Clinical Activity of Pazopanib in Patients with Advanced Desmoplastic Small Round Cell Tumor

Abdominopelvic desmoplastic small round cell tumor with metastasis: A case report and literature review

RATIONALE

Desmoplastic small round cell tumor (DSRCT) is a rare and rapidly metastasizing soft tissue sarcoma, distinguished by its unique cell morphology and pleomorphic differentiation.

PATIENT CONCERNS

This report describes the case of an 18-year-old male diagnosed with abdominopelvic DSRCT exhibiting metastases to the peritoneum, liver, pleura, bone, and muscle. The patient primarily presented with symptoms of incomplete intestinal obstruction and an abdominal mass.

DIAGNOSES

Colonoscopy revealed lumen stenosis caused by external compression mass. Contrast-enhanced computed tomography and 18F-fluorodeoxyglucose positron emission tomography/computed tomography revealed multiple lesions in the abdominopelvic cavity. A needle biopsy of an abdominal wall lesion established it as a malignant tumor, origin unknown. Immunohistochemical staining post-surgery showed positive results for Cytokeratin (CK), CK7, Desmin, Vimentin, Caudal type homeobox 2 (CDX2), and Ki-67. Fluorescence in situ hybridization analysis revealed an Ewing sarcoma breakpoint region 1/EWS RNA binding protein 1 (EWSR1) rearrangement, and next-generation sequencing identified an EWSR1-Wilms tumor protein 1 (WT1) gene fusion.

INTERVENTIONS

The patient underwent laparoscopic exploratory surgery, which encompassed biopsy, ascites drainage, adhesion lysis, reinforcement of weakened sections of the small intestinal walls, and repositioning of twisted intestines. Postoperatively, the treatment protocol included fasting, rehydration, gastrointestinal decompression, and parenteral nutrition. However, the patient did not received chemotherapy.

OUTCOMES

The patient declined further treatment and deceased in early November.

LESSONS

This case highlights the nonspecific nature of DSRCT symptoms. In clinical practice, it is crucial to meticulously evaluate unexplained intestinal obstruction in young patients, considering DSRCT as a differential diagnosis to avoid delays in diagnosis.

Treatment of Abdominal Desmoplastic Small Round Cell Tumor Induces Acute Myeloid Leukemia-M5: A Case Report and Literature Review

Desmoplastic small round cell tumor (DSRCT) is a rare and highly aggressive malignancy. Most patients are diagnosed at a late stage with poor prognosis. The treatment usually includes combined intensive chemotherapy, cytoreductive surgery, radiotherapy, and targeted therapy. Due to the low incidence rate and dismal survival, there is currently a lack of case reports on DSRCT with concurrent leukemia. We report a case of a young patient who achieved disease stabilization for 14 months after receiving 6 cycles of chemotherapy and whole abdominal radiation therapy (WART), followed by consolidation treatment with anlotinib. However, the treatment was terminated due to the development of Acute Myeloid Leukemia-M5 (AML-M5). Multimodal therapy may provide a survival benefit for rare tumors that lack standard treatment. However, intensive chemotherapy and extensive radiotherapy carry a risk of inducing secondary malignancies. This is the first reported case of concurrent DSRCT and AML-M5 with short intervals between onset.

CXCR4-Directed Imaging and Endoradiotherapy in Desmoplastic Small Round Cell Tumors

Desmoplastic small round cell tumor (DSRCT) is a rare, radiosensitive, yet difficult-to-treat sarcoma subtype affecting predominantly male adolescents. Extensive intraperitoneal seeding is common and requires multimodal management. With no standard therapy established, the prognosis remains poor, and new treatment options are needed. We demonstrate the clinical potential of C-X-C motif chemokine receptor 4 (CXCR4)-directed imaging and endoradiotherapy in DSRCT. Methods: Eight male patients underwent dual-tracer imaging with [18F]FDG and CXCR4-directed [68Ga]pentixafor PET/CT. A visual comparison of both tracers, along with uptake quantification in active DSRCT lesions, was performed. [68Ga]pentixafor uptake was correlated with immunohistochemical CXCR4 expression on tumor cells. Four patients with end-stage progressive disease underwent CXCR4-based endoradiotherapy. We report the safety, response by RECIST 1.1, and survival after endoradiotherapy. Results: Uptake of [68Ga]pentixafor in tumor lesions was demonstrated in all patients with DSRCT, providing diagnostic power comparable to [18F]FDG PET. Corresponding CXCR4 expression was confirmed by immunohistochemistry in all DSRCT biopsies. Finally, 4 patients were treated with CXCR4-directed [90Y]endoradiotherapy, 3 in a myeloablative dose range with subsequent autologous stem cell transplantation. All 3 required transfusions, and febrile neutropenia occurred in 2 patients (resulting in 1 death). Notably, severe nonhematologic adverse events were absent. We observed signs of response in all 3 patients, translating into disease stabilization in 2 patients for 143 and 176 d, respectively. In the third patient, postmortem autopsy confirmed a partial pathologic response. Conclusion: We validated CXCR4 as a diagnostic biomarker and a promising target for endoradiotherapy in DSRCT, demonstrated its feasibility, and provided the first evidence of its clinical efficacy.

