[The cancer cell and the connective tissue. A historical retrospect].

Since the introduction of microscopic examination of tumours, many researchers have dealt with the relationship between cancer cells and connective tissue. Rudolf Virchow's opinion that carcinomas derive from connective tissue was soon disproved by the studies of Cornil, Thiersch, and Waldeyer, but no clue was provided to the reason for the invasion of the epithelium. Julius Cohnheim and particularly Hugo Ribbert were of the opinion that invasion of the epithelium was only possible in the case of a primarily altered connective tissue. Ultimately the stroma determines malignant growth. From 1902, Max Borst finally formulated the views on tumour-stroma-relationship that are still valid today and postulated interrelations which can only be proved and confirmed by modern molecular biological methods.