B cells are associated with survival and immunotherapy response in sarcoma.

Soft-tissue sarcomas represent a heterogeneous group of cancer, with more than 50 histological subtypes1,2. The clinical presentation of patients with different subtypes is often atypical, and responses to therapies such as immune checkpoint blockade vary widely3,4. To explain this clinical variability, here we study gene expression profiles in 608 tumours across subtypes of soft-tissue sarcoma. We establish an immune-based classification on the basis of the composition of the tumour microenvironment and identify five distinct phenotypes: immune-low (A and B), immune-high (D and E), and highly vascularized (C) groups. In situ analysis of an independent validation cohort shows that class E was characterized by the presence of tertiary lymphoid structures that contain T cells and follicular dendritic cells and are particularly rich in B cells. B cells are the strongest prognostic factor even in the context of high or low CD8+ T cells and cytotoxic contents. The class-E group demonstrated improved survival and a high response rate to PD1 blockade with pembrolizumab in a phase 2 clinical trial. Together, this work confirms the immune subtypes in patients with soft-tissue sarcoma, and unravels the potential of B-cell-rich tertiary lymphoid structures to guide clinical decision-making and treatments, which could have broader applications in other diseases.

Safety and efficacy of percutaneous image-guided ablation for soft tissue sarcoma metastases to the liver.

PURPOSE: To evaluate outcomes following percutaneous image-guided ablation of soft tissue sarcoma metastases to the liver. MATERIALS AND METHODS: A single-institution retrospective analysis of patients with a diagnosis of metastatic soft tissue sarcoma who underwent percutaneous image-guided ablation of hepatic metastases between January 2011 and December 2021 was performed. Patients with less than 60 days of follow-up after ablation were excluded. The primary outcome was local tumor progression-free survival (LPFS). Secondary outcomes included overall survival, liver-specific progression-free survival. and chemotherapy-free survival. RESULTS: Fifty-five patients who underwent percutaneous ablation for 84 metastatic liver lesions were included. The most common histopathological subtypes were leiomyosarcoma (23/55), followed by gastrointestinal stromal tumor (22/55). The median treated liver lesions was 2 (range, 1-8), whereas the median size of metastases were 1.8 cm (0.3-8.7 cm). Complete response at 2 months was achieved in 90.5% of the treated lesions. LPFS was 83% at 1 year and 80% at 2 years. Liver-specific progression-free survival was 66% at 1 year and 40% at 2 years. The overall survival at 1 and 2 years was 98% and 94%. The chemotherapy-free holiday from the start of ablation was 71.2% at 12 months. The complication rate was 3.6% (2/55); one of the complications was Common Terminology Criteria for Adverse Events grade 3 or higher. LPFS subgroup analysis for leiomyosarcoma versus gastrointestinal stromal tumor suggests histology-agnostic outcomes (2 years, 89% vs 82%, p = .35). CONCLUSION: Percutaneous image-guided liver ablation of soft tissue sarcoma metastases is safe and efficacious.

Moderately hypofractionated, preoperative radiotherapy in patients with soft tissue sarcomas (HYPORT-STS): Updated local control, late toxicities, and patient-reported outcomes.

BACKGROUND: Moderately hypofractionated, preoperative radiotherapy in patients with soft tissue sarcomas (HYPORT-STS; ClinicalTrials.gov identifier NCT03819985) investigated a radiobiologically equivalent, moderately hypofractionated course of preoperative radiotherapy (RT) 15 × 2.85 Gy in patients with soft tissue sarcoma (STS). Here, the authors report longer term follow-up to update local control and report late toxicities, as well as functional and patient-reported outcomes. METHODS: HYPORT-STS was a single-center, open-label, single-arm, prospective phase 2 clinical trial that enrolled 120 eligible adult patients with localized STS of the extremities or superficial trunk between 2018 and 2021. Patients received a 3-week course of preoperative RT followed by surgery 4-8 weeks later. End points and follow-up were analyzed from the date of surgery. RESULTS: The median follow-up was 43 months (interquartile range, 37-52 months), and the 4-year local recurrence-free survival rate was 93%. Overall RT-related late toxicities improved with time from local therapy (p < .001), and few patients had grade ≥2 toxicities (9%; n = 8 of 88) at 2 years. These included: 2% grade ≥2 skin toxicity, 2% fibrosis, 3% lymphedema, and 1% joint stiffness. Four patients (3%) had bone fractures. Both functional outcomes, as measured by the Musculoskeletal Tumor Society Rating Scale (p < .001), and quality of life, as measured by the Functional Assessment of Cancer Therapy-General (p < .001), improved with time from treatment, and both measures were better in follow-up at 2 years compared with baseline. CONCLUSIONS: Long-term follow up suggests that moderately hypofractionated preoperative RT for patients with STS is safe and effective. Higher grade late toxicities affect a minority of patients. Late toxicities decrease over time, whereas functional outcomes and health-related quality of life seem to improve with more time from combined modality treatment.

