A CASE OF MALIGNANT MESOTHELIOMA ORIGINATING FROM THE OMENTUM

Solid tumors originating from the omentum are rare. Most of these tumors are difficult to diagnose before operation. Recently a case of primary omental tumor which was diagnosed before operation was encountered. The patient was a 67-year-old woman. During a periodic health check, a mass was detected in the subhepatic space. Because abdominal computed tomography and ultrasonography did not allow a definite diagnosis, an angiography was performed. This patient was angiographically diagnosed as having an omental tumor and was operated on. The extirpated tumor weighed 120g, and its surface was smooth and showed a partial necrosis. A pathological examination using various stains allowed a diagnosis of malignant mesothelioma. The postoperative course was excellent, and she has been followed on an ambulant basis. Angiography is particularly useful for diagnosis of omental tumors. It should be carried out before surgery. Until now, 6 cases of malignant mesothelioma have been reported in Japan, and the tumors were surgically removed in 3 cases. To prolong the survival period for such patients, the best way would be the total surgical removal of the tumor whenever possible.