Erectile function after permanent 125I prostate brachytherapy for localized prostate cancer

Background and purpose
To analyze erectile function in men treated by prostate brachytherapy (PB) for localized prostate cancer.

Material and methods
Of a series of 270 sexually active men treated by PB, 241 (89%), mean age 65 yr (range, 43–80 yr), participated in a study on erectile function that was evaluated using the International Index of Erectile Function 5-item (IIEF-5) questionnaire before implantation and by postal survey after a mean follow-up of 36 months (range, 6–70 months).

Results
After PB, 27 patients (11%) had no erectile dysfunction (ED), 36 (15%) had mild ED, 58 (24%) had mild to moderate ED, 24 (10%) had moderate ED, 53 (22%) had severe ED and 43 (18%) were not sexually active. In patients with a preimplant IIEF score >12 (cut-off for intercourse with penetration), 73% had a deterioration of erectile function by at least one class after PB. Risk factors for ED after PB were age, preimplant IIEF score and prostate volume. Median time to ED onset was 16 months and was shorter with androgen deprivation (p = 0.007), diabetes (p = 0.03) and age over 55 (p = 0.01).

Conclusions
Following PB, the majority of patients progressively develop or major ED after a free interval that may last several months.