Whole abdominopelvic intensity-modulated radiation therapy for desmoplastic small round cell tumor after surgery

Multiple Abdominal Desmoplastic Small Round-Cell Tumors Treated With Fan Beam Computed Tomography-Guided Adaptive Radiotherapy (FBCT-gART): A Case Report

Desmoplastic small round cell tumor (DSRCT) is a rare and highly aggressive soft tissue tumor that predominantly affects the abdominal and pelvic regions of adolescent males. This case report presents our clinical experience of treating a 33-year-old male with multifocal peritoneal DSRCT using fan beam computed tomography-guided adaptive radiotherapy (FBCT-gART). The patient presented with abdominal pain and was diagnosed with DSRCT following imaging and biopsy. Despite initial treatment with surgery, chemotherapy, and targeted therapy, the patient experienced multifocal peritoneal recurrence. Due to the considerable mobility of the abdominal tumors and the associated risks to adjacent critical organs, the patient underwent daily online FBCT-gART. The prescribed dose regimen was 54 Gy delivered in 27 fractions at 2 Gy per fraction; however, the patient ultimately received only 25 treatments for personal reasons. This case report evaluates the technical workflow of using FBCT-gART for DSRCT and discusses its dosimetric advantages over non-adaptive radiotherapy.

Intra-abdominal desmoplastic small round cell tumor: The European pediatric Soft tissue sarcoma Study Group (EpSSG) experience

BACKGROUND

This study describes the clinical findings of a consecutive series of pediatric and adolescent patients with a diagnosis of intra-abdominal desmoplastic small round cell tumor (DSRCT) prospectively enrolled in European pediatric Soft tissue sarcoma Study Group (EpSSG) protocols: the BERNIE study, the EpSSG MTS 2008 study, and the EpSSG NRSTS 2005 study.

METHODS

Patients aged less than 21 years with a diagnosis of DSRCT arising in the abdomen were included. All trials recommended a multimodal approach including intensive multidrug chemotherapy and loco-regional treatment with surgery and/or radiotherapy whenever possible.

RESULTS

The analysis included 32 cases (median age 13.7 years, male:female ratio 1.5:1). Three patients had localized tumors, seven had regionally disseminated disease, and 22 extraperitoneal metastases. All but one patient received multidrug chemotherapy and 11 had maintenance chemotherapy. Loco-regional treatment consisted of surgery only in seven cases, surgery plus adjuvant radiotherapy in 10, and radiotherapy only in six. Among the 17 cases who had radiotherapy, six had irradiation of the primary site, 10 had whole abdominopelvic radiotherapy plus boost to macroscopic residual disease, and one had irradiation to lung metastases only. With a median follow-up of 76 months (range: 18-124 months), 5-year event-free and overall survivals were 19.7% and 21.0%, respectively. Event-free survival was significantly worse for patients who did not receive loco-regional treatment (p-value .007).

CONCLUSIONS

The study confirmed that the outcome of patients with DSRCT remains dismal and did not improve over recent years despite an intensive multimodal treatment approach.

Desmoplastic small round cell tumor: from state of the art to future clinical prospects

INTRODUCTION

Desmoplastic small round cell tumor (DSRCT) is an extremely rare and highly aggressive soft tissue sarcoma, presenting mainly in male adolescents and young adults with multiple nodules disseminated within the abdominopelvic cavity. Despite a multimodal approach including aggressive cytoreductive surgery, intensive multi-agent chemotherapy, and postoperative whole abdominopelvic radiotherapy, the prognosis for DSRCT remains dismal. Median progression-free survival ranges between 4 and 21 months, and overall survival between 17 and 60 months, with the 5-year overall survival rate in the range of 10-20%.

AREA COVERED

This review discusses the treatment strategies used for DSRCT over the years, the state of the art of current treatments, and future clinical prospects.

EXPERT OPINION

The unsatisfactory outcomes for patients with DSRCT warrant investigations into innovative treatment combinations. An international multidisciplinary and multi-stakeholder collaboration, involving both pediatric and adult sarcoma communities, is needed to propel preclinical model generation and drug development, and innovative clinical trial designs to enable the timely testing of treatments involving novel agents guided by biology to boost the chances of survival for patients with this devastating disease.

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.

