We conducted a retrospective review of all patients with localized prostate cancer who received external-beam radiotherapy (EBRT) in combination with brachytherapy with at least 1 year follow-up (n = 812). Combination therapy consisted of 103Pd or 125I implant, followed by a course of EBRT. From 1993 to March 2003 521 patients were treated with 3D-CRT, and from April 2003 to March 2009 291 patients were treated with IMRT. Urinary symptoms were prospectively measured with the International Prostate Symptom Score questionnaire with a single quality of life (QOL) question; rectal bleeding was assessed per the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring Schema. The Pearson ¦Ö2 test was used to compare toxicities experienced by patients who were treated with either IMRT or 3D-CRT. Logistic regression analyses were also performed to rule out possible confounding factors.
Within the first 3 months after treatment, patients treated with 3D-CRT scored their urinary symptoms as follows: 19 % mild, 44 % moderate, and 37 % severe; patients treated with IMRT scored their urinary symptoms as follows: 36 % mild, 47 % moderate, and 17 % severe (p?< 0.001). The 3D-CRT patients rated their QOL as follows: 35 % positive, 20 % neutral, and 45 % negative; IMRT patients rated their QOL as follows: 51 % positive, 18 % neutral, and 31 % negative (p < 0.001). After 1 year of follow-up there was no longer any difference in urinary morbidity between the two groups. Logistic regression confirmed the differences in International Prostate Symptom Score and QOL in the acute setting (p < 0.001 for both). Grade ? rectal bleeding was reported by 11 % of 3D-CRT patients and 7 % of IMRT patients (p = 0.046); logistic regression analysis also confirmed this observation (p = 0.040).
When used in combination with brachytherapy, IMRT offers less Grade ? rectal bleeding, less acute urinary toxicities, and is associated with a higher QOL compared with 3D-CRT.