Clinical Variables Influencing Outcomes in Patients with Atypical Intradermal Smooth Muscle Neoplasms (Formerly Cutaneous Leiomyosarcomas): Single-Institution Study of 95 Surgical Patients.

BACKGROUND: Atypical intradermal smooth muscle neoplasm, also commonly termed cutaneous leiomyosarcoma, is a soft tissue tumor with a low risk of aggressive behavior. These lesions arise in the dermis with possible superficial subcutaneous extension, demonstrate cytologic atypia, and often show mitotic activity. METHODS: A retrospective review of patient demographics, tumor characteristics, and treatment methods was conducted in a consecutive series of patients presenting to MD Anderson Cancer Center (MDACC) from 2002 to 2021 (n = 95). All pathology was reviewed by MDACC pathologists and determined to be atypical intradermal smooth muscle neoplasm. RESULTS: Median age at diagnosis was 58 years (range 22-86), and 74% were male. Ninety-five percent (n = 90) of patients identified as White, non-Hispanic. Most tumors were slow-growing, solitary, and painless nodules. Tumors were in the lower extremities (44.2%), followed by the upper extremity (28.4%), trunk (22.1%), and head and neck (5.2%). All patients (n = 44, 46.3%) who had a punch/incisional biopsy for diagnostic purposes had a subsequent tumor excision. Unplanned excision or excisional biopsy was performed on the remaining 46 (48%) patients. Of this subset, 41 of the 46 aforementioned patients (89%) had positive margins and underwent re-excision. Final pathology in 25/38 (66%) re-excision specimens was negative for residual tumor despite an initial positive margin. Two patients in the cohort had local recurrence 2 and 3 years after initial surgery. Both patients had positive margins, underwent excision of the recurrent tumor, and remain free of disease. After median follow-up of 6.9 years (range 1 day-18 years), 5-year recurrence-free survival was 96% and overall survival (OS) of the entire cohort was 78%. CONCLUSION: In this study of consecutive patients presenting with atypical intradermal smooth muscle neoplasm, we found good OS and local control after definitive surgical excision with negative margins, including excisional biopsy with close margins. Atypical intradermal smooth muscle neoplasm is unlikely to metastasize and has an excellent prognosis. Guidelines to determine optimal surveillance strategies for these patients should be revisited.

Sarcoma Size and Limb Dimensions Predict Complications, Recurrence, and Death in Patients with Soft Tissue Sarcoma in the Thigh: A Multidimensional Analysis.

BACKGROUND: Limb-sparing resections of thigh soft tissue sarcomas (STSs) can result in adverse outcomes. Identifying preoperative predictors for wound healing complications, tumor recurrence, and mortality is crucial for informed reconstructive decision-making. We hypothesized that preoperative measurements of thigh and tumor dimensions could serve as reliable indicators for postoperative complications, recurrence, and death. PATIENTS AND METHODS: In this retrospective cohort study conducted from March 2016 to December 2021, we analyzed patients undergoing thigh STS excisions followed by reconstruction. Preoperative magnetic resonance imaging or computed tomography scans provided necessary thigh and tumor dimensions. Univariate and multivariate regression assessed relationships between these dimensions and postoperative outcomes, including complications, recurrence, and death. RESULTS: Upon the analysis of 123 thighs, we found thigh width to be highly predictive of postoperative complications, even surpassing body mass index (BMI) and retaining significance in multivariate regression [odds ratio (OR) 1.19; 95% CI 1.03-1.39; p = 0.03]. Sarcoma-to-thigh width and thickness ratios predicted STS recurrence, with the thickness ratio retaining significance in multivariate regression (OR 1.03; 95% CI 1.001-1.05; p = 0.041). Notably, greater thigh thickness was independently protective against mortality in multivariate analysis (OR 0.80; 95% CI 0.65-0.98; p = 0.030). CONCLUSIONS: Thigh width outperformed BMI in association with postoperative complications. This may create an opportunity for intervention, where weight loss can play a role during the neoadjuvant therapy period to potentially reduce complications. Sarcoma-to-thigh width and thickness ratios, particularly the latter, hold substantial predictive value in terms of STS recurrence. Moreover, thigh thickness is an independent predictor of survival.

Patterns of Care and Outcomes of Patients with Small Gastrointestinal Stromal Tumors at a High-Volume Sarcoma Center.

