Efficacy and Safety of Trabectedin or Dacarbazine for Metastatic Liposarcoma or Leiomyosarcoma After Failure of Conventional Chemotherapy: Results of a Phase III Randomized Multicenter Clinical Trial

Major clinical research advances in gynecologic cancer in 2015

In 2015, fourteen topics were selected as major research advances in gynecologic oncology. For ovarian cancer, high-level evidence for annual screening with multimodal strategy which could reduce ovarian cancer deaths was reported. The best preventive strategies with current status of evidence level were also summarized. Final report of chemotherapy or upfront surgery (CHORUS) trial of neoadjuvant chemotherapy in advanced stage ovarian cancer and individualized therapy based on gene characteristics followed. There was no sign of abating in great interest in immunotherapy as well as targeted therapies in various gynecologic cancers. The fifth Ovarian Cancer Consensus Conference which was held in November 7-9 in Tokyo was briefly introduced. For cervical cancer, update of human papillomavirus vaccines regarding two-dose regimen, 9-valent vaccine, and therapeutic vaccine was reviewed. For corpus cancer, the safety concern of power morcellation in presumed fibroids was explored again with regard to age and prevalence of corpus malignancy. Hormone therapy and endometrial cancer risk, trabectedin as an option for leiomyosarcoma, endometrial cancer and Lynch syndrome, and the radiation therapy guidelines were also discussed. In addition, adjuvant therapy in vulvar cancer and the updated of targeted therapy in gynecologic cancer were addressed. For breast cancer, palbociclib in hormone-receptor-positive advanced disease, oncotype DX Recurrence Score in low-risk patients, regional nodal irradiation to internal mammary, supraclavicular, and axillary lymph nodes, and cavity shave margins were summarized as the last topics covered in this review.

Assessment of Imaging Modalities and Response Metrics in Ewing Sarcoma: Correlation With Survival

PURPOSE

Despite the rapidly increasing use of [¹⁸F]fluorodeoxyglucose (FDG) -positron emission tomography (PET), the comparison of anatomic and functional imaging in the assessment of clinical outcomes has been lacking. In addition, there has not been a rigorous evaluation of how common radiologic criteria or the location of the radiology reader (local v central) compare in the ability to predict benefit. In this study, we aimed to compare the effectiveness of various radiologic response assessments for the prediction of overall survival (OS) within the same data set of patients with sarcoma.

METHODS

We analyzed assessments made during a clinical trial of a novel IGF1R antibody in Ewing sarcoma: PET Response Criteria in Solid Tumors (PERCIST) for functional imaging and WHO criteria (performed locally and centrally), RECIST, and volumetric analysis for anatomic imaging. We compared the effectiveness of the various criteria for the prediction of progression and survival.

RESULTS

For volume analysis, progression-defined as cumulative lesion volume increase of 100% at 6 weeks-was the optimal cutoff for decreased OS (P < .001). Assessment of the day-9 FDG-PET scan was associated with reduced OS in progressors compared with nonprogressors (P = .001) and with improved OS in responders compared with nonresponders. Significant variations in response (18% to 44%) and progression (9% to 50%) were observed between the different criteria. The comparison of central and local interpretation of anatomic imaging produced similar outcomes. PET was superior to anatomic imaging in identification of a response. Volume analysis identified the most responders among the anatomic imaging criteria.

CONCLUSION

An early signal with FDG-PET on day 9 and volume analysis were the best predictors of benefit. Validation of the volumetric analysis is required.

Current classification, treatment options, and new perspectives in the management of adipocytic sarcomas

