NEW ORLEANS—Compliance with maintenance therapy for non-muscle invasive bladder cancer (NMIBC) is poor in real-world clinical practice, according to data presented at the 2015 American Urological Association (AUA) annual meeting.
In fact, compliance rates were worse than those observed in most clinical trials. The study also showed that patients tended to be more compliant with a monthly schedule than a Lamm schedule, but both protocols were associated with similar compliance rates at 1 year, suggesting that overall length of therapy drives compliance more than the difference between schedules, said Alexander M. Helfand, BA, a fourth-year medical student at the Sackler School of Medicine at Tel Aviv University in Israel and a research fellow in urology at the University of Michigan in Ann Arbor, who presented study findings.
AUA guidelines recommend that NMIBC patients at high risk for progression receive bacillus Calmette-Guérin (BCG) maintenance therapy and patients with recurrent, multifocal, or large- volume Ta low-grade malignancy receive BCG or mitomycin induction with optional maintenance. Still, in clinical trials, adherence to maintenance schedules has been poor in clinical trials. Little is known about compliance with maintenance therapy in a real-world clinical practice setting, outside the controlled environment of clinical trials, Helfand noted.
Helfand and his colleagues at Beilinson Hospital in Israel conducted a retrospective review of 729 patients in their clinic who received BCG or mitomycin for bladder cancer stage T1 or below. They defined the complete maintenance protocol as an induction of 6 weekly instillations, followed by either a Lamm schedule consisting of 3 weekly BCG instillations at 3 and 6 months after induction and every 6 months thereafter for 3 years or 9 monthly treatments starting 3 months after induction. The researchers excluded from the study patients who had disease recurrence shortly after their last treatment to prevent inclusion of patients who stopped therapy as a result of recurrence or progression. They defined compliance as receiving 9 months of monthly or 21 weeks of Lamm maintenance.
The cohort started a total of 861 induction cycles (63% with BCG and 37% with mitomycin) and received 8,247 instillations. Results showed that 54% of patients on the Lamm schedule completed at least 9 BCG instillations in the first year after induction, 26% completed 15 instillations in 2 years, and only 10% completed 3 years of treatment with 21 maintenance instillation. The 10% compliance rate was lower than that observed in most prospective trials using the 3-year maintenance protocol.
With regard to the patients undergoing monthly maintenance, patients received a median of 6.9 monthly BCG instillations or 6.6 mitomycin instillations. Helfand’s group found that 55% of patients completed 1 year of monthly maintenance, a rate similar to that observed among patients on the Lamm schedule. In addition, 47% of patients on monthly mitomycin completed 1 year of treatment.
On multivariable analysis, the only variable that predicted compliance was a prior diagnosis of bladder cancer, meaning a positive biopsy taking more than 3 months prior to the pre-induction biopsy.
Helfand noted that his group initially hypothesized that patients living greater distances from the clinic might be less compliant with treatment, but they found that this was not the case.