Introduction: Malignant Rhabdoid Tumors (MRT) are exceedingly rare neoplasms that characteristically occur in infants and children and sparsely develop in adults. Primary MRTs of the omentum are particularly rare.Presentation of Case: A previously healthy 24-year-old male who presented with progressive abdominal distention and nausea. Further investigations revealed ascites with multifocal omental-based tumors. Biopsy with immunohistochemistry demonstrated dually positive cells for cytokeratin and vimentin and loss of Integrase Interactor 1 (INI1), and Next generation sequencing showed a copy number loss of SMARCB1 which established the diagnosis of malignant rhabdoid tumor. The patient’s clinical course was characterized by rapid local and metastatic progression with subsequent clinical deterioration, and he expired within three weeks of his initial presentation.Conclusion: Herein we describe the clinical course, difficulty with diagnosis, and paucity of treatment options for a rare and very aggressive malignant tumor. The ideal treatment regimen for MRTs has yet to be elucidated and additional studies are required to discern therapies that offer benefit
