Tumors: Wounds That Do Not Heal

SOLID tumors are composed of two discrete but interdependent compartments: the malignant cells themselves and the stroma that they induce and in which they are dispersed.1 , 2 In tumors of epithelialcell origin — carcinomas — a basement membrane is often interposed between the tumor cells and the stroma, but in other types of tumors, malignant cells directly abut on or intermingle with stromal elements.1 , 3 An appreciation of tumor stroma is essential to an understanding of the biology of tumor growth; all solid tumors, regardless of their site of origin, require stroma if they are to grow beyond a minimal size of . . .