Late Toxicity After 3-Dimensional External Beam Radiotherapy Among Children With Cancer: A Systematic Review

Radiotherapy has evolved from 2-dimensional conventional radiotherapy (2D-RT) to 3-dimensional planned radiotherapy (3D-RT). Because 3D-RT improves conformity, an altered late health outcomes risk profile is anticipated. Here, we systematically reviewed the current literature on late toxicity after 3D-RT in children treated for cancer. PubMed was searched for studies describing late toxicity after 3D-RT for childhood cancer (below 21 y). Late toxicity was defined as somatic health outcomes occurring ≥90 days after treatment. We identified 13 eligible studies, describing most frequently head/neck area tumors. Included studies reported on crude frequencies of late toxicities including subsequent tumors and conditions of organ systems. Three studies offered a global assessment of the full spectrum of late toxicity; one study compared toxicities after 2D-RT and 3D-RT. Incidence rates were typically not provided. Heterogeneity in study characteristics, small study sizes and short follow-up times precluded multivariable modeling and pooling of data. In conclusion, among the first pediatric cohorts treated with 3D-RT, a broad variety of late toxicity is reported; precise estimates of incidence, and contributions of risk factors are unclear. Continued systematic evaluation of well-defined health outcomes in survivors treated with 3D-RT, including proton therapy, is needed to optimize evidence-based care for children with cancer and survivors.

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.

Yttrium-90 radioembolization in desmoplastic small round cell tumor with recurrent hepatic metastasis following hyperthermic intraperitoneal chemotherapy

We report a case of a 26-year-old male who was diagnosed with metastatic desmoplastic small round cell tumor initially treated with systemic chemotherapy followed by tumor debulking and hyperthermic intra-peritoneal chemotherapy. The patient was in complete remission by clinical and imaging criteria for 11 months, until he developed bi-lobar hepatic disease, which was successfully treated with selective internal radiation therapy by Yttrium-90. The patient demonstrated liver-specific complete response on follow-up imaging obtained 18 months after the procedure.

Multiagent chemotherapy including IrIVA regimen and maintenance therapy in the treatment of desmoplastic small round cell tumor

This study reports the treatment feasibility and efficacy of a novel multiagent intensive treatment program for young patients with desmoplastic small round cell tumor. This small series includes three patients and should be seen as a first suggestion of integration of the dose density and the maintenance chemotherapy concept. The IrIVA regimen (irinotecan, ifosfamide, vincristine, and actinomycin-D) is added-used at a short interval between chemotherapy administrations-at more classic intensive ifosfamide-based regimens. The vinorelbine and low-dose oral cyclophosphamide maintenance therapy is added at the end of conventional chemotherapy to achieve an antiangiogenic effect.

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.

Therapeutic Potential of NTRK3 Inhibition in Desmoplastic Small Round Cell Tumor

PURPOSE

Desmoplastic small round cell tumor (DSRCT) is a highly lethal intra-abdominal sarcoma of adolescents and young adults. DSRCT harbors a t(11;22)(p13:q12) that generates the EWSR1-WT1 chimeric transcription factor, the key oncogenic driver of DSRCT. EWSR1-WT1 rewires global gene expression networks and activates aberrant expression of targets that together mediate oncogenesis. EWSR1-WT1 also activates a neural gene expression program.

EXPERIMENTAL DESIGN

Among these neural markers, we found prominent expression of neurotrophic tyrosine kinase receptor 3 (NTRK3), a druggable receptor tyrosine kinase. We investigated the regulation of NTRK3 by EWSR1-WT1 and its potential as a therapeutic target in vitro and in vivo, the latter using novel patient-derived models of DSRCT.

RESULTS

We found that EWSR1-WT1 binds upstream of NTRK3 and activates its transcription. NTRK3 mRNA is highly expressed in DSRCT compared with other major chimeric transcription factor-driven sarcomas and most DSRCTs are strongly immunoreactive for NTRK3 protein. Remarkably, expression of NTRK3 kinase domain mRNA in DSRCT is also higher than in cancers with NTRK3 fusions. Abrogation of NTRK3 expression by RNAi silencing reduces growth of DSRCT cells and pharmacologic targeting of NTRK3 with entrectinib is effective in both in vitro and in vivo models of DSRCT.

CONCLUSIONS

Our results indicate that EWSR1-WT1 directly activates NTRK3 expression in DSRCT cells, which are dependent on its expression and activity for growth. Pharmacologic inhibition of NTRK3 by entrectinib significantly reduces growth of DSRCT cells both in vitro and in vivo, providing a rationale for clinical evaluation of NTRK3 as a therapeutic target in DSRCT.

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.

Desmoplastic Small Round Cell Tumor: Long-Term Complications After Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

Desmoplastic small round cell tumor (DSRCT) is a rare intra-abdominal soft tissue sarcoma affecting adolescents and young adults. Cytoreduction, hyperthermic intraperitoneal chemotherapy (CRS/HIPEC), and adjuvant radiotherapy may improve local control. We review our experience with patients who undergo CRS/HIPEC and adjuvant radiotherapy for DSRCT.

METHODS

A retrospective review was performed for patients with DSRCT from 2013 to 2017 who underwent CRS/HIPEC. Clinicopathologic, operative, and outcome data were reviewed.

