URINARY BLADDER CANCER

Coordinators:

Dr. George T. Bryan Dr. Osamu Yoshida

The excellent progress of the Bladder Cancer program area is not accidental but has transpired and developed during the past several years through the exchange of information and of scientists. Carcinogenesis and bladder cancer is not only important in the U.S. but equally important to other industrial nations due to greater exposure to environmental and chemical carcinogens. The Japanese scientists have long been interested in chemical carcinogenesis and have been investigating pure substances for cause. Studies on new techniques and insights in research have naturally led to cooperative studies.
The program has initiated collaborative studies on chemical carcinogenesis and related areas and has brought to focus the increasing incidence of bladder cancer in different countries. The incidence in Japan has shown a strikingly sharp upward slope. Although the present efforts are modest, the importance of bladder cancer research will gain more prominence and should receive considerable emphasis and thrust for continued research activities.
The establishment of the NCI National Bladder Cancer Program (NBCP) and the participation of the Japanese scientists in the NBCP meetings have contributed considerably to this program area. The Japanese scientists will be invited to participate in the annual meeting and workshops sponsored by the NBCP.
As the result of the planning meeting in Wisconsin, February 1975, the agreement was reached to hold the joint conference on “Experimental Models for Bladder Cancer” in Hawaii, December 1975, to discuss and demonstrate the current status of methods utilized to induce urinary bladder cancer in experimental animals, to share knowledge of pathogenesis and histopathology; and to depict and describe similarities and differences exhibited by these models and human urinary bladder cancer. In this seminar, fruitful discussions went on about chemical carcinogens animal species, histogenesis and mechanism of bladder carcinogenesis. Those urinary bladder cancer specimens of experimental animals induced by N-butyl-N-(4-hydroxy-butyl) nitrosamine (BBN) were presented by the Japanese scientists to compare with those induced N-[4-(5-nitro-2-furyl)-2-thiazolyl] formamide (FANFT), the latter carcinogen being extensively used by American scientists. The Japanese scientists introduced a proximate form of BBN and a U.S. scientist presented a study on urinary bladder carcinogenesis by 2-acetylaminofluorene. The seminar also included a slide conference of urinary bladder cancer specimens of several experimental animals. Participants discussed the relevance of experimental bladder carcinogenesis studies to humans freely and rationally. At the end of the seminar, discussions of promising new leads for further exploration, evaluation of the meeting, suggestions for further meetings were made.
The program is developed in 3 disciplinary areas: urology, surgery and pathology. There are 4 or 5 meetings being planned for the next 3 to 4 years. A workshop on the “Biochemical Aspects of Bladder Cancer” is being planned for 1976 in Japan. Tentative plans for meetings on pathology and treatment of human bladder cancer etiology, epidemiology of bladder cancer, and bladder tumor host response are being made for 1976-1978.
Three Japanese scientists were sent to the U.S.A. for collaborative researches. Other investigators from both countries visited each other outside the auspices of the U.S.-Japan Cooperative Cancer Research Program, but related to its purposes. Long-term visits are being planned for junior scientists and short-term visits for senior investigators.