BACKGROUND: The course of subclinical gastrointestinal stromal tumors (GISTs) is variable. The management of small GISTs is not well-defined. METHODS: Records of patients presenting with small GISTs with documented follow-up appointment at our institution between 2016 and 2022 were identified and reviewed. Comparative univariate analysis to compare patient and tumor characteristics and outcomes was performed. RESULTS: Eighty-six patients were followed for a median of 3.7 years (range 0.1-20 years). The median size at presentation was 1.7 (range 0.1-2.5) cm. A total of 51.2% (n = 44) underwent surgery before or immediately after initial presentation for pain (18.2%), bleeding (15.9%), or patient preference (6.8%). Another 17.4% (n = 15) had delayed surgery for tumor growth (40%), patient preference (2.7%), bleeding (6.7%), or pain (6.7%). The remaining 31.4% (n = 27) of patients never underwent surgery for reasons that included no growth/stability (44.4%), concomitant cancer diagnosis/treatment (29.6%), comorbidities (14.8%), and patient preference (3.7%). Patients who underwent surveillance without intervention compared with those who had delayed surgery were older (71.1 vs. 60.8 years, p < 0.001) with multiple comorbidities or a concurrent cancer diagnosis (70.3% vs. 20%, p = 0.005). There were no differences in survival or rate of distant metastases. Average time to surgery in the delayed group was 2 (range 0.1-10.3) years, and 86% of these patients underwent surgery by 5.5 years after diagnosis. CONCLUSIONS: In older patients with comorbidities or concurrent cancer diagnoses, opting out of surgery does not affect survival. Conversely, younger patients, free from significant comorbidities or other diagnoses, may consider surgery or active surveillance for up to 5 years, with comparable outcomes.

High Community-Level Social Vulnerability is Associated with Worse Recurrence-Free Survival (RFS) After Resection of Extremity and Truncal Soft Tissue Sarcoma.

BACKGROUND: Although social vulnerability has been associated with worse postoperative and oncologic outcomes in other cancer types, these effects have not been characterized in patients with soft tissue sarcoma. This study evaluated the association of social vulnerability and oncologic outcomes. METHODS: The authors conducted a single-institution cohort study of adult patients with primary and locally recurrent extremity or truncal soft tissue sarcoma undergoing resection between January 2016 and December 2021. The social vulnerability index (SVI) was measured on a low (SVI 1-39%, least vulnerable) to high (60-100%, most vulnerable) SVI scale. The association of SVI with overall survival (OS) and recurrence-free survival (RFS) was evaluated by Kaplan-Meier analysis and Cox proportional hazard regression. RESULTS: The study identified 577 patients. The median SVI was 44 (interquartile range [IQR], 19-67), with 195 patients categorized as high SVI and 265 patients as low SVI. The median age, tumor size, histologic subtype, grade, comorbidities, stage, follow-up time, and perioperative chemotherapy and radiation utilization were similar between the high and low SVI cohorts. The patients with high SVI had worse OS (p = 0.07) and RFS (p = 0.016) than the patients with low SVI. High SVI was independently associated with shorter RFS in the multivariate analysis (hazard ratio, 1.64; 95% confidence interval, 1.06-2.54) but not with OS (HR, 1.47; 95% CI 0.84-2.56). CONCLUSION: High community-level social vulnerability appears to be independently associated with worse RFS for patients undergoing resection of extremity and truncal soft tissue sarcoma. The effect of patient and community-level social risk factors should be considered in the treatment of patients with extremity sarcoma.

When to ditch the ladder and take the elevator: The Anderson SArcoma Risk of Complications (A-SARC) score to guide reconstructive decision-making in extremity soft tissue sarcoma patients.

BACKGROUND: The reconstructive ladder relies mostly on defect size and depth to determine reconstructive technique, however, in actuality, many more variables ultimately inform reconstructive decision making, especially regarding extremity soft tissue sarcoma (eSTS) defects. The purpose of this study was to describe eSTS patients who will most optimally benefit from an advanced method of reconstruction (defined as a pedicled regional flap or free flap) and to create a simple risk assessment scale that can be employed in clinical practice. STUDY DESIGN: A single-institution retrospective cohort study examined patients undergoing resection of soft tissue sarcoma affecting the upper or lower extremities between 2016 and 2021. We categorized patients who required a pedicled or free flap as having had advanced reconstruction, and all other techniques were considered simple reconstruction. A regression was used to create a risk scale to guide reconstructive decision-making. RESULTS: The following variables were identified as independent predictors of complications and used to create our risk scale: lower extremity tumor location, preoperative radiotherapy, tumor bed excision, male sex, hypertension, and tumor volume. Intermediate and high-risk patients reconstructed using simple techniques had significantly greater overall complication rates compared to those reconstructed with advanced techniques. Major complications were significantly greater in low-risk patients reconstructed with advanced techniques. CONCLUSIONS: To minimize postoperative wound complications, low-risk patients should receive simple methods of reconstruction, whereas high-risk patients should be reconstructed using advanced techniques.

