Purpose: A 73-year-old female patient with a history of hypertension, gastro-esophageal reflux disease, and hemorrhoids presented with abdominal distention, pain, and alternating constipation and diarrhea. On exam, she was hypotensive, and her abdomen was distended with a positive fluid wave. Computer tomography (CT) imaging of the abdomen showed minimal to moderate bilateral pleural effusions, and moderate abdominal pelvic ascites. Diagnostic paracentesis demonstrated a serum ascites-albumin gradient (SAAG) of greater than 1.1, with cytology revealing cells of malignant adenocarinoma, mullerian in origin. While the majority of patients who present with ascites have underlying liver disease, 20% demonstrate an extrahepatic etiology, half of which are malignancy-related ascites.1 Malignant ascites is a sign of peritoneal carcinomatosis,2 diagnosed when paracentesis demonstrates positive cytology, elevated protein concentrations, and a low SAAG.3 Accurate characterization of the malignancy is vital, as proper treatment can result in positive responses in a majority of patients, with a minority making complete recovery.4 Though surgical debulking with adjuvant chemotherapy is the preferred treatment,5 chemotherapy alone was initiated, as our patient was a poor surgical candidate. She responded to carboplatin and paclitaxel, with CA-125 decreasing from 15,000 to 600 over 5 months, but chemotherapy was stopped due to an illness, and her CA-125 increased to 7,000 over two months. A follow-up CT showed an increase in peritoneal carcinomatosis with upper abdominal lymphadenopathy and omental disease. She has since restarted chemotherapy. Common presentations of rare diseases are difficult to diagnose. This patient's rare cause of ascites, mullerian adenocarcinoma, is a prime example of this scenario. As ascites can signify a multitude of different diseases and pathologies, maintaining a broad differential when faced with ascites is important to decrease unnecessary treatment, reduce hospitalizations, and improve patient care.