A retrospective long-term comparison of three prostate cancer treatment strategies revealed that treatment with external beam radiation therapy (EBRT) resulted in more long-term toxicities and higher treatment-related costs than prostatectomy and brachytherapy.
"External beam is the most toxic and the most costly," said first author Jay P. Ciezki, MD, staff physician in Cleveland Clinic's radiation oncology department. "The average cost per patient-year for the external beam was more than twice as expensive as its nearest competitor, prostatectomy."
The authors mined the Surveillance, Epidemiology, and End Results Medicare database for information from between 1991 and 2007 regarding prostate cancer patients treated with EBRT, prostatectomy, or brachytherapy. Procedural billing codes associated with treatment-related toxicity were identified, and information on the Medicare reimbursement rates for the initial treatment and toxicity-related interventions was obtained.
The median follow-up was 71 months, with a potential for follow-up as long as 16 years. Patients included had prostate cancer as their only cancer diagnosis. The database uncovered 137,427 patients 65 years of age and older at the time of their prostate cancer diagnosis. Forty-three percent were treated with prostatectomy, 44.2% with EBRT, and 12.4% with brachytherapy. None of the patients received combined therapy. Overall, 7.3% of patients required an intervention for a therapy-related side effect.
Brachytherapy had the lowest average cost per patient-year at $2,557.36. Prostatectomy was slightly more expensive, at $3,205.71. Most expensive was EBRT, at $6,412.29.
Treatment-related toxicities were most common with EBRT, with an incidence of 8.8%, compared with 6.9% for prostatectomy and 3.7% for brachytherapy.
Some 7.1% of patients receiving EBRT experienced genitourinary toxicity, compared with 6.7% of those treated with prostatectomy and 3.4% of those treated with brachytherapy. The most common genitourinary toxicity was urethral stricture (3.6% of all patients). At 15 years, the rate of genitourinary toxicity was 5% to 6% with prostatectomy and 12% to 13% with EBRT.
Cauterization of rectal bleeding was the most common intervention for gastrointestinal side effects (0.8% of all patients).
"Well over 50% of the patients who had any GI toxicity expressed that with GI bleeding, usually rectal bleeding," said Dr. Ciezki.