Retrospective inter- and intra-patient evaluation of trabectedin after best supportive care for patients with advanced translocation-related sarcoma after failure of standard chemotherapy

Mesenchymal Chondrosarcoma from Diagnosis to Clinical Trials

Mesenchymal chondrosarcoma (MCS) is a rare subtype of chondrosarcoma with a poor prognosis. Although these tumors are sensitive to radiotherapy/chemotherapy, the standard treatment for localized MCS is only surgical resection, and there are no established treatment guidelines for patients with advanced and metastatic MCS. Due to the low incidence of MCS, the pathology of these tumors is still unknown, and other therapeutic options are lacking. Some studies show the potential role of the PDGF/PPI3K/AKT, PKC/RAF/MEK/ERK, and pRB pathways, and BCL2 overexpression in the pathogenesis of MCS. These findings provide an opportunity to use protein kinases and BCL2 inhibitors as potential therapy in MCS. In this review, we summarize the current knowledge about MCS diagnosis and treatment options. We show the immunological and molecular biomarkers used in the diagnosis of MCS. In addition, we discuss the known prognostic and predictive factors in MCS. Finally, we present the novel trends, including targeted therapies and ongoing clinical trials using protein kinase inhibitors and the death receptor 5 (DR5) agonist, which may be the focus of future MCS treatment studies.

Transcription regulators and ultra-rare and other rare translocation-related sarcomas treated with trabectedin: A proof of principle from a post-hoc analysis

Background

Among sarcomas, which are rare cancers with an incidence of <6 per 100.000/year cases, ultra-rare sarcomas have an incidence of approximately ≤1/1,000,000/year cases and altogether account for ~20% of all soft tissue sarcomas (STS) and bone sarcomas. The Italian Sarcoma Group has recently performed a non-interventional, retrospective TrObs study with data from 512 anthracycline-pretreated patients with advanced multiple STS histologies and treated with trabectedin (Palmerini, Cancers 2021; ClinicalTrials.gov Identifier: NCT02793050).

Methods

A post-hoc analysis of case series to evaluate the efficacy and safety of trabectedin on patients with ultra-rare and other rare translocation-related sarcomas included in TrObs study was performed. Main outcomes comprised investigator-assessed overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS) and safety.

Results

Thirty-six patients (18 women) with ultra-rare and other rare sarcoma and a median age of 53.0 years (range: 22-81) were included. Most patients had solitary fibrous tumor (SFT; n=11) followed by epithelioid sarcoma (n=5), malignant peripheral nerve sheath tumor (MPNST; n=4), extraskeletal myxoid chondrosarcoma (EMC; n=3), desmoplastic small round cell tumor (DSRCT; n=3), and alveolar soft part sarcoma (ASPS), rhabdomyosarcoma and clear cell sarcoma (n=2 each). Thirty-five patients had metastatic disease and 23 patients received trabectedin as a second-line treatment. Among 35 patients evaluable for response, two patients with SFT and ASPS had a partial response and one patient with DSRCT obtained a complete response, reaching an ORR of 8.6% (95% CI: 2.8-23.4%). Among patients with an ORR, 6-months PFS was 100% in patients with ASPS, 45.7% in patients with SFT and 33.3% in those with DSRCT. Two patients with epithelioid sarcoma and myoepithelioma had disease stabilization lasting >24 months. Nine patients had at least one grade 3/4 adverse event, mostly being bone marrow toxicity (n=6).

Conclusions

Trabectedin has some anti-tumor activity in some ultra-rare and other rare sarcomas, particularly translocation-related sarcomas, with the well-known manageable safety profile.

