Trabectedin Plus Radiotherapy for Advanced Soft-Tissue Sarcoma: Experience in Forty Patients Treated at a Sarcoma Reference Center

HMGA1 regulates trabectedin sensitivity in advanced soft-tissue sarcoma (STS): A Spanish Group for Research on Sarcomas (GEIS) study

HMGA1 is a structural epigenetic chromatin factor that has been associated with tumor progression and drug resistance. Here, we reported the prognostic/predictive value of HMGA1 for trabectedin in advanced soft-tissue sarcoma (STS) and the effect of inhibiting HMGA1 or the mTOR downstream pathway in trabectedin activity. The prognostic/predictive value of HMGA1 expression was assessed in a cohort of 301 STS patients at mRNA (n = 133) and protein level (n = 272), by HTG EdgeSeq transcriptomics and immunohistochemistry, respectively. The effect of HMGA1 silencing on trabectedin activity and gene expression profiling was measured in leiomyosarcoma cells. The effect of combining mTOR inhibitors with trabectedin was assessed on cell viability in vitro studies, whereas in vivo studies tested the activity of this combination. HMGA1 mRNA and protein expression were significantly associated with worse progression-free survival of trabectedin and worse overall survival in STS. HMGA1 silencing sensitized leiomyosarcoma cells for trabectedin treatment, reducing the spheroid area and increasing cell death. The downregulation of HGMA1 significantly decreased the enrichment of some specific gene sets, including the PI3K/AKT/mTOR pathway. The inhibition of mTOR, sensitized leiomyosarcoma cultures for trabectedin treatment, increasing cell death. In in vivo studies, the combination of rapamycin with trabectedin downregulated HMGA1 expression and stabilized tumor growth of 3-methylcholantrene-induced sarcoma-like models. HMGA1 is an adverse prognostic factor for trabectedin treatment in advanced STS. HMGA1 silencing increases trabectedin efficacy, in part by modulating the mTOR signaling pathway. Trabectedin plus mTOR inhibitors are active in preclinical models of sarcoma, downregulating HMGA1 expression levels and stabilizing tumor growth.

Trabectedin and low-dose radiation therapy in patients with advanced leiomyosarcoma

Background and objectives

Dimensional response is an unmet need in second lines of advanced soft tissue sarcomas (STS). Indeed, the three approved drugs, pazopanib, trabectedin, and eribulin, achieved an overall response rate (ORR) of less than 10%. This fact potentially hinders the options for fast symptomatic relief or surgical rescue. The combination of trabectedin plus low-dose radiation therapy (T-XRT) demonstrated a response rate of 60% in phase I/II trial, while real-life data achieved 32.5% ORR, probably due to a more relaxed timing between treatments. These results were obtained in progressing and advanced STS. In this study, the merged databases (trial plus real life) have been analyzed, with a special focus on leiomyosarcoma patients.

Design and methods

As responses were seen in a wide range of sarcoma histologies (11), this study planned to analyze whether leiomyosarcoma, the largest subtype with 26 cases (30.6%) in this series, exhibited a better clinical outcome with this therapeutic strategy. In addition, four advanced and progressing leiomyosarcoma patients, all with extraordinarily long progression-free survival of over 18 months, were collected.

Results

A total of 847 cycles of trabectedin were administered to 85 patients, with the median number of cycles per patient being 7 (1-45+). A trend toward a longer progression-free survival (PFS) was observed in leiomyosarcoma patients with median PFS (mPFS) of 9.9 months [95% confidence interval (CI): 1.1-18.7] versus 5.6 months (95% CI: 3.2-7.9) for the remaining histologies, p = 0.25. When leiomyosarcoma and liposarcoma were grouped, this difference reached statistical significance, probably due to the special sensitivity of myxoid liposarcoma. The mPFS for L-sarcomas was 12.7 months (95% CI: 7-18.5) versus 4.3 months (95% CI: 3.3-5.3) for the remaining histologies, p = 0.001. Cases with long-lasting disease control are detected among leiomyosarcoma patients.

Conclusion

Even when extraordinarily long-lasting responses do exist among leiomyosarcoma patients treated with T-XR, we were unable to demonstrate a significant difference favoring leiomyosarcoma patients in clinical outcomes.

Objective Responses in Metastatic Pleomorphic Rhabdomyosarcoma Treated with Combination of Doxorubicin and Pembrolizumab: A Case Series

Introduction

Pleomorphic rhabdomyosarcoma is a rare subtype of rhabdomyosarcoma, a soft tissue sarcoma with skeletal muscle differentiation. Although rhabdomyosarcoma is typically seen in the pediatric population, the pleomorphic variant most frequently presents in adulthood and is characteristically aggressive with no currently established treatment regimen in the setting of metastatic disease. There has been growing interest in the application of immune checkpoint inhibitors alongside conventional chemotherapeutic agents in the treatment of pleomorphic rhabdomyosarcoma.

