Transitional and
squamous-cell carcinomas of the bladder that were transplanted and successfully retransplanted in further passages to NMRI nu/nu mice were used to test the efficacy of
chemotherapy.
Mitomycin and
bleomycin consistently retarded
tumor growth; results with
platinex and
methotrexate were variable. Combination
therapy was not much better than single-
drug therapy. Substances that proved effective in the mouse model produced some response in the corresponding patients in a series of patients on specific
chemotherapy. In a previous study we have shown that
tumor growth of transplanted human bladder
carcinoma accelerates, unlike transplanted
renal cell carcinoma when successfully subpassaged, resulting in a uniformly fast growing rate similar in all transplanted
tumors including those which initially started with slow growing rates. Most importantly, however, tests in a given
tumor conducted on a slow-growing early passage and on a fast-growing late passage produced different results. We concluded that this finding might explain the clinical observation that
tumor remission due to
chemotherapy in patients with metastatic bladder
carcinoma does not last very long and seldom prolongs survival. It is assumed--it is not proved--that substances that proved effective in fast growing passages are probably likely to yield greater
prolongation of life than those effective in slow-growing passages.