[Histopathologic observation of anti-tumor effects of bleomycin and irradiation on cancers of the tongue].

Nine cases of squamous cell carcinoma of the tongue were treated by either intramuscular or local injections of total 60 to 200 mg of Bleomycin (BLM), and 7 cases by total doses of 1,200 to 5,320 rads of irradiation, followed by surgical removal of primary neoplasm. The histologic examination of the biopsied and surgical specimens from each case was done focussing on the antitumor effect of both treatments. In the cases with keratinizing component more than 25% in the biopsy specimens, the earliest change due to BLM was vacuolar degeneration of proliferating cells either at the base of superficial cancer epithelia or at the periphery of invading cancer foci. When the proliferating cancer cells disappeared, an appearance of invading cancer foci resembled to that of ectopic islands of normal squamous epithelium. These foci of differentiated squamous cell carcinoma gradually underwent morphological change into the so-called cancer pearls. Finally, the cancer pearls degenerated, leaving foreign bodies consisting of concreted keratin. The stromal reaction was characterized by the formation of granulation tissues accompanying significant numbers of foreign body giant cells. In the cases of lingual carcinoma with poor squamous differentiation, these processes were indistinct. Instead, the proliferating anaplastic cancer cells were markedly reduced and the remaining cancer cells transformed into large bizarre cells, probably at degenerative stage. On the histologic level, irradiation showed essentially similar antitumor effect to BLM, except for the rapid formation of concreted keratin bodies accompanying more abundant foreign body giant cells and the presence of irregular granulation tissues at different stages. We concluded that both BLM and irradiation had a powerful antitumor action on squamous cell carcinoma of the tongue. It is necessary, however, to establish an appropriate treatment modality through the more detailed histologic evaluation of a number of lingual cancer patients in consideration of the natural history of this neoplasm.