Hepatic Resection: The Last Surgical Frontier for Colorectal Cancer

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.

Prostate weight and early potency in robot-assisted radical prostatectomy

OBJECTIVES

Using an athermal technique for nerve preservation we noted that approximately 40% are potent compared with approximately 60% who are not at 3 months after robot-assisted laparoscopic prostatectomy (RLP). In an attempt to understand this difference, we examine factors potentially influencing potency at 3 months.

METHODS

Of 300 consecutive RLPs, we identified 139 men who met preoperative inclusion criteria: age <or= 65 years with International Index of Erectile Function (IIEF-5) scores of 22-25. All men were instructed to take 5'-phosphodiesterase inhibitors postoperatively. All data were collected and entered prospectively into an electronic database. Sexual outcomes were obtained via self-administered validated questionnaires. We defined potency by affirmative answers to the following questions: Were erections adequate for penetration, and were they satisfactory?

RESULTS

At 3 months, 53 subjects (38%) were potent. Univariate and multivariate analysis demonstrated no effect for IIEF-5 score, body mass index, nerves spared, estimated blood loss, hypertension, diabetes, use of cholesterol-lowering agents, and lifestyle issues. Prostate weight (43.3 vs 51.4 g, P = .038) and age (55 vs 57, P = .03) were significant in univariate analysis. In multivariate analysis only prostate weight was predictive of potency (P = .04). To ascertain a possible relation between traction nerve injury and prostate weight, analysis between prostate weight groups and potency demonstrated an inverse relationship.

CONCLUSIONS

Low prostate weight was the only factor found to correlate with early return of potency. Our data also suggest that increasing prostate weight increases the risk of delay in potency recovery.

The impact of prostate gland weight in robot assisted laparoscopic radical prostatectomy

PURPOSE

We determined whether prostate weight has an impact on the pathological and operative outcomes of robot assisted laparoscopic radical prostatectomy.

MATERIALS AND METHODS

We reviewed the records of 1,847 consecutive patients who underwent robot assisted laparoscopic radical prostatectomy at our institution. Variables were compared across quartile distributions of prostate size as defined by weight, including group 1-less than 30 gm, group 2-30 to 49.9, group 3-50 to 69.9 and group 4-70 or greater. Factors assessed in this analysis were patient age, body mass index, prostate specific antigen, Gleason score, pathological stage, margin status, operative time, blood loss, transfusion rate, length of stay and rehospitalization rate.

RESULTS

Patients with a larger prostate (group 4) were older (mean age 66.2 years), had higher pretreatment prostate specific antigen (median 6.5 ng/ml), lower Gleason score (mean 6.3), longer operative time (mean 3.2 hours), higher estimated blood loss (median 250 cc) and longer hospital stay (p = 0.0002). There was a trend toward higher risk disease based on D'Amico risk stratification and positive margin status in group 1, although evidence of extracapsular extension was more common in groups 2 and 3. There was no association between prostate size and body mass index, lymph node status, blood transfusion rate, seminal vesicle involvement and rehospitalization rate.

CONCLUSIONS

Robot assisted laparoscopic radical prostatectomy in patients with an enlarged prostate is feasible with slightly longer operative time, urinary leakage rates and hospital stay. Pathologically larger prostates are generally associated with lower Gleason score and risk group stratification. One-year continence rates and biochemical recurrence rates are similar across all groups.

The role of testosterone in the pathogenesis of prostate cancer

Relationships between androgenic hormones and prostatic tissue growth are complex. It is certainly true that the prostate will not develop without androgens and the gland will atrophy if androgen support is withdrawn. The hormonal hypothesis remains one of the most important hypotheses in the etiology of prostate cancer (PCa), and efforts are continuing to improve the understanding of androgen actions in PCa. Although evidence from epidemiological studies of associations between circulating levels of androgens and PCa risk has been inconsistent, the traditional view that higher testosterone (T) levels represent a risk factor for PCa appears to have little evidentiary support. Reinvestigation of the relationship between T and PCa seems important and necessary if a new, clinically and scientifically rewarding concept is to be constructed. The present review considers the metabolism and intraprostatic action of T, epidemiological evidence, and the association between T and PCa risk.

