Race and time from diagnosis to radical prostatectomy: does equal access mean equal timely access to the operating room?--Results from the SEARCH database

BACKGROUND

African American men with prostate cancer are at higher risk for cancer-specific death than Caucasian men. We determine whether significant delays in management contribute to this disparity. We hypothesize that in an equal-access health care system, time interval from diagnosis to treatment would not differ by race.

METHODS

We identified 1,532 African American and Caucasian men who underwent radical prostatectomy (RP) from 1988 to 2007 at one of four Veterans Affairs Medical Centers that comprise the Shared Equal-Access Regional Cancer Hospital (SEARCH) database with known biopsy date. We compared time from biopsy to RP between racial groups using linear regression adjusting for demographic and clinical variables. We analyzed risk of potential clinically relevant delays by determining odds of delays >90 and >180 days.

RESULTS

Median time interval from diagnosis to RP was 76 and 68 days for African Americans and Caucasian men, respectively (P = 0.004). After controlling for demographic and clinical variables, race was not associated with the time interval between diagnosis and RP (P = 0.09). Furthermore, race was not associated with increased risk of delays >90 (P = 0.45) or >180 days (P = 0.31).

CONCLUSIONS

In a cohort of men undergoing RP in an equal-access setting, there was no significant difference between racial groups with regard to time interval from diagnosis to RP. Thus, equal-access includes equal timely access to the operating room. Given our previous finding of poorer outcomes among African Americans, treatment delays do not seem to explain these observations. Our findings need to be confirmed in patients electing other treatment modalities and in other practice settings.

Structural heterogeneity and protein composition of exosome-like vesicles (prostasomes) in human semen

BACKGROUND

Human seminal fluid contains small exosome-like vesicles called prostasomes. Prostasomes have been reported previously to play an important role in the process of fertilization by boosting survivability and motility of spermatozoa, in addition to modulating acrosomal reactivity. Prostasomes have also been reported to present with sizes varying from 50 to 500 nm and to have multilayered lipid membranes; however, the fine morphology of prostasomes has never been studied in detail.

METHODS

Sucrose gradient-purified prostasomes were visualized by cryo-electron microscopy (EM). Protein composition was studied by trypsin in-gel digestion and liquid chromatography/mass spectrometry.

RESULTS

Here we report for the first time the detailed structure of seminal prostasomes by cryo-EM. There are at least three distinct dominant structural types of vesicles present. In parallel with the structural analysis, we have carried out a detailed proteomic analysis of prostasomes, which led to the identification of 440 proteins. This is nearly triple the number of proteins identified to date for these unique particles and a number of the proteins identified previously were cross-validated in our study.

CONCLUSION

From the data reported herein, we hypothesize that the structural heterogeneity of the exosome-like particles in human semen reflects their functional diversity. Our detailed proteomic analysis provided a list of candidate proteins for future structural and functional studies.

Do nomograms predict aggressive recurrence after radical prostatectomy more accurately than biochemical recurrence alone?

OBJECTIVE

To compare the predictive accuracy (PA) of existing models in estimating risk of biochemical recurrence (BCR) vs aggressive recurrence (BCR with a prostate-specific antigen, PSA, doubling time, DT, of <9 months).

PATIENTS AND METHODS

The study included 1550 men treated with radical prostatectomy (RP) between 1988 and 2007 within the Shared Equal Access Regional Cancer Hospital database. The PA of nine different risk stratification models for estimating risk of BCR and risk of aggressive recurrence after RP was assessed using the concordance index, c.

RESULTS

The 10-year risks of BCR and aggressive recurrence were 47% and 9%, respectively. Across all nine models tested, the PA was a mean (range) of 0.054 (0.024-0.074) points higher for predicting aggressive recurrence than for predicting BCR alone (c = 0.756 vs 0.702). Similar results were obtained in four sensitivity analyses: (i) defining patients with BCR but unavailable PSADT (220) as having aggressive recurrence; (ii) defining these patients as not having aggressive recurrence; (iii) defining aggressive recurrence as a PSADT of <6 months; or (iv) defining aggressive recurrence as a PSADT of <12 months. The improvement in PA was greater for preoperative than for postoperative models (0.053 vs 0.036, P = 0.03).

CONCLUSION

Across nine different models the prediction of aggressive recurrence after RP was more accurate than the prediction of BCR alone. This is probably because current models mainly assess cancer biology, which correlates better with aggressive recurrence than with BCR alone. Overall, all models had relatively similar accuracy for predicting aggressive recurrence.

