Circulating Tumor Cells and Biomarker Modulation with Olaratumab Monotherapy Followed by Olaratumab plus Doxorubicin: Phase Ib Study in Patients with Soft-Tissue Sarcoma.

This phase Ib study enumerated whole blood circulating tumor cells (CTC) and evaluated biomarkers in patients with potentially resectable soft-tissue sarcoma (STS) treated with olaratumab monotherapy (20 mg/kg) for one cycle followed by up to six cycles of olaratumab (20 mg/kg, cycles 1-2; 15 mg/kg, cycles 3-7) plus doxorubicin (75 mg/m2 on day 1). CTCs, platelet-derived growth factor receptors (PDGFR), and PDGF ligand expression in tumor tissue pre- and post-olaratumab monotherapy were evaluated. Antitumor activity, safety, pharmacokinetics, and PET/biomarker association with clinical outcome were assessed. Of 51 treated patients, 35, 43, and 37 were evaluable for CTC enumeration, PDGFRs, and PDGF ligand expression, respectively. An increase in CTCs at cycle 1 day 8 was observed, followed by a significant reduction by cycle 3 day 1 or 30-day follow-up. Decrease in CTC counts after olaratumab monotherapy was higher in patients with disease control than without disease control (57.9% vs. 31.2%). Baseline IHC expression was positive in most patients for PDGFRα [n = 31 (72.1%)] and PDGFRß [n = 36 (83.7%)]. Similar rates were observed post-olaratumab monotherapy [PDGFRα, n = 30 (69.8%); PDGFRß, n = 33 (76.7%)]. Eleven patients (29.7%) showed a 30% reduction by RT-PCR in PDGFRα at cycle 2. PDGFR expression and PET response showed no correlation with clinical outcome. Safety and pharmacokinetic profiles were consistent with previous reports. This study, the first to use a validated method for CTC detection, confirms that CTC enumeration in STS is feasible. However, no correlation was observed between PDGFRα expression and clinical outcome.

Pexidartinib Long-Term Hepatic Safety Profile in Patients with Tenosynovial Giant Cell Tumors.

BACKGROUND: Pexidartinib is approved in the U.S. for tenosynovial giant cell tumors (TGCTs). Herein, we assessed the hepatic safety profile of pexidartinib across patients with TGCTs receiving pexidartinib. MATERIALS, AND METHODS: Hepatic adverse reactions (ARs) were assessed by type and magnitude of liver test abnormalities, classified as (a) isolated aminotransferase elevations (alanine [ALT] or aspartate [AST], without significant alkaline phosphatase [ALP] or bilirubin elevations), or (b) mixed or cholestatic hepatotoxicity (increase in ALP with or without ALT/AST and bilirubin elevations, based on adjudication). Median follow-up from initial pexidartinib treatment was 39 months (range, 32-82) in 140 patients with TGCTs across clinical studies NCT01004861, NCT02371369, NCT02734433, and NCT03291288. RESULTS: In total, 95% of patients with TGCTs (133/140) treated with pexidartinib (median duration of exposure, 19 months [range, 1-76]), experienced a hepatic AR. A total of 128 patients (91%) had reversible, low-grade dose-dependent isolated AST/ALT elevations without significant ALP elevations. Five patients (4%) experienced serious mixed or cholestatic injury. No case met Hy's law criteria. Onset of hepatic ARs was predominantly in the first 2 months. All five serious hepatic AR cases recovered 1-7 months following pexidartinib discontinuation. Five patients from the non-TGCT population (N = 658) experienced serious hepatic ARs, two irreversible cases. CONCLUSION: This pooled analysis provides information to help form the basis for the treating physician's risk assessment for patients with TCGTs, a locally aggressive but typically nonmetastatic tumor. In particular, long-term treatment with pexidartinib has a predictable effect on hepatic aminotransferases and unpredictable risk of serious cholestatic or mixed liver injury. IMPLICATIONS FOR PRACTICE: This is the first long-term pooled analysis to report on the long-term hepatic safety of pexidartinib in patients with tenosynovial giant cell tumors associated with severe morbidity or functional limitations and not amenable to improvement with surgery. These findings extend beyond what has been previously published, describing the observed instances of hepatic toxicity following pexidartinib treatment across the clinical development program. This information is highly relevant for medical oncologists and orthopedic oncologists and provides guidance for its proper use for appropriate patients within the Pexidartinib Risk Evaluation and Mitigation Safety program.

