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

Kidney Disease in Childhood Cancer Survivors Treated With Radiation Therapy: A PENTEC Comprehensive Review

PURPOSE

Kidney injury is a known late and potentially devastating complication of abdominal radiation therapy (RT) in pediatric patients. A comprehensive Pediatric Normal Tissue Effects in the Clinic review by the Genitourinary (GU) Task Force aimed to describe RT dose-volume relationships for GU dysfunction, including kidney, bladder, and hypertension, for pediatric malignancies. The effect of chemotherapy was also considered.

METHODS AND MATERIALS

We conducted a comprehensive PubMed search of peer-reviewed manuscripts published from 1990 to 2017 for investigations on RT-associated GU toxicities in children treated for cancer. We retrieved 3271 articles with 100 fulfilling criteria for full review, 24 with RT dose data and 13 adequate for modeling. Endpoints were heterogenous and grouped according to National Kidney Foundation: grade ≥1, grade ≥2, and grade ≥3. We modeled whole kidney exposure from total body irradiation (TBI) for hematopoietic stem cell transplant and whole abdominal irradiation (WAI) for patients with Wilms tumor. Partial kidney tolerance was modeled from a single publication from 2021 after the comprehensive review revealed no usable partial kidney data. Inadequate data existed for analysis of bladder RT-associated toxicities.

RESULTS

The 13 reports with long-term GU outcomes suitable for modeling included 4 on WAI for Wilms tumor, 8 on TBI, and 1 for partial renal RT exposure. These reports evaluated a total of 1191 pediatric patients, including: WAI 86, TBI 666, and 439 partial kidney. The age range at the time of RT was 1 month to 18 years with medians of 2 to 11 years in the various reports. In our whole kidney analysis we were unable to include chemotherapy because of the heterogeneity of regimens and paucity of data. Age-specific toxicity data were also unavailable. Wilms studies occurred from 1968 to 2011 with mean follow-ups 8 to 15 years. TBI studies occurred from 1969 to 2004 with mean follow-ups of 4 months to 16 years. We modeled risk of dysfunction by RT dose and grade of toxicity. Normal tissue complication rates ≥5%, expressed as equivalent doses, 2 Gy/fx for whole kidney exposures occurred at 8.5, 10.2, and 14.5 Gy for National Kidney Foundation grades ≥1, ≥2, and ≥3, respectively. Conventional Wilms WAI of 10.5 Gy in 6 fx had risks of ≥grade 2 toxicity 4% and ≥grade 3 toxicity 1%. For fractionated 12 Gy TBI, those risks were 8% and <3%, respectively. Data did not support whole kidney modeling with chemotherapy. Partial kidney modeling from 439 survivors who received RT (median age, 7.3 years) demonstrated 5 or 10 Gy to 100% kidney gave a <5% risk of grades 3 to 5 toxicity with 1500 mg/m2 carboplatin or no chemo. With 480 mg/m2 cisplatin, a 3% risk of ≥grade 3 toxicity occurred without RT and a 5% risk when 26% kidney received ≥10 Gy. With 63 g/m2 of ifosfamide, a 5% risk of ≥grade 3 toxicity occurred with no RT, and a 10% toxicity risk occurred when 42% kidney received ≥10 Gy.

CONCLUSIONS

In patients with Wilms tumor, the risk of toxicity from 10.5 Gy of WAI is low. For 12 Gy fractionated TBI with various mixtures of chemotherapy, the risk of severe toxicity is low, but low-grade toxicity is not uncommon. Partial kidney data are limited and toxicity is associated heavily with the use of nephrotoxic chemotherapeutic agents. Our efforts demonstrate the need for improved data gathering, systematic follow-up, and reporting in future clinical studies. Current radiation dose used for Wilms tumor and TBI appear to be safe; however, efforts in effective kidney-sparing TBI and WAI regimens may reduce the risks of renal injury without compromising cure.

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.

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.

Intra-Abdominal Desmoplastic Small Round Cell Tumor (DSRCT) and the Role of Hyperthermic Intraperitoneal Chemotherapy (HIPEC): A Review

Desmoplastic small round cell tumor is a very rare and highly aggressive soft tissue sarcoma, usually presenting with multiple intra-abdominal tumors in young males. Patients present with advanced disease and the overall survival is dismal. Multiple studies report relatively favorable outcomes with multimodal treatment consisting of chemotherapy, surgery and radiotherapy. If resection is feasible, complete cytoreductive surgery is the cornerstone of surgical treatment. The benefit of hyperthermic intraperitoneal chemotherapy in addition to cytoreductive surgery is unclear, and few studies have evaluated this option. We sought to identify the role of hyperthermic intraperitoneal chemotherapy in patients with intra-abdominal desmoplastic small round cell tumor. Our review of the available literature revealed no clear survival benefit in performing hyperthermic intraperitoneal chemotherapy after cytoreductive surgery.