What are the factors associated with short prostate specific antigen doubling time after radical prostatectomy? A report from the SEARCH database group

PURPOSE

Short prostate specific antigen doubling time following recurrence after radical prostatectomy portends a poor prognosis in men with prostate cancer. We determined which demographic and clinicopathological variables were predictive of a short prostate specific antigen doubling time in a cohort of men with clinically localized prostate cancer treated with radical prostatectomy.

MATERIALS AND METHODS

Data on 856 men from the Shared Equal Access Regional Cancer Hospital database who underwent radical prostatectomy for node negative prostate cancer between 1988 and 2003 were included in the analysis. We used logistic regression analysis to determine the independent factors associated with a short prostate specific antigen doubling time of less than 9 months vs a longer doubling time of 9 months or greater, or no recurrence. The variables analyzed were patient age, race, logarithmically transformed preoperative prostate specific antigen, body mass index, year of surgery, pathological Gleason sum, extraprostatic extension, surgical margin status and seminal vesicle invasion.

RESULTS

On multivariate analysis higher preoperative prostate specific antigen (OR 2.20, 95% CI 1.52-3.19, p <0.001), pathological Gleason sum 8-10 (OR 4.70, 95% CI 2.11-10.43, p <0.001) and 7 (OR 2.11, 95% CI 1.09-4.08, p = 0.026), tumors with extraprostatic extension and/or positive surgical margins (OR 2.08, 95% CI 1.48-3.91, p = 0.023), and seminal vesicle invasion (OR 3.26, 95% CI 1.48-7.21, p = 0.003) were independent predictors of a short prostate specific antigen doubling time. Based on these risk factors we developed a table to estimate the risk of recurrence with a prostate specific antigen doubling time of less than 9 months.

CONCLUSIONS

The factors that are invariably used to predict overall biochemical recurrence following radical prostatectomy, including high prostate specific antigen, high grade and adverse pathological findings, also predict aggressive recurrence.

The association between prostate size and Gleason score upgrading depends on the number of biopsy cores obtained: results from the Shared Equal Access Regional Cancer Hospital Database

OBJECTIVE

To test the hypothesis that the association between prostate size and risk of Gleason grade upgrading varies as a function of sampling.

PATIENTS AND METHODS

We examined the association between pathological prostate weight, prostate biopsy scheme and Gleason upgrading (Gleason > or =7 at radical prostatectomy, RP) among 646 men with biopsy Gleason 2-6 disease treated with RP between 1995 and 2007 within the Shared Equal Access Regional Cancer Hospital Database using logistic regression. In all, 204 and 442 men had a sextant (six or seven cores) or extended-core biopsy (eight or more cores), respectively. Analyses were adjusted for centre, age, surgery, preoperative prostate-specific antigen level, clinical stage, body mass index, race, and percentage of cores positive for cancer.

RESULTS

In all, 281 men (44%) were upgraded; a smaller prostate was positively associated with the risk of upgrading in men who had an extended-core biopsy (P < 0.001), but not among men who had a sextant biopsy (P = 0.22). The interaction between biopsy scheme and prostate size was significant (P interaction = 0.01).

CONCLUSIONS

These data support the hypothesis that the risk of upgrading is a function of two opposing contributions: (i) a more aggressive phenotype in smaller prostates and thus increased risk of upgrading; and (ii) more thorough sampling in smaller prostates and thus decreased risk of upgrading. When sampled more thoroughly, the phenotype association dominates and smaller prostates are linked with an increased risk of upgrading. In less thoroughly sampled prostates, these opposing factors nullify, resulting in no association between prostate size and risk of upgrading. These findings help to explain previously published disparate results of the importance of prostate size as a predictor of Gleason upgrading.

Obesity and oncological outcome after radical prostatectomy: impact of prostate-specific antigen-based prostate cancer screening: results from the Shared Equal Access Regional Cancer Hospital and Duke Prostate Center databases

OBJECTIVE

To indirectly test the hypothesis that prostate-specific antigen (PSA)-based screening is biased against obese men due to haemodilution of PSA, and thus results in delayed diagnosis and poorer outcome beyond the biological link between obesity and aggressive prostate cancer.

PATIENTS AND METHODS

We sought to examine the association between body mass index (BMI) and the outcome of radical prostatectomy (RP) separately for men with PSA-detected cancers (cT1c) or with abnormal digital rectal examination (DRE) findings (cT2/T3), and stratified by year of treatment, using two large databases. We conducted a retrospective cohort study of 1375 and 2014 men treated by RP between 1988 and 2007 using the Shared Equal Access Regional Cancer Hospital (SEARCH) and Duke Prostate Center (DPC) databases. We evaluated the association between BMI and adverse pathological features and biochemical progression, using logistic regression and Cox proportional hazards models, adjusting for several clinical characteristics, respectively. Data were examined as a whole and as stratified by clinical stage (cT1c vs cT2/T3) and year of surgery (>or=2000 vs <2000).

