Follow-up strategies for patients with gastrointestinal stromal tumour treated with or without adjuvant imatinib after surgery

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What clinical trials are needed for treatment of leiomyosarcoma?

Leiomyosarcoma is one of the most common subtypes of soft tissue sarcomas accounting for approximately 20% of sarcomas. As leiomyosarcoma patients frequently develop metastatic disease, effective systemic therapies are needed to improve clinical outcomes. The overall activity of the currently available conventional systemic therapies and the prognosis of patients with advanced and/or metastatic disease are poor. As such, the treatment of this patient population remains challenging. As a result, there is a clear unmet medical need, and designing and performing meaningful clinical studies are of utmost importance to improve the prognosis of this patient group. Therefore, the aim of this review is to briefly summarize state-of-the-art treatments for leiomyosarcoma patients and to describe trial characteristics needed for informative clinical studies

Nivolumab and sunitinib combination in advanced soft tissue sarcomas : A multicenter, single-arm, phase Ib/II trial

Sarcomas exhibit low expression of factors related to immune response, which could explain the modest activity of PD-1 inhibitors. A potential strategy to convert a cold into an inflamed microenvironment lies on a combination therapy. As tumor angiogenesis promotes immunosuppression, we designed a phase Ib/II trial to test the double inhibition of angiogenesis (sunitinib) and PD-1/PD-L1 axis (nivolumab). This single-arm, phase Ib/II trial enrolled adult patients with selected subtypes of sarcoma. Phase Ib established two dose levels: level 0 with sunitinib 37.5 mg daily from day 1, plus nivolumab 3 mg/kg intravenously on day 15, and then every 2 weeks; and level-1 with sunitinib 37.5 mg on the first 14 days (induction) and then 25 mg per day plus nivolumab on the same schedule. The primary endpoint was to determine the recommended dose for phase II (phase I) and the 6-month progression-free survival rate, according to Response Evaluation Criteria in Solid Tumors 1.1 (phase II). From May 2017 to April 2019, 68 patients were enrolled: 16 in phase Ib and 52 in phase II. The recommended dose of sunitinib for phase II was 37.5 mg as induction and then 25 mg in combination with nivolumab. After a median follow-up of 17 months (4-26), the 6-month progression-free survival rate was 48% (95% CI 41% to 55%). The most common grade 3-4 adverse events included transaminitis (17.3%) and neutropenia (11.5%). Sunitinib plus nivolumab is an active scheme with manageable toxicity in the treatment of selected patients with advanced soft tissue sarcoma, with almost half of patients free of progression at 6 months

Gene expression analyses determine two different subpopulations in KIT-negative GIST-like (KNGL) patients

Introduction: There are limited findings available on KIT-negative GIST-like (KNGL) population. Also, KIT expression may be post-transcriptionally regulated by miRNA221 and miRNA222. Hence, the aim of this study is to characterize KNGL population, by differential gene expression, and to analyze miRNA221/222 expression and their prognostic value in KNGL patients. Methods: KIT, PDGFRA, DOG1, IGF1R, MIR221 and MIR222 expression levels were determined by qRT-PCR. We also analyzed KIT and PDGFRA mutations, DOG1 expression, by immunohistochemistry, along with clinical and pathological data. Disease-free survival (DFS) and overall survival (OS) differences were calculated using Log-rank test. Results: Hierarchical cluster analyses from gene expression data identified two groups: group I had KIT, DOG1 and PDGFRA overexpression and IGF1R underexpression and group II had overexpression of IGF1R and low expression of KIT, DOG1 and PDGFRA. Group II had a significant worse OS (p = 0.013) in all the series, and showed a tendency for worse OS (p = 0.11), when analyzed only the localized cases. MiRNA222 expression was significantly lower in a control subset of KIT-positive GIST (p < 0.001). OS was significantly worse in KNGL cases with higher expression of MIR221 (p = 0.028) or MIR222 (p = 0.014). Conclusions: We identified two distinct KNGL subsets, with a different prognostic value. Increased levels of miRNA221/222, which are associated with worse OS, could explain the absence of KIT protein expression of most KNGL tumors

Trabectedin and RAdiotherapy in Soft Tissue Sarcoma (TRASTS): Results of a Phase I Study in Myxoid Liposarcoma from Spanish (GEIS), Italian (ISG), French (FSG) Sarcoma Groups

