Biochemical disease-free survival in men younger than 60 years with prostate cancer treated with external beam radiation

Abstract

Purpose: We determined the biochemical failure rate in patients 60 years and younger, and older than 60 years old who were treated with external beam radiation for localized prostate cancer or locally advanced prostate cancer. We also evaluated prognostic factors in the 2 age groups.

Materials and methods: We reviewed the medical records of 964 patients who received full dose radiotherapy as the only treatment for prostate cancer. Followup prostate specific antigen was measured 3 to 6 months after the completion of radiotherapy and every 3 to 6 months thereafter. Biochemical failure was defined using the criteria established by the American Society for Therapeutic Radiology and Oncology Consensus Panel. Median followup in the whole study group was 48 months.

Results: Of the 98 men 60 years or younger 46 (47%) had biochemical failure, whereas 261 (30%) of the 866 older than 60 years old had biochemical failure. The 5 and 7-year biochemical disease-free survival rates were 55% and 47% in the younger men, and 65% and 59% in the older men, respectively. These rates were significantly lower in the younger men (p = 0.017 and 0.027, respectively). Multivariate regression showed that in men 60 years or younger initial prostate specific antigen, Gleason score and lower radiation doses were predictive of biochemical failure.

Conclusions: Men with prostate cancer who are 60 years or younger and treated with radiotherapy may be at significant risk for long-term biochemical failure.