RESULTS

In both cohorts a higher BMI was associated with high-grade disease (P <or= 0.02) and positive surgical margins (P < 0.001) and these results did not vary by clinical stage. A higher BMI was significantly associated with biochemical progression (P <or= 0.03) in both cohorts. When stratified by clinical stage, obesity was significantly related to progression in both cohorts among men with T1c cancers (P <or= 0.004) but not in men with cT2/T3 cancers (P > 0.3). Among men with T1c disease, the association between BMI and biochemical progression was limited to men treated in 2000 or later (P <or= 0.002) and was not apparent in men treated before 2000 (P > 0.4).

CONCLUSIONS

Obese men with PSA-detected cancers and treated with RP since 2000 were at significantly greater risk of biochemical progression, while obese men treated before 2000 or diagnosed with an abnormal DRE were not at significantly greater risk of progression. These findings support the hypothesis that current PSA-based screening is less effective at finding cancers in obese men, leading to more aggressive tumours at diagnosis. Lowering the PSA threshold for biopsy among obese men might help to improve outcomes among this high-risk group.

Obesity and positive surgical margins by anatomic location after radical prostatectomy: results from the Shared Equal Access Regional Cancer Hospital database

OBJECTIVES

To determine if there is predilection for any specific anatomical location of positive surgical margins (PSMs) after radical prostatectomy (RP) for prostate cancer in obese men, as previous studies found that obesity was associated with an increased risk of PSMs.

PATIENTS AND METHODS

We analysed retrospectively 1434 men treated with RP between 1989 and 2007 within the Shared Equal Access Regional Cancer Hospital database. The association between increased body mass index (BMI) and overall and site-specific PSMs was assessed using multivariate logistic regression.

RESULTS

After adjusting for several preoperative clinical and pathological characteristics, a higher BMI was associated with an increased risk of PSMs both overall and at all specific anatomical locations (all P <or= 0.007). For mildly obese men, this risk was very similar across all anatomical sites (44-78% increased risk relative to men of normal weight). When BMI was coded as a continuous variable, the odds ratio for the risk of overall PSMs or at any specific locations was nearly identical at 1.05-1.06. Among men with a BMI of >or=35 kg/m2, there was more variation, with the highest excess risk of PSMs at the bladder neck and apex.

CONCLUSIONS

Obesity was associated with an increased risk of overall PSMs and at all anatomical locations. Although the excess risk of PSMs was similar across all anatomical locations, there was a suggestion of a higher risk of apical margins among the most obese men, which if validated, further supports the importance of the apical dissection in all men and suggests added difficulty in obese patients.

Risk stratification for biochemical recurrence in men with positive surgical margins or extracapsular disease after radical prostatectomy: results from the SEARCH database

PURPOSE

In men with extracapsular disease or positive surgical margins after radical prostatectomy immediate adjuvant therapy decreases the risk of biochemical recurrence at the cost of increased toxicity. We further stratified these men into a low risk group in which watchful waiting after surgery may be preferred and a high risk cohort in which adjuvant therapy may be preferred.

MATERIALS AND METHODS

We performed a retrospective analysis of the records of 902 men treated with radical prostatectomy in the Shared Equal-Access Regional Cancer Hospital (SEARCH) database between 1988 and 2007 with positive surgical margins and/or extracapsular disease without seminal vesicle invasion or lymph node metastasis. The significant independent predictors of biochemical recurrence were determined using a multivariate Cox proportional hazards model. Based on the recurrence risk generated from the multivariate Cox proportional hazards regression model we generated tables to estimate the risk of recurrence-free survival 1, 3 and 5 years after surgery.

RESULTS

At a median of 3 years of followup 346 patients (39%) had biochemical recurrence. On multivariate analysis the significant predictors of biochemical recurrence were age more than 60 years, prostate specific antigen more than 10 ng/ml, Gleason score 4 + 3 and 8-10, 2 or more sites of positive surgical margins and prostate specimen weight 30 gm or less. As determined by the concordance index, the overall predictive accuracy of the model was 0.67, while it was 0.60 for the postoperative Kattan nomogram in this patient population.

CONCLUSIONS

We have developed a simple instrument that, once validated, may aid in the postoperative decision making process for men at intermediate risk for recurrence after prostatectomy.

