Background: In ultra-rare sarcomas (URS) the conduction of prospective, randomized trials is challenging. Data from retrospective observational studies (ROS) may represent the best evidence... Show moreBackground: In ultra-rare sarcomas (URS) the conduction of prospective, randomized trials is challenging. Data from retrospective observational studies (ROS) may represent the best evidence available. ROS implicit limitations led to poor acceptance by the scientific community and regulatory authorities. In this context, an expert panel from the Connective Tissue Oncology Society (CTOS), agreed on the need to establish a set of minimum requirements for conducting high-quality ROS on the activity of systemic therapies in URS. Methods: Representatives from > 25 worldwide sarcoma reference centres met in November 2020 and identified a list of topics summarizing the main issues encountered in ROS on URS. An online survey on these topics was distributed to the panel; results were summarized by descriptive statistics and discussed during a second meeting (November 2021). Results: Topics identified by the panel included the use of ROS results as external control data, the criteria for contributing centers selection, modalities for ensuring a correct pathological diagnosis and radiologic assessment, consistency of surveillance policies across centers, study end-points, risk of data duplication, results publication. Based on the answers to the survey (55 of 62 invited experts) and discussion the panel agreed on 18 statements summarizing principles of recommended practice. Conclusions: These recommendations will be disseminated by CTOS across the sarcoma community and incorporated in future ROS on URS, to maximize their quality and favor their use as control data when results from prospective studies are unavailable. These recommendations could help the optimal conduction of ROS also in other rare tumors. Show less
Tenosynovial giant cell tumors (TGCT), are rare colony stimulating factor-1(CSF-1)-driven proliferative disorders affecting joints. Diffuse-type TGCT often causes significant morbidity due to local... Show moreTenosynovial giant cell tumors (TGCT), are rare colony stimulating factor-1(CSF-1)-driven proliferative disorders affecting joints. Diffuse-type TGCT often causes significant morbidity due to local recurrences necessitating multiple surgeries. Imatinib mesylate (IM) blocks the CSF-1 receptor. This study investigated the long term effects of IM in TGCT. We conducted an international multi-institutional retrospective study to assess the activity of IM: data was collected anonymously from individual patients with locally advanced, recurrent or metastatic TGCT. Sixty-two patients from 12 institutions across Europe, Australia and the United States were identified. Four patients with metastatic TGCT progressed rapidly on IM and were excluded for further analyses. Seventeen of 58 evaluable patients achieved complete response (CR) or partial response (PR). One- and five-year progression-free survival rates were 71% and 48%, respectively. Thirty-eight (66%) patients discontinued IM after a median of 7 (range 1-80) months. Reported adverse events in 45 (78%) patients were among other edema (48%) and fatigue (50%), mostly grade 1-2 (89%). Five patients experienced grade 3-4 toxicities. This study confirms, with additional follow-up, the efficacy of IM in TGCT. In responding cases we confirmed prolonged IM activity on TGCT symptoms even after discontinuation, but with high rates of treatment interruption and additional treatments. Show less
Frezza, A.M.; Assi, T.; Vullo, S. lo; Ben-Ami, E.; Dufresne, A.; Yonemori, K.; ... ; Stacchiotti, S. 2019
Background Intimal sarcoma (InS) is an exceedingly rare neoplasm with an unfavorable prognosis, for which new potentially active treatments are under development. We report on the activity of... Show moreBackground Intimal sarcoma (InS) is an exceedingly rare neoplasm with an unfavorable prognosis, for which new potentially active treatments are under development. We report on the activity of anthracycline-based regimens, gemcitabine-based regimens, and pazopanib in patients with InS. Methods Seventeen sarcoma reference centers in Europe, the United States, and Japan contributed data to this retrospective analysis. Patients with MDM2-positive InS who were treated with anthracycline-based regimens, gemcitabine-based regimens, or pazopanib between October 2001 and January 2018 were selected. Local pathological review was performed to confirm diagnosis. Response was assessed by RECIST1.1. Recurrence-free survival (RFS), progression-free survival (PFS) and overall survival were computed by Kaplan-Meier method. Results Seventy-two patients were included (66 anthracycline-based regimens; 26 gemcitabine-based regimens; 12 pazopanib). In the anthracycline-based group, 24 (36%) patients were treated for localized disease, and 42 (64%) patients were treated for advanced disease. The real-world overall response rate (rwORR) was 38%. For patients with localized disease, the median RFS was 14.6 months. For patients with advanced disease, the median PFS was 7.7 months. No anthracycline-related cardiac toxicity was reported in patients with cardiac InS (n = 26). For gemcitabine and pazopanib, the rwORR was 8%, and the median PFS was 3.2 and 3.7 months, respectively. Conclusion This retrospective series shows the activity of anthracycline-based regimens in InS. Of note, anthracyclines were used in patients with cardiac InS with no significant cardiac toxicity. The prognosis in patients with InS remains poor, and new active drugs and treatment strategies are needed. Show less
Background Ontuxizumab, a humanized monoclonal antibody, targets endosialin (tumor endothelial marker 1 [TEM-1] or CD248), which is expressed on sarcoma cells and is believed to be involved in... Show moreBackground Ontuxizumab, a humanized monoclonal antibody, targets endosialin (tumor endothelial marker 1 [TEM-1] or CD248), which is expressed on sarcoma cells and is believed to be involved in tumor angiogenesis. This is the first trial to evaluate ontuxizumab in patients with sarcoma. Methods Part 1 was an open-label, dose-finding, safety lead-in: 4, 6, or 8 mg/kg with gemcitabine and docetaxel (G/D; 900 mg/m(2) gemcitabine on days 1 and 8 and 75 mg/m(2) docetaxel on day 8). In part 2, patients were randomized in a double-blind fashion in 2:1 ratio to ontuxizumab (8 mg/kg) or a placebo with G/D. Randomization was stratified by 4 histological cohorts. Results In part 2 with 209 patients, no significant difference in progression-free survival between ontuxizumab plus G/D (4.3 months; 95% confidence interval [CI], 2.7-6.3 months) and the placebo plus G/D (5.6 months; 95% CI, 2.6-8.3 months) was observed (P = .67; hazard ratio [HR], 1.07; 95% CI, 0.77-1.49). Similarly, there was no significant difference in median overall survival between the 2 groups: 18.3 months for the ontuxizumab plus G/D group (95% CI, 16.2-21.1 months) and 21.1 months for the placebo plus G/D group (95% CI, 14.2 months to not reached; P = .32; HR, 1.23; 95% CI, 0.82-1.82). No significant differences between the treatment groups occurred for any efficacy parameter by sarcoma cohort. The combination of ontuxizumab plus G/D was generally well tolerated. Conclusions Ontuxizumab plus G/D showed no enhanced activity over chemotherapy alone in soft-tissue sarcomas, whereas the safety profile of the combination was consistent with G/D alone. Show less