Meta-analysis of pazopanib and trabectedin effectiveness in previously treated metastatic synovial sarcoma (second-line setting and beyond)

Background: This study examined the efficacy/effectiveness of pazopanib and trabectedin in previously treated metastatic synovial sarcoma (mSS). Materials & methods: A literature search identified studies (2002-2019) reporting outcomes of pazopanib and trabectedin in previously treated mSS, including median overall survival (mOS) and overall response rate (ORR). A meta-analysis was conducted and sensitivity analyses examined outcomes by agent (pazopanib/trabectedin), study type (clinical trial [CT] or real-world [RW]) and sample size. Results: Sixteen studies were included (pazopanib: n = 7; trabectedin: n = 9). Pooled mOS was 10.4 months and was consistent across agents and in RW and CT (pazopanib: 10.3; trabectedin: 10.4; CT: 10.8; RW: 9.9). ORR results were more variable (pooled ORR: 14.7%). ORR was consistently higher for RW (17.7%) than for CT (9.5%) and for pazopanib (18.9%) compared with trabectedin (12.3%). Conclusion: Poor outcomes across agents and settings highlight a need for novel treatments with improved efficacy. This study serves as a benchmark for efficacy estimates in this rare disease.

Patterns of care and outcomes of 417 patients with METAstatic SYNovial sarcoma (METASYN): real-life data from the French Sarcoma Group (FSG)

Background

Synovial sarcoma (SS) occurs in both adult and pediatric patients. The primary aim of this study is to describe the outcomes, prognostic factors, and treatment of patients with metastatic SS within a nationwide cohort.

Patients and methods

All pediatric and adult patients with metastatic SS are registered in the French Sarcoma Group database. Data were collected from the national database https://conticabase.sarcomabcb.org/ up to March 2020. Descriptive and comparative analyses were conducted using SAS 9.4 and Stata Special Edition 16.1 software.

Results

Between January 1981 and December 2019, 417 patients with metastatic SS from 17 French sarcoma centers were included, including 64 (15.3%) under the age of 26 years. Median age was 42.5 years (range 9-87 years). The metastases were synchronous (cohort 1) or metachronous (cohort 2) in 18.9% (N = 79) and 81.1% (N = 338) patients, respectively. Median overall survival (OS) from the date of metastasis was 22.3 months (95% confidence interval 19.7-24.1 months). First-line chemotherapy without ifosfamide and/or doxorubicin was unfavorable for progression-free survival and OS (P < 0.001). Concerning cohort 1, young age, surgery of the primary tumor, and single metastatic site were independent favorable prognostic factors for OS. In cohort 2, surgery within an expert French Sarcoma Group center, absence of chemotherapy in the perioperative setting, the lungs as a single metastatic site, time to first metastasis >12 months, local therapy, and ifosfamide in the first metastatic line were independent favorable prognostic factors.

Conclusions

The outcome of patients with metastatic SS is influenced by local treatment, management in reference centers, and cytotoxic treatments given in the perioperative and metastatic setting.

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METASYN is the largest retrospective study on metastatic adult and pediatric SS.

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This study confirms that surgery remains the mainstay for improving OS in reference centers.

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METASYN emphasizes the importance of focal treatment of metastases for OS.

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This study offers real-life results in a metastatic setting and is a useful support for developing new strategies.

Long lasting response with trabectedin monotherapy in relapsed metastatic mesenchymal chondrosarcoma

Background

Mesenchymal chondrosarcoma is an exceedingly rare malignancy, accounting for around 5% of all patients with chondrosarcoma. It is a translocation-related sarcoma that tends to have both local and distant recurrences. Surgery is the mainstay of treatment in localised cases however treatment of advanced cases remains a challenge. The rarity of the disease precludes dedicated clinical trials and hence guidelines for its management are not well defined. The dearth in literature makes it pertinent that the cases treated with newer therapies must be reported to contribute to existing knowledge.

Case presentation

We hereby report a case of a 39-year old male without any comorbidity presenting with pelvic pain and was diagnosed as mesenchymal chondrosarcoma of the pelvis. He underwent an initial curative resection followed by a disease-free interval of 7 months. Subsequently, he was treated with pulmonary metastatectomy and local debulking surgery at time of initial relapse. He was then exposed to multiple lines of palliative chemotherapy, which limited our treatment options upon subsequent disease progression. Based on recent data, the patient was given trabectedin monotherapy as fourth line chemotherapy. He tolerated the therapy well and attained a progression-free survival of 12 months, which is an impactful figure in relapsed setting in this patient population.

Conclusion

This report aims to present a comprehensive review into available and newer treatment choices for mesenchymal chondrosarcoma, and to highlight trabectedin monotherapy as a possible therapeutic option for mesenchymal chondrosarcoma in the relapsed setting.

