Klin Onkol 2002; 15(2): 58-63.
Summary:
Background and Purpose: Three-dimensional conformal radiotherapy (3D-CRT) is an effective method in the management of various neoplasms. We evaluated the incidence and predictors of acute toxicity in patients treated with 3DCRT for localized prostate cancer.
Materials and Methods: Between December 1997 and November 1999, 102 consecutive patients with T1-T3 prostatic carcinoma were treated using 3D-CRT. 81 patients were treated with a dose of 70 Gy (ICRU), while 21 patients with T3 tumors received 74 Gy. The clinical target volume (CTV) included prostate and the base of seminal vesicles (T1, T2) or prostate and the entire seminal vesicles (T3). A circumferential margin of 10 mm (15 mm superiorly and inferiorly) was added to CTV to create the planning target volume (PTV). The treatment fields were individually shaped usány a multileaf collimator. Acute gastrointestinal (GI) and genitourinary (GU) toxicity was graded according to EORTC/RTOG scoring system. Symptoms duration after the completion of radiotherapy (<4 weeks vs. ≥4 weeks) was recorded. The correlation between dose-volume histogram (DVH) parameters and the observed acute toxicity was investigated.
Results: The majority of patients experienced no or only mild (Grade 1) acute toxicity symptoms. Medication for GI and GU symptoms (Grade 2) was required by 29/102 (28.4%) and 12/102 (11.8%) of patients, respectively. Only one case of Grade 3 GI toxicity (1.0%) was observed. There were 6/102 (5.9%) of patients with severe (Grade 3 and 4) GU toxicity. No relationship was seen between the incidence and severity of the acute toxicity and age, stage, dose (70 Gy vs. 74 Gy), prior invasive procedure (transurethral resection of the prostate TURP, transvesical prostatectomy for benign prostatic hyperplasia TVPE), and pelvic lymphadenectomy. Moreover, no significant differences were recorded between DVH parameters and acute toxicity. There was a strong relationship between the duration of acute GU toxicity and prior invasive procedure (TURP or TVPE). Symptoms persisted more than 4 weeks in 48.0% of patients with a positive history compared to 26.0% of patients with a negative history (p=0.03). The interval between TURP/TVPE and the start of radiotherapy had no impact on GU toxicity.
Conclusions: The incidence of severe acute complications was acceptable in our cohort of patients. A history of invasive procedure (TURP or TVPE) was associated with prolonged acute genitourinary toxicity.
