Unraveling Peritoneal Mesothelioma: A Case-Based Discussion on Diagnosis and Management.

Peritoneal mesothelioma is a rare and aggressive tumor, and its management remains poorly standardized in the literature. This case highlights the diagnostic and therapeutic challenges through a 56-year-old woman with no significant medical history or known asbestos exposure, who presented with progressive abdominal distension and postprandial vomiting. Imaging revealed diffuse nodular peritoneal thickening and large-volume ascites. A laparoscopic biopsy confirmed malignant epithelioid mesothelioma, supported by immunohistochemical positivity for cytokeratin 7 (CK7), calretinin, and Wilms tumor 1 (WT1). Treatment was based on systemic chemotherapy with platinum (cisplatin/carboplatin) and pemetrexed, which elicited a rapid initial response. However, the long-term efficacy remains uncertain due to the aggressive nature of the disease. The absence of standardized treatment underscores the necessity for multidisciplinary management.