Efficacy and safety of trabectedin or dacarbazine in patients with advanced uterine leiomyosarcoma after failure of anthracycline-based chemotherapy: Subgroup analysis of a phase 3, randomized clinical trial

Current Treatment Options: Uterine Sarcoma

OPINION STATEMENT

The cornerstone of treatment for uterine sarcoma, regardless of histologic type, remains en bloc surgical resection with total hysterectomy. In the case of incidental diagnosis during another procedure, such as myomectomy, where a hysterectomy was not performed initially, completion hysterectomy or cervical remnant removal is recommended. The completion of additional surgical procedures, including bilateral salpingo-oophorectomy and lymphadenectomy, remains nuanced. Bilateral salpingo-oophorectomy remains controversial in the setting of most subtypes of uterine sarcoma, except in the case of hormone-receptor positivity, such as in low grade endometrial stromal sarcoma, where it is indicated as part of definitive surgical treatment. In the absence of apparent nodal involvement, we do not recommend performing universal lymphadenectomy for patients with sarcoma. We recommend systemic therapy for patients with extra-uterine or advanced stage disease, high-grade histology, and recurrence. The most active chemotherapy regimens for advanced, high-grade disease remain doxorubicin or gemcitabine and docetaxol combination therapy. A notable exception is low grade endometrial stromal sarcoma, where we recommend anti-hormonal therapy in the front-line setting. Radiation therapy is reserved for selected cases where it can aid in palliating symptoms.

Patient-reported outcomes in randomized clinical trials of systemic therapy for advanced soft tissue sarcomas in adults: A systematic review

BACKGROUND

This systematic review evaluates reporting of patient-reported outcomes (PROs) within randomized clinical trials (RCTs) for advanced soft tissue sarcoma (STS) patients.

METHODS

A systematic literature search from January 2000 - August 2022 was conducted for phase II/III RCTs evaluating systemic treatments in adult patients with advanced STS. Quality of PRO reporting was assessed using the CONSORT PRO extension.

RESULTS

Out of 7294 abstracts, 59 articles were included; comprising 43 RCTs. Only 15 RCTs (35%) included PROs, none as primary endpoints. Only 10 of these RCTs reported PROs, either in the primary (6/10) or secondary publication (1/10) or in both (3/10), with a median time interval of 23 months. The median CONSORT PRO adherence score was 5.5/14, with higher scores in publications focusing exclusively on PROs.

CONCLUSION

These results highlight the need for improved and more consistent PRO reporting to inform patient care in the setting of advanced STS.

Phase Ib Study of Unesbulin (PTC596) Plus Dacarbazine for the Treatment of Locally Recurrent, Unresectable or Metastatic, Relapsed or Refractory Leiomyosarcoma

PURPOSE

This multicenter, single-arm, open-label, phase Ib study was designed to determine the recommended phase II dose (RP2D) and to evaluate the safety and preliminary efficacy of unesbulin plus dacarbazine (DTIC) in patients with advanced leiomyosarcoma (LMS).

PATIENTS AND METHODS

Adult subjects with locally advanced, unresectable or metastatic, relapsed or refractory LMS were treated with escalating doses of unesbulin orally twice per week in combination with DTIC 1,000 mg/m2 intravenously (IV) once every 21 days. The time-to-event continual reassessment method was used to determine the RP2D on the basis of dose-limiting toxicities (DLTs) assessed during the first two 21-day treatment cycles. All explored doses of unesbulin (200 mg up to 400 mg) were in combination with DTIC. An expansion cohort was enrolled to evaluate the safety and efficacy of unesbulin at the RP2D.

RESULTS

Unesbulin 300 mg administered orally twice per week in combination with DTIC 1,000 mg/m2 IV once every 21 days was identified as the RP2D. On the basis of data from 27 subjects who were deemed DLT-evaluable, toxicity was higher in the unesbulin 400 mg group, with three of four subjects (75%) experiencing DLTs versus one of four subjects (25%) in the 200 mg group and three of 19 subjects (15.8%) in the 300 mg group. The most commonly reported DLTs and treatment-related grade 3 and 4 adverse events were thrombocytopenia and neutropenia. At the RP2D, seven subjects who were efficacy evaluable achieved partial response for an objective response rate of 24.1%.

CONCLUSION

Unesbulin 300 mg twice per week plus DTIC 1,000 mg/m2 once every 21 days was identified as the RP2D, demonstrating a favorable benefit-risk profile in a heavily pretreated population of adults with advanced LMS.

Uterine leiomyosarcoma cell-derived extracellular vesicles induce the formation of cancer-associated fibroblasts

OBJECTIVE

Uterine leiomyosarcoma (ULMS) is a rare malignant tumor, which is aggressive, and has a poor prognosis even during its early stages. Extracellular vesicles (EVs) carry cargo, such as microRNAs (miRNAs), which are involved in intercellular communication in the tumor microenvironment and other processes. Because there are no studies on EV-related miRNAs in ULMS, we identified EV-related miRNAs in ULMS and examined their function.

METHODS

Small EVs (sEVs) and medium/large EVs (m/lEVs) were extracted from ULMS cells by ultracentrifugation and their basic characteristics were evaluated. Then, small RNA sequencing was done to obtain EV-related miRNA profiles. Next, miRNA expression levels in sera and tissues of ULMS patients were compared with those of myoma patients.

RESULTS

miR-654-3p and miR-369-3p were indicated to be highly expressed in both sera and tissues of ULMS patients. These two miRNAs are also highly expressed in ULMS cell lines and ULMS-derived EVs. Some cancer-associated fibroblast (CAF) markers were increased when fibroblasts were treated with ULMS-derived EVs. Furthermore, fibroblasts took up EVs derived from ULMS as determined by confocal laser microscopy. In addition, the transfection of the two candidate miRNAs into fibroblasts significantly increased some CAF markers, particularly ACTA2.

CONCLUSION

miR-654-3p and miR-369-3p are highly expressed in ULMS-derived EVs, indicating that these EV-related miRNAs induce the formation of cancer-associated fibroblasts.

Trabectedin and Radiotherapy in Endometrial Stromal Sarcoma: A Case Report

Introduction

Endometrial stromal sarcoma (ESS) is a rare tumor that remains a diagnostic and therapeutic challenge to physicians worldwide. The metastatic setting implies a poor prognosis, with a 5-year survival rate below 40%. Patients with advanced-stage high-grade ESS (HG-ESS) have limited therapeutic options, often involving various chemotherapy regimens.

Case Presentation

This report depicts the case of a 47-year-old female diagnosed with HG-ESS. She underwent several lines of treatment starting with radiotherapy and brachytherapy, followed by multiple lines of treatment including trabectedin over several months. After retreatment with trabectedin and achieving disease stabilization for 10 months, treatment was optimized by trabectedin combined with radiotherapy, leading to stable disease that is still ongoing and lasts for over 17 months.

Conclusion

Our case underscores the challenging nature of treating patients with HG-ESS and highlights the safety of long-term retrial with trabectedin, coupled with radiotherapy administration. This approach maintained a durable stable disease response in the metastatic setting.

Phase II Study of Olaparib and Temozolomide for Advanced Uterine Leiomyosarcoma (NCI Protocol 10250)

PURPOSE

Uterine leiomyosarcoma (uLMS) is an aggressive subtype of soft-tissue sarcoma with frequent metastatic relapse after curative surgery. Chemotherapy provides limited benefit for advanced disease. Multiomics profiling studies have identified homologous recombination deficiency in uLMS. In preclinical studies where olaparib and temozolomide provided modest activity, the combination was highly effective for inhibiting uLMS tumor growth.