RESULTS

Ten CRS/HIPEC procedures were performed for nine patients (7 males, 6 Caucasian, median age 19 years (range 10-24)). Four patients presented with extra-abdominal disease; five had liver involvement. The median peritoneal cancer index was 16 (range 5-20). All received neoadjuvant chemotherapy. CCR 0/1 resection was possible in nine patients. Major complications occurred in four with no operative mortalities. All received adjuvant chemotherapy, seven received radiation therapy, and three received stem-cell transplant. All but one patient recurred after treatment. The median recurrence-free and overall survival (OS) were 12 and 45 months (95% confidence interval 35.1-54.9) respectively, with a 3-year OS of 55%. Long-term parenteral nutrition was required in eight for a median of 261 days (range 37-997). Clinically significant long-term complications requiring further surgery included gastroparesis (N = 1), small bowel obstruction (N = 3) and hemorrhagic cystitis (N = 2).

CONCLUSIONS

Multimodal therapy for DSRCT consisting of multiagent neoadjuvant chemotherapy, CRS/HIPEC, adjuvant chemotherapy, and radiation therapy is associated with potential cumulative toxicity. Recurrence after resection is common. Prolonged parenteral nutrition may be necessary, and late gastrointestinal and genitourinary complications may require additional treatment.

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.

Whole abdominopelvic radiotherapy in desmoplastic small round cell tumour of abdomen: a challenge for radiation oncologists

An adolescent patient diagnosed with disseminated abdominal desmoplastic small round cell tumour (DSRCT) was taken up for systemic chemotherapy, debulking surgery, stem cell transplant followed by whole abdominopelvic radiotherapy using intensity-modulated radiotherapy. Following this, the patient developed multiple episodes of small bowel obstruction, a known complication of abdominal surgery and radiotherapy. The patient expired due to the complications of bowel obstruction 13 months after the completion of radiotherapy. Though we managed to achieve a complete response at the disease sites with an aggressive therapeutic approach, the patient eventually succumbed to treatment-induced morbidity. Large prospective trials to define management guidelines taking into account quality of life issues may not be feasible for a rare and aggressive scenario such as DSRCT. Therefore, case reports and series reporting not just the treatment techniques and survival, but also the resultant toxicities, will make us vigilant when choosing the intensity of its treatment.

Early experience with cytoreduction and hyperthermic intraperitoneal chemotherapy at a newly developed center for peritoneal malignancy

Background

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has improved outcomes for patients with peritoneal carcinomatosis (PC). We present our experience from a newly developed peritoneal surface malignancy program.

Methods

An IRB approved retrospective review was performed for the first 50 patients treated with CRS/HIPEC with clinicopathologic data described.

Results

Patients treated with CRS/HIPEC were Caucasian (64%), female (66%) with a median age of 53 years (range, 11-73 years). Primary pathology included: appendix (40%, n=20), ovary (20%, n=10), colon (14%, n=7), desmoplastic small round cell tumor (14%, n=7) or other (12%, n=6). The median peritoneal cancer index (PCI) score was 15.5 (range, 1-39) and 92% underwent complete cytoreduction (CCR 0/1). Median hospital length of stay was 9.0 days (range, 6-35 days). Eight patients (16%) suffered major morbidity with 2 (4%) 30-day mortalities.

Conclusions

Short-term outcomes observed after CRS/HIPEC in a newly developed center for PC are consistent with published higher volume center experiences.

Recurrent desmoplastic small round cell tumor responding to an mTOR inhibitor containing regimen

Desmoplastic small round cell tumor (DSRCT) is a rare mesenchymal tumor that typically presents with multiple abdominal masses. Initial treatment is multimodal in nature. Patients with relapsed DSRCT have a poor prognosis, and there are no standard therapies. We report our experience with five patients treated with vinorelbine, cyclophosphamide, and temsirolimus (VCT). Median number of VCT courses delivered was 7 (range 4-14 courses), and partial response was observed in all patients. Median time to progression or relapse was 8.5 months (range 7-16 months). Neutropenia and mucositis were most common toxicities (n = 4 each).

Desmoplastic Small Round Blue Cell Tumor: A Review of Treatment and Potential Therapeutic Genomic Alterations

Desmoplastic small round blue cell tumors (DSRCTs) originate from a cell with multilineage potential. A molecular hallmark of DSRCT is the EWS-WT1 reciprocal translocation. Ewing sarcoma and DSRCT are treated similarly due to similar oncogene activation pathways, and DSRCT has been represented in very limited numbers in sarcoma studies. Despite aggressive therapy, median survival ranges from 17 to 25 months, and 5-year survival rates remain around 15%, with higher survival reported among those undergoing removal of at least 90% of tumor in the absence of extraperitoneal metastasis. Almost 100% of these tumors contain t(11;22) (p13;q12) translocation, and it is likely that EWS-WT1 functions as a transcription factor possibly through WT1 targets. While there is no standard protocol for this aggressive disease, treatment usually includes the neoadjuvant HD P6 regimen (high-dose cyclophosphamide, doxorubicin, and vincristine (HD-CAV) alternating with ifosfamide and etoposide (IE) chemotherapy combined with aggressively attempted R0 resection). We aimed to review the molecular characteristics of DSRCTs to explore therapeutic opportunities for this extremely rare and aggressive cancer type.

