Peritoneal silicosis

A 73-year-old man with a clinical diagnosis of pulmonary silicosis (long-standing exposure to silica, pulmonary infiltrates, and flu-like symptoms) presented to the emergency room with fever, acute biliary colic, and cholelithiasis. The patient had a 2-year status postchemotherapy with complete remission of hepatic and splenic malignant lymphoma. At laparotomy we found studding of the undersurface of the diaphragm with multiple small dark nodules. Owing to the patient's history of previously treated abdominal malignant lymphoma, the lesions were grossly interpreted as abdominal lymphomatosis. The microscopic appearance of the lesions suggested silicotic nodules, which were confirmed by digital scanning electron microscopy and roentgenographic microanalysis performed on formalin-fixed, paraffin-embedded tissue. This is an unusual extrapulmonary pattern of peritoneal seeding in silicosis.