Advances in the treatment of pediatric solid tumors: A 50-year perspective

In the United States, more than 10 000 cancers occur annually in children aged 0-14 years, and more than 5000 in adolescents aged 15-19. In the last 50 years, significant advances have been made in imaging, molecular pathology, stage and risk assessment, surgical approach, multidisciplinary treatment, and survival for pediatric solid tumors (particularly neuroblastoma, Wilms tumor, rhabdomyosarcoma, and hepatoblastoma). Moreover, the molecular driver for fibrolamellar hepatocellular carcinoma, which occurs in adolescence and young adulthood, has been identified.

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

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

Trabectedin-irinotecan, a potentially promising combination in relapsed desmoplastic small round cell tumor: report of two cases

Effective new drugs are urgently needed for desmoplastic small round cell tumor (DSRCT), an extremely rare and aggressive disease with a generally poor prognosis. We describe two heavily-pretreated young patients with advanced-stage DSRCT given third-line treatment with a combination of trabectedin and irinotecan, based on our preclinical data demonstrating its effect on patient-derived xenografts. This trabectedin-irinotecan treatment showed a limited toxicity. One patient had a mixed response (overall stable disease), the other a complete tumor remission. This is the first report of preliminary findings to suggest that combining trabectedin and irinotecan is worth further investigating as a potentially valuable chemotherapy for DSRCT.

Immunotherapy and Radioimmunotherapy for Desmoplastic Small Round Cell Tumor

Desmoplastic small round cell tumor (DRSCT) is a highly aggressive primitive sarcoma that primarily affects adolescent and young adult males. The 5-year survival rate is 15-30% and few curative treatment options exist. Although there is no standard treatment for DSRCT, patients are most often treated with a combination of aggressive chemotherapy, radiation, and surgery. Targeted therapy inhibitors of PDGFA and IGF-1R, which are almost uniformly overexpressed in DSRCT, have largely failed in clinical trials. As in cancer in general, interest in immunotherapy to treat DSRCT has increased in recent years. To that end, several types of immunotherapy are now being tested clinically, including monoclonal antibodies, radionuclide-conjugated antibodies, chimeric antigen receptor T cells, checkpoint inhibitors, and bispecific antibodies (BsAbs). These types of therapies may be particularly useful in DSRCT, which is frequently characterized by widespread intraperitoneal implants, which are difficult to completely remove surgically and are the frequent cause of relapse. Successful treatment with immunotherapy or radioimmunotherapy following debulking surgery could eradiate these micrometasteses and prevent relapse. Although there has been limited success to date for immunotherapy in pediatric solid tumors, the significant improvements in survival seen in the treatment of other pediatric solid tumors, such as metastatic neuroblastoma and its CNS spread, suggest a potential of immunotherapy and specifically compartmental immunotherapy in DSRCT.

A Classic Presentation of Desmoplastic Small Round Cell Tumor

Desmoplastic small round cell tumor (DSRCT) is a rare malignancy, of uncertain differentiation, which more commonly affects adolescents and young adult males; it usually has an intra-abdominal location. We describe the case of a 35-year-old male who presented initially with occasional abdominal pain, and subsequently with abdominal mass sensation, without any other associated symptoms. Imaging studies reported an intra-abdominal mass located in mesogastrium, right hypochondrium, and right lumbar region, without clear evidence of infiltration to secondary structures, but with clear peritoneal spread to greater omentum and pelvis. Definitive diagnosis of DSRCT is based on histologic and immunohistochemical findings. Standard treatment includes intensive neoadjuvant chemotherapy, surgical cytoreduction, and radiotherapy. Despite this multidisciplinary approach, DSRCT has a poor prognosis and a high mortality rate at five years.

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.

Uncommon and peculiar soft tissue sarcomas: Multidisciplinary review and practical recommendations. Spanish Group for Sarcoma research (GEIS -GROUP). Part II

Among all Soft Tissue sarcomas there are some subtypes with low incidence and/or peculiar clinical behaviour, that need to be consider separately. Most of them are orphan diseases, whose biological characteristics imply a clearly different diagnostic and therapeutic approach from other more common sarcoma tumors. We present a brief and updated multidiciplinary review, focused on practical issues, aimed at helping clinicians in decision making. In this second part we review these subtypes: Alveolar Soft Part Sarcoma, Epithelioid Sarcoma, Clear Cell Sarcoma, Desmoplastic Small Round Cell Tumor, Rhabdoid Tumor, Phyllodes Tumor, Tenosynovial Giant Cell Tumors, Myoepithelial Tumor, Perivascular Epithelioid Cell Neoplasms (PEComas), Extraskeletal Myxoid Chondrosarcoma, NTRK-fusions Sarcomas. Most of them present their own radiological and histopathological feautures, that are essential to know in order to achieve early diagnosis. In some of them, molecular diagnosis is mandatory, not only in the diagnosis, but also to plan the treatment. On the other hand, and despite the low incidence, a great scientific research effort has been made to achieve new treatment opportunities for these patients even with approved indications. These include new treatments with targeted therapies and immunotherapy, which today represent possible therapeutic options. It is especially important to be attentive to new and potential avenues of research, and to promote the conduct of specific clinical trials for rare sarcomas.

