Acute and late genitourinary toxicity of conformal radiotherapy for prostate cancer.
OBJECTIVE
The aim of this study was to identify predictive factors for genitourinary (GU) toxicity in prostate cancer patients who underwent conformal radiotherapy (CRT).


METHODS
In this study we analyzed 154 cases of T1-3N0M0 prostate adenocarcinoma and evaluated the occurrence rate of acute and late GU toxicity and the duration of acute toxicity according to clinical parameters: age, transurethral resection of the prostate prior to CRT, hormone therapy, CRT dose, length of planning target volume (PTV).


RESULTS
Altogether, 41% of the patients developed grade 2 or higher acute GU toxicity. Longer PTV was significantly associated with a higher incidence of acute GU toxicity (>7 cm, 53%; <or=7 cm, 31%; P = 0.003), and hormone therapy prolonged the duration of the toxicity (P = 0.007). Grade 1 or higher late GU toxicity developed in 23% of the patients, and the 2-year late GU toxicity-free survival rate was 79%. Acute GU toxicity was significantly associated with the late GU toxicity-free survival rate (grade 0-1, 88.7%; grade 2-4, 73.2%; P = 0.0007).


CONCLUSIONS
The length of PTV and hormone therapy were predictive factors for acute GU toxicity. Furthermore, acute GU toxicity was the most important predictive factor for late GU toxicity.
Yoshimura
Ryo-ichi
R
Department of Radiology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan. ysmrmrad@tmd.ac.jp
Iwata
Masaru
M
Shibuya
Hitoshi
H
Sakai
Yasuyuki
Y
Kihara
Kazunori
K
D000208:Acute Disease; D000230:Adenocarcinoma / Q000473:pathology / Q000532:radiotherapy*; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D018572:Disease-Free Survival; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D052801:Male Urogenital Diseases / Q000453:epidemiology / Q000209:etiology*; D008875:Middle Aged; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D020266:Radiotherapy, Conformal / Q000009:adverse effects*; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome; D047368:Tumor Burden / Q000528:radiation effects; D014555:Urination Disorders / Q000453:epidemiology / Q000209:etiology; D014566:Urogenital System / Q000528:radiation effects