Case Presentation

In the present case series, we report 2 patients with metastatic pleomorphic rhabdomyosarcoma treated with combination doxorubicin and pembrolizumab who had confirmed objective responses. Of note, these 2 patients had variable PD-L1 status - negative and low positive. Duration of treatment response was notable at 14 months and 9 months, respectively, with the first patient remaining on maintenance pembrolizumab therapy and the second patient subsequently achieving complete response with third-line trabectedin. Both patients are currently undergoing routine interval imaging with no evidence of disease at this time.

Conclusion

This report highlights and discusses the potential role of PD-1 blockade in the treatment of pleomorphic rhabdomyosarcoma and also discusses burgeoning immunological data that may explain the clinical responses seen in these 2 cases.

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.

Optimal Prognostic Factors for Metastatic and Inoperable Sarcomas Treated With Pazopanib, Eribulin, and Trabectedin

BACKGROUND/AIM

The prognosis of metastatic and inoperable sarcomas is extremely poor, and intensive chemotherapy-based treatment is typically administered to prolong survival. Currently, pazopanib, eribulin, and trabectedin are key drugs used in patients with these sarcomas. The aim of the study was to identify prognostic factors for metastatic and inoperable bone and soft tissue sarcomas.

PATIENTS AND METHODS

Clinicopathological data of 46 patients with metastatic and inoperable sarcomas treated with pazopanib, eribulin, and trabectedin between January 2013 and February 2022 at our institution were retrospectively analyzed. Age, sex, primary tumor location, adverse effects, history of doxorubicin and radiation therapy, performance status scores, maximum tumor response, and survival duration were evaluated. The significant prognostic factors were identified using Cox proportional hazards models. Moreover, the 5-year survival rate was evaluated using the Kaplan-Meier method.

RESULTS

The median survival duration after treatment was 13.3 months, where the 5-year overall survival rate was estimated to be 9.85%. Both univariate and multivariate analyses revealed significant relationships among patient prognosis, performance status, and tumor response.

CONCLUSION

Performance status scores and tumor response were significantly associated with patient prognosis. Therefore, regardless of age, sex, primary tumor location, adverse effects, and history of doxorubicin and radiation therapy, use of cutting-edge drugs, such as pazopanib, eribulin, and trabectedin, may be advantageous in patients with advanced sarcomas, if their drug response and performance status scores are good.

Local Therapies for Metastatic Sarcoma: Why, When, and How?

Management of patients with advanced sarcoma has been evolving in recent decades, from a one-fit-all perspective to a more refined, personalized, and multidisciplinary approach. In parallel, the evolution of local therapies (radiotherapy, surgical and interventional radiology techniques) has contributed to the improvement of survival of patients with advanced sarcoma. In this article, we review the evidence regarding local treatments in advanced sarcoma, as well as its integration with systemic therapies, to provide the reader a wider and deeper perspective on the management of patients with metastatic sarcoma.

Experience with second-line trabectedin in daily clinical practice: case studies

As a recommended second-line option for advanced soft tissue sarcoma, trabectedin can provide the necessary balance between long-term tumor control and preserved quality of life. Three case studies illustrate the long-lasting responses that patients can achieve with second-line trabectedin. A female patient with metastatic leiomyosarcoma maintained disease control for 2 years with trabectedin (× 41 cycles) with excellent tolerability and no relevant adverse events. At the time of writing, a male patient with a metastatic solitary fibrous tumor was asymptomatic after 30 cycles of trabectedin and treatment was ongoing. A young male patient with a recurrent, nonresectable, retroperitoneal myxoid/round cell liposarcoma was able to continue his sporting activities (triathlons) over 2 years with trabectedin (× 14 cycles) plus watchful waiting.

A Multicenter, Prospective, Observational Study to Assess the Clinical Activity and Impact on Symptom Burden and Patients' Quality of Life in Patients with Advanced Soft Tissue Sarcomas Treated with Trabectedin in a Real-World Setting in Greece

This non-interventional, multicenter, prospective study aimed to evaluate the real-world activity of trabectedin, and its impact on symptom burden and quality of life in patients with advanced soft tissue sarcoma (aSTS) treated in routine clinical settings in Greece. Patients with histologically confirmed aSTS newly initiated on trabectedin were enrolled. The primary endpoint was progression-free survival (PFS) rate at 6 months. Secondary endpoints included PFS rate at 3 months, median PFS, objective response rate (ORR), disease control rate (DCR), overall survival (OS), and an assessment of the impact of treatment on health-related quality of life (HRQoL), cancer-related symptom burden and symptom interference with function, as well as all-cause treatment discontinuation rate. A total of 64 eligible patients from 13 Greek centers were evaluated. Patients received a median of three trabectedin cycles per patient (interquartile range [IQR]: 2.0-6.0). Median PFS was 6.6 months with 67.9% and 51.2% of patients free from progression at 3 and 6 months, respectively. ORR was 7.8% and DCR 21.9%. Median OS was 13.1 months. No significant changes from enrolment were noted in HRQoL scores. In total, 30 patients (46.9%) had at least one trabectedin-related adverse drug reaction (ADR) and 9 (14.1%) at least one serious ADR. The treatment discontinuation rate due to toxicity was 9.4%. These results suggest that trabectedin is an active treatment with clinically meaningful benefits in patients with aSTS with no new safety signals.