Safety and Efficacy of Percutaneous Cryoablation for Recurrent or Metastatic Soft-Tissue Sarcoma in Adult Patients.

BACKGROUND. Treatment options are limited in patients with recurrent or metastatic disease after initial treatment of soft-tissue sarcoma (STS) by surgical resection, radiation, or systemic therapy. Percutaneous cryoablation may provide a complementary minimally invasive option in this setting. OBJECTIVE. The purpose of this article was to assess the safety and efficacy of percutaneous cryoablation performed for local control of treatment-refractory recurrent or metastatic STS. METHODS. This single-institution retrospective study included adult patients who underwent percutaneous cryoablation from January 2016 to April 2023 to achieve local control of recurrent or metastatic STS after earlier treatment (surgery, radiation, or chemotherapy). For each treated lesion, a single interventional radiologist rereviewed intraprocedural images to assess for adequate coverage by the ice ball of the entire lesion and a 5-mm or greater margin in all dimensions. Complications and outcomes were extracted from medical records. The primary end point for procedure efficacy was 1-year local progression-free survival. RESULTS. The study included 141 patients (median age, 66 years; 90 women, 51 men) who underwent 217 cryoablation procedures to treat 250 recurrent or metastatic STS lesions. The most common STS histologic types were leiomyosarcoma (56/141) and liposarcoma (39/141). Lesions had a mean long-axis diameter of 2.0 cm (range, 0.4-11.0 cm). Adequate ice-ball coverage was achieved for 82% (204/250) of lesions. The complication rate was 2% (4/217), including three major complications and one minor complication. Patients' median postablation follow-up was 25 months (range, 3-80 months). Local progression-free survival rate was 86% at 1 year and 79% at 2 years. The chemotherapy-free survival rate was 45% at 1 year and 31% at 2 years. The overall survival (OS) rate was 89% at 1 year and 80% at 2 years. In Kaplan-Meier analysis, leiomyosarcoma, in comparison with liposarcoma, had significantly higher local progression-free survival but no significant difference in OS. In multivariable analysis, factors independently associated with an increased risk for local progression included inadequate ice-ball coverage (HR = 7.34) and a lesion location of peritoneum (HR = 3.63) or retroperitoneum (HR = 3.71) relative to lung. CONCLUSION. Percutaneous cryoablation has a favorable safety and efficacy profile in patients with recurrent or metastatic STS after earlier treatments. CLINICAL IMPACT. Percutaneous cryoablation should be considered for local control of treatment-refractory STS.

Optimizing Morbidity in Unplanned Soft Tissue Sarcoma Excisions: Should We Skip the Reconstructive Ladder?

INTRODUCTION: Soft tissue sarcomas (STSs) are rare and diverse primary malignant tumors that comprise approximately 1% of all malignancies. Misdiagnoses and unplanned excisions of STSs are common due to the tumor's rarity, leading to secondary tumor bed excisions (TBEs). Reconstructive outcomes for TBEs remain poorly understood, prompting this study to address the knowledge gap and inform preoperative discussions. METHODS: This was a retrospective cohort study of patients who underwent STS excisions at a quaternary cancer center. Patients were categorized into mass excision (ME) and TBE groups. Reconstructive approaches were divided into simple (primary closure, complex repair, skin grafts, local flaps) and advanced (pedicled or free flaps). The groups were compared for postoperative outcomes, including complications, recurrence, and death. RESULTS: When simple reconstructive techniques were used, TBEs exhibited higher rates of overall and major complications, whereas MEs had higher rates of overall and minor complications. Intergroup analysis revealed that with simple reconstruction, rates of overall and major complications were higher in TBEs than in MEs, and rates of minor complications were higher in MEs than in TBEs. Regression analyses revealed that simple reconstruction of TBEs had 90% and 180% higher odds of major complications and reoperation compared to simple reconstruction of MEs ( P < 0.05). CONCLUSION: TBEs, despite their smaller size, exhibited a heightened susceptibility to overall and major complications, challenging the notion that simpler techniques suffice in these cases. Our findings encourage the consideration of advanced reconstructive techniques for TBEs that may seem amenable to simple reconstructive techniques.

Retrospective Analysis of Retroperitoneal-Abdominal-Pelvic Ganglioneuromas: An International Study by the Transatlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG).

