Clinical features and outcomes of young patients with epithelioid sarcoma: an analysis from the Children's Oncology Group and the European paediatric soft tissue Sarcoma Study Group prospective clinical trials

Lymph Node Staging and Treatment in Pediatric Patients With Soft Tissue Sarcomas: A Consensus Opinion From the Children's Oncology Group, European paediatric Soft Tissue Sarcoma Study Group, and the Cooperative Weichteilsarkom Studiengruppe

Accurate staging of nodal involvement in pediatric sarcoma patients is important to determine correct systemic and local therapy, with the goal to reduce subsequent recurrences. However, differences in lymph node staging strategies, definitions, and treatment protocols between the Children's Oncology Group (COG), European paediatric Soft tissue sarcoma Study Group (EpSSG), and the Cooperative Weichteilsarkom Studiengruppe (CWS) complicate comparisons. In this article, we aim to establish internationally recognized recommendations for lymph node assessment and treatment of children and adolescents diagnosed with rhabdomyosarcoma (RMS) and non-rhabdomyosarcoma soft tissue sarcoma (NRSTS) according to the Consensus Conference Standard Operating Procedure methodology.

The efficacy and safety of vincristine, irinotecan and anlotinib in Epithelioid Sarcoma

BACKGROUND

Epithelioid sarcoma is a rare soft tissue sarcoma characterized by SMARCB1/INI1 deficiency. Much attention has been paid to the selective EZH2 inhibitor tazemetostat, where other systemic treatments are generally ignored. To explore alternative treatment options, we studied the effects of irinotecan-based chemotherapy in a series of epithelioid sarcoma patients.

METHODS

We retrospectively reviewed data from patients with metastatic or unresectable epithelioid sarcoma at the Peking University People's Hospital treated with irinotecan (50 mg/m2/d d1-5 Q3W) in combination with Anlotinib (12 mg Qd, 2 weeks on and 1 week off) from July 2015 to November 2021.

RESULTS

A total of 54 courses were administered. With a median follow up of 21.2 months (95% CI, 12.2, 68.1), the 5-year overall survival rate was 83.3%. Five of eight (62.5%) patients presented with unresectable localized lesions, including local tumor thrombosis and lymphatic metastasis. The other patients had unresectable pulmonary metastases. Six of eight (75%) patients had progressed following two lines of systemic therapy. The objective response rate reached 37.5% (three of eight patients) while stabilized disease was observed in 62.5% (five of eight) of patients. No patient had progressed at initial evaluation. At the last follow up, two patients were still using the combination and three patients had ceased the therapy due to toxicities such as diarrhea, nausea, and emesis. One patient changed to tazemetostat for maintenance and one patient stopped treatment due to coronavirus disease 2019 (COVID-19). Another patient stopped therapy as residual lesions had been radiated.

CONCLUSIONS

The combination of irinotecan and Anlotinib as a salvage regimen may be considered another effective treatment option for refractory epithelioid sarcoma.

TRIAL REGISTRATION

This study was approved in the Medical Ethics Committee of Peking University People's Hospital on October 28, 2022 (No.: 2022PHD015-002). The study was registered in Clinicaltrials.gov with identifier no. NCT05656222.

The significance of margins in pediatric Non-Rhabdomyosarcoma soft tissue sarcomas: Consensus on surgical margin definition harmonization from the INternational Soft Tissue SaRcoma ConsorTium (INSTRuCT)

BACKGROUND

Margin status following surgery in children, adolescents, and young adults with soft tissue sarcomas is controversial and has been defined differently by various specialties, with definitions changing over time and by cooperative group. The International Soft Tissue Sarcoma Consortium (INSTRuCT) is a collaboration of the Children's Oncology Group (COG) Soft Tissue Sarcoma Committee, European pediatric Soft Tissue sarcoma Study Group (EpSSG), and the European Cooperative Weichteilsarkom Studiengruppe (CWS) devoted to improving patient outcomes by pooling and mining cooperative group clinical trial data.

METHODS

The INSTRuCT non-rhabdomyosarcoma soft tissue sarcoma (NRSTS) working group aimed to develop international harmonized recommendations regarding surgical margin assessment and definitions in children and adolescents with soft tissue tumors.