Risk factors for the development of local recurrence in extremity soft-tissue sarcoma

INTRODUCTION

Local recurrence (LR) is one of the main pitfalls in surgery for extremities soft tissue sarcoma (eSTS). Achieving clear histopathological margins is the most important factor to reduce the risk of LR, but the ability to do so depends on not only surgical technique but also the interplay between tumor biology, anatomical location and surgical approach. The balance between postoperative morbidity and oncological benefits in reducing the risk of LR needs to be considered.

AREAS COVERED

This review will cover which etiological factors for the development of eSTS lead to an increased risk of LR and discuss histological subtypes that have a high risk of LR and which surgical and neoadjuvant therapeutic strategies can minimize the risk of LR.

EXPERT OPINION

The traditional view that surgical radicality always results in low rates of LR, while marginality alone always leads to high rates of relapse, is outdated. In the modern era of surgical oncology, limb salvage and high-level function after resectional surgery are the key surgical goals. The best results are achieved by combining effective neoadjuvant treatments with planned bespoke oncological operations that consider the biological and anatomical factors of each individual sarcoma.

Targeted and immuno-based therapies in sarcoma: mechanisms and advances in clinical trials

Sarcomas represent a distinct group of rare malignant tumors with high heterogeneity. Limited options with clinical efficacy for the metastatic or local advanced sarcoma existed despite standard therapy. Recently, targeted therapy according to the molecular and genetic phenotype of individual sarcoma is a promising option. Among these drugs, anti-angiogenesis therapy achieved favorable efficacy in sarcomas. Inhibitors targeting cyclin-dependent kinase 4/6, poly-ADP-ribose polymerase, insulin-like growth factor-1 receptor, mTOR, NTRK, metabolisms, and epigenetic drugs are under clinical evaluation for sarcomas bearing the corresponding signals. Immunotherapy represents a promising and favorable method in advanced solid tumors. However, most sarcomas are immune "cold" tumors, with only alveolar soft part sarcoma and undifferentiated pleomorphic sarcoma respond to immune checkpoint inhibitors. Cellular therapies with TCR-engineered T cells, chimeric antigen receptor T cells, tumor infiltrating lymphocytes, and nature killer cells transfer show therapeutic potential. Identifying tumor-specific antigens and exploring immune modulation factors arguing the efficacy of these immunotherapies are the current challenges. This review focuses on the mechanisms, advances, and potential strategies of targeted and immune-based therapies in sarcomas.

What is the standard indication of adjuvant or neoadjuvant chemotherapy in localized soft-tissue sarcoma?

PURPOSE OF REVIEW

The aim is to bring latest evidence of the role of perioperative chemotherapy in localized soft-tissue sarcomas (STS) of limbs and to review the risk classification systems of retroperitoneal and extremity STS.

RECENT FINDINGS

High-risk subset of localized STS of limbs and trunk-wall, defined with classic prognostic factors, consistently obtained 5-year overall survival ranging from 69 to 76% in randomized patients treated with full-dose of anthracycline and ifosfamide. Validated nomograms accurately predict, on individual basis, the risk of death and recurrence in localized STS of retroperitoneum and limbs, enabling a better selection of high-risk patients (usually those with death risk of ≥40%) that potentially could benefit with perioperative systemic treatment. Nomograms have virtually converted a negative large perioperative trial into a positive, favouring chemotherapy arm in the high-risk selection.

SUMMARY

Perioperative three cycles of full-dose of anthracycline and ifosfamide should be proposed on an individual basis, in reference sarcoma centres, to high-risk localized STS of limbs or trunk-wall in certain histologies.

The Role of Macrophages in Cancer Development and Therapy

Macrophages are critical mediators of tissue homeostasis and influence various aspects of immunity. Tumor-associated macrophages are one of the main cellular components of the tumor microenvironment. Depending on their activation status, macrophages can exert a dual influence on tumorigenesis by either antagonizing the cytotoxic activity of immune cells or, less frequently, by enhancing antitumor responses. In most situations, TAMs suppress T cell recruitment and function or regulate other aspects of tumor immunity. The importance of TAMs targeting in cancer therapy is derived from the strong association between the high infiltration of TAMs in the tumor tissue with poor patient prognosis. Several macrophage-targeting approaches in anticancer therapy are developed, including TAM depletion, inhibition of new TAM differentiation, or re-education of TAM activation for cancer cell phagocytosis. In this review, we will describe the role of TAMs in tumor development, including such aspects as protumorigenic inflammation, immune suppression, neoangiogenesis, and enhancement of tissue invasion and distant metastasis. Furthermore, we will discuss therapeutic approaches that aim to deplete TAMs or, on the contrary, re-educate TAMs for cancer cell phagocytosis and antitumor immunity.