Intra-prostatic androgen levels during various androgen-blockade regimens

Androgens are heavily involved in the development of prostate cancer. This article reviews the scenario of the androgen environment and androgen metabolism in the prostate during androgen-deprivation therapy (ADT) in patients with prostate cancer. Ways of altering the intra-prostatic androgen milieu during various androgen-blockade regimens include surgical castration, luteinizing hormone-releasing hormone analogues to block androgen secretion by the testes, anti-androgens, and 5alpha-reductase inhibitors. The levels of androgen precursors in the blood are different under different ADT regimens, and the androgen levels in the prostate also vary according to the ADT used. This may affect the therapeutic effect of ADT. We therefore discuss the subject of prostatic androgen levels during various androgen-blockade regimens, and we describe the prospects for the future of ADT.

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.

Impact of socioeconomic factors on prostate cancer outcomes in black patients treated with surgery

OBJECTIVES

The role of socioeconomic factors in the worse outcome of black men with prostate cancer remains unclear. To determine whether socioeconomic factors affect prostate cancer outcomes, we studied a cohort of only black patients to minimize known confounding factors.

METHODS

We studied black men treated with radical prostatectomy at New York Veterans Administration Medical Center and Memorial Sloan-Kettering Cancer Center between 1990 and 2005. A centralized pathology review process determined the Gleason score of all cases. Prostate-specific antigen (PSA) recurrence at both sites was defined as PSA of 0.2 or greater with a confirmatory rise. By matching patients' home zip codes to the U.S. Census Bureau database, we obtained corresponding socioeconomic data regarding median household income (income) and percentage of population with a high school (degree). We analyzed income, education, and clinical and pathological parameters for the whole cohort.

RESULTS

We studied 430 black patients. They resided in neighborhoods where median household income was $41,498.10 and mean percentage of high school graduates was 73.4%. A total of 88 patients (20.9%) had PSA recurrence. Median follow-up for survivors was 37 months. Neither income nor education evaluated as continuous or categorical variables were predictors of PSA recurrence. When evaluated as composite categorical variable, the combination of greater income and education did not predict disease-free survival.

CONCLUSIONS

Data suggest that socioeconomic factors have limited impact on PSA recurrence in black men treated with radical prostatectomy. Thus, biologic factors might have a role in the poor outcomes in this population.

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.

Prostate cancer volume at biopsy predicts clinically significant upgrading

PURPOSE

A significant proportion of patients with prostate cancer with Gleason score 6 disease at biopsy is upgraded to Gleason score 7 or higher after radical prostatectomy, increasing the risk of adverse outcome. We identified clinical and pathological parameters that predict pathological upgrading in this population.

MATERIALS AND METHODS

A total of 268 patients with biopsy Gleason score 6 prostate cancer who underwent biopsy and radical prostatectomy between October 1999 and January 2007 were included in the study. Pretreatment characteristics were used to identify predictors of pathological upgrading. Upgrading significance was established by comparing radical prostatectomy pathology between cases that were and were not upgraded.

RESULTS

A total of 134 patients (50%) were upgraded postoperatively to Gleason score 7 or higher. Preoperative prostate specific antigen greater than 5.0 ng/ml (p = 0.036), prostate weight 60 gm or less (p = 0.004) and more cancer volume at biopsy, defined by cancer involving greater than 5% of the biopsy tissue (p = 0.002), greater than 1 biopsy core (p <0.001) or greater than 10% of any core (p = 0.014), were associated with pathological upgrading. Upgraded patients were more likely to have extraprostatic extension and positive surgical margins at radical prostatectomy (p <0.001 and 0.001, respectively).

CONCLUSIONS

Prostate specific antigen, prostate volume and biopsy cancer volume predict clinically significant upgrading in patients diagnosed with Gleason score 6 disease. These parameters may be valuable in the pretreatment risk assessment of this patient population.

High yield of saturation prostate biopsy for patients with previous negative biopsies and small prostates

OBJECTIVES

Men with previously negative prostate biopsies but continued suspicion for carcinoma present a diagnostic dilemma often managed by saturation prostate biopsy (SPB). We sought to determine the patient characteristics for which repeat biopsy by SPB provides the greatest utility for prostate cancer detection.

METHODS

The records of the men at the state hospital and affiliated Veterans Affairs Medical Center with previously negative prostate biopsy findings who had then undergone SPB were reviewed. The predictors of cancer were analyzed, and those that were significant were included in a multivariate logistic regression model.

