Foreign Body Tumorigenesis

Abstract

This review deals with factors and mechanisms involved in sarcoma development upon implantation of chemically inert foreign bodies. The topic is of importance regarding cancer in asbestosis or schistosomiasis, and also in view of increasing ise of artificial implants. After detailing morphological and biological characteristics of foreign body-induced sarcomas in man and animals, the review focuses on specific properties of implants and experimental animals which determine or influence tumor incidence and latency. Included are surface properties, size and shape of implants, and species characteristics, sex, and genetic background of animals. It follows a description of recent etiologic research which has evealed foreign body tumorigenesis as a multistage developmental process. Some of the salient features are monoclonal forigin from mesenchymal stem cells of the micro-vasculature; origination of neoplastic destination and specific tumor leterminants in cells distant from the implant during the earliest stage of the tumorigenic process; the regular finding of aried aneuploidies; the importance of fibrosis and macrophage inactivity during the preneoplastic maturation process; and lirect contact with the foreign body surface as the terminal requirement for preneoplastic cells to attain neoplastic utonomy. The findings open new theoretical perspectives and experimental avenues in cancerology.