Antiangiogenic effects in patients with progressive desmoplastic small round cell tumor: data from the French national registry dedicated to the use of off-labeled targeted therapy in sarcoma (OUTC's)

BACKGROUND

Desmoplastic small round cell tumor (DSRCT) is a very rare mesenchymal tumor that mainly affects teenagers and young adults with a mean age at diagnosis around 20-25 years. Although initial management still needs standardization, many centers will use multimodal treatment including intensive chemotherapy, extensive surgical resection followed by radiotherapy. Despite this, prognosis remains very poor and the median overall survival is 25 months. Recurrent disease is mainly treated by chemotherapy. Recently, due to the unmet medical need for recurrent disease, targeted therapies were explored for DSRCT.

METHODS

In this study, we assessed the response rate and progression free survival in nine cases of progressive DSRCT included in the OUTC's registry and treated with antiangiogenics targeted agents (sunitinib, sorafenib and bevacizumab). OUTC's, a French national registry, collects data about the use of off-label targeted therapy in sarcoma.

RESULTS

Eight males and one woman were included, with median age at diagnosis of 27.3 years (range from 9 to 48 years). They received a mean 3 lines (2-5) of treatment before antiangiogenic agent initiation. Six patients received sunitinib, two received sorafenib and one bevacizumab. Median progression free survival was 3.1 months (range 2-5.5 months) and best response observed was 5.5 months stable disease. Most patients had manageable low-grade toxicities, mainly fatigue, abdominal pain and skin toxicity.

CONCLUSIONS

Despite very limited activity of antiangiogenics in our study, prospective collection of cases of these rare tumors together with molecular data should guide therapeutic decision and enhance outcome.

Abdominal desmoplastic small round cell tumor without extraperitoneal metastases: Is there a benefit for HIPEC after macroscopically complete cytoreductive surgery?

Background

Desmoplastic Small Round Cell Tumor (DSRCT) is a rare disease affecting predominantly children and young adults and for which the benefit of hyperthermic intraperitoneal chemotherapy (HIPEC) after complete cytoreductive surgery (CCRS) remains unknown.

Methods

To identify patients with DSRCT without extraperitoneal metastases (EPM) who underwent CCRS between 1991 and 2015, a retrospective nation-wide survey was conducted by crossing the prospective and retrospective databases of the French Network for Rare Peritoneal Malignancies, French Reference Network in Sarcoma Pathology, French Sarcoma Clinical Network and French Pediatric Cancer Society.

Results

Among the 107 patients with DSRCT, 48 had no EPM and underwent CCRS. The median peritoneal cancer index (PCI) was 9 (range: 2–27). Among these 48 patients, 38 (79%) had pre- and/or postoperative chemotherapy and 23 (48%) postoperative whole abdominopelvic radiotherapy (WAP-RT). Intraperitoneal chemotherapy was administered to 11 patients (23%): two received early postoperative intraperitoneal chemotherapy (EPIC) and nine HIPEC. After a median follow-up of 30 months, the median overall survival (OS) of the entire cohort was 42 months. The 2-y and 5-y OS were 72% and 19%. The 2-y and 5-y disease-free survival (DFS) were 30% and 12%. WAP-RT was the only variable associated with longer peritoneal recurrence-free survival and DFS after CCRS. The influence of HIPEC/EPIC on OS and DFS was not statistically conclusive.

Conclusion

The benefit of HIPEC is still unknown and should be evaluated in a prospective trial. The value of postoperative WAP-RT seems to be confirmed.

Birth and evolution of the desmoplastic small round-cell tumor

The first large series of desmoplastic small round cell tumor was reported twenty-five years ago. This article reviews the original characterization of this neoplasm, and the eventual expansion of its clinical and pathological spectrum. Relevant data on its molecular features are summarized, in order to understand the search for therapeutic targets. The challenge ahead is to better know and cure this disease through the finding and validation of actionable therapeutic targets.

Role of Adjuvant Radiation Therapy After Surgery for Abdominal Desmoplastic Small Round Cell Tumors

PURPOSE

To identify the prognostic role of adjuvant abdominal radiation therapy (RT) on oncologic outcomes as a part of multimodal treatment in the management of desmoplastic small round cell tumor (DSRCT) and to determine its impact according to the quality of surgical resection.

METHODS AND MATERIALS

All patients treated for primary abdominal DSRCT in 8 French centers from 1991 to 2014 were included. Patients were retrospectively staged into 3 groups: group A treated with adjuvant RT after cytoreductive surgery, group B without RT after cytoreductive surgery, and group C by exclusive chemotherapy. Peritoneal progression-free survival (PPFS), progression-free survival (PFS), and overall survival (OS) were evaluated. We also performed a direct comparison between groups A and B to evaluate RT after cytoreductive surgery. Radiation therapy was also evaluated according to completeness of surgery: complete cytoreductive surgery (CCS) or incomplete cytoreductive surgery (ICS).