Comprehensive Molecular Profiling of Desmoplastic Small Round Cell Tumor

Desmoplastic small round cell tumor (DSRCT) is characterized by the EWSR1-WT1 t(11;22) (p13:q12) translocation. Few additional putative drivers have been identified, and research has suffered from a lack of model systems. Next-generation sequencing (NGS) data from 68 matched tumor-normal samples, whole-genome sequencing data from 10 samples, transcriptomic and affymetrix array data, and a bank of DSRCT patient-derived xenograft (PDX) are presented. EWSR1-WT1 fusions were noted to be simple, balanced events. Recurrent mutations were uncommon, but were noted in TERT (3%), ARID1A (6%), HRAS (5%), and TP53 (3%), and recurrent loss of heterozygosity (LOH) at 11p, 11q, and 16q was identified in 18%, 22%, and 34% of samples, respectively. Comparison of tumor-normal matched versus unmatched analysis suggests overcalling of somatic mutations in prior publications of DSRCT NGS data. Alterations in fibroblast growth factor receptor 4 (FGFR4) were identified in 5 of 68 (7%) of tumor samples, whereas differential overexpression of FGFR4 was confirmed orthogonally using 2 platforms. PDX models harbored the pathognomic EWSR1-WT1 fusion and were highly representative of corresponding tumors. Our analyses confirm DSRCT as a genomically quiet cancer defined by the balanced translocation, t(11;22)(p13:q12), characterized by a paucity of secondary mutations but a significant number of copy number alterations. Against this genomically quiet background, recurrent activating alterations of FGFR4 stood out, and suggest that this receptor tyrosine kinase, also noted to be highly expressed in DSRCT, should be further investigated. Future studies of DSRCT biology and preclinical therapeutic strategies should benefit from the PDX models characterized in this study. IMPLICATIONS: These data describe the general quiescence of the desmoplastic small round cell tumor (DSRCT) genome, present the first available bank of DSRCT model systems, and nominate FGFR4 as a key receptor tyrosine kinase in DSRCT, based on high expression, recurrent amplification, and recurrent activating mutations.

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.

Mesenchymal Stem Cells for Mitigating Radiotherapy Side Effects

Radiation therapy for cancers also damages healthy cells and causes side effects. Depending on the dosage and exposure region, radiotherapy may induce severe and irreversible injuries to various tissues or organs, especially the skin, intestine, brain, lung, liver, and heart. Therefore, promising treatment strategies to mitigate radiation injury is in pressing need. Recently, stem cell-based therapy generates great attention in clinical care. Among these, mesenchymal stem cells are extensively applied because it is easy to access and capable of mesodermal differentiation, immunomodulation, and paracrine secretion. Here, we summarize the current attempts and discuss the future perspectives about mesenchymal stem cells (MSCs) for mitigating radiotherapy side effects.

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.

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.

B7H3-Directed Intraperitoneal Radioimmunotherapy With Radioiodinated Omburtamab for Desmoplastic Small Round Cell Tumor and Other Peritoneal Tumors: Results of a Phase I Study

PURPOSE

Desmoplastic small round cell tumor (DSRCT), a rare sarcoma of adolescents/young adults primarily involving the peritoneum, has a long-term survival of < 20% despite aggressive multimodality treatment. B7H3 is expressed on DSRCT cell surface, providing a target for antibody-based immunotherapy.

PATIENTS AND METHODS

In this phase I study, we evaluated the safety, pharmacokinetics, and biodistribution of intraperitoneal (IP) radioimmunotherapy (RIT) with the anti-B7H3 murine monoclonal antibody ¹³¹I-omburtamab in patients with DSRCT or other B7H3-expressing tumors involving the peritoneum. After thyroid blockade, patients received ¹³¹I-omburtamab as a single IP injection at escalated activities from 1.11 to 3.33/GBq/m². A prior tracer dose of IP 74 MBq¹²⁴I-omburtamab was used for radioimmuno-positron emission tomography imaging. Each injection was followed by IP saline infusion.

RESULTS

Fifty-two patients (48, three, and one with DSRCT, peritoneal rhabdomyosarcoma, and Ewing sarcoma, respectively) received IP ¹³¹I-omburtamab administered on an outpatient basis. Maximum tolerated dose was not reached; there were no dose-limiting toxicities. Major related adverse events were transient: grade 4 neutropenia (n = 2 patients) and thrombocytopenia (n = 1), and grade 1 (10%) and grade 2 (52%) pain lasting < 2 hours related to saline infusion. Hypothyroidism was not observed, and antidrug antibody was elicited in 5%. Mean (± SD) projected peritoneal residence time was 22.4 ± 7.9 hours. Mean projected absorbed doses for ¹³¹I-omburtamab based on ¹²⁴I-omburtamab dosimetry to normal organs were low and well within tolerable limits. More than 80% ¹³¹I remained protein bound in blood 66 hours after RIT. On the basis of peritoneal dose and feasibility for outpatient administration, the recommended phase II activity was established at 2.96 GBq/m². Patients with DSRCT receiving standard whole-abdominal radiotherapy after RIT did not experience unexpected toxicity.