Small round cell sarcomas

Undifferentiated small round cell sarcomas (SRCSs) of bone and soft tissue comprise a heterogeneous group of highly aggressive tumours associated with a poor prognosis, especially in metastatic disease. SRCS entities mainly occur in the third decade of life and can exhibit striking disparities regarding preferentially affected sex and tumour localization. SRCSs comprise new entities defined by specific genetic abnormalities, namely EWSR1-non-ETS fusions, CIC-rearrangements or BCOR genetic alterations, as well as EWSR1-ETS fusions in the prototypic SRCS Ewing sarcoma. These gene fusions mainly encode aberrant oncogenic transcription factors that massively rewire the transcriptome and epigenome of the as yet unknown cell or cells of origin. Additional mutations or copy number variants are rare at diagnosis and, depending on the tumour entity, may involve TP53, CDKN2A and others. Histologically, these lesions consist of small round cells expressing variable levels of CD99 and specific marker proteins, including cyclin B3, ETV4, WT1, NKX3-1 and aggrecan, depending on the entity. Besides locoregional treatment that should follow standard protocols for sarcoma management, (neo)adjuvant treatment is as yet ill-defined but generally follows that of Ewing sarcoma and is associated with adverse effects that might compromise quality of life. Emerging studies on the molecular mechanisms of SRCSs and the development of genetically engineered animal models hold promise for improvements in early detection, disease monitoring, treatment-related toxicity, overall survival and quality of life.

Bevacizumab, With Sorafenib and Cyclophosphamide Provides Clinical Benefit for Recurrent or Refractory Osseous Sarcomas in Children and Young Adults

Objective

Children and adolescents with recurrent and metastatic solid tumors have a poor outcome. A previous phase 1 study (ANGIO1) targeting angiogenesis with bevacizumab, sorafenib, and cyclophosphamide, demonstrated a signal of activity in a subset of patients. Here we report the results of a cohort of pediatric and young adult patients treated at the recommended phase 2 doses.

Methods

Electronic medical records of patients with refractory or recurrent solid tumors who received ANGIO1 therapy were reviewed. Treatment cycles lasted 21 days and included bevacizumab, sorafenib, and cyclophosphamide. Toxicities were assessed using Common Terminology Criteria for Adverse Events, v5.0. Responses were evaluated using Response Evaluation Criteria in Solid Tumors (RECIST1.1).

Results

Thirty-nine patients (22 male, 17 female; median age 15 years; range 1-22 years) received the treatment regimen. The most common diagnoses included bone sarcomas (n=21; 14 Ewing sarcoma, 7 osteosarcoma) and soft tissue sarcomas (n=9; 2 rhabdomyosarcoma, 3 synovial sarcoma, 2 desmoplastic small round cell tumors, and 2 high-grade sarcoma). The most common Grade 3 non-hematologic toxicities included hypertension (2, 5.4%) and hematuria (2, 5.4%). Five patients (13.5%) had a pneumothorax (3 at progressive disease, 1 post lung biopsy, and 1 spontaneous). Common Grade 3/4 hematologic toxicities were lymphopenia (19, 51%) and leukopenia (13, 35%). Sixteen patients (43.2%) developed palmar-plantar erythrodysesthesia Grade 2 or less. A total of 297 cycles were administered. Twenty-three patients required a dose reduction of cyclophosphamide, sorafenib or bevacizumab during therapy, all of whom continued to have clinical benefit following dose modification. One patient (Ewing sarcoma) achieved a complete response after 11 cycles; 2 patients (Ewing sarcoma, high grade sarcoma) achieved a partial response following cycles 2 and 4, respectively and 20 patients had stable disease as a best response.

Conclusions

Intravenous bevacizumab combined with oral sorafenib and metronomic cyclophosphamide was tolerated and required minimal supportive care or additional clinic visits. Disease stabilization for prolonged time periods was observed in greater than half of the treated patients. Patients with bone sarcoma demonstrated a signal of activity suggesting possible benefit from incorporation of the therapy as a maintenance regimen in upfront setting, or as a palliative regimen.

The androgen receptor is a therapeutic target in desmoplastic small round cell sarcoma

Desmoplastic small round cell tumor (DSRCT) is an aggressive, usually incurable sarcoma subtype that predominantly occurs in post-pubertal young males. Recent evidence suggests that the androgen receptor (AR) can promote tumor progression in DSRCTs. However, the mechanism of AR-induced oncogenic stimulation remains undetermined. Herein, we demonstrate that enzalutamide and AR-directed antisense oligonucleotides (AR-ASO) block 5α-dihydrotestosterone (DHT)-induced DSRCT cell proliferation and reduce xenograft tumor burden. Gene expression analysis and chromatin immunoprecipitation sequencing (ChIP-seq) were performed to elucidate how AR signaling regulates cellular epigenetic programs. Remarkably, ChIP-seq revealed novel DSRCT-specific AR DNA binding sites adjacent to key oncogenic regulators, including WT1 (the C-terminal partner of the pathognomonic fusion protein) and FOXF1. Additionally, AR occupied enhancer sites that regulate the Wnt pathway, neural differentiation, and embryonic organ development, implicating AR in dysfunctional cell lineage commitment. Our findings have direct clinical implications given the widespread availability of FDA-approved androgen-targeted agents used for prostate cancer.

