Introduction: Peritoneal angiosarcoma is an extremely rare sarcoma (0.01287% incidence per 100,000) with an aggressive course and a poor prognosis. In this case, the manifestation of peritoneal angiosarcoma was ascites, which caused difficulty in early diagnosis and the diagnosis of peritoneal angiosarcoma, was made only after the surgery.
Patient concerns: A 61-year-old man working in Mainland China presented with a 1-month history of abdominal distension. A contrast-enhanced abdominal computed tomography (CT) scan revealed peritoneal carcinomatosis with massive ascites. However, his tuberculosis (TB) polymerase chain reaction was negative. The ascites cell block and cytology also revealed negative for malignant cells. The patient underwent intra-abdominal tumor excision. After the operation, the patient's blood pressure (BP) dropped. Due to the state of shock, he was transferred to an intensive care unit (ICU).
Diagnoses: According to the pathology report, the neoplastic cells were positive for cytokeratin, cluster of differentiation 31 (CD31), cluster of differentiation 34 (CD34), and negative for cytokeratin 7 (CK7), cytokeratin 7 (CK20). Therefore, the diagnosis of epithelioid angiosarcoma was made.
Interventions: The patient took 400 mg of Pazopanib once a day.
Outcomes: Even though vasopresser was used, the patient's BP was still low. Finally, he expired.
Lessons: Initialy, the patient presented with abdominal distension and large amount of ascites in the beginning. TB peritonitis was highly suspected after the abdominal CT scan. Therefore, surgical procedures would be essential in the identification of proper diagnosis. In the future, the diagnosis of peritoneal epithelioid angiosarcoma should also be taken into consideration for patients with abnormal ascites besides the common diagnoses of TB, liver cirrhosis, and infection.