OBJECTIVE: The Transatlantic Australasian Retroperitoneal Sarcoma Working Group conducted a retrospective study on the disease course and clinical management of ganglioneuromas. BACKGROUND: Ganglioneuromas are rare tumors derived from neural crest cells. Data on these tumors remain limited to case reports and single-institution case series. METHODS: Patients of all ages with pathologically confirmed primary retroperitoneal, intra-abdominal, and pelvic ganglioneuromas between January 1, 2000, and January 1, 2020, were included. We examined demographic, clinicopathologic, and radiologic characteristics, as well as clinical management. RESULTS: Overall, 328 patients from 29 institutions were included. The median age at diagnosis was 37 years with 59.1% of patients being female. Symptomatic presentation comprised 40.9% of cases, and tumors were often located in the extra-adrenal retroperitoneum (67.1%). At baseline, the median maximum tumor diameter was 7.2 cm. One hundred sixteen (35.4%) patients underwent active surveillance, whereas 212 (64.6%) patients underwent resection with 74.5% of operative cases achieving an R0/R1 resection. Serial tumor evaluations showed that malignant transformation to neuroblastoma was rare (0.9%, N=3). Tumors undergoing surveillance had a median follow-up of 1.9 years, with 92.2% of ganglioneuromas stable in size. With a median follow-up of 3.0 years for resected tumors, 84.4% of patients were disease free after resections, whereas recurrences were observed in 4 (1.9%) patients. CONCLUSIONS: Most ganglioneuromas have indolent disease courses and rarely transform to neuroblastoma. Thus, active surveillance may be appropriate for benign and asymptomatic tumors particularly when the risks of surgery outweigh the benefits. For symptomatic or growing tumors, resection may be curative.

Practice Pattern Variability in the Management of Regional Lymph Node Metastasis in Extremity and Trunk Soft Tissue Sarcoma: A Survey of the Society of Surgical Oncology and Musculoskeletal Tumor Society Membership.

BACKGROUND: Regional lymph node metastasis in extremity and trunk soft tissue sarcoma (ETSTS) is rare with no standardized management. We sought to determine management patterns for regional lymph node metastasis in ETSTS. METHODS: A survey regarding the management of ETSTS lymph node metastasis was distributed to the membership of the Musculoskeletal Tumor Society (MSTS) and the Society of Surgical Oncology (SSO) in January 2022. The survey queried the type of training (surgical oncology, orthopedic oncology), details of their practice setting, and management decisions of hypothetical ETSTS scenarios that involved potential or confirmed lymph node metastasis. RESULTS: The survey was distributed to 349 MSTS members (open rate of 63%, completion rate 21%) and 3026 SSO members (open rate of 55%, completion rate 4.7%) and was completed by 214 respondents, of whom 73 (34.1%) and 141 (65.9%) were orthopedic oncology and surgical oncology fellowship-trained, respectively. The majority of respondents practiced in an academic setting (n = 171, 79.9%) and treat >10 extremity sarcoma cases annually (n = 138, 62.2%). In scenarios with confirmed nodal disease for clear cell and epithelioid sarcoma, surgical oncologists were inclined to perform lymphadenectomy, while orthopedic oncologists were inclined to offer targeted lymph node excision with adjuvant radiation (p < 0.001). There was heterogeneity of responses regarding the management of nodal disease regardless of training background. CONCLUSION: Self-reported management of nodal disease in ETSTS was variable among respondent groups with differences and similarities based on training background. These data highlight the variability of practice for nodal disease management and the need for consensus-based guidelines.

Sentinel Lymph Node Biopsy for Extremity and Truncal Soft Tissue Sarcomas: A Systematic Review of the Literature.

BACKGROUND: Regional lymph node metastasis (RLNM) occurs infrequently in patients with soft tissue sarcoma (STS), although certain STS subtypes have a higher propensity for RLNM. The identification of RLNM has significant implications for staging and prognosis; however, the precise impact of node-positive disease on patient survival remains a topic of controversy. Although the benefits of sentinel lymph node biopsy (SLNB) are well documented in patients with melanoma and breast cancer, whether this procedure offers a benefit in STS is controversial. METHODS: A systematic literature search was performed and articles reviewed to determine if SLNB in patients with extremity/truncal STS impacts disease-free or overall survival. RESULTS: Six studies were included. Rates of sentinel lymph node positivity were heterogeneous (range 4.3-50%). The impact of SLNB on patient outcomes remains unclear. The overall quality of available evidence was low, as assessed by the Grading of Recommendations, Assessment, Development, and Evaluation system. CONCLUSIONS: The literature addressing the impact of nodal basin evaluation on the staging and management of patients with extremity/truncal STS is confounded by heterogeneous patient cohorts and clinical practices. Multicenter prospective studies are warranted to determine the true incidence of RLNM and whether SLNB could benefit patients with clinically occult RLNM at diagnosis.

Clinical Impact of External Beam Radiotherapy for Surgically Resected Primary Retroperitoneal Liposarcoma.