Limitations of prostate specific antigen doubling time following biochemical recurrence after radical prostatectomy: results from the SEARCH database

PURPOSE

Prostate specific antigen doubling time following biochemical recurrence after radical prostatectomy is a powerful predictor of prostate cancer specific and overall death. To calculate prostate specific antigen doubling time requires multiple prostate specific antigen determinations that are unaltered by secondary therapy and separated by sufficient time. Physicians and patients may be unwilling to wait before starting secondary therapy, especially for high risk recurrences. Hence, those with calculable prostate specific antigen doubling time may represent a select lower risk group relative to all men with biochemical recurrence.

MATERIALS AND METHODS

We compared clinical and pathological features between patients with and without calculable prostate specific antigen doubling time. We assessed time trends in the proportion with calculable prostate specific antigen doubling time in 535 patients with biochemical recurrence after radical prostatectomy at 5 Veterans Affairs medical centers comprising the SEARCH (Shared Equal Access Regional Cancer Hospital) database between 1988 and 2003.

RESULTS

Prostate specific antigen doubling time was not calculable in 187 patients (35%) due to secondary therapy in 155 (83%). With time the proportion of patients with calculable prostate specific antigen doubling time decreased significantly (p <0.001). Adverse pathological features, more rapid time to recurrence, higher body mass index and differing surgical centers were associated with not having a calculable prostate specific antigen doubling time. Of all men with recurrence in the most recent year of analysis the adjusted probability of having a calculable prostate specific antigen doubling time was only 43%, that is 61% in patients with favorable pathological results but only 30% in those with seminal vesicle invasion.

CONCLUSIONS

Those with calculable prostate specific antigen doubling time represented a select, lower risk cohort and the proportion of patients with calculable prostate specific antigen doubling time decreased with time. This highlights the need for alternative markers in men with recurrent prostate cancer because one of our best current markers, prostate specific antigen doubling time, is only available in a limited number of patients.

Small transrectal ultrasound volume predicts clinically significant Gleason score upgrading after radical prostatectomy: results from the SEARCH database

PURPOSE

Needle biopsy Gleason scores are often upgraded after pathological examination of the prostate following radical prostatectomy. It has been suggested that larger prostates would be associated with a greater risk of upgrading since a smaller percentage of the gland is sampled and, thus, the highest grade disease would more likely be missed, assuming an equal number of cores is taken from similar locations. We examined the likelihood of clinically relevant upgrading after radical prostatectomy as a function of transrectal ultrasound volume.

MATERIALS AND METHODS

We examined the association between transrectal ultrasound volume and upgrading (higher Gleason score category in the radical prostatectomy specimen than in the biopsy) in 586 men treated with radical prostatectomy between 1995 and 2006 in the SEARCH database who underwent at least a sextant biopsy using multivariate logistic regression. Transrectal ultrasound volume was categorized as 20 or less (in 71), 21 to 40 (in 334), 41 to 60 (in 123) and greater than 60 cm(3) (in 58). Gleason score was examined as a categorical variable of 2-6, 3 + 4 and 4 + 3 or greater.

RESULTS

Overall 138 cases (24%) were upgraded, 80 (14%) were downgraded, and 368 (62%) had identical biopsy and pathological Gleason sum groups. Larger transrectal ultrasound volume was significantly associated with decreased likelihood of upgrading (p trend <0.001). For transrectal ultrasound volumes greater than 60, 41 to 60, 21 to 40 and 20 cm(3) or less, the estimated multivariate adjusted probability of upgrading was 12.6%, 27.5%, 36.4% and 45.5% for Gleason 2-6 tumors, and 6.1%, 8.5%, 18.9% and 20.9% for Gleason 3 + 4 tumors, respectively.

CONCLUSIONS

Larger transrectal ultrasound volumes were at decreased risk for clinically significant upgrading after radical prostatectomy. This fact should be kept in mind when deciding on treatment decisions for men with apparently low grade prostate cancer on biopsy.

Living renal donor allograft lithiasis: a review of stone related morbidity in donors and recipients

PURPOSE

The use of screening computerized tomography angiography has resulted in the increased detection of incidental nephrolithiasis in potential living renal donor candidates. We reviewed current acceptance guidelines for donors with stone disease as well as data on stone related outcomes in donors with stone disease and recipients who received a kidney with a stone left in situ.

MATERIALS AND METHODS

We performed a medical literature search in English using MEDLINE/PubMed that addressed renal donor allograft lithiasis. We then analyzed the literature with respect to the historical evolution of this concept, current guidelines regarding the acceptance of donors with stones and stone related morbidity in recipients and donors.