Androgen receptor can promote tumour progression in desmoplastic small round cell tumour (DSRCT), an aggressive paediatric malignancy that predominantly affects young males. Here, the authors show that DSRCT is an AR-driven malignancy and sensitive to androgen deprivation therapy

Phase II Study of ONC201 in Neuroendocrine Tumors including Pheochromocytoma-Paraganglioma and Desmoplastic Small Round Cell Tumor

PURPOSE

Tumor dopamine-like DRD2 receptor expression is higher in pheochromocytoma-paraganglioma (PC-PG) compared with other cancers. ONC201 is a bitopic DRD2 antagonist with preclinical ONC201 activity in desmoplastic small round cell tumor (DSRCT).

PATIENTS AND METHODS

Patients (N = 30) with neuroendocrine tumors were treated on this investigator-initiated trial (NCT03034200). ONC201 dose and schedule were 625 mg orally weekly in cohorts A (PC-PG) + B (other neuroendocrine tumors) and 625 mg orally on 2 consecutive days each week in cohort C, which included 5 responding patients. The primary endpoint was radiographic response measured using RECIST. Secondary endpoints included progression-free survival, overall survival, and safety.

RESULTS

In arm A (n = 10; all PC-PG), 50% (5/10) exhibited a partial response (PR) and 2 additional patients had stable disease (SD) >3 months. Median duration of therapy for arm A patients was 9 months (range: 1.5-33 months) with 5 patients treated >1 year. In arm B (n = 12), there were 1 PR (DSRCT) and 2 SD (DSRCT; neuroblastoma) >3 months. Median duration of therapy in arm A was 18 months (range: 1-33 months) and arm B was 3 months (range: 1.5-33 months). Arm C PC-PG (N = 8) showed 1 PR and 7 SD at 3 months, with median duration of therapy >10 months. There was no decline in Karnofsky performance status at week 12 for 28 of 30 patients and no dose modification due to treatment-related adverse events.

CONCLUSIONS

Oral ONC201 was well tolerated in patients with metastatic neuroendocrine tumors and associated with clinical benefit, including tumor responses, particularly in some patients with DSRCT and the majority of patients with PC-PG. See related commentary by Owen and Trikalinos, p. 1748.

Desmoplastic small round cell tumor of the duodenum and rectum: Report of two cases

BACKGROUND

Primary desmoplastic small round cell tumor of the duodenum and rectum is rare, with rapid progression and strong infiltration. At present, there is no standard treatment scheme for this disease, and the prognosis is poor. The diagnosis depends on pathology and immunohist-ochemistry.

CASE SUMMARY

The clinical manifestation of Case 1 was abdominal pain, which was misdiagnosed as duodenal cancer. The final diagnosis was made by postoperative pathology. Multiple metastases still occurred after surgical resection and chemotherapy. The clinical manifestation of Case 2 was constipation. It was misdiagnosed as rectal cancer and surgical resection was performed. The final diagnosis was made by postoperative pathology.

CONCLUSION

Analyzing the clinical, imaging, and pathological features of desmoplastic small round cell tumor of the duodenum and rectum is conducive to more comprehensive understanding of atypical intestinal space occupying lesions and early diagnosis, early evaluation, and early treatment of the disease.

Intra-Abdominal Desmoplastic Small Round Cell Tumor: Current Treatment Options and Perspectives

Intra-abdominal desmoplastic small round cell tumor (IDSRCT) is a rare and highly malignant soft tissue neoplasm, which is characterized by rapid progression and poor prognosis. The mechanism underlying the development of this neoplasm remains elusive, but all cases are characterized by the chromosomal translocation t (11;22) (p13; q12), which results in a formation of EWSR1-WT1 gene fusion. The diagnosis of IDSRCT is often made with core-needle tissue biopsy specimens or laparoscopy or laparotomy. Immunohistochemical analyses have shown the co-expression of epithelial, neuronal, myogenic, and mesenchymal differentiation markers. FISH or reverse transcription polymerase chain reaction detecting EWS-WT1 fusion can be performed to assist in molecular confirmation. There is no standard of care for patients with IDSRCT currently, and majority of newly diagnosed patients received the aggressive therapy, which includes >90% resection of surgical debulking, high-dose alkylator-based chemotherapy, and radiotherapy. More recently, targeted therapy has been increasingly administered to recurrent IDSRCT patients and has been associated with improved survival in clinical conditions. Immunotherapy as a possible therapeutic strategy is being explored in patients with IDSRCT. In this review, we summarize currently available knowledge regarding the epidemiology, potential mechanisms, clinical manifestations, diagnosis, treatment, and prognosis of IDSRCT to assist oncologists in comprehensively recognizing and accurately treating this malignancy.

