For decades, the fear of becoming impotent and incontinent as a result of surgery for prostate cancer kept many men from undergoing screening and treatment, leading to many deaths that might have been prevented. This situation has changed drastically in recent years, with the use of new surgical approaches to removing the prostate that spare nerves and tissues in the area and can avoid the dreaded side effects. In addition, many men once thought to be "incurable" are now able to avoid surgery altogether and live longer lives with more effective radiation therapy.
The two physicians who pioneered those treatments and were instrumental in changing prostate cancer treatment--Dr. Patrick C. Walsh, director of the Department of Urology at Johns Hopkins University, and Dr. Malcolm A. Bagshaw, Professor Emeritus of Cancer Biology at Stanford University--shared the 1996 Charles F. Kettering Prize for outstanding contributions to the treatment of cancer, awarded by the General Motors Cancer Research Foundation.
A Unique Route to Less Fearsome Surgery
In an era of "high-tech" medicine and imaging, it was the old-fashioned learning tools of anatomic studies and cadaver dissection that led to an new anatomic approach to radical retropubic prostatectomy, which not only spares the nerves that supply the penis but also can greatly reduce incontinence and severe intraoperative bleeding.
In the 1970s, Dr. Patrick Walsh embarked on a series of anatomic studies to delineate the structures surrounding the prostate, in an effort to prevent these problems. Initially, he mapped the anatomy of the dorsal vein complex around the prostate, and was able to eliminate the severe bleeding that typically hampered surgery. After noting that one of his patients was fully potent after the improved surgery, Dr. Walsh set out to find out why most men became impotent. By dissecting infant cadavers, in which pelvic nerves and tissues are more clearly seen, he was able to locate the nerves that supply the corpora cavernosa and give rise to erections. "These nerves had never been charted. It was assumed that these nerves ran through the prostate, but it turned out that they ran outside the prostate," said Dr. Walsh. By not cutting or only removing nerves on one side, he was able to preserve potency.
In 1990, Dr. Walsh charted the anatomy of the striated sphincter (which controls urine retention) and refined the surgery further to avoid damage to the bladder neck and urethra, preventing incontinence. "It is now possible to remove the prostate with excellent tumor control and improve the quality of life in carefully selected patients," he commented.
Dr. Walsh has made other important contributions to the field, including the characterization of familial and genetic factors responsible for prostate cancer. He has established the largest registry of men with hereditary prostate cancer and has improved the use of prostate-specific antigen (PSA) testing in the early diagnosis and staging of the cancer.
Demonstrating the Efficacy of Radiation Therapy
Radiation therapy is now the treatment of choice for many men with both early-stage and even more advanced prostate cancers. But that wasn't always the case. Before Dr. Malcolm Bagshaw's pioneering work, prostate cancer was considered by many to be a radioresistant tumor.
Dr. Bagshaw and collaborators at Stanford University showed that high-dose, small-field radiation could allow selected patients to undergo potentially curative therapy without the need for surgery. Moreover, radiation therapy was associated with an extremely low incidence of urinary incontinence and the preservation of sexual potency in over 50% of patients treated. This is especially important since the incidence of prostate cancer rises with age, and many elderly men have coexisting medical problems that may make surgery risky.
"We have done the largest single series, 1,400 patients treated with external beam radiation for prostate cancer, some were in their 40s but others were in their 80s when treated," says Dr. Bagshaw. "In the early stages of the disease, we showed that radiation provides a high likelihood of tumor control and the same life expectancy as a man who doesn't have prostate cancer. This is true regardless of the age of the patient."
His work also resulted in replacement of cobalt-60 megavoltage therapy with the linear accelerator for the treatment of locally advanced cancer. Other innovations by Dr. Bagshaw include the development of techniques to identify and shield the rectum, anal canal and sphincter, small bowel, and pubic bone, as well as uninvolved portions of the urethra, from radiation. "Radiotherapy techniques for localized prostate cancer devised by Dr. Bagshaw have become an important standard of care throughout the country," remarked Joseph G. Fortner, md, President of the General Motors Cancer Research Foundation.
In the era before PSA testing was able to detect prostate cancer in its earliest stages, Dr. Bagshaw carried out a number of important studies to refine radiation treatment. One series of studies "mapped" the spread of prostate cancer to the lymph nodes, showing a progressive spread from the nodes nearest to the gland to the para-aortic nodes, and led to modification of the radiation field to include all of the potentially affected nodes. Other studies defined the role of preoperative testing and exploratory laparotomy for patients with apparent localized disease. His work has also helped define the natural history of prostate cancer.
Lifetimes of Achievement
Drs. Bagshaw and Walsh have each published over 100 papers and numerous book chapters on prostate cancer, as well as edited several textbooks.
Dr. Walsh is the author of The Prostate: A Guide for Men and the Women who Love Them (Johns Hopkins Press, 1995), aimed at the lay public. He earned both his undergraduate (1960) and medical degrees (1964) from Case Western Reserve University in Cleveland, Ohio. Dr. Walsh joined the Johns Hopkins faculty in 1974 as Chairman of Urology. His first paper on impotence following radical prostatectomy was published in 1982.
Dr. Bagshaw's first major study on the role of radiotherapy in prostate cancer was published in 1965. He received his undergraduate degree from Wesleyan University in Middletown, Connecticut and his md from Yale University School of Medicine in 1950. Dr. Bagshaw joined the Stanford University faculty in 1956, where he became the first Henry S. Kaplan and Harry Lebeson Professor in Cancer Biology in 1992.