Histological differences between the cell types of the irradiated lung cancers

In order to estimate the histological finding caused by irradiation in the lung cancer, we examined at first 4NQO-induced transplantable lung cancer received x-ray irradiation in the experimental animals. The following result was obtained. Transplanted cancer cells showed 2 types of degenerative or necrotic change caused by irradiation. The first type was ''atrophic'' change, and the other was ''vacuolar''. Human-lung cancers irradiated preoperatively were histologically examined based on the above-mentioned experimental result. So, the cancer cells of epidermoid carcinomas exhibited mainly ''vacuolar'' change, and that of adenocarcinomas showed ''atrophic'' change. There was no obvious difference in the histological appearance between epidermoid and adenocarcinomas in the manner of absorption of necrosed cancer cells. But there were plenty of the necrosed or/and these absorpted foci in epidermoid carcinomas than in adenocarcinomas. (auth.)