[Biopsy and cytology in the diagnosis and treatment of surgical diseases (author's transl)].

Surgical lesions of the gastrointestinal tract are usually of an ulcerous or polypoid nature. The macroscopic pathologic changes can be given a clinical diagnosis only after the histologic findings are known. Endoscopic biopsy meets this purpose. Furthermore, endoscopic snare biopsy can be a curative therapeutic procedure. Cytology should only be used as a method of second choice, for example when stenosis proximal to the lesion hinders biopsy.