RESULTS

A total of 82 men underwent SPB from November 2001 to March 2006. Their mean age was 61 years (range 43 to 76), and 44 (54%) were white, 37 (45%) were African American, and 1 (1%) was Asian. The mean prostate-specific antigen level at SPB was 9.1 ng/mL (range 1.0 to 34). The number of prior biopsies was one in 43 patients (52%) and two or more in 39 patients (47%). The prostate volume averaged 53 cm(3) (range 12 to 200). SPB included a median of 24 cores (range 24 to 40). Of the 82 patients, 16 (19.5%) were diagnosed with cancer, of whom 10 (63%) elected to undergo radical prostatectomy. The only significant predictors of prostate cancer were the prostate-specific antigen level (P = 0.009) and prostate volume. The cancer detection rate was 57% for patients with a prostate volume less than 37 cm(3) and 7% for those with larger glands, and the difference was significant on multivariate analysis (odds ratio 31, 95% confidence interval 6 to 158, P <0.0001).

CONCLUSIONS

The results of our study have shown that SPB is an effective diagnostic tool with a high yield for men with persistent suspicion for prostate cancer, prior negative biopsy findings, and a prostate volume less than 37 cm(3).

Contemporary prostate cancer prevalence among T1c biopsy-referred men with a prostate-specific antigen level < or = 4.0 ng per milliliter

OBJECTIVE

To investigate the prostate cancer (PCa) prevalence and risk factors of men with prostate-specific antigen (PSA) level< or =4.0 ng/ml and an unsuspicious digital rectal examination (DRE) in a large biopsy referral cohort.

MATERIALS AND METHODS

Between 1997 and 2005, 855 men underwent initial transrectal ultrasound (TRUS)-guided prostate biopsy at the University Hospital Hamburg-Eppendorf. Patients with any previous surgical or medical treatment were excluded from analyses. Logistic regression analyses were performed to determine risk factors of PCa at biopsy and high-grade PCa defined as biopsy Gleason sum> or =7.

RESULTS

Overall PCa detection rate was 23.1%. The majority had a biopsy Gleason sum of 6 (79.5%) and 20.5% had a biopsy Gleason sum> or =7. Total PSA (tPSA) and percentage of free PSA (%fPSA) were statistically significantly different in men with and without PCa (all p<0.001). In tPSA strata < or = 0.5, 0.6-1.0, 1.1-2.0, 2.1-3.0, and 3.1-4.0 ng/ml, PCa prevalence was 4.0%, 10.6%, 14.8%, 24.5%, and 32.1%, respectively. In logistic regression analyses addressing PCa and Gleason sum > or = 7 at biopsy, %fPSA and prostate volume represented independent and most informative risk factors.

CONCLUSION

Our data demonstrate that a substantial percentage (23.1%) of men with a PSA< or =4.0 ng/ml and an unsuspicious DRE in a biopsy referral population harbor PCa, with 20.5% being high grade. Low %fPSA and low prostate volume represent important parameters in PCa and in high grade disease detection at biopsy, respectively.

Obesity does not predispose to more aggressive prostate cancer either at biopsy or radical prostatectomy in European men

Many investigators suggested that obesity predisposes to adverse prostate cancer characteristics and outcomes. We tested the effect of obesity on the rate of aggressive prostate cancer at either prostate biopsy or radical prostatectomy (RP). Clinical and pathological data were available for 1,814 men. Univariable and multivariable logistic regression models addressed the rate of high grade prostate cancer (HGPCa) at either biopsy or final pathology. Clinical stage, prostate-specific antigen (PSA), percentage of free PSA and prostate volume were the base predictors. All models were fitted with and without body mass index (BMI), which quantified obesity. BMI and its reciprocal (InvBMI) were coded as cubic splines to allow nonlinear effects. Predictive accuracy (PA) was quantified with area under curve estimates, which were subjected to 200 bootstrap re-samples to reduce overfit bias. Gains in PA related to the inclusion of BMI were compared using the Mantel-Haenszel test. HGPCa at biopsy was detected in 562 (31%) and HGPCa at RP pathology was present in 931 (51.3%) men. In either univariable or multivariable models predicting HGPCa at biopsy, BMI or InvBMI failed to respectively reach statistical significance or add to multivariable PA (BMI gain = 0%, p = 1.0; InvBMI gain = -0.2%, p = 0.9). Conversely, in models predicting HGPCa at RP, BMI and InvBMI represented independent predictors but failed to increase PA (BMI gain = 0.7%, p = 0.6; InvBMI gain = 0.5, p = 0.7%). Obesity does not predispose to more aggressive prostate cancer at biopsy. Similarly, obesity does not change the ability to identify those who may harbor HGPCa at RP.