CONCLUSION

IP RIT ¹³¹I-omburtamab was well tolerated with minimal toxicities. Radiation exposure to normal organs was low, making combination therapy with other anticancer therapies feasible.

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.

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.

Whole abdominopelvic intensity-modulated radiation therapy for peritoneal disseminated rhabdomyosarcoma with three-year follow-up: a case report

Background

The role of local radiotherapy in the treatment of metastatic rhabdomyosarcoma is important. However, with peritoneal dissemination, the application of local therapy is challenging. Although there are few reports addressing the efficacy of the whole abdominopelvic irradiation to peritoneal disseminated rhabdomyosarcoma patients, no precise curse of treatment nor the follow up result is explained in paper nor in the text.

Case presentation

Six years old rhabdomyosarcoma boy with peritoneal dissemination was treated at our facility under COG D9803 protocol (vincristine, dactinomycin, and cyclophosphamide (VAC)). He underwent tumor resection on the 14th week according to the protocol. During surgery, the 2-cm residual tumor was completely resected, but in the pelvis, numerous nodules that were suspected as peritoneal disseminated tumors were observed. We administered 30 Gy/20fr whole abdominopelvic radiotherapy using volumetric modulated arc therapy (VMAT) technique and a 6 Gy sequential boost to pelvis after the surgery and completed the protocol treatment. During the course of treatment, the patient experienced G4 hematological toxicity and received multiple transfusions, particularly after whole abdominopelvic irradiation. He has achieved complete remission and is alive without evidence of recurrence and severe late adverse effect for 3 years. In terms of growth, his height and weight are within the average values for Japanese boys at the same age.

Conclusion

By using the VMAT technique, a patient with peritoneal disseminated rhabdomyosarcoma can be treated, and a dose of 30 Gy to the whole abdominopelvis with concurrent chemotherapy may be tolerable.

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.

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.

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.

Utilization pattern and survival outcomes of adjuvant therapies in high-grade nonretroperitoneal abdominal soft tissue sarcoma: A population-based study

BACKGROUND

Nonretroperitoneal abdominal soft tissue sarcoma (NRA-STS) is a rare disease with limited data supporting its management. Our study aimed to reveal the utilization patterns of adjuvant therapy and its potential survival benefits using the National Cancer Data Base.

MATERIALS

The analysis included patients with resected high-grade NRA-STS. Chi-square analysis was used to evaluate distribution of patient and tumor-related factors within treatment groups. The Kaplan-Meier and Cox proportional hazards model were utilized to evaluate overall survival according to treatment approach. Multivariate analysis was used to determine the impact of these factors on patients' outcome. Matched propensity score analysis was implemented to control for imbalance of confounding variables.

RESULTS

At median follow-up of 49 months, 5-year overall survival improved from 46% without adjuvant radiation therapy to 52% (P = 0.009) with radiotherapy delivery with a 30% reduction in hazard of death (95% confidence interval = 0.58-0.84). On multivariate analysis, age <50, tumor <8 cm, negative margins and radiotherapy delivery were significant predictors of improved survival. Chemotherapy was not associated with significant survival improvement (Hazard Ratios [HR]: 0.89, P = 0.28).

CONCLUSION

Adjuvant radiotherapy was associated with improved survival in high-grade NRA-STS. Chemotherapy was not associated with a survival improvement; however, further studies are needed to refine treatment strategies.

Radiation Dose to the Thoracic Vertebral Bodies Is Associated With Acute Hematologic Toxicities in Patients Receiving Concurrent Chemoradiation for Lung Cancer: Results of a Single-Center Retrospective Analysis

PURPOSE

To test the hypothesis that increasing radiation therapy (RT) dose to the thoracic vertebral bodies (TVBs) contributes to the development of hematologic toxicities (HTs) in patients with lung cancer.

METHODS AND MATERIALS

Cases of non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) treated with definitive chemoradiation with concurrent platinum-based doublet chemotherapy at our institution from 2007 to 2016 were identified. Mean TVB dose and the volume of TVBs receiving at least 5 to 60 Gy (V₅-V₆₀) were retrospectively recorded. Logistic regression was used to test associations between grade ≥3 HT (HT3+) and dosimetric/clinical parameters. Normal tissue complication probability was evaluated using the Lyman-Kutcher-Burman (LKB) model for HT3+, and receiver operating characteristics analysis was used to determine dosimetric cut-points.