Time lapse analysis of tumor response in patients with soft tissue sarcoma treated with trabectedin: A pooled analysis of two phase II clinical trials

The time course of the response to each drug is important to avoid inappropriate termination of treatment by misjudging tumor progression; however, little is known about soft tissue sarcoma (STS) regarding this matter. This study aimed to perform a time-lapse analysis of tumor response in patients with STS treated with trabectedin from 2 phase II clinical trials. We examined 66 patients with translocation-related sarcoma registered in 2 Japanese phase II clinical trials. All patients previously received standard therapy before the administration of trabectedin at 1.2 mg/m² every 3 weeks. Imaging evaluation was performed according to the study protocol. The sum of the maximum diameters of the target lesions was calculated and analyzed over time. Among the 66 patients, 9 (13.6%) showed partial response (PR) to trabectedin. Histological diagnoses of these 9 responders comprised 6 myxoid liposarcoma, 2 synovial sarcoma, and a mesenchymal chondrosarcoma. The median period from treatment initiation to the first PR was 123 (range, 34-328) days. The pattern of tumor response to trabectedin showed an increasing tendency in size in the initial stage, usually followed by a size decrease with repeated administration. STS response to trabectedin was characterized as delayed and potentially persistent. Clinicians treating STS with trabectedin should know the features of the response pattern to avoid interrupting the treatment before maximal efficacy is achieved.

A phase II multi-strata study of lurbinectedin as a single agent or in combination with conventional chemotherapy in metastatic and/or unresectable sarcomas

Chemotherapy objective response rates (ORRs) in metastatic soft tissue sarcoma (STS) are typically 20-40% with median progression-free survival (PFS) less than 6 months. Lurbinectedin is a new anticancer agent under investigation. The primary objective of this three-arm, phase II study was to determine the disease control rate (DCR = ORR + stable disease [SD]) at 24 weeks of lurbinectedin alone or with chemotherapy in STS. Eligible patients included adults with ≤2 prior cytotoxic therapies. Study cohorts were: stratum A (StrA; anthracycline-naive), lurbinectedin/doxorubicin; stratum B (StrB; prior anthracycline), lurbinectedin/gemcitabine; stratum C (StrC; prior anthracycline/gemcitabine) lurbinectedin monotherapy. Each stratum was analysed separately by Simon two-stage design. Forty-two patients were accrued (StrA = 20, StrB = 10, StrC = 12) including leiomyosarcoma [LMS] (n = 20), synovial sarcoma [SS](n = 4), malignant peripheral nerve sheath tumour (n = 3) and other STS histologies (n = 15). For StrA there were seven partial responses (PR) plus one stable disease (SD) at 24 weeks. For StrB, two patients met the 24-week DCR including one PR (leiomyosarcoma) and one SD (desmoplastic small round cell tumour [DSRCT]). StrB did not continue to the second stage. In StrC, no patients met the primary end-point. Median progression-free survival (PFS) was: StrA = 4.2 months (90% CI 1.4-7.8), StrB = 1.7 months (90% confidence interval (CI) 1.0-7.4), and StrC = 1.3 months (90% CI 1.1-3.0). Lurbinectedin as a single agent or with chemotherapy was well tolerated with haematologic adverse events (AE's) as the most common toxicity. There were no treatment-related deaths. The combination of lurbinectedin/doxorubicin reached the DCR end-point with seven PR and one patient with SD (ORR 35.0%, 24-week DCR 40.0%). Evidence of drug benefit was seen in leiomyosarcoma, dedifferentiated liposarcoma (DDLS), myxoid liposarcoma (MLS), synovial sarcoma (SS), and desmoplastic small round cell tumour (DSRCT). TRIAL REGISTRATION: clinicaltrials.gov; NCT02448537.

