Preserving Bladder Function, Increasingly an Option in the Treatment of Cancer
A radical cystectomy (complete removal of the bladder) is currently the standard treatment for patients with bladder cancer that has invaded the muscular layer of the bladder. However, long-term follow-up results from a clinical trial recently published in theJournal of Oncology indicate that through careful monitoring, select patients with muscle-invasive bladder cancer that undergo bladder-sparing treatment may achieve comparable long-term survival to those undergoing a radical cystectomy.
The bladder is a muscular organ located in the lower abdomen that serves to store urine. Ninety percent of bladder cancers originate in the inner lining of the bladder, which is composed of specific cells called transitional cells. This type of cancer is called transitional cell carcinoma (TCC).
A transurethral resection (TUR) is a procedure which may be utilized for diagnostic and treatment purposes for bladder cancer. A thin, lighted tube is placed inside the urethra (tube leading from the bladder to outside the body) so that the physician can examine the lining of the bladder. The physician is also able to remove samples of tissue or remove some or all of the cancer in the bladder through this tube. In addition, chemotherapy or anti-cancer agents can be directly delivered into the bladder at the time of TUR.
Previous clinical trials have demonstrated that the removal of cancer through a TUR in select patients with muscle-invasive bladder cancer can produce 5-year survival rates comparable to that of a radical cystectomy
1,2. However, physicians are hesitant to use TUR as definitive treatment for muscle-invasive bladder cancer for a few reasons: 1) optimal treatment and surveillance schedules have not yet been established, 2) specific patient characteristics defining who would benefit most from this procedure have not been determined, and 3) lack of definitive information exists regarding this issue.
Recently, long-term results have been reported from a clinical study evaluating the use of TUR as treatment for muscle-invasive bladder cancer. Patients in this study underwent an initial diagnostic TUR, at which time their cancer was removed. All patients had cancer that invaded only the inner muscular layer of the bladder. Patients were then advised to undergo a second TUR to determine if their cancer had returned. Physicians removed a sample of tissue from the location of the initial cancer, as well as from healthy looking tissue layers surrounding the area to test for the recurrence of cancer. If patients had a muscle-invasive recurrence, they were advised to undergo an immediate radical cystectomy. If patients had no recurrence or a recurrence of cancer in superficial layers only (invading only the innermost layers lining the cancer prior to the muscle), they had a choice of an immediate radical cystectomy or follow-up bladder examinations every 3 to 6 months (and repeat TURs as necessary) for at least 10 years.
Ten years following initial treatment, patients who had no cancer recurrence as determined by the follow-up TUR achieved an 82% survival rate when treated with bladder-sparing surgery, compared with a 65% survival rate in patients treated with cystectomy. In addition, nearly 70% of this group of patients treated with bladder-sparing therapy were able to keep their bladder for over ten years. Conversely, in patients who had a superficial cancer recurrence, those treated with bladder-sparing surgery achieved a 10 year survival of 57%, compared with 76% for those treated with cystectomy. Only 27% of these patients treated with bladder-sparing surgery were able to keep their bladder for over 10 years.
These results are exciting in that they indicate that bladder-sparing procedures may be just as effective in achieving long-term survival for patients as a radical cystectomy. However, it is crucial to understand that if muscle-invasive cancer returns following initial treatment, more radical measures such as cystectomy appear to be necessary in order to provide superior long-term outcomes.
Patients with muscle-invasive bladder cancer may wish to speak with their physician about the risks and benefits of bladder-sparing treatment or of participating in a clinical trial further evaluating bladder-sparing options. Sources of information regarding ongoing clinical trials include listing services provided by the National Cancer Institute (cancer.gov)
- Herr HW,Journal of Urology, Vol 138, pp1162-1163, 1987
- Solsona, et al.Journal of Urology, Vol 147, pp 1513-1517, 1992