Morbidity and Mortality of Locally Advanced Prostate Cancer: A Population Based Analysis Comparing Radical Prostatectomy versus External Beam Radiation

Abstract

Purpose: The management of locally advanced prostate cancer remains controversial. We compared the effect of primary external beam radiation therapy vs radical prostatectomy for locally advanced prostate cancer.

Materials and methods: We retrospectively analyzed the records of 2,935 elderly men 65 years old or older in the SEER (Surveillance, Epidemiology and End Results)-Medicare linked database who underwent external beam radiation therapy or radical prostatectomy for locally advanced prostate cancer. Propensity adjusted Cox proportional hazard and regression models were fit to examine urinary and gastrointestinal toxicities, the use of androgen deprivation therapy, and overall and prostate cancer specific mortality.

Results: A total of 1,429 men (48.69%) underwent radical prostatectomy and had a median followup of 11.47 years (IQR 6.17-17.17) years. A total of 1,506 men (51.31%) received external beam radiation therapy and had a median followup of 7.04 years (IQR 4.11-10.51, p <0.001). Patients treated with radical prostatectomy were at significantly higher risk for urinary and sexual toxicities (HR 1.93, 95% CI 1.66-2.24 and HR 5.50, 95% CI 3.59-8.42, respectively). However, they were at lower risk for gastrointestinal toxicities (HR 0.75, 95% CI 0.65-0.86) than those treated with external beam radiation therapy. Radical prostatectomy was associated with lower odds of androgen deprivation therapy 5 years after primary treatment (OR 0.53, 95% CI 0.41-0.69, p <0.001). External beam radiation therapy was associated with higher overall and prostate specific mortality (HR 1.41, 95% CI 1.09-1.82 and HR 2.35, 95% CI 1.85-2.98, respectively).

Conclusions: We found significant toxicity and survival differences in elderly men who underwent primary external beam radiation therapy vs radical prostatectomy for locally advanced prostate cancer. While our findings must be interpreted within the limitations of studies that rely on administrative claims, they may yet help tailor individual therapies for elderly men who present with locally advanced prostate cancer.

Keywords: mortality; prostatectomy; prostatic neoplasms; radiotherapy; toxicity.