INTRODUCTION: EORTC-62092 (STRASS) was a phase 3, randomized study that compared surgery alone versus surgery plus neoadjuvant radiotherapy (RT) for retroperitoneal sarcomas. RT was not associated with improved abdominal recurrence-free survival, the primary outcome measure, although on subanalysis, there may have been benefit for well-differentiated (WD) liposarcoma. This study investigated the real-world use and outcomes of RT (neoadjuvant and adjuvant) for the management of retroperitoneal liposarcoma. METHODS: We queried the National Cancer Database (NCDB) (2004-2017) for patients with nonmetastatic, primary retroperitoneal liposarcoma treated with resection with or without RT (n = 3911). Patients were stratified by treatment type and histology [WD (n = 2252), dedifferentiated (DD) (n = 1659)]. Propensity score (PS) matching was used before comparison of treatment groups. Overall survival (OS) was the primary outcome measure. RESULTS: Median follow-up time was 4.1 years, and median OS was 10.7 years. There was no association between RT and OS for either WDLPS or DDLPS cohorts. We performed a subgroup analysis of neoadjuvant RT only, similar to STRASS. For WDLPS after PS matching (n = 208), neoadjuvant RT was not associated with OS (hazard ratio [HR] 1.01, p = 0.0523) but was associated with longer postoperative hospital stay (p = 0.012). For DDLPS after PS matching (n = 290), neoadjuvant RT was not associated with OS (HR 1.02, p = 0.889). For both WD-LPS and DD-LPS, utilization of neoadjuvant RT was associated with treatment at high-volume (≥ 10 cases/year) and academic/network facilities. CONCLUSIONS: For primary retroperitoneal liposarcoma treated with surgical resection, radiotherapy was not associated with an overall survival benefit in this propensity-matched, adjusted analysis of the NCDB.

Re-excision After Unplanned Excision of Soft Tissue Sarcoma is Associated with High Morbidity and Limited Pathologic Identification of Residual Disease.

BACKGROUND: Patients with unplanned excision (UPE) of trunk and extremity soft tissue sarcoma (STS) present a significant management challenge for sarcoma specialists. Oncologic re-resection has been considered standard practice after UPE with positive or uncertain margins. A strategy of active surveillance or "watch and wait" has been suggested as a safe alternative to routine re-excision. In this context, the current study sought to evaluate short-term outcomes and morbidity after re-resection to better understand the risks and benefits of this treatment strategy. METHODS: A retrospective, single-institution study reviewed patients undergoing oncologic re-resection after UPE of an STS during a 5-year period (2015-2020), excluding those with evidence of gross residual disease. Short-term clinical outcomes were evaluated together with final pathologic findings. RESULTS: The review identified 67 patients undergoing re-resection after UPE of an STS. Of these 67 patients, 45 (67%) were treated with a combination of external beam radiation therapy (EBRT) and surgery. Plastic surgery was involved for reconstruction in 49 cases (73%). The rate of wound complications after re-resection was 45 % (n = 30), with 15 % (n = 10) of the patients experiencing a major wound complication. Radiation therapy and plastic surgery involvement were independently associated with wound complications. Notably, 45 patients (67%) had no evidence of residual disease in the re-resection specimen, whereas 13 patients (19 %) had microscopic disease, and 9 patients (13%) had indeterminate pathology. CONCLUSION: Given the morbidity of re-resection and limited identification of residual disease, treatment plans and discussions with patients should outline the expected pathologic findings and morbidity of surgery.

Hypofractionated, 3-week, preoperative radiotherapy for patients with soft tissue sarcomas (HYPORT-STS): a single-centre, open-label, single-arm, phase 2 trial.