Preoperative Serum Testosterone Level as an Independent Predictor of Treatment Failure following Radical Prostatectomy

OBJECTIVES

Preoperative low serum testosterone (TS) level has been reported to be associated with adverse pathologic results in patients with clinically localized prostate cancer (pCA) treated with radical prostatectomy (RP). However, prior studies failed to show prognostic impact of preoperative low TS in these patients. The aim of this study was to investigate the relationship between preoperative TS and prostate-specific antigen (PSA) failure in these patients.

METHODS

Of 304 patients diagnosed with clinically localized pCA who had been treated with RP alone, 272 patients whose preoperative TS level had been measured were eligible for this analysis. Postoperative TS levels were also available in 222 of the 272 patients. Cox proportional hazard model was used to elucidate factors predictive for PSA failure.

RESULTS

Of the 272 patients 49 had low (< 300 ng/dl) and 223 had normal preoperative TS level. In a stepwise multivariate analysis, preoperative TS (p = 0.021) was an independent and significant predictor of PSA failure along with RP Gleason score (p = 0.006), surgical margin status (p = 0.0001), and PSA (p = 0.0001). Five-year PSA failure-free survival rate of the patients with preoperative low TS (67.8%) was significantly worse than that with normal TS (84.9%) (p=0.035). Serum TS levels increased significantly after RP (p < 0.0001). The increment of TS level in preoperative low TS group was significantly greater than that in preoperative normal TS group (p = 0.0003).

CONCLUSIONS

The current results demonstrated that preoperative TS level is an independent and significant predictor of PSA failure after RP in patients with clinically localized pCA.

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.

Effect of Prostate Volume on Tumor Grade in Patients Undergoing Radical Prostatectomy in the Era of Extended Prostatic Biopsies

PURPOSE

We investigated the influence of prostate volume on biopsy and prostatectomy Gleason score, the incidence of upgrading and total tumor volume.

MATERIALS AND METHODS

From 1997 to 2004, 247 patients were diagnosed with prostate cancer by multisite extended prostatic biopsy (10 or 11 cores) and underwent radical prostatectomy at our institution without neoadjuvant therapy. Medical records were reviewed to determine patient age at diagnosis, preoperative prostate specific antigen, prostate volume, clinical stage, biopsy Gleason score, pathological stage, prostatectomy Gleason score and total tumor volume. The Mann-Whitney and chi-square tests were used to compare variables among groups and multivariate regression analysis was used to determine predictors of Gleason score.

RESULTS

Median patient age was 61 years and median preoperative prostate specific antigen was 5.5 ng/ml. Median prostate volume on transrectal ultrasound was 37 cc. Prostatectomy Gleason score was 6 in 31% of cases, 7 in 57% and 8-9 in 12%. Prostate volume greater than 50 cc was significantly associated with a higher incidence of well differentiated tumors (Gleason score 6) at prostatectomy, that is 17.9% in patients with a prostate volume of 25 cc or less, 28.9% in those with a prostate volume of 25 to 50 cc and 45.3% in those with a prostate volume of greater than 50 cc (p<0.01). In addition, the incidence of tumor upgrading was significantly lower in patients with a large prostate volume (greater than 50 cc) compared to that in those with a smaller prostate volume (20.8% vs 36.1%, p<0.05), particularly in the subset with biopsy Gleason score 6 (24% vs 54.1%, p<0.01). Patients with a large prostate volume (greater than 50 cc) had smaller total tumor volume with a trend toward statistical significance (median total tumor volume 0.86 vs 1.1 cc, p=0.0631).

CONCLUSIONS

In the era of extended prostatic biopsies patients with a large prostate volume have a significantly higher incidence of well differentiated tumor at prostatectomy and a lower likelihood of tumor upgrading.

Association of Prostate Size and Tumor Grade in Korean Men with Clinically Localized Prostate Cancer

OBJECTIVES

To investigate the association of prostate size with aggressiveness of prostate cancer in Korean men who received radical retropubic prostatectomy (RRP) for clinically localized prostate cancer.

METHODS

We evaluated the association of RRP specimen weight and prostate volume measured by transrectal ultrasound (TRUS) with pathologic tumor grade, extraprostatic extension of disease, surgical margin status, and seminal vesicle invasion by reviewing data of 346 consecutive patients who underwent RRP for clinically localized prostate cancer at our institution without receiving preoperative radiation or hormonal treatment.

