Faculty Bibliography

The American Urological Association Best Practice Policy states that although pelvic lymph node dissection (PLND) is commonly done with radical prostatectomy, its morbidity must be considered, particularly in cases in which it offers little additional information. The benefits of PLND include more accurate staging and reassurance for the patient. In addition, PLND may be therapeutic for men with lymph node metastases and may result in long-term biochemical cure for selected node-positive patients. However, the incidence of node positivity is declining, and accordingly a greater number of lymphadenectomies must be performed to benefit 1 patient. In addition to the associated cost, PLND has the potential for morbidity, including lymphoceles, thromboembolic events, ureteral injury, and neurovascular injury. Patients and physicians should therefore assess the risk/benefit ratio associated with PLND on an individual basis to permit informed treatment decisions.

BACKGROUND: Radical cystoprostatectomy (RCP) remains the gold standard for the treatment of muscle-invasive bladder cancer. There are limited data regarding the clinical impact and detection of PSA following complete prostatectomy or the need to monitor serum PSA in patients with benign prostate pathology at time of RCP. The purpose of our study was to analyze the postoperative PSA characteristics of men without prostate cancer who underwent a RCP for bladder cancer. METHODS: The demographic, clinical and pathologic data were reviewed on 138 men who underwent RCP for bladder cancer from 1994 to 2008. Patients with known or incidentally discovered prostate cancer on final pathology were excluded from this study, and postoperative serum PSA values were reviewed in the remaining men. RESULTS: The median age of the study population was 64 years (range 40-84). At a mean follow-up of 40.7 months, 137 (99.3%) of patients had an undetectable serum PSA. The one (0.7%) case in which serum PSA was not undetectable underwent an apex-sparing prostatectomy at the time of cystectomy. CONCLUSIONS: Serum PSA should remain undetectable for men with benign prostate pathology undergoing complete prostatectomy at the time of RCP. Elevated serum PSA following complete RCP in men with bladder cancer and pathologically confirmed benign prostate findings is rare. If the serum PSA is undetectable 3 months after RCP with benign prostate pathology, there is no need for continued PSA monitoring. These data support the notion that potential nonprostatic sources of PSA are clinically insignificant following complete removal of the prostate.

PURPOSE: Obesity may be associated with lower prostate specific antigen through hemodilution. We examined the relationship between body mass index and prostate specific antigen by age in men without prostate cancer in a longitudinal aging study to determine whether prostate specific antigen must be adjusted for body mass index. MATERIALS AND METHODS: The study population included 994 men (4,937 observations) without prostate cancer in the Baltimore Longitudinal Study of Aging. Mixed effects models were used to examine the relationship between prostate specific antigen and body mass index in kg/m(2) by age. Separate models were explored in men with prostate cancer censored at diagnosis, for percent body fat measurements, for weight changes with time and adjusting for initial prostate size in 483 men (2,523 observations) with pelvic magnetic resonance imaging measurements. RESULTS: In men without prostate cancer body mass index was not significantly associated with prostate specific antigen after adjusting for age (p = 0.06). A 10-point body mass index increase was associated with a prostate specific antigen difference of -0.03 ng/ml (95% CI -0.40-0.49). Results were similar when men with prostate cancer were included, when percent body fat was substituted for body mass index, and after adjusting for prostate volume. Longitudinal weight changes also had no significant association with prostate specific antigen. CONCLUSIONS: Consistent with prior studies, we found an inverse relationship between obesity and serum prostate specific antigen. However, the magnitude of the difference was small. Thus, adjusting prostate specific antigen for body mass index does not appear warranted.

OBJECTIVE: To examine further the relationship between diabetes mellitus (DM), genotype and prostate cancer aggressiveness. Specifically, we sought to evaluate for effect modification between DM, a newly discovered prostate cancer susceptibility locus on chromosome 17q12 (single nucleotide polymorphism rs4430796) and prostate cancer features. PATIENTS AND METHODS: In 593 genotyped men treated with radical prostatectomy (RP), we examined RP features stratified by DM and rs4430796 carrier status. RESULTS: Despite a significantly higher body mass index among patients with DM, individual pathological features were similar between men with and without DM. Using a dominant model, 17q12 carriers were less likely to have DM and more likely to have a RP Gleason score of >or=7. However, the presence or absence of DM did not modify the relationship between 17q12 susceptibility alleles and pathological features. CONCLUSION: Among 17q12 risk allele carriers, there was no significant relationship between DM and adverse tumour features. However, there were relatively few men with DM (7%) in our RP cohort, particularly compared with its 21% prevalence in the USA population aged >60 years. It is unclear whether this reflects selection bias, genetic protection from prostate cancer among patients with DM, or both. Despite these limitations, the present data suggest that DM alone does not appear to modify any association between 17q12 risk alleles with prostate cancer features.

PURPOSE: According to a 1944 publication by Swyer benign prostatic hyperplasia develops in some men after age 45 with further prostatic growth whereas in other men prostate size remains stable or decreases with advancing age. Although there is an abundance of literature describing prostatic enlargement in association with benign prostatic hyperplasia, less is known about the phenomenon of prostate atrophy. MATERIALS AND METHODS: In the Baltimore Longitudinal Study of Aging serial pelvic magnetic resonance imaging was performed in men without prostate cancer beginning in 1993. From this population we retrospectively identified 278 men with 2 or more magnetic resonance imaging determined prostate volume measurements to examine differential growth rates in a cohort of community men over time. RESULTS: Median age was 58 years and median prostate size was 28 cc at study entry. At a median followup of 4.3 years prostate size increased in 61.9% and remained stable or decreased in 38.1% of men. The median rate of volume change was 0.6 cc per year (range -9.9 to 62.1), corresponding to a median growth rate of 2.5% per year (range -29.2 to 176.4%). During followup 64.6% of men with an initial prostate size less than 40 cc had prostate growth compared to only 50.9% of men with an initial prostate size of 40 cc or greater. CONCLUSIONS: These results suggest that changes in prostate size are highly variable among aging men. Although benign prostatic hyperplasia is common, a considerable proportion of aging men have a stable or decreasing prostate size. Further research is needed to identify the underlying mechanism for such differences in prostate growth.