PATIENTS AND METHODS

NCI Protocol 10250 is a single-arm, open-label, multicenter, phase II study evaluating olaparib and temozolomide in advanced uLMS. Patients with progression on ≥1 prior line received temozolomide 75 mg/m2 orally once daily with olaparib 200 mg orally twice a day both on days 1-7 in 21-day cycles. The primary end point was the best objective response rate (ORR) within 6 months. A one-stage binomial design was used. If ≥5 of 22 responded, the treatment would be considered promising (93% power; α = .06). All patients underwent paired biopsies that were evaluated with whole-exome sequencing (WES)/RNAseq and a RAD51 foci formation assay.

RESULTS

Twenty-two patients were evaluable. The median age was 55 years, and 59% had received three or more prior lines. Best ORR within 6 months was 23% (5 of 22). The overall ORR was 27% (6 of 22). The median progression-free survival (mPFS) was 6.9 months (95% CI, 5.4 months to not estimable). Hematologic toxicity was common (grade 3/4 neutropenia: 75%; thrombocytopenia: 32%) but manageable with dose modification. Five of 16 (31%) of tumors contained a deleterious homologous recombination gene alteration by WES, and 9 of 18 (50%) were homologous recombination-deficient by the RAD51 assay. In an exploratory analysis, mPFS was prolonged for patients with homologous recombination-deficient versus homologous recombination-proficient tumors (11.2 v 5.4 months, P = .05) by RAD51.

CONCLUSION

Olaparib and temozolomide met the prespecified primary end point and provided meaningful clinical benefit in patients with advanced, pretreated uLMS.

Downregulation of miR‑10b‑5p facilitates the proliferation of uterine leiomyosarcoma cells: A microRNA sequencing‑based approach

Uterine leiomyosarcoma (ULMS) is one of the most aggressive gynecological malignancies. In addition, the molecular background of ULMS has not been fully elucidated due to its low incidence. Therefore, no effective treatment strategies have been established based on its molecular background. The present study aimed to investigate the roles of microRNAs (miRNAs/miRs) in the development of ULMS. Comprehensive miRNA sequencing was performed using six ULMS and three myoma samples, and revealed 53 and 11 significantly upregulated and downregulated miRNAs, respectively. One of the most abundant miRNAs in myoma samples was miR‑10b‑5p. The mean normalized read count of miR‑10b‑5p was 93,650 reads in myoma, but only 27,903 reads in ULMS. Subsequently, to investigate the roles of miR‑10b‑5p, gain‑of‑function analysis was performed using SK‑UT‑1 and SK‑LMS‑1 cell lines. The overexpression of miR‑10b‑5p suppressed cell proliferation and reduced the number of colonies. Moreover, miR‑10b‑5p increased the number of cells in the G1 phase. In conclusion, tumor‑suppressive miR‑10b‑5p was significantly downregulated in ULMS compared with in myoma; thus, miR‑10b‑5p may serve a specific role in sarcoma progression.

Evaluation of the efficacy of systemic therapy for advanced uterine leiomyosarcoma: A systematic review, meta-analysis, and meta-regression analysis

Uterine leiomyosarcoma (uLMS) is an aggressive mesenchymal neoplasm associated with a poor prognosis. Systemic chemotherapy is the standard therapy for patients with uLMS. However, it is unclear which treatment regimen results in the most favorable clinical outcome. We performed a meta-analysis and meta-regression analysis to assess the efficiency of different treatments received by patients with advanced, metastatic, and relapsing uLMS by evaluating the objective response rate (ORR) and disease control rate (DCR) as primary endpoints. The frequentist random effects meta-analysis model was used to compare the outcomes of different treatment regimens for advanced uLMS. A meta-regression analysis was performed to estimate the association between the study-specific hazard ratios and specific demographic variables. A meta-analysis of 51 reports including 1664 patients was conducted. Among patients who received adjuvant chemotherapy (916 patients; 55%), gemcitabine and docetaxel were the most frequently used drugs. First-line monotherapy with alkylating agents (pooled ORR = 0.48; 95% confidence interval [CI]: 0.44-0.52) and second-line monotherapy with protein kinase inhibitors (pooled ORR = 0.45; 95% CI: 0.39-0.52) resulted in favorable prognoses. The combinations of anthracycline plus alkylating therapy (pooled DCR = 0.74; 95% CI: 0.67-0.79) and of gemcitabine plus docetaxel (pooled DCR = 0.70; 95% CI: 0.63-0.75) showed the greatest benefits when used as first-line and second-line chemotherapies, respectively. Subgroup meta-analysis results revealed that dual-regimen therapies comprising anthracycline plus alkylating therapy and gemcitabine plus docetaxel are practical therapeutic choices for International Federation of Gynecology and Obstetrics stages III-IVb with distant metastases when assessed by computed tomography (p = 0.001). Furthermore, neoadjuvant chemotherapy and local radiotherapy resulted in favorable outcomes for patients with earlier stages of distant relapsed uLMS (p < 0.001). Our findings provide a basis for designing new therapeutic strategies and can potentially guide clinical practice toward better prognoses for uLMS patients with advanced, metastatic, and relapsing disease.

Uterine sarcomas: clinical practice guidelines for diagnosis, treatment, and follow-up, by Spanish group for research on sarcomas (GEIS)

Uterine sarcomas are very infrequent and heterogeneous entities. Due to its rarity, pathological diagnosis, surgical management, and systemic treatment are challenging. Treatment decision process in these tumors should be taken in a multidisciplinary tumor board. Available evidence is low and, in many cases, based on case series or clinical trials in which these tumors have been included with other soft tissue sarcoma. In these guidelines, we have tried to summarize the most relevant evidence in the diagnosis, staging, pathological disparities, surgical management, systemic treatment, and follow-up of uterine sarcomas.

Therapeutic advances in leiomyosarcoma

Leiomyosarcoma is an aggressive mesenchymal malignancy and represents one of the most common subtypes of soft tissue sarcomas. It is characterized by significant disease heterogeneity with variable sites of origin and diverse genomic profiles. As a result, the treatment of advanced leiomyosarcoma is challenging. First-line therapy for metastatic and/or unresectable leiomyosarcoma includes anthracycline or gemcitabine based regimens, which provide a median progression-free survival time of about 5 months and overall survival time between 14-16 months. Effective later-line therapies are limited. Molecular profiling has enhanced our knowledge of the pathophysiology driving leiomyosarcoma, providing potential targets for treatment. In this review, we explore recent advances in our understanding of leiomyosarcoma tumor biology and implications for novel therapeutics. We describe the development of clinical trials based on such findings and discuss available published results. To date, the most promising approaches for advanced leiomyosarcoma include targeting DNA damage repair pathways and aberrant metabolism associated with oncogenesis, as well as novel chemotherapy combinations. This review highlights the recent progress made in the treatment of advanced leiomyosarcoma. Ongoing progress is contingent upon further development of clinical trials based on molecular findings, with careful consideration for clinical trial design, strong academic collaborations, and prospective correlative analyses.

Trabectedin induces ferroptosis via regulation of HIF-1α/IRP1/TFR1 and Keap1/Nrf2/GPX4 axis in non-small cell lung cancer cells

BACKGROUND AND OBJECTIVES

Non-small cell lung cancer (NSCLC) is a global health concern. NSCLC treatment outcomes are generally poor due to treatment resistance or toxicity. Ferroptosis is a novel cell death triggered by iron accumulation, reactive oxygen species (ROS), and lipid peroxidation. Ferroptosis may kill cancer cells, particularly those resistant to apoptosis.