The Evolving Role of Radiotherapy for Pediatric Cancers With Advancements in Molecular Tumor Characterization and Targeted Therapies

Ongoing rapid advances in molecular diagnostics, precision imaging, and development of targeted therapies have resulted in a constantly evolving landscape for treatment of pediatric cancers. Radiotherapy remains a critical element of the therapeutic toolbox, and its role in the era of precision medicine continues to adapt and undergo re-evaluation. Here, we review emerging strategies for combining radiotherapy with novel targeted systemic therapies (for example, for pediatric gliomas or soft tissue sarcomas), modifying use or intensity of radiotherapy when appropriate via molecular diagnostics that allow better characterization and individualization of each patient’s treatments (for example, de-intensification of radiotherapy in WNT subgroup medulloblastoma), as well as exploring more effective targeted systemic therapies that may allow omission or delay of radiotherapy. Many of these strategies are still under investigation but highlight the importance of continued pre-clinical and clinical studies evaluating the role of radiotherapy in this era of precision oncology.

Hyperthermic intraperitoneal chemotherapy (HIPEC) as another treatment modality for desmoplastic round cell tumour patients: first paediatric experience from UK

We present the first young paediatric patient with desmoplastic small round cell tumour (DSRCT) treated in UK with hyperthermic intraperitoneal chemotherapy (HIPEC). A 7-year-old girl was diagnosed with abdominal DSRCT with peritoneal and liver metastases. After six cycles of chemotherapy she obtained a partial response, including almost complete resolution of the two liver metastases. It was decided to pursue cytoreductive surgery (CRS) combined with HIPEC, a procedure commonly performed in adults, but seldom in a child. The surgery was macroscopically complete and the HIPEC uncomplicated. She continued treatment without delays, including whole abdomino-pelvic radiotherapy and maintenance chemotherapy (cyclophosphamide/vinorelbine for 12 months). She is currently in complete remission 4 months after end of treatment and 26 months after diagnosis. HIPEC was made possible by successful collaboration between multiple teams. CRS-HIPEC proved to be safe and feasible and could be offered to other children with diagnoses of peritoneal malignancies across the UK.

Desmoplastic Small Round Cell Tumor: A Review of Main Molecular Abnormalities and Emerging Therapy

Simple Summary

Desmoplastic small round cell tumor is a rare neoplasm with extremely aggressive behavior. Despite the multimodal treatment for newly diagnosed patients with chemotherapy, cytoreductive surgery and radiation, the cure rate is still low. For relapsed or progressive disease, there is limited data regarding second and third-line therapies. Novel agents have shown only modest activity. Recent molecular changes have been identified in this disease and this opens opportunities to be explored in future clinical trials.

Abstract

Desmoplastic small round cell tumor (DSRCT) is an extremely rare, aggressive sarcoma affecting adolescents and young adults with male predominance. Generally, it originates from the serosal surface of the abdominal cavity. The hallmark characteristic of DSRCT is the EWSR1–WT1 gene fusion. This translocation up-regulates the expression of PDGFRα, VEGF and other proteins related to tumor and vascular cell proliferation. Current management of DSRCT includes a combination of chemotherapy, radiation and aggressive cytoreductive surgery plus intra-peritoneal hyperthermic chemotherapy (HIPEC). Despite advances in multimodal therapy, outcomes remain poor since the majority of patients present disease recurrence and die within three years. The dismal survival makes DSRCT an orphan disease with an urgent need for new drugs. The treatment of advanced and recurrent disease with tyrosine kinase inhibitors, such as pazopanib, sunitinib, and mTOR inhibitors was evaluated by small trials. Recent studies using comprehensive molecular profiling of DSRCT identified potential therapeutic targets. In this review, we aim to describe the current studies conducted to better understand DSRCT biology and to explore the new therapeutic strategies under investigation in preclinical models and in early phase clinical trials.

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.

Use of Antiangiogenic Therapies in Pediatric Solid Tumors

Cancer is an important cause of death in childhood. In recent years, scientists have made an important effort to achieve greater precision and more personalized treatments against cancer. But since only a few pediatric patients have identifiable therapeutic targets, other ways to stop the neoplastic cell proliferation and dissemination are needed. Therefore, the inhibition of general processes involved in the growth and behavior of tumors can be a relevant strategy for the development of new cancer therapies. In the case of solid tumors, one of these processes is angiogenesis, essential for tumor growth and generation of metastases. This review summarizes the results obtained with the use of antiangiogenic drugs in the main pediatric malignant solid tumors and also an overview of clinical trials currently underway. It should be noted that due to the rarity and heterogeneity of the different types of pediatric cancer, most studies on antiangiogenic drugs include only a small number of patients or isolated clinical cases, so they are not conclusive and further studies are needed.

Desmoplastic Small Round Cell Tumors: A review with focus on clinical management and therapeutic options

Desmoplastic Small Round Cell Tumors (DSRCTs) are an entity of rare, aggressive soft tissue sarcomas described by Gerald and Rosai in 1989. It predominantly affects male adolescents and young adults, with a peak incidence between an age of 20 and 30 years. Typically, DSRCT demonstrate as multiple small tumor nodules within the abdominal cave, retroperitoneum and pelvis. In more than 50% of the cases, the neoplasm presents metastatic at the timepoint of diagnosis. Histologically, DSRCTs have a characteristic morphology with sharply demarcated islands of uniform small round cells in abundant desmoplastic stroma organized in loose extracellular matrix. Immunohistochemistry reveals a polyphenotypic differentiation with co-expression of epithelial, myogenic, mesenchymal and neural markers. The morphology is highly variable and can hinder diagnosis. The most consistent molecular characteristic of DSRCT is the reciprocal t(11;22)(p13q12) translocation. This mutation leads to a formation of the EWSR1-WT1 fusion oncogene, which encodes for a chimeric protein with transcriptional regulatory activity and is regarded as driving source of the disease. To date, there is no standardized concept for clinical management, staging and treatment. Patients receive an aggressive multimodal therapeutic approach consisting of chemotherapy, radical surgical procedures, hyperthermic, intraperitoneal chemotherapy (HIPEC) and radiation. New targeted therapies are used in experimental settings as salvage therapy. So far, none of these therapies showed significant long-term success. This review gives an overview of diagnostic difficulties and pitfalls, discusses therapeutic strategies and highlights options for clinical management.