RESULTS

The prevalence of asymptomatic solitary nephrolithiasis has increased with the widespread use of screening computerized tomography angiography during renal donor evaluation. Few studies have addressed the risk of stone related morbidity in donors and recipients. Short-term studies have shown little stone related morbidity in patients who donate or receive an allograft with a stone left in situ. Consensus statements from transplant societies around the world offer guidance for determining donor eligibility.

CONCLUSIONS

The available literature on stone related morbidity in donors and recipients is extremely limited. It would appear that the risk of recurrence and subsequent morbidity in renal donors with a solitary kidney is low but not insignificant. Rare stone related adverse events are reported for recipients of an allograft with a stone left in situ. Renal donors and recipients should be educated regarding their unique risk perspectives. Long-term followup is mandatory.

Exploring causes for declining prostate cancer mortality rates in the United States

OBJECTIVES

Prostate cancer mortality rates in the U.S.A. increased in the late 1980s and declined from 1993 until 2003. The purpose of this study is to compare declining prostate cancer mortality rates among states with independent variables that may have an association to explore causes for the decline.

METHODS AND MATERIALS

Annual rates of prostate cancer mortality for men over 50 were obtained from the National Vital Statistic System public use data file for states for individual years from 1993 to 2003. The annual rate of prostate cancer mortality decline for each state was calculated by the Joinpoint Regression Program (Statistical Research and Applications Branch of NCI). Annual rates of prostate cancer decline were cross-correlated to state levels of PSA screening, health insurance coverage, obesity, physical inactivity, diabetes, and high cholesterol for males from 45 to 64.

RESULTS

Declining prostate cancer mortality rates for white males correlated with high cholesterol levels (R = -0.42, P = 0.002) and PSA screening levels (R = -0.28, P = 0.05). Declining prostate cancer mortality rates for black males correlated with health insurance coverage (R = -0.43, P = 0.03).

CONCLUSIONS

Declining prostate cancer mortality rates are weakly associated with increased PSA screening for white males but there was no association for black males, possibly because blacks have less access to medical care. The strong inverse correlation between declining prostate cancer mortality rates and levels of white males with high cholesterol levels was unexpected but may be associated with the widespread use of cholesterol reducing medications (statins), which are hypothesized to reduce prostate cancer risk.

Obesity-related plasma hemodilution and PSA concentration among men with prostate cancer

CONTEXT

Recent studies have suggested that obese men have lower serum prostate-specific antigen (PSA) concentrations than nonobese men. Because men with higher body mass index (BMI) have greater circulating plasma volumes, lower PSA concentrations among obese men may be due to hemodilution.

OBJECTIVE

To determine the association between hemodilution and PSA concentration in obese men with prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective study of men who underwent radical prostatectomy for prostate adenocarcinoma from 1988 to 2006, using data from the databases of the Shared Equal Access Regional Cancer Hospital (n = 1373), Duke Prostate Center (n = 1974), and Johns Hopkins Hospital (n = 10 287). Multivariate linear regression models adjusting for clinicopathological characteristics were used to analyze the main outcome measures.

MAIN OUTCOME MEASURES

Associations between BMI and mean adjusted PSA concentrations, mean plasma volume, and mean adjusted PSA mass (total circulating PSA protein, calculated as PSA concentration multiplied by plasma volume), assessed by determining P values for trend.

RESULTS

After controlling for clinicopathological characteristics, higher BMI was significantly associated with higher plasma volume (P < .001 for trend) and lower PSA concentrations (P < or = .02 for trend) in all cohorts. In 2 of the 3 cohorts, PSA mass did not change significantly with increasing BMI. In the third cohort, higher BMI was associated with increased PSA mass (P < .001 for trend), but only between BMI category less than 25 and the other categories.

CONCLUSIONS

In men undergoing radical prostatectomy, higher BMI was associated with higher plasma volume; hemodilution may therefore be responsible for the lower serum PSA concentrations among obese men with prostate cancer. Prospective studies are needed to evaluate this association in screened populations.

Risk stratification of men with Gleason score 7 to 10 tumors by primary and secondary Gleason score: results from the SEARCH database

OBJECTIVES

Gleason score 4+3 prostate cancer is associated with worse clinicopathologic outcomes than is Gleason score 3+4. Whether the increased risk associated with Gleason score 4+3 disease is equivalent to that of Gleason score 4+4 or greater is unclear.

METHODS

We reviewed the data from two separate cohorts pulled from the Shared Equal Access Regional Cancer Hospital database. The first consisted of 374 men with biopsy Gleason score 3+4 or greater disease and the second of 636 men with radical prostatectomy (RP) Gleason score 3+4 or greater disease. We estimated the odds ratios of unfavorable surgical pathologic findings for the biopsy Gleason score categories using logistic regression analysis. Using a Cox proportional hazards regression model, we estimated the relative risk of biochemical progression associated with each biopsy and RP Gleason score category.