MATERIALS AND METHODS

The Cell Counting Kit-8 assay assessed NSCLC cell viability after trabectedin treatment. Flow cytometry with Annexin V-FITC staining evaluated cell death. ROS, iron, lipid peroxidation, and GSH levels were measured using commercial kits. qRT-PCR and western blots evaluated messenger RNA and protein levels. Proteins were inhibited using short interfering RNA transfection and specific inhibitors.

RESULTS

Trabectedin was cytotoxic to NSCLC cells regardless of p53 status. Trabectedin upregulated iron, ROS, and lipid peroxidation in NSCLC cells, causing ferroptosis. Trabectedin increases iron and ROS levels by upregulating transferrin receptor 1 and the HIF-1/IRP1 axis. In NSCLC cells, trabectedin suppresses glutathione peroxidase 4, followed by the Keap1/Nrf2 axis.

CONCLUSIONS

Our findings imply that trabectedin may treat NSCLC effectively.

Trabectedin and lurbinectedin: Mechanisms of action, clinical impact, and future perspectives in uterine and soft tissue sarcoma, ovarian carcinoma, and endometrial carcinoma

The ecteinascidins trabectedin and lurbinectedin are very interesting antineoplastic agents, with a favorable toxicity profile and peculiar mechanisms of action. These drugs form adducts in the minor groove of DNA, which produce single-strand breaks (SSBs) and double-strand breaks (DSBs) and trigger a series of events resulting in cell cycle arrest and apoptosis. Moreover, the ecteinascidins interact with the tumor microenvironment, reduce the number of tumor-associated macrophages, and inhibit the secretion of cytokines and chemokines. Trabectedin has been approved by the Federal Drug Administration (FDA) for patients with unresectable or metastatic liposarcoma or leiomyosarcoma who received a prior anthracycline-based regimen. Moreover, trabectedin in combination with pegylated liposomal doxorubicin (PLD) has been approved in the European Union for the treatment of platinum-sensitive recurrent ovarian cancer. Lurbinectedin has been approved by the FDA for patients with metastatic small cell lung cancer with disease progression on or after platinum-based chemotherapy. The review assesses in vitro and in vivo experimental studies on the antineoplastic effects of both ecteinascidins as well as the clinical trials on the activity of trabectedin in uterine sarcoma and ovarian carcinoma and of lurbinectedin in ovarian carcinoma and endometrial carcinoma.

Being the ultimate travel companion of a patient with uterine leiomyosarcoma

Uterine fibroids are difficult to distinguish from malignant masses using standard ultrasonography; and morcellation carries the risk of disseminating occult cancer in a small but relevant group of women with an undetected uterine malignancy. In this context, we follow the progress of a woman diagnosed with uterine leiomyosarcoma after suboptimal initial surgery for an assumed fibroid. Evidence is reviewed that guided multidisciplinary tumor board decisions about optimal management approaches after local seeding and development of distant metastases, and informed treatment selection at each line of therapy. As the case study illustrates, choice of treatment for advanced soft tissue sarcomas frequently involves finding an appropriate balance between the efficacy and toxicity of available options, aiming to allow patients to maintain their normal lives.

Trabectedin in Cancers: Mechanisms and Clinical Applications

Trabectedin, a tetrahydroisoquinoline alkaloid, is the first marine antineoplastic agent approved with special anticancer mechanisms involving DNA binding, DNA repair pathways, transcription regulation and regulation of the tumor microenvironment. It has favorable clinical applications, especially for the treatment of patients with advanced soft tissue sarcoma, who failed in anthracyclines and ifosfamide therapy or could not receive these agents. Currently, trabectedin monotherapy regimen and regimens of combined therapy with other agents are both widely used for the treatment of malignancies, including soft tissue sarcomas, ovarian cancer, breast cancer, and non-small-cell lung cancer. In this review, we summarized the basic information and some updated knowledge on trabectedin, including its molecular structure, metabolism in various cancers, pharmaceutical mechanisms, clinical applications, drug combination, and adverse reactions, along with prospections on its possibly more optimal use in cancer treatment.

Aberrant Activation of Cell-Cycle-Related Kinases and the Potential Therapeutic Impact of PLK1 or CHEK1 Inhibition in Uterine Leiomyosarcoma

PURPOSE

Uterine leiomyosarcoma is among the most aggressive gynecological malignancies. No effective treatment strategies have been established. This study aimed to identify novel therapeutic targets for uterine leiomyosarcoma based on transcriptome analysis and assess the preclinical efficacy of novel drug candidates.

EXPERIMENTAL DESIGN

Transcriptome analysis was performed using fresh-frozen samples of six uterine leiomyosarcomas and three myomas. The Ingenuity Pathway Analysis (IPA) was used to identify potential therapeutic target genes for uterine leiomyosarcoma. Afterward, our results were validated using three independent datasets, including 40 uterine leiomyosarcomas. Then, the inhibitory effects of several selective inhibitors for the candidate genes were examined using SK-UT-1, SK-LMS-1, and SKN cell lines.

RESULTS

We identified 512 considerably dysregulated genes in uterine leiomyosarcoma compared with myoma. The IPA revealed that the function of several genes, including CHEK1 and PLK1, were predicted to be activated in uterine leiomyosarcoma. Through an in vitro drug screening, PLK1 or CHEK1 inhibitors (BI-2536 or prexasertib) were found to exert a superior anticancer effect against cell lines at low nanomolar concentrations and induce cell-cycle arrest. In SK-UT-1 tumor-bearing mice, BI-2536 monotherapy remarkably suppressed tumorigenicity. Moreover, the prexasertib and cisplatin combination therapy inhibited tumor proliferation and prolonged the time to tumor progression.

CONCLUSIONS

We identified upregulated expressions of PLK1 and CHEK1; their kinase activity was activated in uterine leiomyosarcoma. BI-2536 and prexasertib demonstrated a significant anticancer effect. Therefore, cell-cycle-related kinases may present a promising therapeutic strategy for the treatment of uterine leiomyosarcoma.

Role of Homologous Recombination Repair (HRR) Genes in Uterine Leiomyosarcomas: A Retrospective Analysis

Simple Summary

A more in-depth molecular characterization of uterine leiomyosarcomas (uLMS), a rare disease characterized with dismal prognosis, could provide data suitable for the identification of potential target-based drugs. We aimed to define frequencies of gene alterations in uLMS, especially regarding the somatic mutations of BRCA and HRR gene alterations, and identify the impact of these molecular alterations on clinical outcomes. This retrospective analysis of the mutational profile of uLMS showed that the most frequent alterations involved the TP53 gene, and that patients with TP53 alterations experienced a worse prognosis compared to patients with wild-type TP53 genes. Conversely, patient clinical outcomes were similar within patients with BRCA- and HRR-related genes versus non-HRR-related genes. However, although the frequency of patients with BRCA- and HRR-related alterations and mutations was relatively small, this setting could deserve an investigation into drug actionability, and potentially benefit from PARP inhibitors.

Abstract

Uterine leiomyosarcomas (uLMS) is a very rare disease, and patients experience a dismal prognosis even when treated with chemotherapy. Therefore, a more in-depth molecular characterization of this disease could provide suitable data for the identification of potential target-based drugs. This retrospective, single institutional study aimed to define the frequencies of gene alterations in uLMS, especially regarding the somatic mutations of BRCA and Homologous Recombination Repair (HRR) genes, and the impact of molecular alterations on clinical outcomes. The 16-genes Next-Generation Sequencing (NGS) panel, Homologous Recombination Solution TM (HRS, Sophia Genetics, Saint Sulpice, Switzerland), was used for the molecular evaluation of samples. The majority of patients (66/105, 63%) carried at least one sequence alteration, with a prevalence of TP53 involvement followed by RAD51B, BRCA1/2, and FANCL. Patients with TP53 gene alterations experienced a significantly worse prognosis for progression free survival (PFS) and overall survival (OS) versus wild-type patients. Given the number of patients with the BRCA1/2 mutation (N = 12), we included them in the HRR patient group; there was no difference in clinical outcomes with HRR versus non-HRR. The Cox’s multivariate analysis showed that stage and TP53 gene alterations resulted in a significantly worse OS. The integration of gene networking data, such as tumor mutation burdens and cancer driver gene identification, could show a clearer discrimination of gene distribution patterns, and lead to the implementation of therapeutic targets.