RESULTS

We identified 201 patients, the majority having NSCLC (n=162, 81%) and stage III to IV disease (n=179, 89%). All patients received either cisplatin/etoposide (n=107, 53%) or carboplatin/paclitaxel (n=94, 47%). Median RT dose was 60 Gy (range, 60-70 Gy). The rate of HT3+ was 49% (n=99). Increasing mean TVB dose (per Gy) was associated with higher odds of developing HT3+ (odds ratio 1.041, 95% confidence interval 1.004-1.080, P=.032), as were increasing TVB V₅ to V₂₀. These dosimetric correlates to HT3+ persisted on multivariate analysis. Constrained optimization of the LKB model for HT3+ yielded the parameters: n=1, m=1.79, and TD₅₀=21.4 Gy. Optimal cut-points identified were V₅=65%, V₁₀=60%, V₂₀=50%, and mean dose=23.5 Gy. Patients with values above these cut-points had an approximately 2-fold increased risk of HT3+.

CONCLUSIONS

We found that mean TVB dose and low-dose parameters (V₅-V₂₀) were associated with HT3+ in chemoradiation for lung cancer. Per the LKB model, bone marrow behaves like a parallel organ (n=1), implying that mean TVB dose is a useful predictor for toxicity. These data suggest that efforts to spare dose to the TVBs may reduce rates of severe HT.

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.

Plasma DNA-based molecular diagnosis, prognostication, and monitoring of patients with EWSR1 fusion-positive sarcomas

Purpose

Ewing Sarcoma (ES) and Desmoplastic Small Round Cell Tumors (DSRCT) are aggressive sarcomas molecularly characterized by EWSR1 gene fusions. As pathognomonic genomic events in these respective tumor types, EWSR1 fusions represent robust potential biomarkers for disease monitoring.

Patients and Methods

To investigate the feasibility of identifying EWSR1 fusions in plasma derived cell-free DNA (cfDNA) from ES and DSRCT patients, we evaluated two complementary approaches in samples from 17 patients with radiographic evidence of disease. The first approach involved identification of patient-specific genomic EWSR1 fusion breakpoints in formalin-fixed, paraffin-embedded tumor DNA using a broad, hybridization capture-based next generation sequencing (NGS) panel, followed by design of patient-specific droplet digital PCR (ddPCR) assays for plasma cfDNA interrogation . The second approach employed a disease-tailored targeted hybridization capture-based NGS panel applied directly to cfDNA which included EWSR1 as well as several other genes with potential prognostic utility.

Results

EWSR1 fusions were identified in 11/11 (100%) ES and 5/6 (83%) DSRCT samples by ddPCR, while 10/11 (91%) and 4/6 (67%) were identified by NGS. The ddPCR approach had higher sensitivity, ranging between 0.009-0.018% sensitivity. However, the hybrid capture-based NGS assay identified the precise fusion breakpoints in the majority of cfDNA samples, as well as mutations in TP53 and STAG2, two other recurrent, clinically significant alterations in ES, all without prior knowledge of the tumor sequencing results.

Conclusion

These results provide a compelling rationale for an integrated approach utilizing both NGS and ddPCR for plasma cfDNA-based biomarker evaluations in prospective cooperative group studies.

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.

Desmoplastic Small Round Cell Tumor

Desmoplastic small round cell tumor (DSRCT) is an aggressive small round cell neoplasm which predominantly occurs intra-abdominally in adolescents and young adults with a male predominance, and which is characterized by a recurrent t(11;22)(p13;q12) translocation leading to formation of the EWSR1-WT1 fusion gene, which generates a chimeric protein with transcriptional regulatory activity. Histologically, DSRCT has a characteristic morphology, of islands of monotonous small cells within prominent sparsely cellular fibroblastic stroma, and immunohistochemically it shows polyphenotypic multidirectional differentiation, with expression of epithelial, muscle, and neural markers. However, DSRCT can arise more rarely in other sites and exhibit a spectrum of both histologic features and immunoprofile, which may confuse diagnosis with other small round cell neoplasms. Correct diagnosis is important to ensure correct treatment and prognostication; DSRCT are almost universally fatal neoplasms with patients usually succumbing to disease within the first 2 years of diagnosis. While combination treatment strategies can confer a survival benefit, the overall prognosis remains poor. Further insight into the tumorigenic molecular changes generated by the fusion oncogene may lead to the generation of specific targeted therapies. We review DSRCT, discussing morphology and immunohistochemistry, molecular genetic findings, potential targeted treatments, and the differential diagnosis.

Management of desmoplastic small round cell tumor

Desmoplastic small round cell tumor (DSRCT) is a soft tissue sarcoma of mesenchymal cell origin that typically presents with multiple intra-abdominal tumors and exhibits a multi-phenotypic pattern of immunohistochemical staining. The specific organ or tissue type of origin has yet to be identified. DSRCT rarely arises as a singular tumor in the abdomen; in most cases, there are dozens to hundreds of abdominal peritoneal tumors that are detected on diagnosis. One very large dominant mass is usually present in the omentum, with an additional one or two large conglomerates of tumors in the pelvis and right peritoneum, respectively. Despite an often overwhelmingly large number of abdominal tumors, symptoms of bowel obstruction are rare. Ascites may be present. In late stages, pleural effusions, pleural implants, mediastinal adenopathy, supraclavicular adenopathy, or bone metastasis may be present. With this challenging disease, multidisciplinary therapy, including aggressive surgery, is warranted. This review will address DSRCT biology and treatment options and discuss outcomes.