RESULTS

In the biopsy Gleason score cohort, a Gleason score of 4+3 was associated with an increased risk of extracapsular extension (P = 0.01) and seminal vesicle invasion (P <0.001) relative to a biopsy Gleason score of 3+4. A biopsy Gleason score of 4+3 was associated with a similar risk of adverse pathologic findings relative to a biopsy Gleason score of 4+4 or greater (all P >0.10), except for higher grade pathologic tumors among men with a biopsy Gleason score of 4+4 or more (P = 0.001). After adjusting for multiple clinical characteristics, a biopsy Gleason score of 4+3 was associated with an increased recurrence risk relative to a biopsy Gleason score of 3+4 (P = 0.001), but a similar progression risk as that for a biopsy Gleason score of 4+4 or more (P = 0.53). In the RP Gleason cohort, and after adjustment for multiple clinicopathologic features, an RP Gleason score of 4+3 was associated with increased progression risk relative to an RP Gleason score of 3+4 (P = 0.03), but similar progression risk as that for an RP Gleason score of 4+4 or more (P = 0.24).

CONCLUSIONS

In a multicenter database using pooled data from multiple pathologists, Gleason scores 4+3 and 4+4 or more exhibited similar clinicopathologic outcomes.

Body Mass Index, Prostate Weight and Transrectal Ultrasound Prostate Volume Accuracy

PURPOSE

Transrectal ultrasound can be used to calculate prostate volume, which has implications for benign and malignant prostate disease. We hypothesized that obesity may represent a technical challenge when performing transrectal ultrasound that decreases the accuracy of estimating prostate volume.

MATERIALS AND METHODS

We examined the records of men with previously untreated prostate cancer who underwent radical prostatectomy between 1995 and 2006 and who were in the Shared-Equal Access Regional Cancer Hospital database. Transrectal ultrasound volume calculations were correlated with radical prostatectomy specimen weight using the Spearman coefficient. We calculated the percent and absolute error, and evaluated the relationship between them and transrectal ultrasound volume, body mass index, age, prostate specific antigen and race using multivariate linear regression.

RESULTS

A total of 497 patients with preoperative transrectal ultrasound volume, specimen weight and body mass index data were identified in the Shared-Equal Access Regional Cancer Hospital database. Transrectal ultrasound volume correlated modestly with specimen weights (r = 0.692, p <0.001). The median +/- SD absolute error was 9.6 +/- 11.4 gm and the median +/- SD percent error was 22.9% +/- 20.6%. Body mass index was not significantly related to absolute or percent error (p = 0.91 and 0.71, respectively). In addition, patient age, prostate specific antigen and race were not significantly related to absolute or percent error (p >0.05). However, percent error but not absolute error was significantly predicted by transrectal ultrasound volume (p <0.001 and 0.34, respectively). Smaller prostate size was associated with greater percent error, especially when transrectal ultrasound volume was less than 20 cc.

CONCLUSIONS

Transrectal ultrasound volume correlates with specimen weight but it is an imperfect substitute with significant variation in error. The accuracy of transrectal ultrasound depends on measured volume but neither body mass index nor other patient specific variables had a significant impact.

Do racial differences in prostate size explain higher serum prostate-specific antigen concentrations among black men?

OBJECTIVES

To determine whether elevated serum prostate-specific antigen (PSA) values in black men are due, at least partially, to larger prostate size among black men.

METHODS

The study population consisted of two cohorts: (1) 1410 men undergoing radical prostatectomy between 1988 and 2005 at five equal-access medical centers comprising the Shared Equal Access Regional Cancer Hospital (SEARCH) Database; and (2) 9601 men undergoing radical prostatectomy between 1988 and 2004 at the Johns Hopkins Hospital. We evaluated the association between race and serum PSA value and prostate weight using multivariable linear regression while adjusting for demographic and clinicopathologic cancer characteristics.

RESULTS

In both cohorts, black men had higher serum PSA values (P < or = 0.001). After adjusting for either demographic characteristics or demographic and cancer-specific characteristics, there were no significant associations between race and prostate size in either cohort. After adjusting for multiple demographic, clinical, and pathologic cancer-specific characteristics, black men had 15% higher serum PSA values relative to white men in both the SEARCH (P = 0.001) and Hopkins cohorts (P < 0.001).

CONCLUSIONS

In this study of patients undergoing radical prostatectomy in two very different practice settings, black men in both cohorts had higher serum PSA values relative to white men, despite adjustment for demographic and cancer-specific characteristics, including prostate weight. The lack of significant association between race and prostate size suggests that alternative reasons are needed to explain higher serum PSA values in black men.