Advances in sarcoma diagnostics and treatment

The heterogeneity of sarcomas with regard to molecular genesis, histology, clinical characteristics, and response to treatment makes management of these rare yet diverse neoplasms particularly challenging. This review encompasses recent developments in sarcoma diagnostics and treatment, including cytotoxic, targeted, epigenetic, and immune therapy agents. In the past year, groups internationally explored the impact of adding mandatory molecular testing to histological diagnosis, reporting some changes in diagnosis and/or management; however, the impact on outcomes could not be adequately assessed. Transcriptome sequencing techniques have brought forward new diagnostic tools for identifying fusions and/or characterizing unclassified entities. Next-generation sequencing and advanced molecular techniques were also applied to identify potential targets for directed and epigenetic therapy, where preclinical studies reported results for agents active within the receptor tyrosine kinase, mTOR, Notch, Wnt, Hedgehog, Hsp90, and MDM2 signaling networks. At the level of clinical practice, modest developments were seen for some sarcoma subtypes in conventional chemotherapy and in therapies targeting the pathways activated by various receptor tyrosine kinases. In the burgeoning field of immune therapy, sarcoma work is in its infancy; however, elaborate protocols for immune stimulation are being explored, and checkpoint blockade agents advance from preclinical models to clinical studies.

Efficacy of Trabectedin in Patients with Advanced Translocation-Related Sarcomas: Pooled Analysis of Two Phase II Studies

This analysis updates the results of two phase II studies of translocation‐related sarcomas to evaluate the efficacy of trabectedin against histological subtype and analyze overall survival.

Background.

Trabectedin is reported as effective, especially against translocation‐related sarcomas (TRSs) after failure of or intolerance to standard chemotherapy. We conducted two phase II studies of TRS, confirming high efficacy of 1.2 mg/m² trabectedin. The updated data of 66 patients in these studies was integrated to evaluate the efficacy of trabectedin against each histological subtype, and analyze final overall survival (OS).

Methods.

Trabectedin was administered on day one of a 21‐day cycle. Efficacy was assessed using progression‐free survival (PFS), OS, and best overall response. An analysis of OS and PFS was performed for subgroups divided by baseline lymphocyte count (<1,000/μL, ≥1,000/μL) or number of previous chemotherapy regimens (0, 1, 2, ≥3 regimens), and a Weibull parametric model was used to estimate the numerical relationship between lymphocyte count and PFS and OS.

Results.

Median PFS and OS in overall patients were 5.6 (95% confidence interval [CI]: 4.1–7.3) and 17.5 months (95% CI: 12.6–23.6), respectively. PFS in the myxoid and round‐cell liposarcoma (MRCL) group (7.4 months [95% CI: 5.6–11.1]) was longer than in the other subtypes. The response rate was also highest in the MRCL group. Median OS was longer in patients with baseline lymphocyte counts ≥1,000/μL than in those with counts of <1,000/μL, but median PFS was not different between the two subgroups.

Conclusion.

Our updated and pooled data showed that trabectedin exerted prolonged disease control and antitumor effects in patients with advanced TRS, especially in MRCL. We consider that the subgroup analyses also provide important information for trabectedin treatment in patients with TRS.

Implications for Practice.

The progression‐free survival (PFS) for the integrated data of 66 patients with translocation‐related sarcomas (TRSs) in two phase II studies of trabectedin 1.2 mg/m² was 5.6 months (95% confidence interval: 4.1–7.3). PFS and response rate in myxoid/round‐cell liposarcoma was longer than that of other subtypes. The overall survival (OS) in all TRS subtypes was similar to previous data of TRS patients. In subgroup analysis, the patients with baseline lymphocyte count ≥1,000/μL exhibited better OS, although PFS was not different by baseline lymphocyte count. Our data are considered important information for trabectedin treatment in TRS patients.

Autologous hematopoietic stem cell transplantation following high-dose chemotherapy for nonrhabdomyosarcoma soft tissue sarcomas

BACKGROUND

Soft tissue sarcomas (STS) are a highly heterogeneous group of rare malignant solid tumors. Nonrhabdomyosarcoma soft tissue sarcomas (NRSTS) comprise all STS except rhabdomyosarcoma. In people with advanced local or metastatic disease, autologous hematopoietic stem cell transplantation (HSCT) applied after high-dose chemotherapy (HDCT) is a planned rescue therapy for HDCT-related severe hematologic toxicity. The rationale for this update is to determine whether any randomized controlled trials (RCTs) have been conducted and to clarify whether HDCT followed by autologous HSCT has a survival advantage.