Sarcomas are a heterogeneous group of mesenchymal tumors arising from soft tissue or bone, with an uncertain etiology and difficult classification. Soft tissue sarcomas (STSs) account for around 1% of all adult cancers. Till date, more than 50 histologic subtypes have been identified. Adipocyte sarcoma or liposarcoma (LPS) is one of the most common STS subtypes, accounting for 15% of all sarcomas, with an incidence of 24% of all extremity STSs and 45% of all retroperitoneal STSs. The new World Health Organization classification system has divided LPS into four different subgroups: atypical lipomatous tumor/well-differentiated LPS, dedifferentiated LPS, myxoid LPS, and pleomorphic LPS. These lesions can develop at any location and exhibit different aggressive potentials reflecting their morphologic diversity and clinical behavior. Patients affected by LPS should be managed in specialized multidisciplinary cancer centers. Whereas surgical resection is the mainstay of treatment for localized disease, the benefits of adjuvant and neoadjuvant chemotherapy are still unclear. Systemic treatment, particularly chemotherapy, is still limited in metastatic disease. Despite the efforts toward a better understanding of the biology of LPS, the outcome of advanced and metastatic patients remains poor. The advent of targeted therapies may lead to an improvement of treatment options and clinical outcomes. A larger patient enrollment into translational and clinical studies will help increase the knowledge of the biological behavior of LPSs, test new drugs, and introduce new methodological studies, that is, on treatment response.

Association of the germline BRCA2 missense variation Glu2663Lys with high sensitivity to trabectedin-based treatment in soft tissue sarcoma

We report an interesting clinical case of a patient carrying a specific BRCA2 germline variant affected by bone and hepatic metastases from a high grade uterine stromal sarcoma who obtained a complete metabolic response after only 3 cycles of trabectedin treatment (1.5 mg/m² given intravenously over 24 hours every 21 days). Molecular investigations linked this outstanding positive pharmacological response with the loss of heterozygosity (LOH) of the mutated BRCA2 gene. These data support the hypothesis that the response to trabectedin may be positively conditioned by the different DNA repair defects present in the neoplasm and that BRCAness tumor genotype is important in determining the efficacy of trabectedin-based chemotherapy.

Efficacy and safety of eribulin mesylate in advanced soft tissue sarcomas

Despite recent advances in the field, treatment options for metastatic soft tissue sarcoma patients are limited. Eribulin, an antimitotic derived from the natural marine sponge product halichondrin B, is currently approved for the treatment of metastatic breast cancer. Following the promising activity of eribulin in sarcoma in a Phase II trial, the drug was recently compared to dacarbazine in pretreated advanced leiomyosarcoma (LMS) and liposarcoma (LPS) patients in a Phase III trial. Eribulin was associated with a significant 2-month improvement in median overall survival compared to dacarbazine (13.5 vs. 11.5 months, heart rate: 0.768) despite no documented significant difference in progression-free survival. In a subgroup analysis, the survival advantage associated with eribulin was evident in the LPS subgroup but not in the LMS subgroup. Following these encouraging results, the Food and Drug Administration has approved eribulin for the treatment of advanced LPS for patients who received prior anthracycline chemotherapy. In this short review, we will evaluate the evidence for eribulin in soft tissue sarcoma, highlight its mechanisms of action, and summarize the results of the major preclinical and clinical studies with a particular focus on the results of the Phase III trial.

Efficacy of trabectedin for the treatment of liposarcoma

INTRODUCTION

Trabectedin (ET-743) is a synthetic marine derived alkylating agent, extracted originally from a Caribbean Sea sponge. It is approved for the treatment of Soft Tissue sarcomas (STS) in Europe and recently by the FDA for liposarcomas and leiomyosarcomas.

AREAS COVERED

Trabectedin has multiple mechanisms of action, including one targeting the FUS-CHOP oncogene in Myxoid/Round cell Liposarcomas. Numerous Phase I, II and III clinical trials have been conducted with Trabectedin. It has been studied as monotherapy or in combination with other chemotherapeutic agents. The recommended dose based on clinical trials is 1.5 milligrams/m(2) continuous infusion over 24 hours once every 3 weeks for STS with evidence of disease control in multiple clinical trials at this dose. The most common Grade 3/4 toxicities include neutropenia and transient noncumulative elevations of ALT and AST. Steroid pretreatment has shown efficacy in reducing liver and bone marrow toxicity. In phase III testing comparing trabectedin to dacarbazine, trabectedin was associated with a significantly improved progression free survival rate in patients with advanced lipo- and leiomyosarcomas.

EXPERT OPINION

Trabectedin is an important new addition to the limited treatment options currently available for STS, especially for patients with liposarcoma that have progressed on standard chemotherapeutic regimens.