RESULTS

Thirty-seven (35.9%), thirty-six (34.9%), and thirty (28.0%) patients were included in groups A, B, and C, respectively. Three-year OS was 61.2% (range, 41.0%-76.0%), 37.6% (22.0%-53.1%), and 17.3% (6.3%-32.8%) for groups A, B, and C, respectively. Overall survival, PPFS, and PFS differed significantly among the 3 groups (P<.001, P<.001, and P<.001, respectively). Overall survival and PPFS were higher in group A (RT group) compared with group B (no RT group) (P=.045 and P=.006, respectively). Three-year PPFS was 23.8% (10.3%-40.4%) for group A and 12.51% (4.0%-26.2%) for group B. After CCS, RT improved PPFS (P=.024), but differences in OS and PFS were not significant (P=.40 and P=.30, respectively). After ICS, RT improved OS (P=.044). A trend of PPFS and PFS increase was observed, but the difference was not statistically significant (P=.073 and P=.076).

CONCLUSIONS

Adjuvant RT as part of multimodal treatment seems to confer oncologic benefits for patients treated for abdominal DSRCT after cytoreductive surgery and perioperative chemotherapy.

Desmoplastic small round cell tumor 20 years after its discovery

Desmoplastic small round cell tumor (DSRCT) was proposed as a distinct disease entity by William L Gerald and Juan Rosai in 1991. Over 850 patients have been reported in the medical literature. A specific translocation, t(11;22)(p13;q12), is seen in almost all cases, juxtaposing the EWS gene to the WT1 tumor suppressor gene. DSRCT is composed of nests of small round cells with polyphenotypic differentiation, typically a mixture of epithelial, mesenchymal and neural features, surrounded by a prominent desmoplastic stroma. DSRCT has a predilection for adolescent and young adult males, and primarily involves the abdominal cavity and pelvis. Survival is low despite their initial response to multimodal treatment. Most patients relapse with disseminated disease that is unresponsive to further therapy.

Survival and toxicity following sequential multimodality treatment including whole abdominopelvic radiotherapy for patients with desmoplastic small round cell tumor

BACKGROUND AND PURPOSE

Desmoplastic small round cell tumor (DSRCT) is a rare, aggressive malignancy. We report survival rates and toxicity associated with sequential multimodality treatment including whole abdominopelvic radiation therapy (WART).

MATERIAL AND METHODS

Medical records of 32 patients with DSRCT treated at our institution were reviewed. Patients underwent chemotherapy, cytoreductive surgery with hyperthermic intraperitoneal chemoperfusion (HIPEC), followed by WART with intensity-modulated radiation or volumetric-modulated arc therapy.

RESULTS

Median overall survival (OS) was 60months. After 18months of follow-up, 20 patients (62.5%) had disease recurrence and median disease-free survival (DFS) was 10months. Median time to extrahepatic abdominal failure was 19.4months. Factors affecting time to local progression included liver metastases at diagnosis, and an interval of greater than 5.6months between diagnosis and HIPEC or greater than 2.1months between HIPEC and WART. None of these factors altered OS. Grade 3 or higher toxicities occurred in 84% of patients.

CONCLUSIONS

WART following chemotherapy, surgical cytoreduction and HIPEC is an aggressive treatment for DSRCT patients and can result in severe side effects. Our median OS of 5years is favorable compared to prior studies, despite a median DFS of only 10months, which may be due to improved salvage therapies.

DESMOPLASTIC SMALL ROUND BLUE CELL TUMOUR OF THE ABDOMEN - A CASE REPORT

Desmoplastic Small Round Cell Tumour (DSRCT) is an uncommon malignant type of Small Round Blue Cell tumours with less than 200 cases reported in literature. Notorious for its aggressiveness, its commonest site of affectation is the abdomen, with a predilection for peritoneal cavity and prone to spread to multiple organs. We report a case of a 26-year old male undergraduate who presented with a 6-month history of progressive abdominal swelling associated with abdominal pain, weight loss, and change in bowel habits. He was cachectic with dyspnoea, bilateral pitting pedal oedema, a grossly distended and a palpable huge firm mass measuring 20 x 15cm. Immunohistochemisttry confirmed a diagnosis of DSRCT. An abdominopelvic Computed Tomography (CT) scan showed extensive abdominal and pelvic disease with pulmonary and liver metastases. He could only tolerate one course of chemotherapy due to deteriorating renal function. It ran an aggressive course of 9 months from onset of symptoms to eventual demise of the patient.

CONCLUSION

Desmoplastic Small Round Blue Cell Tumour is an uncommon and fatal disease, with no significant improvement in survival despite aggressive multimodality therapy. A high index of suspicion and Immunohistochemistry for accurate diagnosis as well as prompt and effective treatment will improve outcome.