Background: Myxoid liposarcoma (ML) exhibits a special sensitivity to trabectedin (T) and radiation therapy (RT). Preclinical data suggest a synergistic effect. We aimed to study safety, feasibility and activity of the administration of pre-operative concurrent T and RT in patients affected by localized resectable ML. Methods: Patients received 3 cycles (C) of T in combination with RT (45 Gy) in 25 fractions (1.8 Gy/fraction). Dose Levels for T were: 12 1 (1.1 mg/m2), 0 (1.3 mg/m2) and 1 (1.5 mg/m2). Primary endpoint was safety; antitumor activity was assessed by RECIST and Choi criteria. This study is registered at ClinicalTrials.gov, number NCT02275286. The phase 1 part of the study is complete and phase 2 is ongoing. Findings: From February 2015 to May 2016, 14 patients (M/F 7/7), median age 36 years (range 24\u201370) and median tumor size 12.5 cm (range 7\u201317 cm), were enrolled. One dose limiting toxicity (G3 transaminitis) occurred at Level 0 and one (sepsis due to catheter infection) at Level 1. All patients completed RT. Five patients achieved PR (36%), 8 SD (57%), 1 distant PD (7%) by RECIST, while 12 achieved PR (86%), 1 SD (7%) and 1 distant PD (7%) by Choi criteria. Twelve patients underwent surgery. Median viable residual tumor was 5% (0\u201360). Interpretation: T in combination with RT showed a favorable safety profile and antitumor activity in localized ML. T dose of 1.5 mg/m2 is the recommended dose for the phase 2 study, which is ongoing. Funding: This study was partially supported by Pharmamar

An update on the management of sporadic desmoid-type fibromatosis: A European Consensus Initiative between Sarcoma PAtients EuroNet (SPAEN) and European Organization for Research and Treatment of Cancer (EORTC)/Soft Tissue and Bone Sarcoma Group (STBSG)

Desmoid-type fibromatosis is a rare and locally aggressive monoclonal, fibroblastic proliferation characterized by a variable and often unpredictable clinical course. Currently, there is no established or evidence-based treatment approach available for this disease. Therefore, in 2015 the European Desmoid Working Group published a position paper giving recommendations on the treatment of this intriguing disease. Here, we present an update of this consensus approach based on professionals' AND patients' expertise following a round table meeting bringing together sarcoma experts from the European Organization for Research and Treatment of Cancer/Soft Tissue and Bone Sarcoma Group with patients and patient advocates from Sarcoma PAtients EuroNet. In this paper, we focus on new findings regarding the prognostic value of mutational analysis in desmoid-type fibromatosis patients and new systemic treatment options

The role of mutational analysis of KIT and PDGFRA in gastrointestinal stromal tumors in a clinical setting

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. Most GIST harbor a mutation affecting either the KIT or PDGFRA genes, whereas a small subgroup of tumors is wild type for mutations

Adjuvant Imatinib in Patients with GIST Harboring Exon 9 KIT Mutations : Results from a Multi-institutional European Retrospective Study

Purpose: The effect of high-dose imatinib (800 mg/day) on survival in the adjuvant treatment of patients with resected KIT exon 9-mutated gastrointestinal stromal tumors (GIST) is not established. Here, the association of dose and other clinicopatho-logic variables with survival was evaluated in a large multi-institutional European cohort. Experimental Design: Data from 185 patients were retrospec-tively collected in 23 European GIST reference centers. Propen-sity score matching (PSM) and inverse-probability of treatment weighting (IPTW) were used to account for confounders. Uni-variate and multivariate unweighted and weighted Cox propor-tional hazard regression models were estimated for relapse-free survival (RFS), modified-RFS (mRFS) and imatinib failure-free survival (IFFS). Univariate Cox models were estimated for overall survival. Results: Of the 185 patients, 131 (70.8%) received a starting dose of 400 mg/d and the remaining 54 (29.2%) a dose of 800 mg/d. Baseline characteristics were partially unbalanced, suggesting a potential selection bias. PSM and IPTW analyses showed no advantage of imatinib 800 mg/d. In the weighted multivariate Cox models, high-dose imatinib was not associated with the survival outcomes [RFS: hazard ratio (HR), 1.24; 95% confidence interval (CI), 0.79-1.94; mRFS: HR, 1.69; 95% CI, 0.92-3.10; IFFS: HR, 1.35; 95% CI, 0.79- 2.28]. The variables consistently associated with worse survival out-comes were high mitotic index and nongastric tumor location. Conclusions: In this retrospective series of patients with KIT exon 9-mutated GIST treated with adjuvant imatinib, a daily dose of 800 mg versus 400 mg did not show better results in terms of survival outcomes. Prospective evaluation of the more appropriate adjuvant treatment in this setting is warranted.Peer reviewe