Eribulin in the management of inoperable soft-tissue sarcoma: patient selection and survival

Patients diagnosed with metastatic soft-tissue sarcoma (STS) have a poor prognosis. Additionally, after failure of first-line therapy, there are relatively few treatment options from which to choose. The novel tubulin-binding drug, eribulin, with a unique mechanism of action from taxanes or vinca alkaloids, has shown clinical activity in several different types of cancers. Eribulin has been approved by the US Food and Drug Administration (FDA) for patients with metastatic breast cancer previously treated with an anthracycline or a taxane and has recently been FDA approved for patients with unresectable or metastatic liposarcoma who have failed a previous anthracycline regimen. Here, we review current standard treatments of STS, a background of eribulin, the studies that have propelled eribulin to FDA approval for liposarcoma, and future directions of the drug. The benefits of eribulin in STS are discussed in detail, especially with regard to the recent pivotal Phase III study comparing eribulin to dacarbazine for leiomyosarcoma and adipocytic sarcoma.

Advanced soft-tissue sarcoma and treatment options: critical appraisal of trabectedin

Soft-tissue sarcomas (STS) are a heterogeneous group of rare solid tumors of mesenchymal origin. This paper reviews the current status of systemic treatment in advanced and metastatic soft tissue sarcomas, with an emphasis on trabectedin. Trabectedin is a unique type of chemotherapeutic agent with multiple potential mechanisms of action. We discuss the putative mechanisms, as well as the toxicity and administration schedules of trabectedin, followed by its efficacy in first-line systemic therapy and beyond first-line systemic therapy.

Phase II study of MLN8237 (Alisertib) in advanced/metastatic sarcoma

BACKGROUND

Aurora kinase A (AURKA) is commonly overexpressed in sarcoma. The inhibition of AURKA by shRNA or by a specific AURKA inhibitor blocks in vitro proliferation of multiple sarcoma subtypes. MLN8237 (alisertib) is a novel oral adenosine triphosphate-competitive AURKA inhibitor.

PATIENTS AND METHODS

This Cancer Therapy Evaluation Program-sponsored phase II study of alisertib was conducted through the Alliance for Clinical Trials in Oncology (A091102). Patients were enrolled into histology-defined cohorts: (i) liposarcoma, (ii) leiomyosarcoma, (iii) undifferentiated sarcoma, (iv) malignant peripheral nerve sheath tumor, or (v) other. Treatment was alisertib 50 mg PO b.i.d. d1-d7 every 21 days. The primary end point was response rate; progression-free survival (PFS) was secondary. One response in the first 9 patients expanded enrollment in a cohort to 24 using a Simon two-stage design.

RESULTS

Seventy-two patients were enrolled at 24 sites [12 LPS, 10 LMS, 11 US, 10 malignant peripheral nerve sheath tumor (MPNST), 29 Other]. The median age was 55 years; 54% were male; 58%/38%/4% were ECOG PS 0/1/2. One PR expanded enrollment to the second stage in the other sarcoma cohort. The histology-specific cohorts ceased at the first stage. There were two confirmed PRs in the other cohort (both angiosarcoma) and one unconfirmed PR in dedifferentiated chondrosarcoma. Twelve-week PFS was 73% (LPS), 44% (LMS), 36% (US), 60% (MPNST), and 38% (Other). Grade 3-4 adverse events: oral mucositis (12%), anemia (14%), platelet count decreased (14%), leukopenia (22%), and neutropenia (42%).

CONCLUSIONS

Alisertib was well tolerated. Occasional responses, yet prolonged stable disease, were observed. Although failing to meet the primary RR end point, PFS was promising.

TRIAL REGISTRATION ID

NCT01653028.

Uterine sarcoma Part I-Uterine leiomyosarcoma: The Topic Advisory Group systematic review

Uterine sarcomas account for 3-7% of all uterine cancers. Because of their rarity, unknown etiology, and highly divergent genetic aberration, there is a lack of consensus on risk factors for occurrence and predictive poor outcomes as well as optimal therapeutic choices. Tumor types according to the World Health Organization classification include leiomyosarcoma, endometrial stroma sarcoma, and undifferentiated sarcoma. Staging is done using the 2014 Federation International Gynecology and Obstetrics and 2010 American Joint Committee on Cancer tumor, lymph node, and metastases systems. Tumor grade can be classified based on the French Federation of Cancer Centers Sarcoma Group system or the Broder's system that incorporates tumor differentiation, mitotic count, and tumor necrosis. This review is a series of articles discussing uterine sarcoma, and this is Part I, which focuses on one of the subtypes of uterine sarcomas-uterine leiomyosarcoma. The clinical characteristics, diagnosis, outcome, and recent advances are summarized in this article.