RESULTS AND CONCLUSION

This review addresses accepted principles and areas of controversy, including the perspectives of surgeons, pathologists, radiation oncologists, and pediatric oncologists, to develop a framework for building common guidelines for future research.

Lymph node metastases in paediatric and young adult patients with non-rhabdomyosarcoma soft tissue sarcoma (NRSTS): Findings from Children's Oncology Group (COG) study ARST0332

PURPOSE

The aim of this paper is to better define the clinical features and outcomes of young patients with non-rhabdomyosarcoma soft tissue sarcoma (NRSTS) with regional and distant lymph node (LN) metastases treated in a standardised fashion, we analysed LN involvement in COG study ARST0332, which evaluated a risk-based treatment strategy for young patients with all stages of NRSTS.

PATIENTS AND METHODS

Patients <30 years old with newly diagnosed NRSTS and LN metastases enrolled on ARST0332 were studied. Regional LN sampling was required for those with epithelioid sarcoma, clear cell sarcoma or clinically/radiographically enlarged LNs. Tumour features and extent of pre-enrolment resection determined treatment, including chemotherapy, radiotherapy, and delayed surgery. Recommendations for LN metastases included LN dissection at the time of primary tumour resection and dose-adapted radiotherapy based on extent of LN resection.

RESULTS

Twenty of 529 eligible and evaluable ARST0332 patients with NRSTS had LN metastases; epithelioid sarcoma had the highest incidence (18%, 5 of 28). Pre-treatment imaging identified LN enlargement in 19 of 20 patients; 1 had no pre-treatment LN imaging. At 6.9 years median follow-up for surviving patients, 5-year overall survival was 85.7% (95% CI: 33.4%, 97.9%) for seven patients with isolated LN metastases and 15.4% (95% CI: 2.5%, 38.8%) for 13 patients with additional extranodal metastases. LN recurrence occurred in only one patient without LNs sampled at initial diagnosis.

CONCLUSION

LN metastases occur in about 4% of paediatric/young adult NRSTS, are limited to a few histologic subtypes, and are rare in patients who did not have clinical or imaging evidence of lymphadenopathy, suggesting that biopsies of non-enlarged LNs are not necessary to identify occult involvement. Patients with isolated LN metastases have high 5-year overall survival (∼85%) and should be treated with curative intent.

CLINICALTRIALS

GOV REGISTRY NO

NCT00346164.

Pediatric Non-Rhabdomyosarcoma Soft Tissue Sarcomas: Standard of Care and Treatment Recommendations from the European Paediatric Soft Tissue Sarcoma Study Group (EpSSG)

This paper describes the standard of care for patients with non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) and the therapeutic recommendations developed by the European paediatric Soft tissue sarcoma Study Group (EpSSG). NRSTS form a very mixed group of mesenchymal extraskeletal malignancies. Their rarity, heterogeneity, and aggressiveness make the management of children and adolescents with these tumors complex and challenging. The overall cure rate for patients with NRSTS is around 70%, but survival depends on several prognostic variables, such as histotype and tumor grade, extent of disease and stage, tumor size, and tumor site. While surgery remains the mainstay of treatment for most of these tumors, a multimodal therapeutic approach including radiotherapy and chemotherapy is required in many cases. The EpSSG NRSTS 2005 study was the first prospective protocol tailored specifically to NRSTS. Together with the ARST0332 study developed by the North-American Soft Tissue Sarcoma Committee of the Children's Oncology Group (COG), the EpSSG NRSTS 2005 study currently represents the benchmark for these tumors, establishing risk-adapted standards of care. The EpSSG has developed common treatment recommendations for the large group of adult-type NRSTS (including synovial sarcoma), and specific treatment recommendations for other particular adult-type histologies (ie, alveolar soft-part sarcoma, clear cell sarcoma and dermatofibrosarcoma protuberans); other highly malignant tumors with a biology and clinical behavior differing from those of adult-type NRSTS (ie, rhabdoid tumors and desmoplastic small round cell tumor); and soft tissue tumors of intermediate malignancy (ie desmoid-type fibromatosis, inflammatory myofibroblastic tumors, and infantile fibrosarcoma). New effective drugs are needed for patients whose NRSTS carries the worst prognosis, ie, those with unresectable tumors, metastases at diagnosis, or relapsing disease. Progress in this area relies on our ability to develop international integrated prospective collaborations, both within existing pediatric oncology networks and, importantly, between the communities of specialists treating pediatric and adult sarcoma.