Dosimetric predictors of acute haematological toxicity in oesophageal cancer patients treated with neoadjuvant chemoradiotherapy

OBJECTIVE

Haematological toxicity (HT) is common in patients with oesophageal cancer (EC) treated with chemoradiotherapy (CRT). The Quantitative Analysis of Normal Tissue Effects in the Clinic guidelines provide no dose constraints for the bone marrow (BM) to avoid HT. We aimed to determine dosimetric factors associated with HT during CRT for EC.

METHODS

41 patients with EC treated with neoadjuvant cisplatin and 5-fluorouracil-based CRT were retrospectively reviewed. Associations between the dose-volume histogram parameters of thoracic bones and blood cell count changes during CRT were assessed using logistic regression analyses. Receiver-operating characteristic curves were used to derive optimal dosimetric planning constraints. Vx indicates the total organ volume percentage exceeding a radiation dose of x (Gy).

RESULTS

Greater thoracic vertebrae and rib irradiation doses, including mean vertebral dose (MVD), thoracic vertebrae V5-30 (TVV5-30), mean rib dose and rib V5-20, were associated with increased leukopenia (grade ≥ 3) risk. Additional BM sites (sternum, scapulae and clavicles) did not influence HT. White blood cell and absolute neutrophil count nadirs were associated with increased irradiation doses to the thoracic vertebrae, ribs and sternum. Chemotherapy cycle number was not significantly associated with severe neutropenia or leukopenia. Cut-off values with the highest likelihood of avoiding leukopenia were MVD < 25.9 Gy, TVV20 < 70% and TVV10 < 77%.

CONCLUSION

Thoracic bone irradiation dose was significantly associated with HT after adjusting for chemotherapy effects. Efforts to maintain MVD < 25.9 Gy, TVV10 < 77% and TVV20 < 70% could reduce HT.

ADVANCES IN KNOWLEDGE

This is the first study addressing issues concerning HT in patients with neoadjuvant CRT-treated EC.

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.

Clinical Characteristics and Outcomes of Pediatric Patients with Desmoplastic Small Round Cell Tumor

Desmoplastic small round cell tumor (DSRCT) is a rare malignancy that typically affects pediatric and young adult patients. There are limited data on the clinical features of pediatric DSRCT. We selected patients aged 0-21 years reported to the Surveillance, Epidemiology and End Results Program from 1991-2011. We estimated overall survival using Kaplan-Meier approaches and compared outcomes using the log rank test. The median age of the 95 pediatric patients was 15.3 years (range: 0-21). The majority of tumors originated in the abdomen and pelvis (84.4%) and the majority of patients had distant metastasis (72.6%). A minority of patients received radiation (34%). Overall survival at 5 years was poor (18.1%; 95% confidence interval 10.1-27.9%). Radiation therapy was associated with superior survival. Pediatric patients with DSRCT have significant disease burden. Outcomes for children are poor, though patients selected for radiation appear to have improved survival.

Complete response of giant desmoplastic small round cell tumor treated with chemoradiotherapy: A case report

Desmoplastic small round cell tumor (DSRCT) is a rare tumor that mainly affects adolescents, and typically involves the abdominal and pelvic peritoneum. The present study reports one case of giant DSRCT, treated with concurrent chemoradiotherapy, and reviews the available medical literature. A 38-year-old man presented with a 3-month history of pain in the left lower abdomen and nausea, associated with decreased appetite and weight loss. Computed tomography (CT) showed a 12.3×7.9 cm confluent solid mass in the lower abdomen and pelvic cavity. The patient underwent exploratory laparotomy and the final pathological diagnosis was DSRCT. Following laparotomy, the patient was treated with external beam radiotherapy to the whole abdomen and pelvis to a dose of 40 Gy plus a 20 Gy boost to the residual disease. The results indicated that synchronous chemotherapy with cyclophosphamide, adriamycin and cisplatin combined with radiotherapy significantly improved locoregional control of DSRCT and a complete response, as measured by CT assessment 2 months subsequent to radiotherapy. In conclusion, DSRCT is a rare malignancy requiring multidisciplinary treatment, including surgery, chemotherapy and radiotherapy. The results of the present study confirm that radiotherapy has a significant role in the treatment of advanced abdominal DSRCT and may contribute to durable remission.

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.

Nausea and vomiting induced by gastrointestinal radiation therapy: current status and future directions

PURPOSE OF REVIEW

Radiation therapy-induced nausea and vomiting (RINV) are common and troublesome symptoms among patients receiving radiation therapy for gastrointestinal cancers. Their impact on function, quality of life and, ultimately, cancer control warrant a review of their incidence, underlying mechanisms, treatments and research themes.