Liposarcoma: Multimodality Management and Future Targeted Therapies

There are 3 biologic groups of liposarcoma: well-differentiated and dedifferentiated liposarcoma, myxoid/round cell liposarcoma, and pleomorphic liposarcoma. In all 3 groups, complete surgical resection is central in treatment aimed at cure and is based on grade. Radiation can reduce risk of local recurrence in high-grade lesions or minimize surgical morbidity in the myxoid/round cell liposarcoma group. The groups differ in chemosensitivity, so adjuvant chemotherapy is selectively used in histologies with metastatic potential but not in the resistant subtype dedifferentiated liposarcoma. Improved understanding of the genetic aberrations that lead to liposarcoma initiation is allowing for the rapid development of targeted therapies for liposarcoma.

In Vivo Bioorthogonal Chemistry Enables Local Hydrogel and Systemic Pro-Drug To Treat Soft Tissue Sarcoma

The ability to activate drugs only at desired locations avoiding systemic immunosuppression and other dose limiting toxicities is highly desirable. Here we present a new approach, named local drug activation, that uses bioorthogonal chemistry to concentrate and activate systemic small molecules at a location of choice. This method is independent of endogenous cellular or environmental markers and only depends on the presence of a preimplanted biomaterial near a desired site (e.g., tumor). We demonstrate the clear therapeutic benefit with minimal side effects of this approach in mice over systemic therapy using a doxorubicin pro-drug against xenograft tumors of a type of soft tissue sarcoma (HT1080).

Phase IB Study of Selinexor, a First-in-Class Inhibitor of Nuclear Export, in Patients With Advanced Refractory Bone or Soft Tissue Sarcoma

PURPOSE

We evaluated the pharmacokinetics (PKs), pharmacodynamics, safety, and efficacy of selinexor, an oral selective inhibitor of nuclear export compound, in patients with advanced soft tissue or bone sarcoma with progressive disease.

PATIENTS AND METHODS

Fifty-four patients were treated with oral selinexor twice per week (on days 1 and 3) at one of three doses (30 mg/m(2), 50 mg/m(2), or flat dose of 60 mg) either continuously or on a schedule of 3 weeks on, 1 week off. PK analysis was performed under fasting and fed states (low v high fat content) and using various formulations of selinexor (tablet, capsule, or suspension). Tumor biopsies before and during treatment were evaluated for pharmacodynamic changes.

RESULTS

The most commonly reported drug-related adverse events (grade 1 or 2) were nausea, vomiting, anorexia, and fatigue, which were well managed with supportive care. Commonly reported grade 3 or 4 toxicities were fatigue, thrombocytopenia, anemia, lymphopenia, and leukopenia. Selinexor was significantly better tolerated when administered as a flat dose on an intermittent schedule. PK analysis of selinexor revealed a clinically insignificant increase (approximately 15% to 20%) in drug exposure when taken with food. Immunohistochemical analysis of paired tumor biopsies revealed increased nuclear accumulation of tumor suppressor proteins, decreased cell proliferation, increased apoptosis, and stromal deposition. Of the 52 patients evaluable for response, none experienced an objective response by RECIST (version 1.1); however, 17 (33%) showed durable (≥ 4 months) stable disease, including seven (47%) of 15 evaluable patients with dedifferentiated liposarcoma.

CONCLUSION

Selinexor was well tolerated at a 60-mg flat dose on a 3-weeks-on, 1-week-off schedule. There was no clinically meaningful impact of food on PKs. Preliminary evidence of anticancer activity in sarcoma was demonstrated.

