Malignant transformation of "benign" cystic mesothelioma of the peritoneum.

Abstract

Peritoneal mesothelioma is being diagnosed with greater accuracy as a result of immunocytochemical analysis. The histological type of peritoneal mesothelioma has a great influence on the natural history of the disease. Benign cystic mesothelioma is a definite clinical entity; however, the absence of a uniform approach to treatment and a lack of long-term follow-up of patients seriously hinders an accurate assessment of the disease process. The medical history of a patient with a diagnosis of benign peritoneal cystic mesothelioma followed for 10 years is presented. The medical literature of this disease is reviewed. The patient was a 36-year-old woman initially diagnosed with benign cystic peritoneal mesothelioma; however, after six surgical procedures with the aim of reducing the volume of intraperitoneal fluid and cysts, the disease developed into an aggressive, diffuse malignant mesothelioma. Involvement of abdominal incisions, invasion of lymph nodes, and invasion of the viscera occurred. Peritoneal cystic mesothelioma is a disease in need of careful longitudinal studies in order to better define the clinical course of these patients. This case report along with a literature review suggests caution in the assessment of cystic mesothelioma as a benign process. This patient had a clear malignant transformation of benign cystic mesothelioma to an invasive and potentially lethal process.