RECENT FINDINGS

Research in RINV is underrepresented relative to that in chemotherapy-induced nausea and vomiting. The incidence of RINV among patients receiving modern day radiation therapy is questioned and supportive care practice patterns vary among radiation oncologists. Antiemetic guideline recommendations for prophylactic and rescue therapy are based solely on the anatomic region being irradiated and not other patient-related, radiation therapy-related, or organ-specific dosimetric factors that likely modulate the risk of RINV. Dosimetric predictors are likely the most attainable biomarker moving forward, but only early steps have been taken. The small bowel and stomach will be the best first candidates for study among patients with gastrointestinal cancers. Studies of the mechanisms underlying RINV are conspicuously lacking. A new generation of observational studies and therapeutic clinical trials is needed, and more attention must be given to the relative impact of nausea and vomiting on the function and quality of life among specific homogeneous patient populations.

SUMMARY

Optimal supportive care strategies for RINV following radiation therapy for gastrointestinal cancers are lacking, and will not be known until future research answers the many open questions regarding the mechanisms underlying RINV, the true incidence and impact of these symptoms among patients and the best way to predict and mitigate them.

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.

Thoracic Vertebral Body Irradiation Contributes to Acute Hematologic Toxicity During Chemoradiation Therapy for Non-Small Cell Lung Cancer

PURPOSE

To determine the relationships between radiation doses to the thoracic bone marrow and declines in blood cell counts in non-small cell lung cancer (NSCLC) patients treated with chemoradiation therapy (CRT).

METHODS AND MATERIALS

We included 52 patients with NSCLC treated with definitive concurrent carboplatin-paclitaxel and RT. Dose-volume histogram (DVH) parameters for the thoracic vertebrae (TV), sternum, scapulae, clavicles, and ribs were assessed for associations with changes in blood counts during the course of CRT. Linear and logistic regression analyses were performed to identify associations between hematologic nadirs and DVH parameters. A DVH parameter of Vx was the percentage of the total organ volume exceeding x radiation dose.

RESULTS

Grade ≥ 3 hematologic toxicity including neutropenia developed in 21% (n=11), leukopenia in 42% (n=22), anemia in 6% (n=3), and throbocytopenia in 2% (n=1) of patients. Greater RT dose to the TV was associated with higher risk of grade ≥ 3 leukopenia across multiple DVH parameters, including TV V20 (TVV) (odds ratio [OR] 1.06; P=.025), TVV30 (OR 1.07; P=.013), and mean vertebral dose (MVD) (OR 1.13; P=.026). On multiple regression analysis, TVV30 (β = -0.004; P=.018) and TVV20 (β = -0.003; P=.048) were associated with white blood cell nadir. Additional bone marrow sites (scapulae, clavicles, and ribs) did not affect hematologic toxicity. A 20% chance of grade ≥ 3 leukopenia was associated with a MVD of 13.5 Gy and a TTV30 of 28%. Cutoff values to avoid grade ≥ 3 leukopenia were MVD ≤ 23.9 Gy, TVV20 ≤ 56.0%, and TVV30 ≤ 52.1%.

CONCLUSIONS

Hematologic toxicity is associated with greater RT doses to the TV during CRT for NSCLC. Sparing of the TV using advanced radiation techniques may improve tolerance of CRT and result in improved tolerance of concurrent chemotherapy.

Myeloablative chemotherapy with autologous stem cell transplant for desmoplastic small round cell tumor

Desmoplastic small round cell tumor (DSRCT), a rare, aggressive neoplasm, has a poor prognosis. In this prospective study, we evaluated the role of myeloablative chemotherapy, followed by autologous stem cell transplant in improving survival in DSRCT. After high-dose induction chemotherapy and surgery, 19 patients with chemoresponsive DSRCT underwent autologous stem cell transplant. Myeloablative chemotherapy consisted of carboplatin (400–700 mg/m²/day for 3 days) + thiotepa (300 mg/m²/day for 3 days) ± topotecan (2 mg/m²/day for 5 days). All patients were engrafted and there was no treatment-related mortality. Seventeen patients received radiotherapy to sites of prior or residual disease at a median of 12 weeks after transplant. Five-year event-free and overall survival were 11 ± 7% and 16 ± 8%, respectively. Two patients survive disease-free 16 and 19 years after transplant (both in complete remission before transplant). 14 patients had progression and died of disease at a median of 18 months following autologous transplant. These data do not justify the use of myeloablative chemotherapy with carboplatin plus thiotepa in patients with DSRCT. Alternative therapies should be considered for this aggressive neoplasm.

Peritonectomy and hyperthermic intraperitoneal chemotherapy as treatment for desmoplastic small round cell tumour

INTRODUCTION

The St George Hospital specialises in peritonectomy and hyperthermic intraperitoneal chemotherapy (HIPEC) for treatment of intra-abdominal malignancies. Despite performing around 800 peritonectomy and HIPEC procedures, we have rarely encountered desmoplastic small round cell tumours (DSRCT). We present our experiences with DSRCT, and propose peritonectomy and HIPEC as a treatment option for DSRCT.