A Systematic Literature Review of Adverse Events Associated with Systemic Treatments Used in Advanced Soft Tissue Sarcoma

This systematic literature review describes adverse events (AEs) among patients with soft tissue sarcoma (STS) who received second-line or later anticancer therapies. Searches were conducted in PubMed, EMBASE, and Cochrane Central Register of Controlled Trials for studies of adults with advanced or metastatic STS who received systemic anticancer therapy before enrollment in a randomized-controlled trial of pazopanib, another targeted cancer agent, or cytotoxic chemotherapy. Of 204 publications identified, seven articles representing six unique studies met inclusion criteria. Additional safety results for pazopanib were identified on ClinicalTrials.gov. Hematologic toxicities were common with all therapies evaluated (pazopanib, trabectedin, dacarbazine ± gemcitabine, gemcitabine ± docetaxel, cyclophosphamide, and ifosfamide). Studies differed in AE type, timing of assessment, and outcomes reported, although patient populations and AE assessment timing were relatively similar for pazopanib and trabectedin. AEs that were more common with trabectedin than pazopanib were anemia, neutropenia, nausea/vomiting, and elevations in aspartate aminotransferase and alanine aminotransferase. An AE that was more common with pazopanib than trabectedin was anorexia. Only the pazopanib study reported AE frequencies versus placebo. A planned meta-analysis was not feasible, as there was no common comparator. More well-designed studies that include common comparators are needed for comparison of safety effects among treatments for STS.

Chemotherapy for soft tissue sarcoma

Soft tissue sarcoma is a term used to describe a heterogeneous group of many rare tumors. Since the initial description of activity of doxorubicin, several additional agents have been brought to bear in the treatment of these diseases. Despite 2 recent drug approvals, doxorubicin and ifosfamide remain the most effective chemotherapy drugs available for the treatment of majority of these tumors. Optimal dosing and administration influence outcomes because of the steep dose-response curves associated with these agents. The debate endures regarding whether patients who have advanced disease should routinely receive single agents sequentially or in combination. Adjuvant therapy remains similarly controversial, although meta-analyses do support its use. Contemporary treatment of soft tissue sarcoma routinely incorporates additional lines of treatment that have become available over the last 15 years. Fixed-dose-rate gemcitabine with or without docetaxel is a standard second-line treatment. In keeping with the paradigm shift favoring subset-specific therapy, several recent approvals are linked with specific sarcoma subtypes. Eribulin has recently been approved on the basis of improved overall survival for patients with adipocytic sarcomas, and trabectedin is now approved in the United States for patients with leiomyosarcoma and liposarcoma. Within the spectrum of targeted therapies, pazopanib is approved for all nonadipocytic sarcomas, and imatinib is approved for dermatofibrosarcoma protuberans. Each of these drugs represents incremental rather than radical progress, although they constitute important and much needed treatment options for patients with these diseases. Cancer 2016;122:2952-2960. © 2016 American Cancer Society.

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.

Trabectedin for Soft Tissue Sarcoma: Current Status and Future Perspectives

Trabectedin (ET743, Yondelis^®, manufactured by Baxter Oncology GmbH, Halle/Westfalen, Germany, for Janssen Products, LP, Horsham, PA), derived from the marine ascidian, Ecteinascidia turbinata, is a natural alkaloid with multiple complex mechanisms of action. On 23 October 2015, 15 years after the results of the first Phase 1 clinical trial using trabectedin for chemotherapy-resistant solid malignancies was reported, and 8 years after its approval in Europe, the United States Food and Drug Administration (USFDA) finally approved trabectedin for the treatment of unresectable or metastatic liposarcoma or leiomyosarcoma that has failed a prior anthracycline-containing regimen. Approval was based on the results of a pivotal Phase 3 trial involving a 2:1 randomization of 518 patients (who were further stratified by soft tissue sarcoma subtype), in which a significant improvement in progression-free survival was reported in the trabectedin-treated group vs. the dacarbazine-treated group (p < 0.001). In this trial, the most common adverse reactions were nausea, fatigue, vomiting, constipation, anorexia, diarrhea, peripheral edema, dyspnea, and headache, while the most serious were neutropenic sepsis, rhabdomyolysis, cardiomyopathy, hepatotoxicity, and extravasation leading to tissue necrosis. The most common grade 3–4 adverse events were laboratory abnormalities of myelosuppression in both arms and transient transaminitis in the trabectedin arm. In a recent Phase 2 trial, trabectedin had a similar outcome as doxorubicin when given as a single agent in the first-line setting. Studies are also being conducted to expand the use of trabectedin not only as a first-line cancer drug, but also for a number of other clinical indications, for example, in the case of mesenchymal chondrosarcoma, for which trabectedin has been reported to be exceptionally active. The possibility of combining trabectedin with targeted therapies, immune checkpoint inhibitors or virotherapy would also be an interesting concept. In short, trabectedin is an old new drug with proven potential to impact the lives of patients with soft tissue sarcoma and other solid malignancies.