Advances in the Management of Pediatric Sarcomas

PURPOSE OF REVIEW

The prognosis of pediatric patients who present with metastatic or recurrent sarcomas remains poor. In this review, we summarize the advances in the management of metastatic and relapsed pediatric sarcoma by highlighting recent and future clinical trials.

RECENT FINDINGS

Research into the identification of novel therapies for refractory pediatric sarcomas continues to advance. Outcomes have not improved in several decades underlying a need for improved understanding of the biology behind these tumors and the identification of novel therapeutic molecular targets that can be exploited pharmacologically. Multiple challenges remain for novel therapy in sarcomas such as the selection of effective targets, management of toxicities, and the tumor microenvironment. Many unique challenges remain in the treatment of patients with refractory pediatric sarcomas. Multiple strategies and targets are under investigation that hold promise.

Desmoplastic Small Round Cell Tumor of the Kidney: Report of a Case, Literature Review, and Comprehensive Discussion of the Distinctive Morphologic, Immunohistochemical, and Molecular Features in the Differential Diagnosis of Small Round Cell Tumors Affecting the Kidney

Desmoplastic small round cell tumor (DSRCT) is a rare, highly aggressive neoplasm typically presenting with widespread involvement of the abdominopelvic peritoneum of adolescent males, usually without organ-based primary. Although it is believed to originate from the serous (mainly peritoneal) membranes, intracranial, sinonasal, intraosseous, and other soft tissue sites are also documented. A chromosomal translocation t(11:22)(p13;q12) signature that fuses EWSR1 and WT1 genes results in the production of a chimeric protein with transcriptional regulatory activity that drives oncogenesis. Integration of clinical, morphologic, immunohistochemical, and genetic data is necessary to arrive at the correct diagnosis, especially when the tumor arises in an atypical site. A 15-year-old male presented with hematuria and was found to have a large renal tumor associated with adrenal, liver, lung, and bone metastases. Histopathologic and immunophenotypic features were distinctive for DSRCT. This diagnosis was confirmed by means of fluorescence in situ hybridization and cytogenetic analysis, which documented the pathognomonic t(11;22) translocation, and by reverse transcription polymerase chain reaction on snap-frozen tissue, which revealed the EWSR1/WT1-specific chimeric transcript. Despite high-dose chemotherapy and radiation therapy targeted to a single T11 vertebral metastasis, the disease progressed, and the patient died 4 years after the diagnosis. A search of electronic databases for DSRCT yielded 16 cases of well-documented renal primaries out of around 1570 cases from all sites gathered from the global literature. Desmoplastic small round blue cell tumor and other primary renal tumors considered in the differential diagnosis with DSRCT are discussed.

Clinical Characteristics, Management, and Outcomes of 19 Nonpediatric Patients with Desmoplastic Small Round Cell Tumor: A Cohort of Brazilian Patients

Desmoplastic small round cell tumor (DSRCT) is a rare and aggressive mesenchymal malignancy, usually affecting young males. There is no consensus on the best therapeutic approach. We seek to characterize a cohort of nonpediatric patients with DSRCT treated at a large Brazilian cancer center. We performed a retrospective analysis of patients with histologically confirmed DSRCT referred to our institution (2007–2020). Clinical and imaging data were extracted and summarized with descriptive statistics. Survival analyses were conducted by the Kaplan–Meier method and compared with the log-rank test. We included 19 patients with DSRCT, the median age at diagnosis was 26 years (range: 15–41 years), and 68% were male. Ninety percent presented with abdominopelvic masses, and 32% had extra-abdominal metastasis at diagnosis. Eleven patients (58%) underwent surgery, four patients (21%) received whole abdominal adjuvant radiotherapy, and five patients (26%) had hyperthermic intraperitoneal chemotherapy. Median OS was 27 months (interquartile range: 18–51 m). The five-year OS rate was 12%. Our data confirm the aggressiveness of DSRCT despite intense multimodality treatment. Outcomes of patients treated in a reference cancer center in a developing country are similar to cancer centers in developed nations. Multicenter cooperation is urgent to the development of clinical trials and to improve diagnosis and treatment efficacy.

The use of interval-compressed chemotherapy with the addition of vincristine, irinotecan, and temozolomide for pediatric patients with newly diagnosed desmoplastic small round cell tumor

BACKGROUND

Desmoplastic small round cell tumor (DSRCT) is a rare aggressive sarcoma that affects children and young adults, and portends poor outcomes despite intensive multimodal treatment approaches. We report toxicity, response, and outcomes of patients with DSRCT treated with the addition of vincristine, irinotecan, and temozolomide (VIT) to interval-compressed chemotherapy as per Children's Oncology Group ARST08P1.

