 2015. A total of 35 underwent complete resection, of whom 24 were reconstructed with a non-vascularised fibula graft, and four with extracorporeal irradiation and reimplantation. A total of 29 patients had a partial resection. The mean follow-up was 9.2 years (1.1 to 25.6). Functional outcomes were assessed using the Toronto Extremity Salvation Score (TESS) at final follow-up. In all, 32 patients (50%) had a chondrosarcoma. Results. The mean TESS for all patients was 71.6% (17% to 100%). The mean TESS for those who underwent total resection with reconstruction was 72.0% (17% to 100%) and without reconstruction it was 53.3% (20% to 90%) and for those who underwent partial resection it was 76.3% (31.3% to 100%). The rate of local recurrence was 42.2% and this was more common in those treated by partial resection (p = 0.048). The risk of local recurrence was related to the margin achieved at resection. Conclusions. Given the high rate of local recurrence following excision of a tumour from the ilium, obtaining wide surgical margins should be a priority even if this requires more aggressive surgery. In young patients, where late recurrence may occur, more radical complete resection should be considered. When total resection of the ilium is considered, reconstruction should also be considered as it confers a higher functional outcome than total resection without reconstruction. Cite this article: Bone Joint J 2017;99-B:538–43

Bone sarcomas are rare cancers and orthopaedic surgeons come across them infrequently, sometimes unexpectedly during surgical procedures. We investigated the outcomes of patients who underwent a surgical procedure where sarcomas were found unexpectedly and were subsequently referred to our unit for treatment. We identified 95 patients (44 intra-lesional excisions, 35 fracture fixations, 16 joint replacements) with mean age of 48 years (11 to 83); 60% were males (n = 57). Local recurrence arose in 40% who underwent limb salvage surgery versus 12% who had an amputation. Despite achieving local control, overall survival was worse for patients treated with amputation rather than limb salvage (54% vs 75% five-year survival). Factors that negatively influenced survival were invasive primary surgery (fracture fixation, joint replacement), a delay of greater than two months until referral to our oncology service, and high-grade tumours. Survival in these circumstances depends mostly on factors that are determined prior to definitive treatment by a tertiary orthopaedic oncology unit. Limb salvage in this group of patients is associated with a higher rate of inadequate marginal surgery and, consequently, higher local recurrence rates than amputation, but should still be attempted whenever possible, as local control is not the primary determinant of survival. . Cite this article: Bone Joint J 2014;96-B:665–72

We analysed the outcome of patients with primary non-metastatic diaphyseal sarcomas who had en bloc resection with preservation of the adjoining joints and reconstruction with re-implantation of sterilised tumour bone after extracorporeal radiation (50 Gy). Between March 2005 and September 2009, 32 patients (16 Ewing’s sarcoma and 16 osteogenic sarcoma) with a mean age of 15 years (2 to 35) underwent this procedure. The femur was the most common site in 17 patients, followed by the tibia in 11, humerus in three and ulna in one. The mean resected length of bone was 19 cm (10 to 26). A total of 31 patients were available at a mean follow-up of 34 months (12 to 74). The mean time to union for all osteotomy sites was 7.3 months (3 to 28): metaphyseal osteotomy sites united quicker than diaphyseal osteotomy sites (5.8 months (3 to 10) versus 9.5 months (4 to 28)). There were three local recurrences, all in soft-tissue away from irradiated graft. At the time of final follow-up, 19 patients were free of disease, one was alive with disease and 11 had died of disease. The mean Musculoskeletal Tumor Society Score for 29 patients evaluated at the last follow-up was 26 (9 to 30). Extracorporeal irradiation is an oncologically safe and inexpensive technique for limb salvage in diaphyseal sarcomas and has good functional results

Paediatric bone sarcomas are a dual challenge for orthopaedic surgeons in terms of tumour resection and reconstruction, as it is important to minimize functional and growth problems without compromising survival rates. Cañadell’s technique consists of a Type I epiphysiolysis performed using continuous distraction by an external fixator prior to resection. It was designed to achieve a safe margin due to the ability of the physeal cartilage to be a barrier to tumour spread in some situations, avoiding the need for articular reconstruction, and preserving the growth capacity most of the times. Despite initial doubts raised in the scientific community, this technique is now widely used in many countries for the treatment of metaphyseal paediatric bone sarcomas. This annotation highlights the importance of Cañadell’s work and reviews the experience of applying it to bone sarcoma patients over the last 40 years. Cite this article: Bone Joint J 2023;105-B(1):11–16

