A 70‐year‐old male with hypothyroidism, BPH, and alcohol dependence in the past presented to the hospital with a 3‐month history of weight loss (35 pounds), anorexia, and abdominal distention for 2 weeks. He had no abdominal pain, nausea/vomiting, or dysphagia. His physical examination was within normal limits except for mild ascites and muscle wasting. His laboratory data revealed mild anemia and mild hypoalbuminemia (albumin 2.9 g/dL). His liver function tests, coagulation studies and basic metabolic panel were normal. He underwent a diagnostic and therapeutic paracentesis with removal of 3 L of clear/yellow fluid. The fluid albumin was 2.2 g/dL with a serum‐to‐ascites albumin gradient (SAAG) of 0.7 g/dL, total protein of 4.2 g/dL, and cytology and culture were negative. AFB, CA19‐9, and CEA were all within normal limits. CT‐TAP demonstrated ascites with mesentery and omentum thickening consistent with peritoneal carcinomatosis, a necrotic liver mass, a 3‐cm soft tissue abdominal mass and lymphadenopathy. The chest CT showed extensive bilateral pleural‐based plaques with no pulmonary mass, pleural effusion, or lymphadenopathy. The patient underwent an endoscopic ultrasound with biopsy of a peritoneal inplant. The biopsy demonstrated a malignant neoplasm with some features of mesothelioma, but was inconclusive. There were no gastrointestinal masses present on EGD. A laparoscopic direct surgical biopsy of a large peritoneal tumor demonstrated malignant mesothelioma. The patient had occupational exposure to asbestos working as an insulator.
The most common cause of ascites is cirrhosis. Other causes of ascites include cancer, heart failure, tuberculosis, pancreatic disease, and dialysis. Malignancy‐related ascites occurs with ovarian, bladder, colon, gastric, breast, pancreatic, lung, and liver carcinomas, and lymphoma. A very rare cause of ascites is malignant peritoneal mesothelioma (MPM), which occurs in about 400 cases annually in Ihe United States. MPM affects the serosal membranes of the peritoneum and is associated with asbestos exposure. In this patient, cirrhosis was initially considered but CT evidence suggested malignancy‐related peritoneal carcinomatosis. In determining the primary cancer, tumor markers were negative, and no dominant masses were seen in the lung, pancreas or Gl system. Cytology of the ascitic fluid was negative, EUS guided biopsies were inconclusive. The final definitive diagnosis of MPM was obtained by a laparoscopic surgical biopsy of the peritoneal implant.
MPM is a rare cause of ascites and can be difficult to diagnose. This diagnosis must be considered in patients with new‐onset peritoneal carcinomatosis and ascites. The social history of work‐related exposure to asbestos is very important in the evaluation process.
M. Cratty, none.