OBJECTIVES

To assess the efficacy and safety of high-dose chemotherapy (HDCT) followed by autologous hematopoietic stem cell transplantation (HSCT) for all stages of nonrhabdomyosarcoma soft tissue sarcomas (NRSTS) in children and adults.

SEARCH METHODS

For this update, we revised the search strategy to improve the precision and reduce the number of irrelevant hits. We searched the following electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 8), PubMed from 2012 to 6 September 2016, and Embase from 2012 to 26 September 2016. We searched online trial registries and congress proceedings from 2012 to 26 September 2016.

SELECTION CRITERIA

Terms representing STS and autologous HSCT were required in the title or abstract. We restricted the study design to RCTs. We included studies if at least 80% of participants had a diagnosis listed in any version of the World Health Organization (WHO) classification and classified as malignant. The search included children and adults with no age limits.

DATA COLLECTION AND ANALYSIS

We used standard methodologic procedures expected by Cochrane. The primary outcomes were overall survival and treatment-related mortality.

MAIN RESULTS

We identified 1549 records; 85 items from electronic databases, 45 from study registries, and 1419 from congress proceedings. The revised search strategy did not identify any additional RCTs. In the previous version of the review, we identified one RCT comparing HDCT followed by autologous HSCT versus standard-dose chemotherapy (SDCT). The trial randomized 87 participants who were considerably heterogeneous with respect to 19 different tumor entities. The data from 83 participants were available for analysis.In the single included trial, overall survival at three years was 32.7% in the HDCT arm versus 49.4% in the SDCT arm and there was no difference between the treatment groups (hazard ratio (HR) 1.26, 95% confidence interval (CI) 0.70 to 2.29, P = 0.44; 1 study, 83 participants; high quality evidence). In a subgroup of participants who had a complete response before HDCT, overall survival was higher in both treatment groups and overall survival at three years was 42.8% in the HDCT arm versus 83.9% in the SDCT arm and favored the SDCT group (HR 2.92, 95% CI 1.1 to 7.6, P = 0.028; 1 study, 39 participants).In the single included trial, the authors reported one treatment-related leukemia death two years after HDCT. They also evaluated severe adverse events WHO grade 3 to 4 in 22 participants in the HDCT arm and in 51 participants in the SDCT arm. The authors reported 11 events concerning digestive-, infection-, pain-, or asthenia-related toxicity in the HDCT arm and one event in the SDCT arm (moderate quality evidence). The development of secondary neoplasia was not addressed. We judged the study to have an overall unclear risk of bias as three of seven items had unclear and four items had low risk of bias. For GRADE, we judged three items as high quality and three items were not reported.

AUTHORS' CONCLUSIONS

The limited data of a single RCT with an unclear risk of bias and moderate to high quality evidence showed no survival advantage for HDCT. If this treatment is offered it should only be given after careful consideration on an individual person basis and possibly only as part of a well-designed RCT.

Trabectedin for the treatment of soft tissue sarcomas

INTRODUCTION

Trabectedin, a marine-derived DNA-binding antineoplastic agent, has been registered by the EMA and recently also by the FDA for the treatment of patients with advanced soft-tissue sarcoma (STS), a rare and heterogeneous disease.

AREAS COVERED

The antitumor activity of trabectedin is related both to direct effects on cancer cells, such as growth inhibition, cell death and differentiation, and indirect effects related to its anti-inflammatory and anti-angiogenic properties. Furthermore, trabectedin is the first compound that targets an oncogenic transcription factor with high selectivity in mixoid liposarcomas. This peculiar mechanism of action is the basis of its clinical development. The clinical pharmacology of trabectedin, the subsequent phase I, II and III trials are summarized and put into perspectives in this review.

EXPERT OPINION

Trabectedin is a relevant pleiotropic antitumoral agent within the complex scenario of the management of STS. It can be used in advanced STS, either after failure of anthracyclines and ifosfamide or in patients unfit for these drugs, especially when reaching a high-tumor control and a long-term benefit is a priority. Toxicity profile is acceptable and manageable with no reported cumulative toxicities. Therefore, trabectedin has become one relevant therapeutic option in metastatic STS, especially in selected histologies.