The reported case involved a 73-year-old diabetic man who died of the condition after presenting with fulminant gangrene of the right thigh. Clostridium septicum was cultured from the quadriceps muscle postmortem. At autopsy, in addition to gangrene, Duke's A adenocarcinoma of the cecum was observed, which had not been diagnosed while he was still alive. The patient had two risk factors for the development of spontaneous myonecrosis due to Clostridium septicum, namely an occult carcinoma of the cecum and diabetes mellitus. The authors note that clostridial gas gangrene most frequently occurs in a contaminated wound following traumatic injury or a surgical procedure. Immunosuppression may also be a contributing factor as spontaneous clostridial myonecrosis has been found in patients with neutropenia, renal transplantation, and chemotherapy. Death investigations involving this disease should include a medical history, with special attention paid to such conditions as immunosuppression, carcinoma, non-neoplastic diseases of the gastrointestinal tract, diabetes mellitus, and bone marrow diseases. The autopsy should be complete and include an examination of the gastrointestinal mucosa. 6 references and 3 figures