Pseudomyxoma Peritonei Presenting With Progressive Abdominal Distension and Abdominal Hernia: A Case Report.

Pseudomyxoma peritonei (PMP) is a rare clinical condition characterized by progressive mucinous ascites, most commonly arising from a low-grade appendiceal mucinous neoplasm (LAMN). We report the case of a 53-year-old man with a past medical history of type 2 diabetes mellitus who presented with progressive abdominal distension, constipation, weight loss, and a supraumbilical hernia. Imaging modalities, including ultrasonography, magnetic resonance imaging (MRI), and computed tomography (CT), revealed omental caking, ascites, and hepatic scalloping. Diagnostic laparoscopy revealed mucinous nodules and an abnormal appendiceal tip, and histopathology confirmed LAMN with PMP. The patient had an uneventful recovery following laparoscopic appendectomy and peritoneal biopsies and was referred to a specialized oncology center for consideration of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC). This case highlights the diagnostic challenges of PMP and underscores the importance of early detection and multidisciplinary management to achieve optimal outcomes.