METHODS

All newly diagnosed pediatric patients with DSRCT treated at Dana-Farber Cancer Institute and Boston Children's Hospital between 2014 and 2019 as per ARST08P1, Arm P2 with replacement of VAC cycles with VIT, were identified. Medical records were reviewed for clinical and disease characteristics, and treatment response and outcomes.

RESULTS

Six patients were treated as per the above regimen. Median age at diagnosis was 15.1 years (range 3.2-16.4) and five patients were male. Five patients had abdominal primary tumors, of which one had exclusively intraabdominal and four had extraabdominal metastases. Two initial cycles of VIT were well tolerated with nausea, vomiting, diarrhea, and constipation as the most common adverse events. Overall response rate defined as partial or complete response after two initial cycles of VIT was 50%. For local control, all patients had surgical resection followed by radiotherapy, and two patients received hyperthermic intraperitoneal chemotherapy at the time of surgery. Of the four patients who have completed therapy to date, three remain disease-free with median follow-up time of 46.7 months.

CONCLUSIONS

The addition of VIT to interval-compressed chemotherapy is tolerable and active in DSRCT, with activity warranting additional investigation.

Mini-Review on Targeted Treatment of Desmoplastic Small Round Cell Tumor

Desmoplastic small round cell tumor (DSRCT) is a devastating disease which most commonly affects adolescents, with a male predominance. Despite the best multimodality treatment efforts, most patients will ultimately not survive more than 3-5 years after diagnosis. Some research trials in soft-tissue sarcoma and Ewing sarcoma include DSRCT patients but few studies have been tailored to the specific clinical needs and underlying cytogenetic abnormalities characterizing this disease such as the typical EWSR1-WT1 gene fusion. Downstream activation of EWSR1-WT1 gene fusion includes signaling pathways of platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and insulin growth factor (IGF)-1. Other biological pathways that are activated and expressed in DSRCT cells include endothelial growth factor receptor (EGFR), androgen receptor pathway, c-KIT, MET, and transforming growth factor (TGF) beta. Investigation of somatic mutations, copy number alterations (CNA), and chromosomes in DSRCT samples suggests that deregulation of mesenchymal-epithelial reverse transition (MErT)/epithelial-mesenchymal transition (EMT) and DNA damage repair (DDR) may be important in DSRCT. This mini review looks at known druggable targets in DSRCT and existing clinical evidence for targeted treatments, particularly multityrosine kinase inhibitors such as pazopanib, imatinib, and sorafenib alone or in combination with other agents such as mTOR (mammalian target of rapamycin) inhibitors. The aim is to increase shared knowledge about current available treatments and identify gaps in research to further efforts toward clinical development of targeted agents.

Chicago Consensus Working Group. The Chicago Consensus on Peritoneal Surface Malignancies: Management of Desmoplastic Small Round Cell Tumor, Breast, and Gastrointestinal Stromal Tumors

The Chicago Consensus Working Group provides multidisciplinary recommendations for the management of desmoplastic small round cell tumor, breast, and gastrointestinal stromal tumor specifically related to peritoneal surface malignancy. These guidelines are developed with input from leading experts including surgical oncologists, medical oncologists, pathologists, radiologists, palliative care physicians, and pharmacists. These guidelines recognize and address the emerging need for increased awareness in the appropriate management of peritoneal surface disease. They are not intended to replace the quest for higher levels of evidence.

The Chicago Consensus on peritoneal surface malignancies: Management of desmoplastic small round cell tumor, breast, and gastrointestinal stromal tumors

The Chicago Consensus Working Group provides multidisciplinary recommendations for the management of desmoplastic small round cell, breast, and gastrointestinal stromal tumors specifically related to peritoneal surface malignancy. These guidelines are developed with input from leading experts, including surgical oncologists, medical oncologists, pathologists, radiologists, palliative care physicians, and pharmacists. These guidelines recognize and address the emerging need for increased awareness in the appropriate management of peritoneal surface disease. They are not intended to replace the quest for higher levels of evidence.

Olaparib and temozolomide in desmoplastic small round cell tumors: a promising combination in vitro and in vivo

Purpose

Desmoplastic small round cell tumors (DSRCTs) are highly malignant and very rare soft tissue sarcomas with a high unmet need for new therapeutic options. Therefore, we examined poly(ADP-ribose) polymerase 1 (PARP1) and Schlafen-11 (SLFN11) expression in DSRCT tumor tissue and the combination of PARP inhibitor olaparib with the alkylating agent temozolomide (TMZ) in a preclinical DSRCT model.

Methods

PARP1 and SLFN11 have been described as predictive biomarkers for response to PARP inhibition. Expression of PARP1 and SLFN11 was assessed in 16 and 12 DSRCT tumor tissue samples, respectively. Effects of single-agent olaparib, and olaparib and TMZ combination treatment were examined using the preclinical JN-DSRCT-1 model. In vitro, single-agent and combination treatment effects on cell viability, the cell cycle, DNA damage and apoptosis were examined. Olaparib and TMZ combination treatment was also assessed in vivo.

