Radiation therapy for prostate cancer can cause erectile dysfunction (ED). Intensity Modulated Radiation Therapy (IMRT) can reduce the amount of radiation to surrounding tissues associated with ED. We characterize the incidence of and factors associated with ED in prostate cancer patients after IMRT at the National Naval Medical Center (NNMC). Patients potent by definition of the Sexual Health Inventory for Men (SHIM) before treatment completed the specific erectile questions of the SHIM after IMRT. Statistical analyses were performed to examine the relationships between several factors and ED. Thirty-two of 45 patients with mean age of 68.2 years (50-86 years) completed the SHIM. The median follow-up was 36.8 months (16-63.6 months) as defined by the time from completion of therapy to reassessment with the SHIM. Eight of 32 patients (25%) had no post-treatment ED (SHIM score 22-25), three of 32 (9%) had mild post-treatment ED (SHIM score 17-21), five of 32 (16%) had mild to moderate ED (SHIM score 12-16), five of 32 (16%) had moderate ED (SHIM score 8-11) and 11 of 32 (34%) had severe post-treatment ED (SHIM scoreo8). Posttreatment potency was significantly associated with the pre-treatment SHIM score (P ¼ 0.001) and history of hypertension (P ¼ 0.03). The mean radiation dose to the penile bulb and volume of penile bulb treated were not associated with post-treatment potency (P ¼ 0.38, 0.76, respectively). IMRT maintains potency in the majority of patients. This analysis compares favorably in preserving erectile function to previously reported series using conventional external beam radiation therapy techniques. The dose of radiation received by the penile bulb and volume of penile bulb were not associated with post-treatment ED in this analysis.
SRT results in durable prostate specific antigen control in select patients. It is well tolerated with few severe late effects. Increasing Gleason score, lymphovascular invasion and lack of a complete response to SRT are significant risks for disease progression requiring additional management.
BACKGROUNDLymphovascular invasion (LVI) is found in approximately 5% to 53% of specimens after radical prostatectomy (RP). Although LVI is associated with higher rates of recurrence after RP, its prognostic significance after postprostatectomy radiotherapy (P‐XRT) is unclear.METHODSThe medical records of men who received P‐XRT from 1991 to 2001 at 2 institutions were reviewed for the presence of LVI in RP specimens. Multiple patient variables were evaluated for their association with LVI using Fisher exact tests and Wilcoxon rank‐sum tests. The time to biochemical recurrence (BCR) and the time to distant metastases (DM) after RP were analyzed using Kaplan–Meier estimations, log‐rank tests, and Cox regression analyses.RESULTSEighteen of 160 patients (11%) who received P‐XRT had LVI in their RP specimen. High Gleason score and seminal vesicle invasion were associated significantly with LVI. After a median follow‐up of 8.3 years after RP, 16 patients with LVI had BCR after P‐XRT, 9 of whom developed DM. The median time to BCR in patients with LVI was 2.6 years (95% confidence interval [95% CI], 1.8‐5.4) compared with 7.8 years (95% CI, 6.8‐10.3) in patients without LVI (P < .001). Multivariate analysis revealed an adjusted relative risk for LVI of 5.5 (P < .001). Other significant factors were Gleason score, undetectable post‐RP serum prostate‐specific antigen (PSA) levels, preradiotherapy serum PSA levels, and the interval from RP to P‐XRT. LVI was the only significant factor associated with an increased risk of DM in univariate analysis (hazard ratio, 7.4; P < .001).CONCLUSIONSLVI was useful as a pathologic marker for reduced efficacy of P‐XRT after RP in terms of increased risk of BCR and DM. Future studies will be needed to validate these findings. Cancer 2006. Published 2006 American Cancer Society.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.