Malignant Superficial Mesenchymal Tumors in Children

Malignant superficial mesenchymal tumors are a very diverse group of neoplasms with few clinical and radiological discriminatory factors. Hence, some of these cancers are rarely suspected based on clinical and radiological grounds, others may be easily misdiagnosed, and the histological analysis of a biopsy or resection is central in the diagnostic process. In children, the age at presentation is a major element of the differential diagnosis. Some tumors have a very distinct epidemiology, while others may be seen at any age. More recently, the advances in molecular biology have greatly improved the diagnosis of mesenchymal tumors and new entities are still being described. In the present review, we provide an overview of the diversity of malignant superficial mesenchymal tumors in children, including new and/or rare entities. We discuss the important diagnostic features, be they clinical, histological, or molecular. Special attention was given to the genetic features of these tumors, particularly when they were helpful for the diagnosis or treatment.

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.

Treatment Concepts and Challenges in Nonrhabdomyosarcoma Soft Tissue Sarcomas

Pediatric nonrhabdomyosarcoma soft tissue sarcomas (NRSTSs) encompass a heterogeneous group of mesenchymal tumors with more than 50 histologic variants. The incidence of NRSTS is greater than rhabdomyosarcoma; however, each histologic type is rare. The treatment schema for all NRSTSs is largely surgical. The treatment is a risk-adapted approach based on tumor size, localization, tumor grade, and presence of metastases. Low-grade tumors are mainly managed by surgery alone, whereas for high-grade tumors a multimodal treatment concept is necessary. The multimodal treatment consists of tumor biopsy, chemotherapy, local treatment (surgery ± radiotherapy), and immunotherapy in selected conditions.

Management of sarcomas in children, adolescents and adults: Interactions in two different age groups under the umbrellas of GSF-GETO and SFCE, with the support of the NETSARC+ network

Sarcomas are a rare heterogeneous group of malignant neoplasms that can arise in almost any anatomic site and any age. Close collaboration among adult and pediatric cancer specialists in the management of these tumors is of foremost importance. In this review, we present the current multidisciplinary organization in care of patients with sarcoma in France and we review the main advances made in the last decades in systemic and radiotherapy treatment in the main sarcoma types diagnosed in children, adolescents and young adults (AYA), thanks to the international collaboration.

Early clinical and metabolic response to tazemetostat in advanced relapsed INI1 negative epithelioid sarcoma

Epithelioid sarcoma (ES) is a rare soft tissue sarcoma with an incidence of 0.05 per 100,000 population in the USA. It is characterized by multiple local recurrences and regional lymph nodes form the commonest site of metastases. The function of Integrase Inhibitor 1 (INI1) protein is lost in more than 90% of cases, which was the basis for the introduction of tazemetostat into the therapeutic armamentarium for management of advanced ES. The efficacy and manageable toxicity profile of tazemetostat have been demonstrated recently, leading to its accelerated approval for treatment of advanced ES. We report one of the first real-world cases of relapsed, metastatic ES treated with tazemetostat. The patient attained partial response with the therapy and is tolerating the drug well without serious toxicities.

An Extremely Rare Epithelioid Sarcoma Arising from the Infratemporal Fossa: A Case Report and Literature Review

INTRODUCTION

Epithelioid sarcoma (ES) is a rare histopathological type of soft tissue sarcoma. They are subcutaneous soft tissue masses that tend to arise in extremity sites (the classic type, formerly referred to as distal type) or proximal midline region of the body (the proximal type), such as the perineum, genital tract, and pelvis. The head and neck regions are rarely affected by ES, but the infratemporal fossa (ITF) is extremely rare. ES involving the ITF has not been reported before in literature. In this paper, the imaging features of ES were reviewed in detail, and the anatomical structure and epidemiology of ITF were briefly introduced.