Results of multimodal treatment for desmoplastic small round cell tumor of the abdomen and pelvis

PURPOSE

Desmoplastic small round cell tumor (DSRCT) is a rare aggressive malignancy that occurs in a young population with a male predominance. We studied the clinical and pathological characteristics of DSRCT and investigated the effects of multimodal therapy including aggressive surgical resection, induction chemotherapy, and external beam radiotherapy.

METHODS

We retrospectively reviewed and analyzed our experience with 11 histologically proven cases of DSRCT between March 2004 and October 2014. The clinical information, histological, immunohistochemistry and survival data of the patients were collected.

RESULTS

The median age at diagnosis was 31.4 years (range, 14-64 years) and nine (82%) of the patients were males. The most common presenting complaint was abdominal pain (72.7%). Surgical resection was attempted in five patients and included macroscopic total resection in two patients and debulking in three patients. Six patients underwent biopsy only. Eleven patients received multiagent chemotherapy. Five patients (45.5%) received radiotherapy. The median survival of patients who underwent surgical resection was 34.5 months, whereas the patients who underwent biopsy alone was 24.5 months (P<0.05). The median survival was 40.8 months in radiotherapy group, and 19.2 months in non-radiotherapy group (P<0.05). The 3-year progression-free survival rate was 27.2%. The median survival was 29 months, and the median time to local failure was 8.8 months. Cox regression analysis showed surgery and radiotherapy were highly significant in prolonging patients survival.

CONCLUSION

Multimodal therapy consists of combination of surgical resection, chemotherapy and radiotherapy results in improved survival in patients with DSRCT. For unresectable DSRCT, we recommend radiotherapy combined with anthracycline-based chemotherapy.

Incidence and outcomes of desmoplastic small round cell tumor: results from the surveillance, epidemiology, and end results database

Desmoplastic small round cell tumor (DSRCT) is a rare but highly fatal malignancy. Due to the rarity of this neoplasm, no large population based studies exist. Procedure. This is a retrospective cohort analysis. Incidence rates were calculated based on sex and ethnicity and compared statistically. Gender-, ethnicity-, and treatment- based survival were calculated using the Kaplan-Meier method. Results. A total of 192 cases of DSRCT were identified. Peak incidence age was between 20 and 24 years. Age-adjusted incidence rate for blacks was 0.5 cases/million and for whites was 0.2 cases/million (P = 0.037). There was no statistically significant difference in survival based on gender or ethnicity. When adjusted for age, there was no statistically significant difference in survival amongst patients who received radiation therapy compared to those who did not (HRadj = 0.73; 95% CI 0.49, 1.11). There was a statistically significant survival advantage for patients who received radiation after surgery compared to those who did not (HR 0.49; 95% CI 0.30, 0.79). Conclusion. DSRCT is more common in males and in people of African-American descent. Although overall survival remains poor, radiation therapy following surgery seems to improve outcome in these patients.

Trabectedin for desmoplastic small round cell tumours: a possible treatment option?

BACKGROUND

Desmoplastic small round cell tumour (DSRCT) is a rare sarcoma typically affecting young males and usually widely metastatic at presentation. Despite multimodal treatment approaches, the prognosis for DSRCT is extremely poor. Alkylator- and anthracyclines- based regimens are widely used as therapy and an initial response is common. Durable responses are exceptionally rare so further systemic treatment options for these patients represent an unmet medical need. We report two cases of metastatic, pretreated DSRCT patients achieving disease stabilisation with Trabectedin.

METHODS

Retrospective review of 2 patients with progressive DSRCT, treated with Trabectedin.

RESULTS

Two males aged 19 and 23 years treated with Trabectedin, 1.5 mg/m(2) over 24 hours 3 weekly for 6 and 5 cycles respectively. Best responses were stable disease in patient 1 and partial response (RECIST 1.1) in patient 2. Progression free survival was 4 months in both cases. Persistent neutropenia required 4 weekly administration in one patient but no other grade 3-4 toxicities occurred.

CONCLUSIONS

This report supports Trabectedin to be active and safe in pre-treated DSRCT patients. Further prospective and collaborative efforts are desirable to better define its role in the management of this disease.

Removal of an intra-abdominal desmoplastic small round cell tumor by repetitive debulking surgery: A case report and literature review

In the current study, a case of recurrent desmoplastic small round cell tumor (DSRCT) is presented, which was successfully treated by repetitive debulking surgery. In May 2010, a 39-year-old male, with a history of surgical resection of intra-abdominal DSRCT, visited the Ibaraki Medical Center, Tokyo Medical University Hospital (Ami, Japan) with severe lower abdominal discomfort. Abdominal computed tomography revealed a large tumor in the pouch of Douglas with a small number of nodules in the abdominal cavity. The recurrent DSRCT was diagnosed and removed via lower anterior resection; however, complete resection was impossible due to multiple peritoneal metastases. One year later, the patient developed pain in the right groin due to the growth of metastasized tumor cells in the groin lymph nodes. The affected lymph nodes were removed utilizing an extra-peritoneal approach. At the time of writing, the patient continues to survive without any symptoms 60 months since the initial surgery. In conclusion, surgical debulking is a significant procedure for relieving patient symptoms as well as improving the survival time of patients with metastatic and recurrent DSRCT.

