Desmoplastic small round cell tumors (DSRCTs) are rare aggressive neoplasms that frequently present with large symptomatic intraabdominal masses. We examined the effects of multimodal therapy including induction chemotherapy, aggressive surgical debulking, and external beam radiotherapy on patients with DSRCT. Institutional Review Board permission was obtained. Sixty-six patients were diagnosed by histology, immunohistochemistry, and or cytogenetics as having DSRCT at our institution from July 1, 1972, to July 1, 2003. Data were collected on patient demographics, presenting symptoms, tumor location and extent, treatment regimen, and overall survival. A majority of patients were male (91%), Caucasian (85%), andwith amedian age of 19 (7-58) years old at diagnosis. The most common presenting complaint was an intraabdominal mass (64%). In 63 patients (96%), the primary tumor was located in the abdomen or pelvis. Thirty-three (50%) had positive lymph nodes and 27 (41%) had distant parenchymal metastases at diagnosis. Overall, 3-and 5-year survivals were 44%and 15%, respectively. Twenty-nine of these patients (44%) underwent induction chemotherapy (P6), surgical debulking, and radiotherapy. Three-year survival was 55%in those receiving chemotherapy, surgery, and radiotherapy vs 27%when all 3 modalities were not used (P < .02). Gross tumor resection was highly significant in prolonging overall survival; 3-year survival was 58%in patients treated with gross tumor resection compared to no survivors past 3 years in the nonresection cohort (P < .00 001). Ten patients (15%) have no evidence of disease with a median follow-up of 2.4 years (range, 0.4-11.2 years). Multimodal therapy results in improved survival in patients with DSRCT. Aggressive surgical resection of these extensive intraabdominal neoplasms correlates with improved patient outcome. Desmoplastic small round cell tumors (DSRCTs) are rare of neoplasms that frequently present with large symptomatic intraabdominal masses. We examined the effects of multimodal therapy including induction chemotherapy, aggressive surgical debulking, and external beam radiotherapy on patients with DSRCT. Institutional Review Board permission was Sixty-six patients were diagnosed by histology, immunohistochemistry, and or cytogenetics as having DSRCT at our institution from July 1, 1972, to July 1, 2003. Data were collected on patient demographics, presenting symptoms, tumor location and extent, treatment The majority common patients were male (91%), Caucasian (85%), and with a median age of 19 (7-58) years old at diagnosis. The most common presenting complaint was an intraabdominal mass (64% The primary tumor was located in the abdomen or pelvis. Thirty-three (50%) had positive lymph nodes and 27 (41%) had distant parenchym Three-year survivals were 44% and 15% respectively. Twenty-nine of these patients (44%) underwent induction chemotherapy (P6), surgical debulking, and radiotherapy. Three-year survival was 55% in those receiving chemotherapy, surgery, and radiotherapy vs 27% when all 3 modalities were not used (P <.02). Gross tumor resection was highly significant in prolonging overall survival; 3-year survival was 58% in patients treated with gross tumor resection compared to no survivors past 3 years in the nonresection cohort (P <.00 001). Ten patients (15%) with no evidence of disease with a median follow-up of 2.4 years (range, 0.4-11.2 years Multimodal therapy results in improved survival in patients with DSRCT. Aggressive surgical resection of these extensive intraabdominal neoplasms correlates with improved patient outcome.