Intravesical treatment: Hazard to bladder cancer survival?

September 1, 2006

Atlanta-A study presented at the AUA annual meeting by researchers from Columbia University in New York asked the provocative question, Are physicians overusing intravesical therapy in patients with T1 bladder cancer?

Atlanta-A study presented at the AUA annual meeting by researchers from Columbia University in New York asked the provocative question, Are physicians overusing intravesical therapy in patients with T1 bladder cancer?

The question is worth looking into. That seemed to be the consensus answer derived from lengthy exchanges that followed the presentation.

"I saw a number of patients during the past year who were failing several cycles of intravesical therapy before eventually going on to cystectomy," said first author Erica Lambert, MD, a fourth-year urology resident at Columbia, working with James McKiernan, MD, and colleagues. "I started to wonder if we might be spending too much time giving patients with high-risk disease repeated courses of intravesical therapy."

The most significant of these was that patients who were diagnosed before 1998 had 69.7% disease-free survival at 7 years. Those diagnosed after 1998 had a disease-free survival of 39.6% (p=.05).

Other differences among the data were that 74% of those treated before 1998 (the early group) proceeded directly to cystectomy compared with 43% of those treated after 1998 (the late group). One-third as many patients in the early group (11%) underwent two or more intravesical treatments as did those in the late group (36%) (p=.01). More than half (57.5%) of the early group proceeded to cystectomy within 120 days of diagnosis compared with 38.2% of the late group. Time from diagnosis to cystectomy in the early group was 16.4 months compared with 23.6 months in the late group.

More therapy is ineffectual

The study authors concluded that, compared with early experience, contemporary practice in treating T1 bladder cancer involves more courses of intravesical therapy before cystectomies, but this practice does not appear to improve disease-free survival.

After Dr. Lambert presented the data at AUA, several physicians pointed out that the study lacked a denominator.

"The denominator would be all those patients who present with T1 disease," Dr. Lambert explained. "There is a large group of patients, probably more in the community than we know about, who respond to intravesical therapy. The non-responders inevitably proceed to cystectomy, and the argument is that these patients have higher-grade disease."

While she agreed that insufficient data on the overall survival rate of patients with T1 disease was a significant weakness in the study, she and other physicians attending her presentation said that they felt the study had succeeded in asking an important question.

"The only thing I could find that correlated with the decrease in disease-free survival was the increasing use of intravesical therapy. That was kind of an eye opener. But this is a retrospective study," Dr. Lambert said, adding that a prospective study would be almost impossible to perform.

She expressed the hope that other institutions with larger databases would conduct similar retrospective studies.

"Another thing to keep in mind is that when these patients go to cystectomy, approximately 30% get upgraded to T2 muscle-invasive disease. We may be waiting too long with intravesical therapies," Dr. Lambert said.

"Another is that if patients do not respond to one cycle of intravesical therapy, thought should be given to making decisions about a second cycle. Maybe [the patients'] bladders should come out or [perhaps they should] undergo radical cystectomy," she said.