Desmoplastic small round cell tumour: characteristics and prognostic factors of 41 patients and review of the literature

Background

Desmoplastic small round cell tumour (DSRCT) is a rare but frequently fatal sarcoma, and many of its characteristics still require further clarification.

Methods

We retrospectively analysed 41 patients treated at or referred to two regional referral centres in the UK between 1991 and 2012. A review of the current literature was also performed.

Results

The median age of presentation was 27 years (range 16 to 45 years), with a male-to-female ratio of 3:1. Ninety percent of patients had disease in the abdomen. The median size of the presenting tumour was 13 cm (range 3.5 to 23 cm), and 80% had metastatic disease at diagnosis, mainly in the liver (33%) and lungs (21%). Time-to-progression (TTP) was 3.9, 2.3 and 1.1 months after first-, second- and third-line chemotherapy, respectively. First-line treatment with VIDE chemotherapy appeared to confer the longest TTP (median 14.6 months). Ifosfamide and doxorubicin resulted in TTP of >3.8 months when used in any-line setting. Eleven patients received targeted agents as part of a clinical trial. After a median follow-up of 14 months, the overall median survival (MS) was 16 months. There was no difference in MS with regards to age, gender, or size of the presenting tumour. Patients with extra-abdominal disease survived longer compared to those with tumours in the abdomen (all still alive vs MS of 15 months; P = 0.0246). Patients with non-metastatic intra-abdominal disease who underwent surgery had an MS of 47 months (16 months for those who did not have surgery; P = 0.0235). Radiotherapy for locoregional control in patients with metastatic intra-abdominal DSRCT was associated with longer survival (MS of 47 vs 14 months; P = 0.0147).

Conclusions

DSRCT is a rare but often fatal disease that mainly affects younger male patients. Those with intra-abdominal DSRCT have a poorer prognosis, although surgical resection for localised disease and radiotherapy in the metastatic setting are associated with improved survival. A patient’s age, gender and size of presenting tumour do not have prognostic significance.

Desmoplastic small round cell tumour: the radiological, pathological and clinical features

OBJECTIVES

Desmoplastic small round cell tumours (DSRCTs) are rare aggressive tumours of young adults that present late and have poor prognosis. This review discusses distinctive radiological features, histopathology and clinical course of this soft-tissue sarcoma.

METHODS

From 1991 to 2012, the radiology of 20 patients with pathologically proven DSRCT was independently reviewed by two experienced radiologists. The clinical presentation, treatment and outcome were recorded.

RESULTS

PATIENTS

16 men, four women; mean age 28.3 years. Computed tomography (CT) demonstrated peritoneal/omental masses without an organ of origin (94 %), with the majority of cases demonstrating large (>5 cm) dominant soft-tissue deposit (80 %) with multiple smaller foci. CT and magnetic resonance imaging (MRI) typically demonstrated heterogeneous soft-tissue enhancement with cystic degeneration. A minority (20 %) demonstrated calcification. Lymph node enlargement occurred in 50 % of cases. Distant metastatic disease occurred in 25 %. Painful abdominal masses were clinically predominant. Treatment strategies include combination chemotherapy with debulking surgery and/or radiotherapy. Median survival from diagnosis was 22.8 months.

CONCLUSION

Features of multifocal peritoneal/omental masses, usually in combination with a dominant soft tissue deposit, are distinctive in this rare sarcoma. CT/MRI defines the extent of disease and characterises supporting imaging findings. Prolific desmoplastic reaction histologically separates DSRCT from similar subtypes. Combination treatment strategies can infer a survival benefit but prognosis remains poor. TEACHING POINTS : • DSRCTs are rare tumours of young adults (mean age 28.3 years) with a male predominance (4:1). • Painful abdominal masses clinically predominate. Non-specific features of malignancy can be present. • Multifocal peritoneal masses with a dominant soft tissue lesion is a distinctive imaging finding. • A large desmoplastic reaction differentiates DSRCTs from histologically similar round cell subtypes. • Despite debulking surgery with adjuvant chemotherapy, median survival from diagnosis is 22.3 months.

Reduced toxicity with intensity modulated radiation therapy (IMRT) for desmoplastic small round cell tumor (DSRCT): an update on the whole abdominopelvic radiation therapy (WAP-RT) experience

PURPOSE

Desmoplastic small round cell tumor (DSRCT) is a rare malignancy typically involving the peritoneum in young men. Whole abdominopelvic radiation therapy (WAP-RT) using conventional 2-dimensional (2D) radiation therapy (RT) is used to address local recurrence but has been limited by toxicity. Our objectives were to assess the benefit of intensity modulated radiation therapy (IMRT) on toxicity and to update the largest series on radiation for DSRCT.

