Amylase producing lung cancer. Electronmicroscopical and biochemical studies.

A case of the lung cancer associated with marked elevation of serum (7820 IU/1) and of urinary amylase (2225 IU/1) was autopsied. Material was examined histopathologically, electronmicroscopically and biochemically. The pulmonary tumor tissues showed histological pattern of papillary adenocarcinoma. In addition to the small round bodies which were very similar to secretory granules, many large round bodies were noticed, diffusely distributed in the tumor cell. These large round bodies ranged from 0.2 to 0.7 micrometers in diameter and showed a lamellar or annular pattern. The soluble phase of the homogenized pulmonary tumor tissues had an amylase level of 11,300 IU/g of protein, which consisted of S-type isoamylase with minor components. Cholesterol, triglyceride and phospholipid were also present at greater concentration in the tumor tissue than the normal pulmonary tissue. The large round bodies appeared too, to be amylase including bodies from the electronmicroscopical and biochemical findings.