BACKGROUND: The standard preoperative radiotherapy regimen of 50 Gy delivered in 25 fractions for 5 weeks for soft tissue sarcomas results in excellent local control, with major wound complications occurring in approximately 35% of patients. We aimed to investigate the safety of a moderately hypofractionated, shorter regimen of radiotherapy, which could be more convenient for patients. METHODS: This single-centre, open-label, single-arm, phase 2 trial (HYPORT-STS) was done at a single tertiary cancer care centre (MD Anderson Cancer Center, Houston, TX, USA). We administered preoperative radiotherapy to a dose of 42·75 Gy in 15 fractions of 2·85 Gy/day for 3 weeks (five fractions per week) to adults (aged ≥18 years) with non-metastatic soft tissue sarcomas of the extremities or superficial trunk and an Eastern Cooperative Oncology Group performance status of 0-3. The primary endpoint was a major wound complication occurring within 120 days of surgery. Major wound complications were defined as those requiring a secondary operation, or operations, under general or regional anaesthesia for wound treatment; readmission to the hospital for wound care; invasive procedures for wound care; deep wound packing to an area of wound measuring at least 2 cm in length; prolonged dressing changes; repeat surgery for revision of a split thickness skin graft; or wet dressings for longer than 4 weeks. We analysed our primary outcome and safety in all patients who enrolled. We monitored safety using a Bayesian, one-arm, time-to-event stopping rule simulator comparing the rate of major wound complications at 120 days post-surgery among study participants with the historical rate of 35%. This trial is registered with ClinicalTrials.gov, NCT03819985, recruitment is complete, and follow-up continues. FINDINGS: Between Dec 18, 2018, and Jan 6, 2021, we assessed 157 patients for eligibility, of whom 120 were enrolled and received hypofractionated preoperative radiotherapy. At no time did the stopping rule computation indicate that the trial should be stopped early for lack of safety. Median postoperative follow-up was 24 months (IQR 17-30). Of 120 patients, 37 (31%, 95% CI 24-40) developed a major wound complication at a median time of 37 days (IQR 25-59) after surgery. No patient had acute radiation toxicity (during radiotherapy or within 4 weeks of the radiotherapy end date) of grade 3 or worse (Common Terminology Criteria for Adverse Events [CTCAE] version 4.0) or an on-treatment serious adverse event. Four (3%) of 115 patients had late radiation toxicity (≥6 months post-surgery) of at least grade 3 (CTCAE or Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer Late Radiation Morbidity Scoring Scheme): femur fractures (n=2), lymphoedema (n=1), and skin ulceration (n=1). There were no treatment-related deaths. INTERPRETATION: Moderately hypofractionated preoperative radiotherapy delivered to patients with soft tissue sarcomas was safe and could therefore be a more convenient alternative to conventionally fractionated radiotherapy. Patients can be counselled about these results and potentially offered this regimen, particularly if it facilitates care at a sarcoma specialty centre. Results on long-term oncological, late toxicity, and functional outcomes are awaited. FUNDING: The National Cancer Institute.

Durvalumab plus tremelimumab in advanced or metastatic soft tissue and bone sarcomas: a single-centre phase 2 trial.

BACKGROUND: Few standard treatment options are available for patients with metastatic sarcomas. We did this trial to evaluate the efficacy, safety, and changes in the tumour microenvironment for durvalumab, an anti-PD-L1 drug, and tremelimumab, an anti-CTLA-4 drug, across multiple sarcoma subtypes. METHODS: In this single-centre phase 2 trial, done at The University of Texas MD Anderson Cancer Center (Houston, TX USA), patients aged 18 years or older with advanced or metastatic sarcoma with an Eastern Cooperative Oncology Group performance status of 0 or 1 who had received at least one previous line of systemic therapy were enrolled in disease subtype-specific groups (liposarcoma, leiomyosarcoma, angiosarcoma, undifferentiated pleomorphic sarcoma, synovial sarcoma, osteosarcoma, alveolar soft-part sarcoma, chordoma, and other sarcomas). Patients received 1500 mg intravenous durvalumab and 75 mg intravenous tremelimumab for four cycles, followed by durvalumab alone every 4 weeks for up to 12 months. The primary endpoint was progression-free survival at 12 weeks in the intention-to-treat population (all patients who received at least one dose of treatment). Safety was also analysed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02815995, and is completed. FINDINGS: Between Aug 17, 2016, and April 9, 2018, 62 patients were enrolled, of whom 57 (92%) received treatment and were included in the intention-to-treat population. With a median follow-up of 37·2 months (IQR 1·8-10·1), progression-free survival at 12 weeks was 49% (95% CI 36-61). 21 grade 3-4 treatment-related adverse events were reported, the most common of which were increased lipase (four [7%] of 57 patients), colitis (three [5%] patients), and pneumonitis (three [5%] patients). Nine (16%) patients had a treatment related serious adverse event. One patient had grade 5 pneumonitis and colitis. INTERPRETATION: The combination of durvalumab and tremelimumab is an active treatment regimen for advanced or metastatic sarcoma and merits evaluation in specific subsets in future trials. FUNDING: AstraZeneca.

Real-world use of palbociclib monotherapy in retroperitoneal liposarcomas at a large volume sarcoma center.

