Long-term effects of conservation therapy for muscle invasive bladder carcinoma
Presenter: P. Chung
Presenter's Affiliation: Princess Margaret Hospital, Toronto, ON, Canada
Type of Session: Scientific
- Cystectomy has long been considered the gold standard for treatment of muscle invasive bladder carcinoma.
- This retrospective study was undertaken to evaluate long term outcomes of radiation-based bladder conservation therapy in patients with muscle invasive bladder carcinoma.
- This was a retrospective study involving 131 patients with T2/T3aN0M0 (per 1992 AJCC guidelines) transitional cell carcinoma of the bladder managed with organ-preserving therapy at Princess Margaret Hospital betweeen 1986 and 1997.
- Response was asssessed via cystoscopy 6 weeks following the end of treatment, and salvage cystectomy was offered to patients not demonstrating a complete response. One third of relapsing patients were considered inappropriate for surgical salvage.
- 108 patients were treated with radiation alone.
- 20 patients were treated with concurrent cisplatin chemotherapy and radiation.
- 3 patients were treated with neoadjuvant chemotherapy followed by definitive radiation.
- 19 patients eventually underwent cystectomy for salvage therapy.
- Median follow-up was 4.8 years.
- Actuarial overall survival at 5 years was 44%.
- Actuarial disease-specific survival at 5 years was 58%.
- Actuarial local control at 5 years was 49%.
- For those patients demonstrating a complete response, actuarial local control at 10 years was 59%.
- Of relapsing patients, 67% failed in the bladder only, 7% failed in the bladder and pelvis, 4% failed both in the bladder and distantly, and 22% failed distantly only.
- Of patients failing in the bladder only, 52% were treated via TURBT/intravesical BCG and 31% via salvage cystectomy.
- Relapse rate was 42% at 3 years and 53% at 5 years with only 1 patient relapsing after 5 years.
- Those patients considered poor surgical candidates demonstrated significantly lower overall survival and disease-specific survival.
- Negative prognostic factors with respect to disease-specific survival and locoregional control included the presence of CIS, tumor size (>2 cm).
- Patients receiving chemotherapy demonstrated improved disease-specific survival.
- External beam radiation-based treatment results in long term organ preservation for the majority of patients with muscle-invasive transitional cell carcinoma of the bladder.
- Chemoradiation should be considered a viable alternative to surgery for the select patient population with smaller tumors and without evidence of CIS.
Bladder sparing treatment has evolved from radiation only to chemoradiation and now chemoradiation preceded by TURBT. This retrospective study demonstrates comparable survival data to past radical cystectomy trials and confirms the plausability of salvage cystectomy in patients deemed acceptable surgical candidates. However, the study fails to comment on the associated side effect profile, and it should be noted that even mild treatment-related morbidity (urgency, frequency, dysuria) can potentially result in significant decreases in quality of life. Radiation-based trials are classically skewed by the characteristics of the patient population, as patients unable to undergo cystectomy secondary to medical comorbidities often comprise a significant portion of the study population. Although a prospective study comparing cystectomy and bladder-sparing treatment would be optimal, strong biases on the part of both the physician and patient render this an unlikely scenario.
Oncolink's ASCO Coverage made possible by an unrestricted Educational Grant from Bristol-Myers Squibb Oncology.