[Sarcomatoid spindle-cell epithelioma. Anatomicoclinical study of 15 cases].

Sarcomatoid spindle cell carcinoma, which is a rather rare cancer, is of epithelial origin, but histologically resembles a connective spindle cell sarcoma. It remains subject to controversy, especially concerning the reality of epitheliomesenchymatous transformation of the neoplastic cells which, indeed, take on not only the shape but also the behaviour of connective cells. The debate is of both a dogmatic and practical nature, dogmatic in that it has bearing on the question of cellular specificity, and practical in that histological transmutation has repercussions on the macroscopic aspect of the tumor, its clinical evolution and even its behaviour vis-a-vis radiation therapy. The preferred, but not the only, sites of such tumors are the upper respiratory and digestive tracts. In many cases, they occur in subjects who many years previously had undergone radiological treatment, with the tumor appearing in the irradiated area. The problems raised by these unusual cancers explain and seem to justify the publication over the last few years of isolated cases or series of reports made in various centers. The present work concerns 15 anatomoclinical cases observed at the Institut Curie.