Palbociclib has been evaluated in early phase trials for well-differentiated liposarcoma (WDLPS) and dedifferentiated liposarcoma (DDLPS) patients, with reported median progression-free survival (PFS) of 18 weeks. Here, we report on real-world use and surgical outcomes associated with palbociclib treatment. We retrospectively reviewed 61 consecutive patients with retroperitoneal WDLPS (n = 14) or DDLPS (n = 47) treated with palbociclib monotherapy between 1 March 2016 and 28 February 2021 at The University of Texas MD Anderson Cancer Center. At palbociclib initiation, median age was 64 (interquartile range [IQR] 56-72). In WDLPS and DDLPS cohorts, the median number of prior systemic treatments was 0 (IQR 0-0) and 2 (IQR 0-4), respectively. Median number of prior surgeries was 2 (WDLPS IQR 1-2.75) and 2 (DDLPS IQR 1-3). Median PFS was 9.2 (WDLPS IQR 3.9-21.9) and 2.6 months (DDLPS IQR 2.0-6.1), with median time on treatment of 7.4 months (WDLPS IQR 3.5-14.2) and 2.7 months (DDLPS IQR 2.0-5.7). Twelve patients ultimately underwent surgical resection. Resections were macroscopically complete (R0/R1) in half (n = 6/12), among whom only one patient experienced relapse after resection (median follow-up 7.5 months). All patients who underwent macroscopically incomplete resections progressed after surgery with median time to progression of 3.3 months (IQR 2.3-4.4). Surgery after palbociclib treatment was not associated with improved overall survival. Efficacy of palbociclib monotherapy for patients with advanced WDLPS and DDLPS is disappointing. While palbociclib may have been used to delay surgery, there was no clear benefit from treatment and few patients achieved prolonged tumor control.

Sentinel Lymph Node Biopsy and Formal Lymphadenectomy for Soft Tissue Sarcoma: A Single Center Experience of 86 Consecutive Cases.

BACKGROUND: Lymph node metastases (LNMs) are rare in patients with soft tissue sarcoma (STS), and there is limited evidence to guide clinical management. We describe our experience with sentinel lymph node biopsy (SLNB) and lymphadenectomy in STS patients. METHODS: A single-center, retrospective review was performed for patients with STS treated with SLNB and/or lymphadenectomy from 1994 to 2018. Clinicopathologic characteristics, multimodality treatment, regional/distant recurrence-free survival (RFS), and overall survival (OS) were examined. RESULTS: Eighty-six patients underwent SLNB (n = 34) and/or lymphadenectomy (n = 60) for STS. The most frequent histologic subtypes were epithelioid, clear cell, and undifferentiated pleomorphic sarcoma. Eight of 34 (23.5%) patients had a positive SLNB with 5-year OS of 71.4% compared with 71.9% for those with a negative SLNB. Eight of the 26 SLN-negative patients (30.8%) eventually developed nodal recurrence (n = 2) and/or (n = 6) distant metastasis with an estimated 5-year OS of 50%. Of patients undergoing lymphadenectomy, estimated 5-year OS was 44.6% and median RFS was 12 months. Eight (13.3%) had distant disease at time of lymphadenectomy, 20 (33.3%) developed distant recurrence after lymphadenectomy, and 6 (10%) developed regional-only recurrence. Patients with regional-only recurrence after lymphadenectomy had an estimated 5-year OS of 66.7% compared with 29.1% for those who recurred distantly. CONCLUSIONS: Patients with positive SLNB had similar survival to those with negative SLNB. Lymphadenectomy for isolated nodal disease is associated with poor RFS but reasonable 5-year OS when recurrence is regional-only. In STS, regional disease appears clinically distinct from distant metastatic disease and has better outcomes.

Sarculator is a Good Model to Predict Survival in Resected Extremity and Trunk Sarcomas in US Patients.

BACKGROUND: Sarculator is an online validated nomogram that predicts overall survival of patients with resected, primary extremity sarcomas. However, its ability to accurately predict outcomes in US patients with sarcoma is unknown. PATIENTS AND METHODS: Patients from the National Cancer Data Base (NCDB) (2006-2016) with resected stage I-III primary extremity or trunk sarcoma were included. Predicted overall survival (pOS) was calculated using the Sarculator algorithm, which includes patient age, tumor size (cm), grade (1-3), and histology, and compared with actual overall survival (aOS). Harrell's C-index was calculated to determine the discriminatory ability of Sarculator (0.7 = good, 0.8 = strong, 1.0 = perfect model), and calibration plots were created. RESULTS: In total, 9738 patients were included. Five-year pOS was 73.7% compared with aOS of 68.9%. The C-index for the entire cohort was 0.726. By stage, the C-index was 0.730 for stage I, 0.708 for stage II, and 0.679 for stage III. By histology, C-indices were highest for leiomyosarcoma (0.745), myxofibrosarcoma (0.722), and other histologies (0.721). By sociodemographic variables, Sarculator performed better for patients < 50 years (C-index 0.722), of other/unknown race (C-index 0.781), with private insurance (C-index 0.715), treated at a center other than a community cancer programs (C-index > 0.7), and with no comorbidities (C-index 0.716). Outcomes by zip code educational attainment and income were not markedly different (all C-indices > 0.7). CONCLUSIONS: Sarculator is overall a good predictor of aOS and useful tool for clinicians to aid in survival prognostication. However, clinicians should be aware of populations for whom Sarculator's predictions may be less accurate. Future work could focus on enhancing the Sarculator algorithm specifically for US patients by including demographic variables.