Novel Therapeutics in the Treatment of Uterine Sarcoma

Uterine sarcomas reflect the diversity of sarcoma as a whole. The most common histologies include leiomyosarcoma, high- and low-grade endometrial stromal sarcoma, and adenosarcoma. These are clinically and biologically heterogeneous diseases that are challenging to treat in the advanced setting. Recent advances in our understanding of the cancer biology of uterine sarcomas has improved diagnostic evaluation and therapeutic management. Promising approaches for patients with advanced uterine leiomyosarcoma include targeting DNA damage repair pathways and depleting immunosuppressive macrophage populations. A subset of endometrial stromal sarcomas harbor potentially actionable alterations in the Wnt, cyclin D-CDK4/6-Rb, and MDM2-p53 pathways. There remains an urgent need to translate molecular findings into prospective clinical trials of novel agents for patients with these diseases; progress will depend on academic collaborations and enrollment of patients with uterine sarcoma in biomarker-driven basket studies.

A Phase 1/2 Trial Combining Avelumab and Trabectedin for Advanced Liposarcoma and Leiomyosarcoma

PURPOSE

Leiomyosarcoma (LMS) and liposarcoma (LPS) frequently express PD-L1 but are generally resistant to PD-1/PD-L1 inhibition (ICI). Trabectedin is FDA-approved for LMS and LPS. This study aimed to evaluate the safety and efficacy of trabectedin with anti-PD-L1 antibody avelumab in patients with advanced LMS and LPS.

PATIENTS AND METHODS

A single-arm, open-label, Phase 1/2 study tested avelumab with trabectedin for advanced LMS and LPS. The phase I portion evaluated safety and feasibility of trabectedin (1, 1.2 and 1.5 mg/m2) with avelumab at standard dosing. Primary endpoint of the phase II portion was objective response rate (ORR) by RECIST 1.1. Correlative studies included T-cell receptor sequencing (TCRseq), multiplex immunohistochemistry, and tumor gene expression.

RESULTS

33 patients were evaluable; 24 with LMS (6 uterine and 18 non-uterine) and 11 with LPS. In Phase 1, dose limiting toxicities (DLTs) were observed in 2 of 6 patients at both trabectedin 1.2 and 1.5 mg/m2. The recommended Phase 2 dose (RP2D) was 1.0 mg/m2 trabectedin and 800 mg avelumab. Of 23 patients evaluable at RP2D, three (13%) had partial response (PR), ten (43%) had stable disease (SD) as best response. 6-month PFS was 52%; median PFS was 8.3 months. Patients with PR had higher Simpson Clonality score on TCRseq from peripheral blood mononuclear cells (PBMC) versus those with SD (0.182 vs 0.067, p = 0.02) or PD (0.182 vs 0.064, p = 0.01).

CONCLUSIONS

Although the trial did not meet the primary ORR endpoint, PFS compared favorably to prior studies of trabectedin warranting further investigation.

What Clinical Trials Are Needed for Treatment of Leiomyosarcoma?

OPINION STATEMENT

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.

New Aspects of Sarcomas of Uterine Corpus-A Brief Narrative Review

Sarcomas of the uterine corpus are rare malignant neoplasms, which are further classified into mesenchymal tumors, and mixed (epithelial plus mesenchymal) tumors. The main issues concerning these neoplasms are the small number of clinical trials, insufficient data from evidence-based medicine, insignificant interest from the pharmaceutical industry, all of which close a vicious circle. The low frequency of these malignancies implies insufficient experience in the diagnosis, hence incomplete surgical and complex treatment. Additionally, the rarity of these sarcomas makes it very difficult to develop clinical practice guidelines. Preoperative diagnosis, neoadjuvant and adjuvant chemoradiation, target and hormone therapies still raise many controversies. Disagreements about the role and type of surgical treatment are also often observed in medical literature. There are still insufficient data about the role of pelvic lymph node dissection and fertility-sparing surgery. Pathologists’ experience is of paramount importance for an accurate diagnosis. Additionally, genetics examinations become part of diagnosis in some sarcomas of the uterine corpus. Some gene mutations observed in uterine sarcomas are associated with different outcomes. Therefore, a development of molecular classification of uterine sarcomas should be considered in the future. In this review, we focus on the epidemiology, pathogenesis, pathology, diagnosis and treatment of the following sarcomas of the uterine corpus: leiomyosarcoma, low- and high-grade endometrial stromal sarcomas, undifferentiated sarcoma and adenosarcoma. Uterine carcinosarcomas are excluded as they represent an epithelial tumor rather than a true sarcoma.

Leiomyosarcoma: Does Location of Primary Help to Determine the Best Systemic Therapy Options?

OPINION STATEMENT

Management of leiomyosarcoma is based on the specifics of each individual case. Specifically, the location of the disease and whether the disease is metastatic or localized and if localized disease, whether the tumor is resectable or unresectable. In patients with recurrent or metastatic disease, factors such as disease-free interval and pattern of spread should be considered within the context of treatment planning. In general, patients with metastatic disease are typically treated with systemic chemotherapy with either an anthracycline-based regimen or gemcitabine-based regimen as first-line therapy. Additional systemic options include trabectedin, pazopanib, eribulin, and DTIC. Uterine LMS has been the most studied site-specific LMS with respect to systemic therapy. The increasing use of tumor genomics may ultimately define subsets which may benefit from tailored systemic therapies.

RNA Sequencing for Personalized Treatment of Metastatic Leiomyosarcoma: Case Report

Uterine leiomyosarcoma (UL) is a rare malignant tumor that develops from the uterine smooth muscle tissue. Due to the low frequency and lack of sufficient data from clinical trials there is currently no effective treatment that is routinely accepted for UL. Here we report a case of a 65-years-old female patient with metastatic UL, who progressed on ifosfamide and doxorubicin therapy and developed severe hypertensive crisis after administration of second line pazopanib, which lead to treatment termination. Rapid progression of the tumor stressed the need for the alternative treatment options. We performed RNA sequencing and whole exome sequencing profiling of the patient's biopsy and applied Oncobox bioinformatic algorithm to prioritize targeted therapeutics. No clinically relevant mutations associated with drug efficiencies were found, but the Oncobox transcriptome analysis predicted regorafenib as the most effective targeted treatment option. Regorafenib administration resulted in a complete metabolic response which lasted for 10 months. In addition, RNA sequencing analysis revealed a novel cancer fusion transcript of YWHAE gene with fusion partner JAZF1. Several chimeric transcripts for YWHAE and JAZF1 genes were previously found in uterine neoplasms and some of them were associated with tumor prognosis. However, their combination was detected in this study for the first time. Taken together, these findings evidence that RNA sequencing may complement analysis of clinically relevant mutations and enhance management of oncological patients by suggesting putative treatment options.