Dovitinib in patients with gastrointestinal stromal tumour refractory and/or intolerant to imatinib.

BACKGROUND: This multicentre phase II trial (DOVIGIST) evaluated the antitumour activity of dovitinib as second-line treatment of patients with gastrointestinal stromal tumour (GIST) refractory to imatinib or who do not tolerate imatinib. METHODS: Patients received oral dovitinib 500 mg day-1, 5 days on/2 days off, until GIST progression or unacceptable toxicity, with an objective to evaluate efficacy, assessed as the disease control rate (DCR) at 12 weeks. Tumour assessment and response to dovitinib therapy were evaluated by Response Evaluation Criteria In Solid Tumours (RECIST v1.1) and the Choi criteria. Secondary objectives included assessment of progression-free survival (PFS), safety and tolerability, and DCR at the end of treatment. RESULTS: Thirty-eight of the 39 patients enrolled had histologically confirmed GIST. The DCR at 12 weeks was 52.6% (90% confidence interval (CI), 38.2-66.7%) meeting the preset efficacy criterion for the primary end point. The objective response rate (complete response+partial response) was 2.6% (1 of 38; 90% CI, 0.1-11.9%), and 5.3% (n=2; 90% CI, 0.9-15.7%) at the end of the study. The median PFS was 4.6 months (90% CI, 2.8-7.4 months). Dose interruption was required in 26 patients (66.7%), of which 18 (69.2%) were due to adverse events. The most frequently observed grade 3 adverse events included hypertension (n=7), fatigue (n=5), vomiting (n=4), hypertriglyceridaemia (n=4), and γ-glutamyltransferase increase (n=4). CONCLUSIONS: Dovitinib is an active treatment for patients with GIST who are intolerant to imatinib or whose GIST progresses on imatinib.

Histotype-tailored neoadjuvant chemotherapy versus standard chemotherapy in patients with high-risk soft-tissue sarcomas (ISG-STS 1001): an international, open-label, randomised, controlled, phase 3, multicentre trial.

BACKGROUND: Previous trials from our group suggested an overall survival benefit with five cycles of adjuvant full-dose epirubicin plus ifosfamide in localised high-risk soft-tissue sarcoma of the extremities or trunk wall, and no difference in overall survival benefit between three cycles versus five cycles of the same neoadjuvant regimen. We aimed to show the superiority of the neoadjuvant administration of histotype-tailored regimen to standard chemotherapy. METHODS: For this international, open-label, randomised, controlled, phase 3, multicentre trial, patients were enrolled from 32 hospitals in Italy, Spain, France, and Poland. Eligible patients were aged 18 years or older with localised, high-risk (high malignancy grade, 5 cm or longer in diameter, and deeply located according to the investing fascia), soft-tissue sarcoma of the extremities or trunk wall and belonging to one of five histological subtypes: high-grade myxoid liposarcoma, leiomyosarcoma, synovial sarcoma, malignant peripheral nerve sheath tumour, and undifferentiated pleomorphic sarcoma. Patients were randomly assigned (1:1) to receive three cycles of full-dose standard chemotherapy (epirubicin 60 mg/m2 per day [short infusion, days 1 and 2] plus ifosfamide 3 g/m2 per day [days 1, 2, and 3], repeated every 21 days) or histotype-tailored chemotherapy: for high-grade myxoid liposarcoma, trabectedin 1·3 mg/m2 via 24-h continuous infusion, repeated every 21 days; for leiomyosarcoma, gemcitabine 1800 mg/m2 on day 1 intravenously over 180 min plus dacarbazine 500 mg/m2 on day 1 intravenously over 20 min, repeated every 14 days; for synovial sarcoma, high-dose ifosfamide 14 g/m2, given over 14 days via an external infusion pump, every 28 days; for malignant peripheral nerve sheath tumour, intravenous etoposide 150 mg/m2 per day (days 1, 2, and 3) plus intravenous ifosfamide 3 g/m2 per day (days 1, 2, and 3), repeated every 21 days; and for undifferentiated pleomorphic sarcoma, gemcitabine 900 mg/m2 on days 1 and 8 intravenously over 90 min plus docetaxel 75 mg/m2 on day 8 intravenously over 1 h, repeated every 21 days. Randomisation was stratified by administration of preoperative radiotherapy and by country of enrolment. Computer-generated random lists were prepared by use of permuted balanced blocks of size 4 and 6 in random sequence. An internet-based randomisation system ensured concealment of the treatment assignment until the patient had been registered into the system. No masking of treatment assignments was done. The primary endpoint was disease-free survival. The primary and safety analyses were planned in the intention-to-treat population. We did yearly futility analyses on an intention-to-treat basis. The study was registered with ClinicalTrials.gov, number NCT01710176, and with the European Union Drug Regulating Authorities Clinical Trials, number EUDRACT 2010-023484-17, and is closed to patient entry. FINDINGS: Between May 19, 2011, and May 13, 2016, 287 patients were randomly assigned to a group (145 to standard chemotherapy and 142 to histotype-tailored chemotherapy), all of whom, except one patient assigned to standard chemotherapy, were included in the efficacy analysis (97 [34%] with undifferentiated pleomorphic sarcoma; 64 [22%] with high-grade myxoid liposarcoma; 70 [24%] with synovial sarcoma; 27 [9%] with malignant peripheral nerve sheath tumour; and 28 [10%] with leiomyosarcoma). At the third futility analysis, with a median follow-up of 12·3 months (IQR 2·75-28·20), the projected disease-free survival at 46 months was 62% (95% CI 48-77) in the standard chemotherapy group and 38% (22-55) in the histotype-tailored chemotherapy group (stratified log-rank p=0·004; hazard ratio 2·00, 95% CI 1·22-3·26; p=0·006). The most common grade 3 or higher adverse events in the standard chemotherapy group (n=125) were neutropenia (107 [86%]), anaemia (24 [19%]), and thrombocytopenia (21 [17%]); the most common grade 3 or higher adverse event in the histotype-tailored chemotherapy group (n=114) was neutropenia (30 [26%]). No treatment-related deaths were reported in both groups. In agreement with the Independent Data Monitoring Committee, the study was closed to patient entry after the third futility analysis. INTERPRETATION: In a population of patients with high-risk soft-tissue sarcoma, we did not show any benefit of a neoadjuvant histotype-tailored chemotherapy regimen over the standard chemotherapy regimen. The benefit seen with the standard chemotherapy regimen suggests that this benefit might be the added value of neoadjuvant chemotherapy itself in patients with high-risk soft-tissue sarcoma. FUNDING: European Union grant (Eurosarc FP7 278472).

