Comparing the rates of urinary tract infections among patients receiving adjuvant pelvic intensity modulated radiation therapy, 3-dimensional conformal radiation therapy, and brachytherapy for newly diagnosed endometrial cancer

Abstract

PurposeThe purpose of this study was to compare the rates of urinary tract infection (UTI) among patients with endometrial cancer receiving vaginal brachytherapy alone and brachytherapy plus 3-dimensional conformal radiation therapy (3DCRT) or intensity modulated radiation therapy (IMRT). Methods and MaterialsWe retrospectively evaluated the rates of UTI among 581 patients diagnosed with endometrial cancer, treated between 2004 and 2012. A total of 37% (216/581) received brachytherapy alone, 28% (161/581) received brachytherapy plus 3DCRT, and 35% (204/581) received brachytherapy plus IMRT. UTI during the treatment was defined as evidence of pyuria detected by either urine dipstick or urinalysis. All specimens were collected as a clean catch, midstream void to avoid contamination and resultant false positives. The χ2 and logistic regression analyses were subsequently employed for statistical analyses. ResultsUTI was diagnosed in 14.6% (85/581) of all patients. Only 2.8% (6/216) of patients receiving brachytherapy were diagnosed with a UTI during treatment, whereas UTI was diagnosed in 37.3% (60/161) of patients receiving brachytherapy plus 3DCRT, and 9.3% (19/204) of patients receiving brachytherapy plus IMRT (P < .0005). Logistic regression analysis found a decreased association between UTI and stage III endometrial cancer (odds ratio [OR], 0.51, 95% confidence interval [CI], 0.26, 0.99; P = .048). When compared with brachytherapy, both types of external beam radiation therapy were associated with an increased risk of UTI, though adjuvant 3DCRT (OR, 47.52, 95% CI, 14.81, 152.47; P < .001) had a more dramatic risk increase than IMRT (7.89, 95% CI, 2.26, 27.62; P = .001). ConclusionsWhen compared with IMRT, 3DCRT is associated with a significantly increased risk of UTI, supporting the use of IMRT as the less toxic external beam radiation therapy for endometrial cancer.