Trabectedin (Yondelis®) as a Therapeutic Option in Gynecological Cancers: A Focus on its Mechanisms of Action, Clinical Activity and Genomic Predictors of Drug Response

The use of predictive biomarkers provides potential individualized cancer therapeutic options to prevent therapy failure as well as serious toxicities. Several recent studies showed that predictive and prognostic biomarkers are a notable personalized strategy to improve patients' care in several cancers. Trabectedin (Yondelis®) is a cytotoxic agent, derived from a marine organism, harbouring a significant antitumor activity against several cancers such as soft tissue sarcoma, ovarian, and breast cancers. Recently and with the advent of molecular genetic testing, BRCA mutational status was found as an important predictor of response to this anticancer drug, especially in gynecological cancers. The aim of this updated review is to discuss the mechanisms of action of trabectedin against the wellknown cancer hallmarks described until today. The current advances were also examined related to genomic biomarkers that can be used in the future to predict the efficacy of this potent anticancer natural molecule in various gynecological cancers.

The systemic treatment of uterine leiomyosarcomas: A systematic review. No news is good news?

BACKGROUND

Uterine leiomyosarcomas are rare malignant mesenchymal tumors. The systemic treatment of these tumors includes chemotherapy and radiotherapy. However, there are still a lot of unanswered questions regarding the ideal therapeutic approach.

METHODS

We have conducted a systematic review of the treatment strategies of uterine leiomyosarcomas for the last ten years.

RESULTS

Adjuvant chemotherapy is still a matter of dilemma. Doxorubicin based chemotherapy or the combination of Gemcitabine-Docetaxel are the regimens of choice for the first line setting. Beyond the first line, there are several options;, including chemotherapy, targeted therapy, and recently efforts of introducing immunotherapy to the therapeutic armamentarium of clinicians treating uterine leiomyosarcomas.

CONCLUSIONS

Despite the efforts of the clinicians dealing with uterine leiomyosarcomas, the optimal therapeutic algorithm is yet to be described.

Unmet Medical Needs and Future Perspectives for Leiomyosarcoma Patients-A Position Paper from the National LeioMyoSarcoma Foundation (NLMSF) and Sarcoma Patients EuroNet (SPAEN)

As leiomyosarcoma patients are challenged by the development of metastatic disease, effective systemic therapies are the cornerstone of outcome. However, the overall activity of the currently available conventional systemic treatments and the prognosis of patients with advanced or metastatic disease are still poor, making the treatment of this patient group challenging. Therefore, in a joint effort together with patient networks and organizations, namely Sarcoma Patients EuroNet (SPAEN), the international network of sarcoma patients organizations, and the National LeioMyoSarcoma Foundation (NLMSF) in the United States, we aim to summarize state-of-the-art treatments for leiomyosarcoma patients in order to identify knowledge gaps and current unmet needs, thereby guiding the community to design innovative clinical trials and basic research and close these research gaps. This position paper arose from a leiomyosarcoma research meeting in October 2020 hosted by the NLMSF and SPAEN.

CD70 antibody-drug conjugate as a potential therapeutic agent for uterine leiomyosarcoma

BACKGROUND

Uterine leiomyosarcoma is a rare and aggressive gynecologic malignancy originating in the myometrium of the uterine corpus that tends to recur even after complete surgical excision. Current therapeutic agents have only modest effects on uterine leiomyosarcoma. Although antibodies and antibody-drug conjugates have been recognized as useful targeted therapies for other cancers, no study has yet evaluated the effects of this approach on uterine leiomyosarcoma.

OBJECTIVE

This study aimed to examine the activity of tumoral CD70 in uterine leiomyosarcoma and assess the antitumor activity of CD70-antibody-drug conjugate treatment in uterine leiomyosarcoma.

STUDY DESIGN

Target membrane proteins were screened by profiling and comparing membrane protein expression in 3 uterine leiomyosarcoma cell lines (SK-UT-1, SK-LMS-1, and SKN) and normal uterine myometrium cells using the isobaric tags for relative and absolute quantitation labeling method. Western blotting, fluorescence-activated cell sorting analyses, and immunohistochemistry were used to examine CD70 expression in the membrane proteins in uterine leiomyosarcoma cell lines and clinical samples. We developed an antibody-drug conjugate with a monoclonal antibody of the target membrane protein linked to monomethyl auristatin F and investigated its antitumor effects against uterine leiomyosarcoma (in vitro, in vivo, and in patient-derived xenograft models).

RESULTS

CD70 was identified as a specific antigen highly expressed in uterine leiomyosarcoma cell lines. Of the 3 uterine leiomyosarcoma cell lines, CD70 expression was confirmed in SK-LMS-1 cells by western blotting and fluorescence-activated cell sorting analysis. CD70 overexpression was observed in 19 of 21 (90.5%) tumor specimens from women with uterine leiomyosarcoma. To generate CD70-antibody-drug conjugate, anti-CD70 monoclonal antibody was conjugated with a novel derivative of monomethyl auristatin F. CD70-antibody-drug conjugate showed significant antitumor effects on SK-LMS-1 cells (half maximal inhibitory concentration, 0.120 nM) and no antitumor effects on CD70-negative uterine leiomyosarcoma cells. CD70-antibody-drug conjugate significantly inhibited tumor growth in the SK-LMS-1 xenograft mouse model (tumor volume, 129.8 vs 285.5 mm³; relative reduction, 54.5%; P<.001) and patient-derived xenograft mouse model (tumor volume, 128.1 vs 837.7 mm³; relative reduction, 84.7%; P<.001).

CONCLUSION

Uterine leiomyosarcoma tumors highly express CD70 and targeted therapy with CD70-antibody-drug conjugate may have a potential therapeutic implication in the treatment of uterine leiomyosarcoma.

Surgical and oncologic outcomes of hyperthermic intraperitoneal chemotherapy for uterine leiomyosarcoma: A systematic review of literature

OBJECTIVE

To examine the perioperative and survival outcomes in women with disseminated peritoneal uterine leiomyosarcoma (uLMS) who underwent cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

METHODS

A comprehensive systematic review of literature was conducted using multiple public search engines, PubMed, Scopus, and the Cochrane Library, in compliance with the PRISMA guidelines. Women with disseminated peritoneal uLMS treated with CRS-HIPEC were analyzed. Perioperative morbidity and mortality rate as well as oncologic outcomes related to CRS-HIPEC were assessed.

RESULTS

Ten studies met the inclusion criteria from 2004 to 2020, including 8 case series (n=28) and 2 original articles (n=47). Of the 75 patients, 68 (90.7%) were women with uLMS whereas 7 women were non-uLMS. Of these, 64 (85.3%) had recurrent disease, and 39 (52.0%) received chemotherapy or radiotherapy prior to CRS-HIPEC. The perioperative mortality rate was 4.0% (intraoperative 1.3%, and postoperative 2.7%), and postoperative complications (grade ≥3) rate ranged 21.4-22.2%. With regard to HIPEC regimens (n=75), cisplatin was most frequently used (n=55, 73.3%) followed by melphalan (n=17, 22.7%) and others (n=3, 4.0%). Among the two observational studies, the median overall survival after CRS-HIPEC treatment was 29.5-37 months. In one limited comparative effectiveness study (n=13), albeit statistically non-significant CRS-HIPEC was associated with higher progression-free survival versus CRS alone (3-year rates, 71.4% versus 0%, P=0.10). When the HIPEC regimens were compared, melphalan use was associated with decreased uLMS-related mortality compared to a cisplatin-based regimen, but the association was not statistically significant (hazard ratio 0.35, 95% confidence interval 0.04-3.05, P=0.35).