Results

PARP1 and SLFN11 expression was observed in 100% and 92% of DSRCT tumor tissues, respectively. Olaparib treatment reduced cell viability and cell migration in a dose-dependent manner in vitro. Drug synergy between olaparib and TMZ was observed in vitro and in vivo. Combination treatment led to a cell-cycle arrest and induction of DNA damage and apoptosis, even when combined at low dosages.

Conclusion

We show high PARP1 and SLFN11 expression in DSRCT tumor material and antitumor effects following olaparib and TMZ combination treatment in a preclinical DSRCT model. This suggests that olaparib and TMZ combination treatment could be a potential treatment option for DSRCTs.

Electronic supplementary material

The online version of this article (10.1007/s00432-020-03211-z) contains supplementary material, which is available to authorized users.

Systemic therapy in pediatric-type soft-tissue sarcoma

Soft-tissue sarcoma (sts) is rare and represents approximately 7% of cancers in children and in adolescents less than 20 years of age. Rhabdomyosarcoma (rms) is most prevalent in children less than 10 years of age and peaks again during adolescence (16-19 years of age). Multi-agent chemotherapy constitutes the mainstay of treatment for rms. In other non-rhabdomyosarcoma soft-tissue tumours, such as synovial sarcoma, evidence for routine use of chemotherapy is less robust, and alternative treatment options, including targeted agents and immunotherapy, are being explored. In this review, we focus on chemotherapy for pediatric-type rms and discuss the advances and challenges in systemic treatment for select non-rhabdomyosarcoma soft-tissue tumours in children and adolescents. We support an increasingly cooperative approach for treating pediatric and adult sts.

An update in the management of pediatric sarcoma

PURPOSE OF REVIEW

Nonrhabdomyosarcoma soft tissue sarcoma (NRSTS) is a rare subgroup of malignancy in childhood that is composed of a variety of soft tissue and bony tumors. Prognosis for resectable localized disease is usually good and improved with systemic treatment. However, survival from locally advanced and metastatic disease remains poor. There have been numerous preclinical and clinical studies to define histopathology, biology, and genetic alteration of sarcomas. The purpose of this review is to clarify the progress in the management of NRSTS.

RECENT FINDINGS

Genomic analysis, including the use of next-generation sequencing, has revealed fusion transcripts or specific genetic alterations which provide diagnostic biomarkers and potential targets for novel therapies.

SUMMARY

Most cases are sporadic, but some are associated with genetic predispositions. Most present as a painless mass and diagnosis is frequently delayed because of a low index of suspicion. There is a wide array of histopathological subtypes. Investigations usually involve core, incisional or excisional biopsy for tissue diagnosis, and cross-sectional and nuclear imaging for staging. Management of pediatric sarcoma is largely dependent on the patient's histopathological diagnosis, age, disease stage, and co-morbidities but usually involves a combination of systemic and local therapies. Preclinical studies and phase I/II trials of newer targeted therapies are ongoing.

Pazopanib in advanced soft tissue sarcomas

Pazopanib is the first and only tyrosine kinase inhibitor currently approved for the treatment of multiple histological subtypes of soft tissue sarcoma (STS). Initially developed as a small molecule inhibitor of vascular endothelial growth factor receptors, preclinical work indicates that pazopanib exerts an anticancer effect through the inhibition of both angiogenic and oncogenic signaling pathways. Following the establishment of optimal dosing and safety profiles in early phase studies and approval for the treatment of advanced renal cell carcinoma, pazopanib was investigated in STS. A landmark phase III randomized study demonstrated improved progression-free survival with pazopanib compared to that with placebo in pretreated patients with STS of various subtypes. The efficacy of pazopanib in specific STS subtypes has been further described in real-world-based case series in both mixed and subtype-specific STS cohorts. At present, there are no clinically validated predictive biomarkers for use in selecting patients with advanced STS for pazopanib therapy, limiting the clinical effectiveness and cost-effectiveness of the drug. In this review, we summarize the preclinical and clinical data for pazopanib, outline the evidence base for its effect in STS and explore reported studies that have investigated putative biomarkers.

Desmoplastic small round cell tumors: Multimodality treatment and new risk factors

Background

To evaluate optimal therapy and potential risk factors.

Methods

Data of DSRCT patients <40 years treated in prospective CWS trials 1997‐2015 were analyzed.

Results

Median age of 60 patients was 14.5 years. Male:female ratio was 4:1. Tumors were abdominal/retroperitoneal in 56/60 (93%). 6/60 (10%) presented with a localized mass, 16/60 (27%) regionally disseminated nodes, and 38/60 (63%) with extraperitoneal metastases. At diagnosis, 23/60 (38%) patients had effusions, 4/60 (7%) a thrombosis, and 37/54 (69%) elevated CRP. 40/60 (67%) patients underwent tumor resection, 21/60 (35%) macroscopically complete. 37/60 (62%) received chemotherapy according to CEVAIE (ifosfamide, vincristine, actinomycin D, carboplatin, epirubicin, etoposide), 15/60 (25%) VAIA (ifosfamide, vincristine, adriamycin, actinomycin D) and, 5/60 (8%) P6 (cyclophosphamide, doxorubicin, vincristine, ifosfamide, etoposide). Nine received high‐dose chemotherapy, 6 received regional hyperthermia, and 20 received radiotherapy. Among 25 patients achieving complete remission, 18 (72%) received metronomic therapies. Three‐year event‐free (EFS) and overall survival (OS) were 11% (±8 confidence interval [CI] 95%) and 30% (±12 CI 95%), respectively, for all patients and 26.7% (±18.0 CI 95%) and 56.9% (±20.4 CI 95%) for 25 patients achieving remission. Extra‐abdominal site, localized disease, no effusion or ascites only, absence of thrombosis, normal CRP, complete tumor resection, and chemotherapy with VAIA correlated with EFS in univariate analysis. In multivariate analysis, significant factors were no thrombosis and chemotherapy with VAIA. In patients achieving complete remission, metronomic therapy with cyclophosphamide/vinblastine correlated with prolonged time to relapse.