Predicting unilateral prostate cancer based on biopsy features: implications for focal ablative therapy--results from the SEARCH database

PURPOSE

For men with low risk prostate cancer it was recently proposed that ablative treatment to the affected side may decrease morbidity, while maintaining good oncological outcomes. However, few studies have assessed the correlation between biopsy parameters and pathological outcome (unilateral vs bilateral disease).

MATERIALS AND METHODS

Using the Shared Equal Access Regional Cancer Hospital Database of men treated with radical prostatectomy at multiple equal access medical centers we retrospectively examined the records of 261 men with clinical stage T1c or T2a prostate cancer, prostate specific antigen less than 10 ng/ml, Gleason sum 6 or less and only 1 or 2 ipsilateral positive cores on at least sextant biopsy. We compared clinical characteristics between men with pathologically unilateral disease or less (pT2b or less) and men with pathologically bilateral disease or extraprostatic extension (pT2c or greater). To determine the significant predictors of pT2c or greater disease we used a multivariate logistic regression model.

RESULTS

Of the cohort of 261 men with low risk prostate cancer only 93 (35.1%) had unilateral or no evidence of disease following examination of radical prostatectomy specimens. Men with pathologically unilateral or less disease did not differ from those with bilateral or more advanced disease by age, prostate specific antigen, clinical stage, body mass index or number of positive biopsy cores (1 vs 2). On multivariate analysis no clinical feature was significantly related to pathologically unilateral or less vs bilateral or greater disease.

CONCLUSIONS

The majority of men with low risk prostate cancer and 1 or 2 ipsilateral positive biopsy cores have pathologically bilateral disease. Therefore, strategies for unilateral treatment of prostate cancer are unlikely to be curative for these men.

Computerized tomographic angiography for renal donor evaluation leads to a higher exclusion rate

PURPOSE

We compared the exclusion rate for potential living renal donors evaluated with computerized tomography angiography and radionuclide renal scintigraphy (renal scan) vs excretory urogram, renal scan and renal arteriography.

MATERIALS AND METHODS

From March 2004 through February 2006, 603 consecutive patients were evaluated as potential living renal donors. From March 2004 through February 2005, 270 consecutive patients underwent evaluation with excretory urogram, renal scan and renal angiography (group 1). Of these patients 16 underwent computerized tomography to evaluate abnormalities detected on excretory urogram. From March 2005 through February 2006, 333 consecutive patients underwent evaluation with computerized tomography angiography and renal scan (group 2). The number of patients excluded for medical reasons and/or radiographic abnormalities was determined for the 2 groups.

RESULTS

More than twice as many patients evaluated with computerized tomography were excluded. In group 1, 7% of patients (20 of 270) were excluded from donation due to radiographic findings vs 16% (53 of 333) in group 2 (p=0.0016). Of the patients 26% and 23% were excluded from renal donation for medical reasons in groups 1 and 2, respectively (p=0.5059).

CONCLUSIONS

Multidetector row computerized tomography angiography increases the detection of incidental radiographic abnormalities as well as the renal donor exclusion rate. The increased sensitivity of computerized tomography angiography has created a dilemma for those determining patient eligibility for kidney donation because the clinical significance of many of these findings is unclear. Additional studies should address the significance of these incidental findings so that patients are not needlessly excluded from kidney donation.

Impact of Obesity on the Utility of Preoperative Prostate-Specific Antigen Velocity to Predict for Relapse After Prostatectomy: A Report from the SEARCH Database

OBJECTIVES

To test the validity of preoperative prostate-specific antigen velocity (PSAV) (the rate of PSA rise before diagnosis) as a predictor for relapse after radical prostatectomy, in the context of patient obesity as measured by body mass index (BMI).

METHODS

The rates of biochemical relapse were examined among 215 patients who underwent radical prostatectomy between 1992 and 2005. Kaplan-Meier relapse rates as a function of preoperative PSAV 2 ng/mL/yr or less versus greater than 2 ng/mL/yr were compared in two groups: nonobese patients (normal to overweight, BMI less than 30 kg/m2) and obese patients (mild to severely obese, BMI 30 kg/m2 or greater).

