Five-year follow-up of health-related quality of life after intensity-modulated radiation therapy for prostate cancer.

OBJECTIVE We evaluated health-related quality of life (HRQOL) in patients with localized prostate cancer who underwent intensity-modulated radiation therapy (IMRT) or three-field conformal radiotherapy (3DCRT). METHODS A total of 97 patients underwent 3DCRT and 36 underwent IMRT for localized prostate cancer between 2002 and 2004. We measured the general and disease-specific HRQOL with the Medical Outcomes Study 36-Item Health Survey and University of California, Los Angeles Prostate Cancer Index, respectively. RESULTS There were no significant differences in the pre-operative characteristics of the two groups. The patients in the 3DCRT group were more likely to receive hormonal therapy compared with the IMRT group before and after radiation therapy (P < 0.001 and P = 0.011, respectively). With regard to general HRQOL domains, both the 3DCRT and IMRT group scores showed no significant difference between baseline and any of the observation periods. At 60 months after treatment, the 3DCRT group had significantly worse bowel function and bother scores than baseline (both P < 0.001). On the other hand, there were no significant differences between the baseline and any of the post-treatment time periods in the IMRT group. In the 3DCRT group, sexual function remained substantially lower than the baseline level (P = 0.023). The IMRT group tended to show a decrease in sexual function, which was not statistically significant (P = 0.11). CONCLUSIONS IMRT can provide the possibility to deliver a high irradiation dose to the prostate with satisfactory functional outcomes for long-term periods.