CONCLUSION

Effectiveness of CRS-HIPEC for disseminated peritoneal uLMS is yet to be determined. As interpretation of the available data on survival is limited due to small sample sizes or the lack of an active comparator, further study is warranted to examine the safety and survival effect of CRS-HIPEC in disseminated peritoneal uLMS.

Italian consensus conference on management of uterine sarcomas on behalf of S.I.G.O. (Societa' italiana di Ginecologia E Ostetricia)

BACKGROUND

Uterine sarcomas are very rare tumours with different histotypes, molecular features and clinical outcomes; therefore, it is difficult to carry out prospective clinical trials, and this often results in heterogeneous management of patients in the clinical practice.

AIM

We planned to set up an Italian consensus conference on these diseases in order to provide recommendations on treatments and quality of care in our country.

RESULTS

Early-stage uterine sarcomas are managed by hysterectomy + bilateral salpingo-oophorectomy according to menopausal status and histology; lymphadenectomy is not indicated in patients without bulky nodes, and morcellation must be avoided. The postoperative management is represented by observation, even though chemotherapy can be considered in some high-risk patients. In early-stage low-grade endometrial stromal sarcoma and adenosarcomas without sarcomatous overgrowth, hormonal adjuvant treatment can be offered based on hormone receptor expression. In selected cases, external beam radiotherapy ± brachytherapy can be considered to increase local control only. Patients with advanced disease involving the abdomen can be offered primary chemotherapy (or hormonal therapy in the case of low-grade endometrial stromal sarcoma and adenosarcoma without sarcomatous overgrowth), even if potentially resectable in the absence of residual disease in order to test the chemosensitivity (or hormonosensitivity); debulking surgery can be considered in patients with clinical and radiological response. Chemotherapy is based on anthracyclines ± ifosfamide or dacarbazine. Palliative radiotherapy can be offered for symptom control, and stereotactic radiotherapy can be used for up to five isolated metastatic lesions.

CONCLUSIONS

Treatment of uterine sarcoma should be centralised at referral centres and managed in a multidisciplinary setting.

A single-arm confirmatory trial of pazopanib in patients with paclitaxel-pretreated primary cutaneous angiosarcoma: Japan Clinical Oncology Group study (JCOG1605, JCOG-PCAS protocol)

Background

Paclitaxel is a standard of care for patients with primary cutaneous angiosarcoma of the scalp and face. However, no standard second-line treatment for paclitaxel-resistant patients has ever been established. Since primary cutaneous angiosarcoma expresses a high level of vascular endothelial growth factor receptor, the multitargeted tyrosine kinase inhibitor pazopanib seemed to be the most promising agent, and several retrospective studies have demonstrated its activity against this disease. However, the efficacy and safety of pazopanib in paclitaxel-resistant patients with primary cutaneous angiosarcoma have never been evaluated in a clinical trial.

Methods

In February 2018 the Dermatologic Oncology Group of Japan Clinical Oncology Group started a single-arm confirmatory trial to evaluate the efficacy and safety of pazopanib as a second-line treatment for patients with primary cutaneous angiosarcoma whose disease was resistant to paclitaxel or who were unable to tolerate paclitaxel (JCOG1605, JCOG-PCAS). Patients with primary cutaneous angiosarcoma not associated with lymphedema or radiation, progressing despite first-line paclitaxel monotherapy are included in the study. No prior systemic chemotherapy other than paclitaxel is permitted. Pazopanib is administered orally at an initial dosage of 800 mg once daily. Dose modifications for adverse events are made according to the dose reduction criteria described in the protocol. Treatment is continued until recurrence, disease progression, unacceptable toxic effects, patient refusal, or death. The primary endpoint is progression-free survival, secondary endpoints include overall survival, response rate, disease control rate, adverse events, and serious adverse events. We plan to recruit 30 participants in 5.5 years from 23 Japanese institutions. The follow-up period is set as 1 year after completion of accrual. The study protocol was approved by the Japan Clinical Oncology Group Protocol Review Committee in December 2017. Ethical approval for this study was granted by Ethics Committee of each institute.

Discussion

If the primary endpoint is met, pazopanib will be regarded as a standard of care for paclitaxel-resistant patients for whom no standard second-line treatment is established.

Trials registration

Registry number: UMIN000031438 [http://www.umin.ac.jp/ctr/index.htm]. Date of Registration: 23/Feb/2018. Date of First Participant Enrollment: 8/Mar/2018.

Efficacy and safety of trabectedin in metastatic uterine leiomyosarcoma: A retrospective multicenter study of the Spanish ovarian cancer research group (GEICO)

•

Trabectedin confers clinical benefit in patients with recurrent/metastatic uterine leiomyosarcoma.

•

Our data are similar to those previously reported in clinical studies.

•

Trabectedin is especially effective when administered in earlier lines.

•

Trabectedin has a manageable safety profile.

Objective

We assessed trabectedin in patients with advanced uterine leiomyosarcoma (uLMS) in real-life clinical practice given according to the marketing authorization.

Methods

Thirty-six women from 11 tertiary hospitals across Spain who received trabectedin after anthracycline-containing regimen/s were retrospectively analyzed. The primary endpoint was progression-free survival (PFS).

Results

Median PFS and overall survival (OS) since starting trabectedin treatment were 5.4 (95%CI: 3.5–7.3) and 18.5 months (95%CI: 11.5–25.6), respectively. Median OS was significantly higher (P = 0.028) in patients receiving trabectedin in ≤ 2nd line (25.3 months) than in ≥ 3rd (15.1 months) and with ECOG performance status ≤ 1 at trabectedin start (19.8 months) than ECOG 2–3 (6.0 months, P = 0.013). When calculating OS since diagnosis, patients had longer OS with localized disease at diagnosis (87.4 months) vs. locally advanced (30.0 months) or metastatic (44.0 months, P = 0.041); and patients who received adjuvant therapy (87.4 months) compared with those who did not (30.0 months, P = 0.003), especially when receiving radiochemotherapy (106.7 months, P = 0.027). One patient (2.8%) had a complete response (CR) and nine patients (25.0%) achieved a partial response (PR) for an objective response rate of 27.8% with median response duration of 11 months (range: 4–93). Eighteen patients (50.0%) had disease stabilization for a disease control rate (DCR) of 77.8%. More patients receiving trabectedin in 1st-line of advanced disease achieved CR (16.7%) and PR (50.0%) than those in ≥ 2nd line/s (0.0% and 20.0%), whereas the DCR was similar across treatment lines. Reversible neutropenia was the most common grade 3/4 laboratory abnormality (19.4%).

Conclusions

Trabectedin confers clinical benefit in patients with recurrent/metastatic uLMS, given after failure to an anthracycline-based regimen being comparable to those reported in clinical trials and with a manageable safety profile.

Different approaches to advanced soft tissue sarcomas depending on treatment line, goal of therapy and histological subtype

Introduction: Although rapid evolution over the past few years in advanced soft tissue sarcoma (STS) management has not been without its challenges, it has brought clarity in several areas.Areas covered: This article summarizes the proceedings of the third edition of the Soft Tissue Sarcoma: Evidence and Experience symposium held March 2019 in Madrid, Spain. An update is provided of current approaches to advanced STS management. Case studies illustrate the role of trabectedin in advanced STS management.Expert opinion: First-line treatment of advanced STS requires distinct therapeutic strategies depending on goal: tumor shrinkage or tumor control. Since all sarcoma patients benefit from active treatment irrespective of age or line of therapy, oncologists have a duty to offer active systemic therapies unless the patient is unfit for treatment or chooses to end active treatment. Beyond the first line, histology becomes increasingly relevant for treatment selection. Agents with activity in specific sarcoma subtypes have been identified. Rare tumors represent a substantial medical need requiring strong international collaboration between research groups, pharmaceutical companies, regulatory agencies, and patients to identify active drugs per subtype. Multidisciplinary care in an expert sarcoma center is the primary means of reducing morbidity and mortality in patients with sarcoma.

