[Cryosurgery of anorectal cancer and the freezing-induced changes].

Inoperable ano-rectal cancers were treated with cryo-surgery supplemented in suitable cases with brachy-radiotherapy. An account is given of the authors' clinical experience and of the morphological changes caused by cryotherapy at -130 degrees to -140 degrees C. In some cases treatment resulted in epithelisation of the tumourous ulcer and in a more than two-year survival of patients in the 70 to 80 age group. The macroscopic picture was characterized by stasis oedema, followed by the necrosis of the tumour, while the light and electron microscopic pictures showed lesions of the cell membrane system -- particularly of the mitochondria, the endoplasmic reticulum and of the Golgi's apparatus -- which was more marked in the tumour cells than in the cells of the surrounding intact mucous membrane. The destruction of the tumour cells is brought into relation with this finding. Laminarly growing, not deeply infiltrated tumours whose cranial edge can be reached with the finger seem to be suited to cryo-surgery.