Funding: Sarcoma Oncology Center, Santa Monica, CA 90405.

Complete response after rechallenge with trabectedin in a patient with previously responding high-grade undifferentiated sarcoma

Evidence supporting rechallenge in patients responding to first exposure to trabectedin is limited. We report on a 39-year-old woman with advanced high-grade undifferentiated sarcoma (US) retreated twice with trabectedin after first response. The patient presented in June 2006 with an abdominal mass originating from the rear fascia of the rectus abdominis. Staging examinations did not indicate metastases and she underwent surgery; pathology showed a high-grade (FNCLCC G3) US. Subsequently, the patient received five cycles of adjuvant chemotherapy with epirubicin and ifosfamide. In February 2009 a computed tomography (CT) scan showed an abdominal mass involving the transverse mesocolon. R0 surgery was performed. In September 2009, peritoneal lesions appeared. Trabectedin was initiated at a dose of 1.5 mg/m² by a 24 h intravenous infusion every 3 weeks, without relevant toxicity. After six cycles (March 2010), CT and PET-CT scans showed complete disappearance of metastases. In February 2012, new secondary lesions in the subdiaphragmatic region and a peritoneal lesion appeared. We rechallenged the patient with the same schedule of trabectedin; a complete response was achieved after two cycles. In October 2013, new secondary lesions in the subdiaphragmatic region and a retroperitoneal lesion were found. We rechallenged with the same schedule of trabectedin; PET-CT scans after two cycles showed complete response on the subdiaphragmatic lesion. Radiotherapy on the retroperitoneal lesion was performed. The patient underwent a total of 18 cycles and remains free from radiologically detectable disease. We report complete radiological remission after two rechallenges with trabectedin in a patient with previously responding high-grade US.

Long-term response to first-line trabectedin in an elderly female patient with a metastatic leiomyosarcoma unfit for anthracycline

Systemic chemotherapy comprising anthracycline monotherapy is the standard regimen for metastatic soft tissue sarcomas, particularly leiomyosarcomas, which have limited sensitivity to ifosfamide. However, the optimal chemotherapy regimen for elderly patients, especially those considered unfit for anthracyclines, is undefined. Trabectedin is a potent marine-derived antineoplastic drug with documented activity in liposarcomas and leiomyosarcomas. It is registered in Europe for the treatment of adult patients with advanced soft tissue sarcoma, after failure of anthracyclines and ifosfamide, or who are unsuited to receive these agents. We report the long-term response to first-line trabectedin therapy in an elderly patient with metastatic leiomyosarcoma unfit for standard therapy. A 66-year-old woman underwent resection of a pelvic epithelioid leiomyosarcoma with positive margins in December 2002, followed by postoperative radiotherapy. In February 2012, she was diagnosed with multiple lung lesions and local relapse in the pelvis. As she was considered unsuitable for both anthracycline and ifosfamide because of cardiovascular comorbidities and because she was highly anxious at the prospect of developing alopecia, vomiting, and fatigue, we commenced treatment with trabectedin at 75% of the standard dose of 1.5 mg/m² every 3 weeks. Treatment was well tolerated, and the patient continued treatment for 25 cycles, with disease stabilization according to the RECIST criteria and a partial response according to the Choi criteria. Disease progression was observed in November 2013 and the patient died 20 months after the diagnosis of metastases. Trabectedin may represent an alternative option for highly selected elderly patients with metastatic sarcoma and unfit for anthracyclines; careful monitoring of toxicities is strongly recommended.