Copper ions are novel therapeutic agents for uterine leiomyosarcoma

BACKGROUND

Multidrug resistance is a major concern in uterine leiomyosarcoma treatment. Development of effective chemotherapies and management of drug resistance in patients is necessary. The copper efflux transporter adenosine triphosphatase copper transporting beta is a member of the P-type adenosine triphosphatase family and is also known as a strong platinum efflux transporter. Various reports have shown the association between adenosine triphosphatase copper transporting beta and platinum resistance; however, suitable inhibitors or methods for inhibiting platinum efflux via adenosine triphosphatase copper transporting beta are not developed.

OBJECTIVE

Our study focused on platinum resistance in uterine leiomyosarcoma. The role of adenosine triphosphatase copper transporting beta in uterine leiomyosarcoma resistance to platinum drugs was investigated both in vitro and in vivo.

STUDY DESIGN

Adenosine triphosphatase copper transporting beta expression was investigated by Western blotting and the efficacy of copper sulfate pretreatment and cisplatin administration in adenosine triphosphatase copper transporting beta-expressing cells was investigated both in vitro and in vivo.

RESULTS

Western blot analysis of SK-LMS-1 cells (uterine leiomyosarcoma cell line) revealed strong adenosine triphosphatase copper transporting beta expression. A permanent SK-LMS-ATPase copper transporting beta-suppressed cell line (SK-LMS-7B cells) was generated, and cisplatin exhibited a significant antitumor effect in SK-LMS-7B cells, both in vitro (SK-LMS-1 cells, half-maximal inhibitory concentration, 17.2 μM; SK-LMS-7B cells, half-maximal inhibitory concentration, 4.2 μM, P < .01) and in xenografts compared with that in SK-LMS-1 cells (5.8% vs 62.8%, P < .01). Copper sulfate was identified as a preferential inhibitor of platinum efflux via adenosine triphosphatase copper transporting beta. In SK-LMS-1 cells pretreated with 15 μM copper sulfate for 3 hours, the cisplatin half-maximal inhibitory concentration decreased significantly compared with that in untreated cells and resulted in significantly increased intracellular platinum accumulation (1.9 pg/cell vs 8.6 pg/cell, P < .01). The combination of copper sulfate pretreatment with cisplatin administration was also effective in vivo and caused cisplatin to exhibit significantly increased antitumor effects in mice with SK-LMS-1 xenografts (3.1% vs 62.7%, P < .01).

CONCLUSION

Our study demonstrates that adenosine triphosphatase copper transporting beta is overexpressed in uterine leiomyosarcoma cells and that copper sulfate, which acts as an inhibitor of platinum efflux via adenosine triphosphatase copper transporting beta, may be a therapeutic agent in the treatment of uterine leiomyosarcoma.

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.

Current status of the adjuvant therapy in uterine sarcoma: A literature review

Uterine sarcomas (US) are rare mesenchymal tumours accounting approximately for 3%–7% of all uterine cancers. Histologically, US are classified into mesenchymal tumours or mixed epithelial and mesenchymal tumours. The group of mesenchymal tumours includes uterine leiomyosarcoma (uLMS, 65% of cases), endometrial stromal sarcoma (ESS, 21%) – traditionally divided into low grade (LG-ESS) and high grade–undifferentiated uterine sarcoma (5%) and other rare subtypes such as alveolar or embryonal rhabdomyosarcoma. Despite the fact that several drugs demonstrated clinical activity in advanced or metastatic settings, the role of postoperative therapy in US remains controversial. In this review, we have summarised the current state of the art, including the chief trials on adjuvant treatment modalities in US, especially focusing on uLMS, LG-ESS and other rare histotypes.

Uterine sarcomas

Uterine sarcomas comprise a small percentage of uterine malignancies. The most common uterine sarcoma is leiomyosarcoma (LMS). Early stage uterine LMS is curable with complete hysterectomy with removal of an intact uterus. Patients with metastatic disease may achieve tumor responses with improvements in quality of life, but long-term remissions are rare. In this review article, I outline adjuvant therapies for early stage resected uterine LMS, as well as treatment of metastatic disease.

A patient-derived orthotopic xenograft (PDOX) nude-mouse model precisely identifies effective and ineffective therapies for recurrent leiomyosarcoma

Leiomyosarcoma is a rare and recalcitrant disease. Doxorubicin (DOX) is usually considered first-line treatment for this disease, but frequently is ineffective. In order to individualize therapy for this and other cancers, we have developed the patient-derived orthotopic xenograft (PDOX) mouse model. In the present study, we implanted a recurrent leiomyosarcoma from a resected tumor from the patient's thigh into the femoral muscle of nude mice. The following drugs were tested on the leiomyosarcoma PDOX model: DOX, the combination of gemcitabine (GEM) and docetaxel (DOC), trabectedin (TRA), temozolomide (TEM), pazopanib (PAZ) and olaratumab (OLA). Of these agents GEM/DOC, TRA and TEM were highly effective in the leiomyosarcoma PDOX model, the other agents, including first-line therapy DOX, were ineffective. Thus the leiomyosarcoma PDOX model could precisely distinguish effective and ineffective drugs, demonstrating the potential of the PDOX model for leiomyosarcoma treatment.

Adjuvant Gemcitabine Plus Docetaxel Followed by Doxorubicin Versus Observation for High-Grade Uterine Leiomyosarcoma: A Phase III NRG Oncology/Gynecologic Oncology Group Study

PURPOSE

We conducted a randomized phase III trial to determine whether adjuvant chemotherapy improves survival in women with uterine leiomyosarcoma.

METHODS

Women with uterus-confined, high-grade leiomyosarcoma who were confirmed disease free by imaging were randomly assigned to four cycles of gemcitabine plus docetaxel, followed by four cycles of doxorubicin, or to observation. All were followed for evidence of recurrence. The primary end point was overall survival (OS).

RESULTS

With international collaboration, 38 of the targeted accrual of 216 patients were enrolled, after which the study was closed by the National Cancer Institute for accrual futility. Twenty patients were assigned to chemotherapy, 18 to observation. Among the 17 patients treated with at least one cycle of chemotherapy, grade 3 or 4 toxicities were observed in 47%; among the 18 patients assigned to observation, one had grade 3 hypertension. There were six deaths (chemotherapy, n = 5; observation, n = 1), all due to disease. The restricted mean survival time for OS was estimated as 34.3 months (95% CI, 25.3 to 43.3 months) in the chemotherapy arm and as 46.4 months (95% CI, 43.6 to 49.1 months) in the observation arm. There were eight recurrences in each arm. The restricted mean survival time for recurrence-free survival was estimated as 18.1 (95% CI, 14.2 to 22.0) months in the chemotherapy arm and as 14.6 months (95% CI, 10.3 to 19.0 months) in the observation arm. Neither survival outcome comparison was considered statistically robust, due to the small sample size.

CONCLUSION

Despite international collaboration to test the role of adjuvant chemotherapy in uterine-confined leiomyosarcoma, this study was closed for accrual futility. Although the sample size precludes robust statistical comparison, observed OS and recurrence-free survival data do not show superior outcomes with adjuvant chemotherapy.

