Prostate Cancer Radiotherapy: Increased Biochemical Control and Late Toxicity in Men With Medication Allergies

Abstract

Background Given similarities in the mediators of medication allergy (MA) and tissue response to radiotherapy, we assessed whether outcomes following prostate radiotherapy differ in patients with MAs. Methods 587 men with known MA history and non-metastatic prostate cancer underwent radiotherapy from 1989-2006. Clinicopathologic and treatment variables were analyzed for association with freedom from biochemical failure (FFBF) and late treatment-related, physician-defined Radiation Therapy Oncology Group gastrointestinal (GI) and genitourinary (GU) toxicity. Covariates identified on univariate analysis (UVA) for toxicity and disease control were examined on multivariable analysis (MVA). All statistical tests were two-sided and a P < .05 was considered statistically significant. Results 155 of 587 men (26.4%) had one or more MAs, most commonly to penicillin (n = 71), sulfa (n = 35) and aspirin/NSAIDs (n = 28). On UVA, men with MA had superior 10-y FFBF (71.5% vs. 63.5%, P = .02) and higher incidence of late GI grade 2 + (G2+; 20.6% vs. 13.2%, P = .04) and grade 3 + (G3+; 7.5% vs. 3.9%, P = .08), as well as late GU G2 + (42.5% vs. 33.2%, P = .04) and G3 + (7.5% vs. 3.0%, P = .02) toxicity than men without MA. On MVA, MA history remained a statistically significant predictor of FFBF (HR = 0.64 [95% CI = 0.43 to 0.93]; P = .02), late G2+ GI (HR = 1.76 [95% CI = 1.06 to 2.90]; P = .03) and G3+ GU (HR = 2.69 [95% CI = 1.16 to 6.27]; P = .02) toxicity after controlling for corresponding covariates in each model. Conclusions Men with MA had improved FFBF and increased treatment-related toxicity following radiotherapy for prostate cancer. MA history could be a relevant consideration in the management of men with localized prostate cancer.

Hematuria following Post-Prostatectomy Radiotherapy: Incidence Increases with Long-Term Followup

“…14 AC/AP may increase gross hematuria by making subclinical hematuria more readily apparent or by enhancing radiation-induced adaptive immune response. 21,22 As previously reported in men treated with primary prostate radiotherapy, 23 men with MA were more likely to develop hematuria following PPRT. Increased rates of hematuria among men with MA may result from a lower threshold to mount T-cell-mediated immune responses resulting in increased propensity for depletion of stromal stem cells following PPRT 24 and increased post-treatment expression of transforming growth factor beta (TGF-β).…”