SOURCES

We performed a systematic search from 3 databases, CNKI(China National Knowledge Internet), FMRS(Foreign Medical Literature Retrieval Service, Shenzhen METSTR Technology CO., Led. China), and PubMed, to obtain literature from January 1970 to July 2020. Epithelioid sarcoma, head and neck regions, infratemporal fossa, diagnostic imaging, anatomy, MRI, and CT were used as keywords for advanced retrieval. A study had to be found eligible for inclusion to be closely related to ES and/or ITF. A total of 129 related pieces of literature were retrieved successfully, of which 37 were closely related to this study. The case report in this article is from the Affiliated Hospital of North Sichuan Medical College. The present study was approved by the institutional review board of the Affiliated Hospital of North Sichuan Medical College and a written informed consent for the publication of the case was obtained from the patient.

CASE PRESENTATION

A 33-year-old man accidentally found a slowly growing, painless mass in the left cheek more than a month ago. On plain computed tomography (CT) scan of the outpatient department, an oval slightly low-density mass with well-defined and uniform boundary in the infratemporal fossa was revealed, and on the contrast-enhanced scan, it was homogeneous and moderately enhanced. Initially, the CT appearance favored benign lesions. However, the possibility of a malignant tumor can not be excluded completely. Finally, the patient was referred to the inpatient department a tumor arose from IF and underwent a selective operation. The tumor was completely removed. Histologic findings were compatible with epithelioid sarcoma. Post-operatively, the patient received 2 cycles of radiotherapy, and there was no evidence of recurrence after 6 months follow- up.

CONCLUSION

The imaging manifestations of ES are various. The anatomic structure of ITF is complex and the pathological types are various. It should be very careful in the qualitative diagnosis of tumors from the ITF, and advanced imaging techniques will be useful in imaging diagnosis.

Epithelioid Sarcoma-From Genetics to Clinical Practice

Epithelioid sarcoma is a mesenchymal soft tissue sarcoma often arising in the extremities, usually in young adults with a pick of incidence at 35 years of age. Epithelioid sarcoma (ES) is characterized by the loss of SMARCB1/INI1 (integrase interactor 1) or other proteins of the SWI/SNF complex. Two distinct types, proximal and distal, with varying biology and treatment outcomes, are distinguished. ES is known for aggressive behavior, including a high recurrence rate and regional lymph node metastases. An optimal long-term management strategy is still to be defined. The best treatment of localized ES is wide surgical resection. Neo-adjuvant or adjuvant radiotherapy may be recommended, as it reduces the local recurrence rate. Sentinel lymph node biopsy should be considered in ES patients. Patients with metastatic ES have a poor prognosis with an expected median overall survival of about a year. Doxorubicin-based regimens are recommended for advanced ES. Tazemetostat, an EZH2 methyltransferase, has shown promising results in ES patients. Novel therapies, including immunotherapy, are still needed.

Metastatic Soft Tissue Sarcomas in Adolescents and Young Adults: A Specialist Center Experience

Purpose: Soft tissue sarcomas (STS) account for 8% of all cancers in adolescents and young adults (AYAs). Metastatic STS contribute significantly to disease-related mortality in this age group; however, data are limited due to under-representation in clinical trials. Methods: AYAs aged 18-39 years, diagnosed with metastatic STS between 1990 and 2012, were identified from The Royal Marsden Hospital database. Outcomes of interest were clinical characteristics, treatment patterns, overall survival (OS), and prognostic factors. Results: Overall, 455 patients were included. Median age at diagnosis of metastatic STS was 33 years (interquartile range [IQR] 27-37 years). The most common histological subtypes were leiomyosarcoma (n = 68, 15%), synovial sarcoma (n = 68, 15%), Ewing sarcoma (n = 44, 10%), and rhabdomyosarcoma (n = 35, 8%). Treatments included systemic therapy (n = 395, 87%; median 2 lines [IQR 1-3]; clinical trial n = 93, 22%), radiotherapy (n = 297, 66%), and metastasectomy (n = 191, 43%). Median duration between last chemotherapy regimen and death was 4.6 months (IQR 2-10). Median OS was 19.2 months (95% confidence interval [CI] 15.8-22.2); 5-year OS was 16%. Of common subtypes, patients with rhabdomyosarcoma had the worst OS (8.8 months; 95% CI 7.9-11.4). Adverse prognostic factors included male gender, synchronous metastases, bone or liver metastases, first-line polychemotherapy, and no metastasectomy. Conclusions: Outcomes were variable; patients with supposed chemosensitive subtypes had particularly poor survival. The diverse behavior of STS in AYAs highlights the need for subtype-specific clinical trials.