METHODS AND MATERIALS

The records of 31 patients with DSRCT treated with WAP-RT (22 with 2D-RT and 9 with IMRT) between 1992 and 2011 were retrospectively reviewed. All received multi-agent chemotherapy and maximal surgical debulking followed by 30 Gy of WAP-RT. A further focal boost of 12 to 24 Gy was used in 12 cases. Boost RT and autologous stem cell transplantation were nearly exclusive to patients treated with 2D-RT. Toxicities were assessed with the Common Terminology Criteria for Adverse Events. Dosimetric analysis compared IMRT and simulated 2D-RT dose distributions.

RESULTS

Of 31 patients, 30 completed WAP-RT, with a median follow-up after RT of 19 months. Acute toxicity was reduced with IMRT versus 2D-RT: P=.04 for gastrointestinal toxicity of grade 2 or higher (33% vs 77%); P=.02 for grade 4 hematologic toxicity (33% vs 86%); P=.01 for rates of granulocyte colony-stimulating factor; and P=.04 for rates of platelet transfusion. Post treatment red blood cell and platelet transfusion rates were also reduced (P=.01). IMRT improved target homogeneity ([D05-D95]/D05 of 21% vs 46%) and resulted in a 21% mean bone dose reduction. Small bowel obstruction was the most common late toxicity (23% overall). Updated 3-year overall survival and progression-free survival rates were 50% and 24%, respectively. Overall survival was associated with distant metastasis at diagnosis on multivariate analysis. Most failures remained intraperitoneal (88%).

CONCLUSIONS

IMRT for consolidative WAP-RT in DSRCT improves hematologic toxicity in particular. Although the long-term efficacy of current treatment options remains disappointing, the improved therapeutic index of IMRT may aid in generalizing its use and allowing the addition of novel approaches such as intraperitoneal immunotherapy.

Advantages of whole-liver intensity modulated radiation therapy in children with Wilms tumor and liver metastasis

PURPOSE

To demonstrate the dosimetric advantages of intensity modulated radiation therapy (IMRT) in children with Wilms tumor (WT) undergoing whole-liver (WL) RT.

METHODS AND MATERIALS

Computed tomography simulation scans of 10 children, either 3 (3D) or 4-dimensional (4D), were used for this study. The WL PTV was determined by the 3D or 4D liver volumes, with a margin of 1 cm. A total of 40 WL RT plans were performed: 10 each for left- and right-sided WT with IMRT and anteroposterior-posteroanterior (AP-PA) techniques. The radiation dose-volume coverage of the WL planning target volume (PTV), remaining kidney, and other organs were analyzed and compared.

RESULTS

The 95% dose coverage to WL PTV for left and right WT were as follows: 97% ± 4% (IMRT), 83% ± 8% (AP-PA) (P<.01) and 99% ± 1% (IMRT), 94% ± 5% (AP-PA) (P<.01), respectively. When 3D WL PTV was used for RT planning, the AP-PA technique delivered 95% of dose to only 78% ± 13% and 88% ± 8% of 4D liver volume. For left WT, the right kidney V15 and V10 for IMRT were 29% ± 7% and 55% ± 8%, compared with 61% ± 29% (P<.01) and 78% ± 25% (P<.01) with AP-PA. For right WT, the left kidney V15 and V10 were 0 ± 0 and 2% ± 3% for IMRT, compared with 25% ± 19% (P<.01) and 40% ± 31% (P<.01) for AP-PA.

CONCLUSIONS

The use of IMRT and 4D treatment planning resulted in the delivery of a higher RT dose to the liver compared with the standard AP-PA technique. Whole-liver IMRT also delivered a significantly lower dose to the remaining kidney.

Desmoplastic small round cell tumor: current management and recent findings

Desmoplastic small round cell tumor (DSRCT) is a rare and highly aggressive mesenchymal tumor that develops in the abdominal cavity of young men adults. Patients typically present with symptoms of abdominal sarcomatosis. Diagnosis is based on histological analysis of biopsies which typically show small round blue cells in nests separated by an abundant desmoplastic stroma. DSRCT is associated with a unique chromosomal translocation t(11:22) (p 13; q 12) that involves the EWSR1 and WT1 genes. The prognosis is particularly poor; median survival ranges from 17 to 25 months, largely due to the presentation of the majority of patients with metastatic disease. Management of DSRCT remains challenging and current schemes lack a significant cure rate despite the use of aggressive treatments such as polychemotherapy, debulking surgery and whole abdominal radiation. Several methods are being evaluated to improve survival: addition of chemotherapy and targeted therapies to standard neoadjuvant protocol, completion of surgical resection with HIPEC, postoperative IMRT, treatment of hepatic metastases with [(90)Y]Yttrium microsphere liver embolization.