Abstract: | The results of the study of three implanted ureteric tumors from a primary transitional cell carcinoma of the renal pelvis are reported. Using both light microscopic immunohistochemistry and transmission electron microscopy, the stroma of the tumor showed consistent evidence for the production of at least its collagenous component by the neoplastic cells. Our findings argue with the notion that occasional fibroblasts and other cells of mesenchymal origin could play a major role in this phenomenon. Therefore, it seems plausible to suggest that what is happening in these tumors is similar to the behavior of malignant cells in scirrhous 'infiltrating' carcinoma of the breast and other sites. |