Aims. Socioeconomic and racial disparities have been recognized as impacting the care of patients with cancer, however there are a lack of data examining the impact of these disparities on patients with bone sarcoma. The purpose of this study was to examine socioeconomic and racial disparities that impact the oncological outcomes of patients with bone sarcoma. Methods. We reviewed 4,739 patients diagnosed with primary bone sarcomas from the Surveillance, Epidemiology and End Results (SEER) registry between 2007 and 2015. We examined the impact of race and insurance status associated with the presence of metastatic disease at diagnosis, treatment outcome, and overall survival (OS). Results. Patients with Medicaid (odds ratio (OR) 1.41; 95% confidence interval (CI) 1.15 to 1.72) and uninsured patients (OR 1.90; 95% CI 1.26 to 2.86) had higher risks of metastatic disease at diagnosis compared to patients with health insurance. Compared to White patients, Black (OR 0.63, 95% CI 0.47 to 0.85) and Asian/Pacific Islander (OR 0.65, 95% CI 0.46 to 0.91) were less likely to undergo surgery. In addition, Black patients were less likely to receive chemotherapy (OR 0.67, 95% CI 0.49 to 0.91) compared to White patients. In patients with chondrosarcoma, those with Medicaid had worse OS compared to patients with insurance (hazard ratio (HR) 1.65, 95% CI 1.06 to 2.56). Conclusion. In patients with a bone sarcoma, the cancer stage at diagnosis varied based on insurance status, and racial disparities were identified in treatment. Further studies are needed to identify modifiable factors which can mitigate socioeconomic and racial disparities found in patients with bone sarcomas. Cite this article: Bone Joint Res 2022;11(5):278–291

Aims. The risk of postoperative complications after resection of soft-tissue sarcoma in the medial thigh is higher than in other locations. This study investigated whether a vessel sealing system (VSS) could help reduce the risk of postoperative complications after wide resection of soft-tissue sarcoma in the medial thigh. Methods. Of 285 patients who underwent wide resection for soft-tissue sarcoma between 2014 and 2021 at our institution, 78 patients with tumours in the medial thigh were extracted from our database. Information on clinicopathological characteristics, preoperative treatment, surgical treatment (use of VSS, blood loss volume, operating time), and postoperative course (complications, postoperative haemoglobin changes, total drainage volume, and drainage and hospitalization durations) were obtained from medical records. We statistically compared clinical outcomes between patients whose surgery did or did not use VSS (VSS and non-VSS groups, respectively). Results. There were 24 patients in the VSS group and 54 in the non-VSS group. There were no significant differences between the two groups in terms of clinicopathological background. The total drainage volume in the VSS group was significantly less than that in the non-VSS group (1,176 ml vs 3,114 ml; p = 0.018). Moreover, the drainage and hospitalization durations were significantly shorter in the VSS group compared to the non-VSS group (p = 0.017 and p = 0.024, respectively). Conclusion. Our results suggest that use of VSS can help reduce the risk of postoperative complications after wide resection of soft-tissue sarcoma in the medial thigh. Cite this article: Bone Jt Open 2023;4(6):442–446

Aims. The aim of this study was to identify factors associated with five-year cancer-related mortality in patients with limb and trunk soft-tissue sarcoma (STS) and develop and validate machine learning algorithms in order to predict five-year cancer-related mortality in these patients. Methods. Demographic, clinicopathological, and treatment variables of limb and trunk STS patients in the Surveillance, Epidemiology, and End Results Program (SEER) database from 2004 to 2017 were analyzed. Multivariable logistic regression was used to determine factors significantly associated with five-year cancer-related mortality. Various machine learning models were developed and compared using area under the curve (AUC), calibration, and decision curve analysis. The model that performed best on the SEER testing data was further assessed to determine the variables most important in its predictive capacity. This model was externally validated using our institutional dataset. Results. A total of 13,646 patients with STS from the SEER database were included, of whom 35.9% experienced five-year cancer-related mortality. The random forest model performed the best overall and identified tumour size as the most important variable when predicting mortality in patients with STS, followed by M stage, histological subtype, age, and surgical excision. Each variable was significant in logistic regression. External validation yielded an AUC of 0.752. Conclusion. This study identified clinically important variables associated with five-year cancer-related mortality in patients with limb and trunk STS, and developed a predictive model that demonstrated good accuracy and predictability. Orthopaedic oncologists may use these findings to further risk-stratify their patients and recommend an optimal course of treatment. Cite this article: Bone Joint J 2023;105-B(6):702–710

Prediction tools are instruments which are commonly used to estimate the prognosis in oncology and facilitate clinical decision-making in a more personalized manner. Their popularity is shown by the increasing numbers of prediction tools, which have been described in the medical literature. Many of these tools have been shown to be useful in the field of soft-tissue sarcoma of the extremities (eSTS). In this annotation, we aim to provide an overview of the available prediction tools for eSTS, provide an approach for clinicians to evaluate the performance and usefulness of the available tools for their own patients, and discuss their possible applications in the management of patients with an eSTS. Cite this article: Bone Joint J 2022;104-B(9):1011–1016

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