Overall Survival and Response to Systemic Therapy in Metastatic Extrauterine Leiomyosarcoma

Background. Leiomyosarcomas (LMS) represent a heterogeneous subset of soft tissue sarcomas. Factors influencing prognosis for patients with metastatic extrauterine LMS (euLMS) are not well described. Limited data are available regarding responses to systemic therapy. Methods. We collected clinical and pathologic information for all patients with metastatic euLMS seen at Memorial Sloan Kettering Cancer Center between 1989 and 2012. Objective responses to first-line therapy were analyzed for a subset of patients with available baseline and on-treatment imaging using RECIST 1.1. Results. 215 patients with metastatic euLMS had a median overall survival (OS) of 2.6 years from the time of metastasis. Older age, male sex, and ≥3 initial sites of metastasis were associated with worse OS on multivariate analysis. Objective response rate (ORR) in N = 113 was 19% overall and 25%, 26%, and 25% for gemcitabine, gemcitabine plus docetaxel, and anthracycline-alkylator combinations. Patients whose tumors objectively responded to first-line therapy had a lower risk of death versus those who did not (Hazard Ratio 0.46; 95% CI: 0.26–0.79, p = 0.005). Conclusions. Anthracycline- and gemcitabine-based regimens have similar activity in this cohort of euLMS. Prognostic factors for OS include older age, male sex, and ≥3 initial sites.

Marine Invertebrate Metabolites with Anticancer Activities: Solutions to the "Supply Problem"

Marine invertebrates provide a rich source of metabolites with anticancer activities and several marine-derived agents have been approved for the treatment of cancer. However, the limited supply of promising anticancer metabolites from their natural sources is a major hurdle to their preclinical and clinical development. Thus, the lack of a sustainable large-scale supply has been an important challenge facing chemists and biologists involved in marine-based drug discovery. In the current review we describe the main strategies aimed to overcome the supply problem. These include: marine invertebrate aquaculture, invertebrate and symbiont cell culture, culture-independent strategies, total chemical synthesis, semi-synthesis, and a number of hybrid strategies. We provide examples illustrating the application of these strategies for the supply of marine invertebrate-derived anticancer agents. Finally, we encourage the scientific community to develop scalable methods to obtain selected metabolites, which in the authors' opinion should be pursued due to their most promising anticancer activities.

The value of trabectedin in the treatment of soft tissue sarcoma

Soft tissue sarcomas (STSs) are a group of rare tumors accounting for less than 1% of all adult malignant tumors, a heterogeneous group of more than 50 histological subtypes. Five percent to 30% of STS patients experience local recurrence and 10%–38% present with clinically detectable metastases. Doxorubicin either alone or in combination with ifosfamide has been used as first-line chemotherapy for advanced disease. After failure of first-line chemotherapy, high-dose ifosfamide, gemcitabine + docetaxel, and dacarbazine may be applicable, although high-level evidence is lacking. Trabectedin is a synthetic, marine-derived alkylating agent derived from the Caribbean tunicate, Ecteinascidia turbinata. Several clinical trials have shown that trabectedin has a favorable toxicity profile and is an alternative therapeutic option in adult patients with advanced STS who have not responded to treatment with doxorubicin and ifosfamide. Several clinical trials also recommend the 24-hour intravenous infusion every 3 weeks regimen. The most frequently reported grade 3/4 adverse events were neutropenia and elevated serum levels of AST/ALT. Steroid pretreatment is an effective way of reducing the extent of hepatotoxicity, and steroids are now given routinely before trabectedin administration. Further studies are ongoing to evaluate the efficacy and safety of combination therapy of trabectedin with other agents.

Marine Drugs Regulating Apoptosis Induced by Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL)

Marine biomass diversity is a tremendous source of potential anticancer compounds. Several natural marine products have been described to restore tumor cell sensitivity to TNF-related apoptosis inducing ligand (TRAIL)-induced cell death. TRAIL is involved during tumor immune surveillance. Its selectivity for cancer cells has attracted much attention in oncology. This review aims at discussing the main mechanisms by which TRAIL signaling is regulated and presenting how marine bioactive compounds have been found, so far, to overcome TRAIL resistance in tumor cells.