Rationale:Neoplasms with perivascular epithelioid cell differentiation (PEComas) are mesenchymal tumors that rarely occur in the colon. Here, we report the occurrence of a malignant PEcoma in the colon using18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT).Patient concerns:A 55-year-old woman was admitted to the hospital with abdominal pain for 10 days and a self-induced abdominal mass for 3 days.18F-FDG PET/CT imaging showed a large hypermetabolic nodule and mass in the right mid-upper abdomen with heterogeneous density and a further increase in metabolism on the delayed scan.Diagnoses:PEComa of the colon.Interventions:Tumor resection was performed.Outcomes:The patient is well after 2 months of treatment, pending further follow-up.Lessons:Malignant perivascular epithelioid cell tumors originating in the colon are extremely rare, and our report suggests that PEComa should be considered as a differential diagnosis for18F-FDG gastrointestinal malignancies. Additionally,18F-FDG PET/CT may play a key role in the staging and extent of lesions in intestinal malignancies.