Conclusion

Pleural effusions, venous thrombosis, and CRP elevation were identified as potential risk factors. The VAIA scheme showed best outcome. Maintenance therapy should be investigated further.

Translocation-Related Sarcomas

Chromosomal translocations are observed in approximately 20% of soft tissue sarcomas (STS). With the advances in pathological examination technology, the identification of translocations has enabled precise diagnoses and classifications of STS, and it has been suggested that the presence of and differences in translocations could be prognostic factors in some translocation-related sarcomas. Most of the translocations in STS were not regarded as targets of molecular therapies until recently. However, trabectedin, an alkylating agent, has shown clinical benefits against translocation-related sarcoma based on a modulation of the transcription of the tumor's oncogenic fusion proteins. Many molecular-targeted drugs that are specific to translocations (e.g., anaplastic lymphoma kinase and tropomyosin kinase related fusion proteins) have emerged. The progress in gene technologies has allowed researchers to identify and even induce new translocations and fusion proteins, which might become targets of molecular-targeted therapies. In this review, we discuss the clinical significance of translocation-related sarcomas, including their diagnoses and targeted therapies.

Multimodality Treatment of Desmoplastic Small Round Cell Tumor: Chemotherapy and Complete Cytoreductive Surgery Improve Patient Survival

Purpose: Desmoplastic small round cell tumor (DSRCT), which harbors EWSR1-WT1 t(11;22)(p13:q12) chromosomal translocation, is an aggressive malignancy that typically presents as intra-abdominal sarcomatosis in young males. Given its rarity, optimal treatment has not been defined.Experimental Design: We conducted a retrospective study of 187 patients with DSRCT treated at MD Anderson Cancer Center over 2 decades. Univariate and multivariate regression analyses were performed. We determined whether chemotherapy, complete cytoreductive surgery (CCS), hyperthermic intraperitoneal cisplatin (HIPEC), and/or whole abdominal radiation (WART) improve overall survival (OS) in patients with DSRCT. Critically, because our institutional practice limits HIPEC and WART to patients with less extensive, potentially resectable disease that had benefited from neoadjuvant chemotherapy, a time-variant analysis was performed to evaluate those adjunct treatment modalities.Results: The pre-2003 5-year OS rate of 5% has substantially improved to 25% with the advent of newer chemotherapies and better surgical and radiotherapy techniques (HR, 0.47; 95% CI, 0.29-0.75). Chemotherapy response (log rank P = 0.004) and CCS (log rank P < 0.0001) were associated with improved survival. Although WART and HIPEC lacked statistical significance, our study was not powered to detect their potential impact upon OS.Conclusions: Improved 3- and 5-year OS were observed following multidisciplinary treatment that includes Ewing sarcoma (ES)-based chemotherapy and complete tumor cytoreductive surgery, but few if any patients are cured. Prospective randomized studies will be required to prove whether HIPEC or WART are important. In the meantime, chemotherapy and CCS remain the cornerstone of treatment and provide a solid foundation to evaluate new biologically targeted therapies. Clin Cancer Res; 24(19); 4865-73. ©2018 AACR.

Effective treatment of apatinib in desmoplastic small round cell tumor: a case report and literature review

BACKGROUND

Desmoplastic small round cell tumor (DSRCT) is a rare malignant sarcoma with poor prognosis due to lack of effective treatments. Apatinib is a new potent oral small-molecule tyrosine kinase inhibitor, and targets the intracellular domain of vascular endothelial growth factor receptor 2 (VEGFR-2). In this study, we presented a case of intra-abdominal DSRCT which was effectively treated by apatinib.

CASE PRESENTATION

A 32-year-old man was admitted due to increasing urination frequency and palpable mass in right lower abdomen for 2 months. The mass was resected and diagnosed DSRCT. The patient refused chemotherapy and radiotherapy,and used Chinese medicine only. Six months after the surgery, the patient re-hospitalized due to growing abdominal mass and ascites. Intraperitoneal cisplatin treatment showed little effect. Apatinib was then recommended. Apatinib revealed outstanding effect on reducing mass size and ascites during 2-month treatment. Apatinib therapy continued for additional 2 months, and the patient was in good condition. The only toxicity was hand-food syndrome, which was controllable and well tolerated.

CONCLUSION

It is the first report that apatinib is effective on DSRCT. This report may provide an additional option for the treatment of metastatic DSRCT.