Ten-Year Progression-Free and Overall Survival in Patients With Unresectable or Metastatic GI Stromal Tumors: Long-Term Analysis of the European Organisation for Research and Treatment of Cancer, Italian Sarcoma Group, and Australasian Gastrointestinal Trials Group Intergroup Phase III Randomized Trial on Imatinib at Two Dose Levels.

Purpose To report on the long-term results of a randomized trial comparing a standard dose (400 mg/d) versus a higher dose (800 mg/d) of imatinib in patients with metastatic or locally advanced GI stromal tumors (GISTs). Patients and Methods Eligible patients with advanced CD117-positive GIST from 56 institutions in 13 countries were randomly assigned to receive either imatinib 400 mg or 800 mg daily. Patients on the 400-mg arm were allowed to cross over to 800 mg upon progression. Results Between February 2001 and February 2002, 946 patients were accrued. Median age was 60 years (range, 18 to 91 years). Median follow-up time was 10.9 years. Median progression-free survival times were 1.7 and 2.0 years in the 400- and 800-mg arms, respectively (hazard ratio, 0.91; P = .18), and median overall survival time was 3.9 years in both treatment arms. The estimated 10-year progression-free survival rates were 9.5% and 9.2% for the 400- and 800-mg arms, respectively, and the estimated 10-year overall survival rates were 19.4% and 21.5%, respectively. At multivariable analysis, age (< 60 years), performance status (0 v ≥ 1), size of the largest lesion (smaller), and KIT mutation (exon 11) were significant prognostic factors for the probability of surviving beyond 10 years. Conclusion This trial was carried out on a worldwide intergroup basis, at the beginning of the learning curve of the use of imatinib, in a large population of patients with advanced GIST. With a long follow-up, 6% of patients are long-term progression free and 13% are survivors. Among clinical prognostic factors, only performance status, KIT mutation, and size of largest lesion predicted long-term outcome, likely pointing to a lower burden of disease. Genomic and/or immune profiling could help understand long-term survivorship. Addressing secondary resistance remains a therapeutic challenge.

Randomized Phase II Study of Trabectedin and Doxorubicin Compared With Doxorubicin Alone as First-Line Treatment in Patients With Advanced Soft Tissue Sarcomas: A Spanish Group for Research on Sarcoma Study.

