According to a recent article published in Lancet Oncology, the combination of BCG plus electromotive mitomycin C improves outcomes compared to BCG alone in the treatment of superficial bladder cancer.
Bladder cancer is a common cancer; approximately 55,000 new cases are diagnosed in the U.S. each year. Superficial bladder cancer refers to cancer that remains localized within the outermost (most superficial) layers of the bladder and has not spread to deeper layers. Patients with superficial bladder cancer are routinely treated with surgical removal of the cancer and adjuvant therapy to decrease the risk of cancer recurrence or progression to more invasive disease.
Despite standard treatment, many patients with superficial bladder cancer experience recurrence of their cancer. Following the removal of the cancer, patients with superficial bladder cancer are usually treated with adjuvant intravesical therapy (placement of the drug directly into the bladder). This often consists of mitomycin C or Bacille Calmette-Guérin (BCG). BCG, an immunotherapy agent, is derived from a weakened form of a bacterium related to bacteria that cause tuberculosis.
While this therapy is beneficial, recurrences are common. Researchers are evaluating ways to enhance the effectiveness of intravesical therapy to reduce the risk of recurrences in patients with superficial bladder cancer.
Researchers from Italy recently conducted a clinical trial to evaluate different intravesical treatments for patients with superficial bladder cancer who had undergone the surgical removal of their cancer. This trial included 211 patients. Approximately were treated with BCG once per week for 6 weeks, while remaining patients received BCG once per week for 2 weeks followed by intravesical electromotive mitomycin C (chemotherapy assisted with electric current to stimulate the passage of the agent through the tissues) once per week for 3 weeks.
At a median follow-up of 88 months, patients treated with BCG plus electromotive mitomycin C had significantly improved outcomes compared to those treated with BCG alone:
- Cancer-free interval following therapy was 69 months for those treated with BCG/mitomycin C, compared with 21 months for those treated with BCG only-a difference of 4 years.
- Cancer recurrences occurred in 41.9% of patients who underwent BCG/mitomycin C and in 57.9% of patients who underwent BCG treatment only.
- Cancer progression occurred in 9.3% of patients treated with BCG/mitomycin C and 21.9% of patients treated with BCG only.
- Overall mortality was 21.5% in patients treated with BCG/mitomycin C, compared with 32.4% for those treated with BCG only.
- Mortality caused by bladder cancer occurred in only 5.6% of patients treated with BCG/mitomycin C, compared with 16.2% of patients treated with BCG only.
- Side effects primarily remained localized to the bladder.
The researchers concluded that the combination of BCG and electromotive mitomycin C provides superior results to BCG alone in the treatment of superficial bladder cancer, including mortality caused by bladder cancer. The researchers state that the initial infusion of BCG may allow greater permeation of mitomycin C into the tissues of the bladder.
Reference: Stasi S, Giannantoni A, Giurioli A, et al. Sequential BCG and electromotive mitomycin versus BCG alone for high-risk superficial bladder cancer: a randomized controlled trial. Lancet Oncology. 2006; 7: 43-51.