Systemic Treatment of Metastatic/Recurrent Uterine Leiomyosarcoma: A Changing Paradigm

The treatment of metastatic and recurrent uterine leoimyosarcoma (uLMS) has evolved rapidly in the past several years. Leoimyosarcoma is extremely aggressive and responds poorly to traditional chemotherapeutics. Recent regulatory approval of novel treatment options has significantly expanded the therapeutic armamentarium, and the addition of these therapies has challenged clinicians to select and optimally sequence these new compounds. Additionally, the potential role of immunotherapy is being assessed in current uLMS clinical trials. Given the increasing number of agents available both in the U.S. and globally, a treatment template that addresses optimal sequencing based upon expert consensus would be useful. Current guidelines, although listing various options, lack granularity by line of therapy. Most patients with leiomyosarcoma, even in early stage, are treated with surgery followed by adjuvant chemotherapy despite uLMS being relatively chemoresistant. Adjuvant chemotherapy often includes the combination of gemcitabine and docetaxel with or without doxorubicin in first-line systemic therapy, but these cytotoxic agents only provide patients with advanced disease a 5-year survival <30%. This review will focus on examination of current guidelines and consensus building for optimal sequencing of systemic therapies for advanced or recurrent uLMS. Critical ongoing studies investigating novel approaches including immunotherapeutics and genetic alterations also will be discussed. IMPLICATIONS FOR PRACTICE: Recent regulatory approval of novel treatment options has significantly expanded the therapeutic armamentarium, and the addition of these therapies has challenged clinicians to select and optimally sequence these compounds. This review will focus on examination of current guidelines and consensus building for optimal sequencing of systemic therapies for advanced or recurrent uterine leoimyosarcoma.

Trabectedin arrests a doxorubicin-resistant PDGFRA-activated liposarcoma patient-derived orthotopic xenograft (PDOX) nude mouse model

BACKGROUND

Pleomorphic liposarcoma (PLPS) is a rare, heterogeneous and an aggressive variant of liposarcoma. Therefore, individualized therapy is urgently needed. Our recent reports suggest that trabectedin (TRAB) is effective against several patient-derived orthotopic xenograft (PDOX) mouse models. Here, we compared the efficacy of first-line therapy, doxorubicin (DOX), and TRAB in a platelet-derived growth factor receptor-α (PDGFRA)-amplified PLPS.

METHODS

We used a fresh sample of PLPS tumor derived from a 68-year-old male patient diagnosed with a recurrent PLPS. Subcutaneous implantation of tumor tissue was performed in a nude mouse. After three weeks of implantation, tumor tissues were isolated and cut into small pieces. To match the patient a PDGFRA-amplified PLPS PDOX was created in the biceps femoris of nude mice. Mice were randomized into three groups: Group 1 (G1), control (untreated); Group 2 (G2), DOX-treated; Group 3 (G3), TRAB-treated. Measurement was done twice a week for tumor width, length, and mouse body weight.

RESULTS

The PLPS PDOX showed resistance towards DOX. However, TRAB could arrest the PLPS (p < 0.05 compared to control; p < 0.05 compared to DOX) without any significant changes in body-weight.

CONCLUSIONS

The data presented here suggest that for the individual patient the PLPS PDOX model could specifically distinguish both effective and ineffective drugs. This is especially crucial for PLPS because effective first-line therapy is harder to establish if it is not individualized.

A phase II randomised (calibrated design) study on the activity of the single-agent trabectedin in metastatic or locally relapsed uterine leiomyosarcoma

Background

Patients with recurrent/metastatic uterine leiomyosarcoma (U-LMS) have a dismal prognosis. This phase II study aims to evaluate trabectedin efficacy and safety in advanced U-LMS.

Methods

Eligible patients had received ≥ one line of chemotherapy. Gemcitabine ± docetaxel naive patients were randomised to Arm A: trabectedin 1.3 mg/m² or calibration Arm B: gemcitabine 900 mg/m² and docetaxel 75 mg/m². Patients who had already received gemcitabine ± docetaxel directly entered Arm A. Primary end-point: 6-month progression-free rate (PFS-6). The null hypothesis that the true PFS-6 = 14% was tested against a one-sided alternative. This design yielded a 5% type I error rate and 90% power when the true PFS-6 is 25%.

Results

Overall, 126 patients entered Arm A (45 from randomisation and 81 directly) and 42 Arm B. Arm A patients characteristics: median age = 57; ≥2 previous chemotherapy lines = 37.4%; metastatic disease = 93%. The study met the condition for trabectedin activity: PFS-6 = 35.2% (95% CI: 26.2–45). No difference in PFS by the number of previous chemotherapy lines emerged. Median OS = 20.6 months (IQR: 8–36.4). In Arm B, the PFS-6 = 51.5% (95% CI: 33.5–69.2). No toxic deaths occurred. In Arm A, only 4 patients interrupted treatment for toxicity.

Conclusions

Trabectedin is active and well tolerated, retaining similar efficacy across one to three previous lines of chemotherapy.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in seven patients with peritoneal sarcomatosis from uterine sarcoma

Peritoneal sarcomatosis from uterine sarcoma is a rare disease with no effective treatment and poor prognosis. Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has successful results in peritoneal carcinomatosis from gastrointestinal/gynecological origins. We show that CRS/HIPEC is safe, feasible, and may benefit selected patients with peritoneal sarcomatosis from uterine sarcoma.

Long-Lasting Response to Trabectedin in a Patient with Metastatic Uterine Leiomyosarcoma: A Case Report

Background

Uterine leiomyosarcoma (uLMS) is a rare tumor that accounts for 1% of all uterine malignancies. In spite of adequate surgical resection of uLMS, even in the early stage, patients remain at high risk for local and distant recurrence. Therefore, the treatment of advanced uLMS represents a considerable challenge.

Methods

We report the case of a 47-year-old woman who presented with uLMS with abnormal vaginal bleeding.

Results

The patient underwent a total hysterectomy and bilateral adnexectomy, which was followed by 1 year progression-free survival without adjuvant therapy. Thereafter, new lung metastases and local progression at the vaginal stump were observed. Chemotherapy with ifosfamide and doxorubicin was administered. However, after 4 cycles, a CT scan revealed disease progression in the lung metastases. Subsequently, the patient was treated with trabectedin at a dose of 1.5 mg/m² for 6 cycles resulting in complete remission of the lung metastases as well as partial remission of the mass in the vaginal stump after 9 cycles of trabectedin. The patient is currently on maintenance therapy with trabectedin and has no recurrence.

Conclusion

Trabectedin seems to be an efficient option for patients with uLMS as demonstrated by a long-lasting response in a pretreated patient with an acceptable safety profile with no signs of cumulative toxicity.

Soft Tissue and Uterine Leiomyosarcoma

Leiomyosarcoma (LMS) is one of the most common subtypes of soft tissue sarcoma in adults and can occur in almost any part of the body. Uterine leiomyosarcoma is the most common subtype of uterine sarcoma. Increased awareness of this unique histology has allowed for the development of drugs that are specific to LMS and has begun to shed light on the similarities and possible unique aspects of soft tissue and uterine LMS. In this review, we summarize the current understanding of the epidemiology, diagnosis, genomics, and treatment options for LMS.

Systemic treatment in adult uterine sarcomas

Uterine sarcomas (US) are rare mesenchymal tumours of the uterus and are divided mainly into uterine leiomyosarcoma (uLMS), low grade endometrial stromal sarcoma (LG-ESS), high grade endometrial stromal sarcoma (HG-ESS), adenosarcomas and high grade undifferentiated sarcoma (HGUS). US are often high-grade tumours with a high local recurrence rate and metastatic risk. We here discuss the current standard of care and knowledge of systemic therapy for adult uterine sarcomas, in particular uLMS, LG-ESS, HG-ESS and HGUS, in both the adjuvant as well as the metastatic setting.