PURPOSE: Doxorubicin and trabectedin are considered active drugs in soft tissue sarcoma (STS). The combination of both drugs was hypothesized to be advantageous and safe on the basis of preclinical evidence and a previous phase I trial, respectively. The aim of this study was to compare the clinical outcome of trabectedin plus doxorubicin with doxorubicin as first-line treatment of advanced STS patients. PATIENTS AND METHODS: In this open-label randomized phase II trial, the main end point was progression-free survival (PFS). Trabectedin 1.1 mg/m(2) in a 3-hour infusion plus doxorubicin 60 mg/m(2) as the experimental arm and doxorubicin 75 mg/m(2) as the control arm were administered for up to six cycles. Translational research was planned to correlate the expression of apoptotic and DNA repair genes with clinical outcome. RESULTS: In 115 randomly assigned patients, the median PFS was 5.5 months in the control arm and 5.7 months in the experimental arm (hazard ratio, 1.16; 95% CI, 0.79 to 1.71; P = .45) in the intent-to-treat analysis. The trial was stopped for futility after the interim analysis, because the results in the experimental arm showed the risk reduction for the main end point to be < 9.64%. The proportion of patients with grade 3 or 4 thrombocytopenia, asthenia, and liver toxicity was significantly higher in the experimental arm. FAS and p53 were shown to be prognostic factors for PFS (7.0 months if FAS+ and p53-; 3.4 months if FAS+/p53+ or FAS-/p53-; and 0.7 months if FAS- and p53+; P < .001) and for overall survival. CONCLUSION: Trabectedin plus doxorubicin did not show superiority over doxorubicin alone as first-line treatment of advanced STS. The prognostic role of apoptotic key genes, FAS and p53, was shown to be robust enough to continue this research line.

Complete longitudinal analyses of the randomized, placebo-controlled, phase III trial of sunitinib in patients with gastrointestinal stromal tumor following imatinib failure.

PURPOSE: To analyze final long-term survival and clinical outcomes from the randomized phase III study of sunitinib in gastrointestinal stromal tumor patients after imatinib failure; to assess correlative angiogenesis biomarkers with patient outcomes. EXPERIMENTAL DESIGN: Blinded sunitinib or placebo was given daily on a 4-week-on/2-week-off treatment schedule. Placebo-assigned patients could cross over to sunitinib at disease progression/study unblinding. Overall survival (OS) was analyzed using conventional statistical methods and the rank-preserving structural failure time (RPSFT) method to explore cross-over impact. Circulating levels of angiogenesis biomarkers were analyzed. RESULTS: In total, 243 patients were randomized to receive sunitinib and 118 to placebo, 103 of whom crossed over to open-label sunitinib. Conventional statistical analysis showed that OS converged in the sunitinib and placebo arms (median 72.7 vs. 64.9 weeks; HR, 0.876; P = 0.306) as expected, given the cross-over design. RPSFT analysis estimated median OS for placebo of 39.0 weeks (HR, 0.505, 95% CI, 0.262-1.134; P = 0.306). No new safety concerns emerged with extended sunitinib treatment. No consistent associations were found between the pharmacodynamics of angiogenesis-related plasma proteins during sunitinib treatment and clinical outcome. CONCLUSIONS: The cross-over design provided evidence of sunitinib clinical benefit based on prolonged time to tumor progression during the double-blind phase of this trial. As expected, following cross-over, there was no statistical difference in OS. RPSFT analysis modeled the absence of cross-over, estimating a substantial sunitinib OS benefit relative to placebo. Long-term sunitinib treatment was tolerated without new adverse events.

[Soft tissue sarcomas: clinical practice guidelines]. / Guía de práctica clínica en los sarcomas de partes blandas.

Soft tissue sarcomas (STS) constitute a rare heterogeneous group of tumours that include a wide variety of histological subtypes, which require a multidisciplinary and, frequently specialized and complex management. Despite advances in our understanding of the pathophysiology of the disease, there are no consensus multidisciplinary recommendations about its diagnosis and treatment in our country. The objective of these guidelines is to provide practical therapeutic recommendations that may contribute to improve the therapeutic results of this disease in our environment. With this purpose, the Spanish Group for Research in Sarcomas (GEIS) held a meeting with a multidisciplinary group of experts for the study and management of sarcomas. The results of this meeting are compiled in this document, in which recommendations on diagnosis, treatment and monitoring of soft tissue sarcomas are included. In summary, these guidelines aim to facilitate the identification and management of STS for clinical practice in Spain.