"Our findings may help improve the guidelines doctors use for follow-up care for superficial bladder cancer," says lead author Yan Yan, MD, Ph.D., assistant professor of surgery. "They also could lead to a better understanding of why these tumors recur."
Doctors will diagnose some 56,500 new cases of bladder cancer this year, according to the American Cancer Society. It is the fourth most common cancer in men and the ninth most common in women. About 80 percent of those cases are superficial bladder cancer, cancer that has not yet invaded the deeper layers of the bladder wall. The disease recurs in more than half of those patients and is fatal 20 percent of the time.
"Little is known about the biology of multiple sequential recurrent tumors or about which patients are most at risk for sequential recurrence," says Yan, who also is a member of the cancer prevention and control program at the Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine.
The study involved 270 patients with superficial bladder cancer who were treated between January 1994 and April 1999; follow-up time ranged from one to 54 months. Of these patients, 47 percent had one or more recurrences, 14 percent had two or more recurrences, and 5 percent had three or more recurrences. The researchers found that the average time from initial treatment to first recurrence was 23 months, while the time to second and third recurrence averaged 15 and 13 months respectively.