RESULTS

A preoperative PSAV greater than 2 ng/mL/yr was associated with higher relapse rates after radical prostatectomy compared with a PSAV of 2 ng/mL/yr or less, with 5-year relapse-free survival rates of 60% versus 70%, respectively (P = 0.03). Prostate-specific antigen velocity was independently significant on multivariate analysis, along with biopsy Gleason score, percent positive cores, and BMI. In this study 24% of patients were obese. Prostate-specific antigen velocity greater than 2 ng/mL/yr was associated with higher relapse rates in nonobese patients (P = 0.01) but not in obese patients (P = 0.9). The two BMI groups did not differ with respect to any factors. Obese patients with slowly rising PSA (PSAV 2 ng/mL/yr or less) fared just as poorly as nonobese patients with rapidly rising PSA (PSAV greater than 2 ng/mL/yr). Obesity was independently associated with higher relapse rates.

CONCLUSIONS

Preoperative PSAV greater than 2 ng/mL/yr was associated with a higher risk of relapse after radical prostatectomy, but its clinical usefulness might be limited to nonobese patients. Obesity conferred higher relapse rates, regardless of other prognostic factors including preoperative PSAV.

Upgrading and downgrading of prostate needle biopsy specimens: risk factors and clinical implications

OBJECTIVES

The prostate biopsy Gleason grade frequently differs from the radical prostatectomy (RP) grade. Given the critical role that needle biopsy plays in treatment decisions, we sought to determine the risk factors for upgrading and downgrading the prostate biopsy specimen.

METHODS

We determined the significant predictors of upgrading (worse RP grade than biopsy grade) and downgrading (better RP grade than biopsy grade) among 1113 men treated with RP from 1996 to 2005 within the Shared Equal Access Regional Cancer Hospital (SEARCH) database who had undergone at least sextant biopsy. The Gleason sum was examined as a categorical variable of 2 to 6, 3+4, and 4+3 or greater.

RESULTS

Overall, the disease of 299 men (27%) was upgraded and 123 (11%) was downgraded, and 691 men (62%) had identical biopsy and pathologic Gleason sum groups. Upgrading was associated with adverse pathologic features (P < or = 0.001) and the risk of biochemical progression (P = 0.001). Downgrading was associated with more favorable pathologic features (P < or = 0.01) and a decreased risk of progression (P = 0.04). On multivariate analysis, greater prostate-specific antigen levels (P < 0.001), more biopsy cores with cancer (P = 0.001), and obesity (P = 0.003) were all significantly and positively associated with upgrading. In contrast, biopsy Gleason sum 3+4 (P = 0.001) and obtaining eight or more biopsy cores (P = 0.01) were associated with a lower likelihood of upgrading.

CONCLUSIONS

Men whose disease was upgraded were at a greater risk of adverse pathologic features and biochemical progression. Men with "high-risk" cancer (greater prostate-specific antigen levels, more positive cores, and obese) were more likely to have their disease category upgraded, and obtaining more biopsy cores reduced the likelihood of upgrading.

Optimal Timing, Cutoff, and Method of Calculation of Preoperative Prostate-Specific Antigen Velocity to Predict Relapse After Prostatectomy: A Report from SEARCH

OBJECTIVES

Preoperative prostate-specific antigen (PSA) velocity (PSAV), the rate of PSA rise preceding diagnosis, predicts for relapse and cancer death after prostatectomy or radiotherapy. We studied the timing, cutoff levels, and method of calculation to better define its usefulness.

METHODS

The rates of biochemical relapse were examined in 471 patients who underwent radical prostatectomy (RP) with previous PSA history available. PSAV was calculated by two methods, as the difference between two PSAs divided by time, or as the slope of all available PSAs within that interval. Kaplan-Meier relapse-free survival was compared among the groups with various intervals and cutoff levels in their preoperative PSAV definition. Univariate and multivariate analysis examined all preoperative factors and PSAV for their association with relapse.

RESULTS

The two methods of PSAV calculation yielded values within 5% of each other (R2 = 0.91). A PSA history that precedes RP by at least 12 months is necessary. A PSAV cutoff level of 2 ng/mL/yr or less versus greater than 2 ng/mL/yr appeared optimal for a PSA interval spanning 12 to 24 months before RP (P = 0.008). PSAV using a longer interval (24 to 36 months) before RP appeared more sensitive, with a cutoff of 1 ng/mL/yr or less versus greater than 1 ng/mL/yr (P = 0.029) and 2 ng/mL/yr or less versus greater than 2 ng/mL/yr (P = 0.0041) associated with relapse. A preoperative PSAV of 2 ng/mL/yr or less versus greater than 2 ng/mL/yr was an independent factor associated with the risk of relapse after RP.

CONCLUSIONS

The results of our study have shown that preoperative PSAV is independently associated with relapse after RP. However, a minimum interval of 12 months before RP is needed, and a PSAV cutoff level of 2 ng/mL/yr appears optimal. A simple two-point method of calculating PSAV is reliable.