PRESENTATION OF CASE

This is a case series of 3 cases. The first case was a 26-year-old male who presented with appendicitis which we diagnosed as DSRCT and treated with peritonectomy and HIPEC. The second case was a 14-year-old male referred to our centre for peritonectomy and HIPEC after initial presentation with a pelvic mass and treatment with chemotherapy. The third case was a 21-year-old male referred to our centre for peritonectomy and HIPEC for recurrent DSRCT after previously being treated with neoadjuvant chemotherapy and surgery without HIPEC.

DISCUSSION

DSRCT is a rare, almost exclusively intra-abdominal malignancy, which predominantly affects young males. Survival prognosis remains poor in DSRCT despite conventional treatment with surgery, chemotherapy and radiotherapy; however, HIPEC has offered promising survival results. Our recurrences with peritonectomy and HIPEC at 6 months and 15 months are comparable with the literature of 8.85 months.

CONCLUSION

In our experience, patients with DSRCT who present with nodal involvement or recurrent disease tend to recur early despite treatment with peritonectomy and HIPEC. Longer term follow up of our patients and future studies involving HIPEC in DSRCT would be useful in assessing long-term clinical outcomes and survival.

Favorable outcomes after whole abdominopelvic radiation therapy for pediatric and young adult sarcoma

BACKGROUND

Current Children's Oncology Group (COG) guidelines recommend 24 Gy whole abdominopelvic radiation therapy (WAP-RT) for pediatric patients with sarcoma with peritoneal dissemination and/or malignant ascites. However, WAP-RT has never been described for pediatric sarcoma excluding desmoplastic small round-cell tumor (DSRCT). The objective of this study was to evaluate feasibility, outcomes, and toxicity of WAP-RT in children with sarcoma and peritoneal dissemination.

PROCEDURE

Detailed records of all 10 pediatric patients with sarcoma (excluding DSRCT) treated with WAP-RT from 2001 to 2013 were reviewed.

RESULTS

Median age was 9.9 years (range, 1.7-33.8). Seven patients had rhabdomyosarcoma, 2 embryonal undifferentiated sarcoma of the liver, and 1 Ewing sarcoma. Patients received a median dose of 24 Gy with intensity-modulated radiation therapy (IMRT) to the whole abdomen and pelvis. Two patients did not complete treatment, one due to transfusion-resistant pancytopenia and one due to moderate acute gastrointestinal toxicity. At a median follow-up of 4.0 years, both relapse-free survival and overall survival were 100%. Acute hematologic toxicities were common, with 40% of patients developing a grade 4 hematologic toxicity. Most acute gastrointestinal toxicities were grade 1 and managed appropriately with anti-diarrheals and anti-emetics. Late effects varied, and half of patients are without long-term sequelae.

CONCLUSIONS

All patients remain free of disease, both locally and distantly. Although WAP-RT was associated with acute and late toxicity, treatment was feasible with supportive care. Given the excellent rates of tumor control, we recommend that all providers give WAP-RT with IMRT to patients with pediatric sarcoma and peritoneal dissemination and/or malignant ascites.

Desmoplastic small round cell tumor of the abdomen and pelvis: clinicopathological characters of 12 cases

Purpose. To study the clinical, radiological, and pathological characteristics of abdominal desmoplastic small round cell tumor (DSRCT) and investigate the optimal therapy modalities. Patients and Methods. A retrospective cohort study was performed on 12 abdominal DSRCT patients; all pathological, radiological, and prognostic data were analyzed. There were 3 patients (25%) with metastatic disease at presentation. In all 12 cases, 6 cases underwent operation and adjuvant chemotherapy (group 1, 6/12, 50%). The other 6 cases were diagnosed by fine needle aspiration or exploratory laparotomy biopsy (group 2, 6/12, 50%); all cases received four to six courses of multiple agents chemotherapy, respectively. Results. All cases were finally diagnosed as DSRCT pathologically. Among group 1, all cases underwent en bloc resection (2/6, 33%) or tumor debulking (4/6, 67%) and, following four courses of multiple agents chemotherapy, Kaplan-Meier analysis revealed that 3-year survival was 50% in group 1 versus 16.7% in group 2 (P < 0.05). Gross tumor resection was highly significant in prolonging overall survival; patients with localized solitary lesion have a better prognosis, most likely due to increased feasibility of resection. Conclusions. DSRCT is a rare malignant tumor with poor prognosis. Surgical excision with combination chemotherapy as an adjunct is mandatory for nonmetastatic cases because these modalities used in isolation may have less impact.

State of the art in oncology: high risk neuroblastoma, alveolar rhabdomyosarcoma, desmoplastic small round cell tumor, and POST-TEXT 3 and 4 hepatoblastoma

Despite advances in the treatment of pediatric cancers during the past few decades, high-risk neuroblastoma, alveolar rhabdomyosarcoma, desmoplastic small round cell tumor, and hepatoblastomas with 3 or 4 sector involvement after chemotherapy continue to present significant challenges. This review summarizes recent research on the management of these diseases, with a special focus on the use of surgical debulking, genetic analysis, immunotherapy, and chemotherapy in improving outcomes of patients with these solid tumors.