RESULTS

A strong correlation was observed between RRP specimen weight and TRUS-measured prostate volume (Spearman r = 0.76; P <0.001). After adjustment for multiple variables including age, body mass index, and preoperative prostate-specific antigen level, RRP specimen weight was observed to be significantly associated with presence of Gleason pattern 4 or greater at RRP in an inverse fashion (P = 0.03). Regarding other adverse pathologic features, prostate weight was also significantly inversely associated with extraprostatic extension of prostate cancer (P = 0.04) and surgical margin positivity (P = 0.002). When TRUS-measured prostate volume was applied in place of RRP specimen weight, results were the same.

CONCLUSIONS

Our data indicate that prostate size may be a useful predictor of tumor aggressiveness in Korean men with clinically localized prostate cancer. Further efforts should be made to elucidate actual mechanisms behind the association of prostate size and/or in vivo androgenicity with aggressiveness of prostate cancer.

[The low weight of the prostate is an independent risk factor for positive surgical margins on radical prostatectomy specimens]

OBJECTIVE

The presence of positive surgical margins (PSM) on radical prostatectomy specimen is predictive of biological recurrence. Our objective was to analyze the influence of prostate weight on surgical margins status after radical prostatectomy.

PATIENTS AND METHODS

A cohort of 295 patients operated consecutively between 1998 and 2004 at our institution was prospectively studied. The variables significantly associated with the surgical margins status in univariate analysis were used for multivariate analysis.

RESULTS

The overall rate of PSM was 23% (9% for pT2 patients). Parameters significantly associated with surgical margins status were preoperative PSA (p = 0.02), number of positive biopsy cores (p = 0.04), pathological stage (p < 0. 001), and Gleason score on radical prostatectomy specimen (p < 0. 001). In addition, patient age and surgical specimen weight were conversely associated with surgical margins status (p = 0.008 and p = 0.001, respectively). In multivariate analysis, only three parameters were found to be independent factors of PSM: the pathological stage (p < 0. 001), the patient age (p = 0. 02), and the surgical specimen weight (p = 0.02). PSM rates were 6% and 25% in patients with prostate > 70g and < 70g, respectively (p = 0.008), and 15% and 28% in those with prostate weight > or = 50g and < 50g, respectively (p = 0.015).

CONCLUSION

Low prostate weight is an independent risk factor of PSM. Patients with prostate weight > or = 70g should be considered at low risk of PSM, while those with prostate weight < 50g are at high risk of PSM.

Determining optimal clinical target volume margins on the basis of microscopic extracapsular extension of metastatic nodes in patients with non-small-cell lung cancer

PURPOSE

To determine the optimal clinical target volume (CTV) margins around the nodal gross tumor volume (GTV) in non-small-cell lung cancer (NSCLC) patients by assessing microscopic tumor extension beyond regional lymph node capsules.

METHODS AND MATERIALS

The incidence of nodal extracapsular extension (ECE) and relationship with nodal size were reviewed in 243 patients. Histologic sections of dissected regional lymph nodes up to 30 mm in size were examined to measure the extent of microscopic ECE. We determined the distribution of cases according to extent of ECE and the relationships between ECE extent and lymph node size, regional nodal disease extent, histologic type, and degree of differentiation.

RESULTS

The nodal ECE was seen in 41.6% of patients (101/243) and 33.4% of lymph nodes (214/640), and the incidence correlated to larger lymph node size positively. The extent of ECE was 0.7 mm in mean (range, 0-12.0 mm) and <or=3 mm in 95% of the nodes. Positive correlations were found between extent of ECE and larger lymph node size (>or=20 mm vs. 10-19 mm or <10 mm, p = 0.005), advanced nodal stage (N2 vs. N1, p = 0.046), and moderate or poor (vs. good or unknown) nodal differentiation (p = 0.002). ECE did not differ significantly by histologic type or nodal station.

CONCLUSIONS

The incidence of ECE related to lymph node size, and ECE extent related to lymph node size, stage, and differentiation. It may be reasonable to recommend 3-mm CTV margins for pathologic lymph nodes <20 mm and more generous margins for lymph nodes >or=20 mm.

Effect of Prostate Weight on Operative and Postoperative Outcomes of Robotic-Assisted Laparoscopic Prostatectomy

OBJECTIVES

To determine the effect of prostate weight (PW) on robotic laparoscopic radical prostatectomy (RLRP) outcomes. The effect of PW on surgical and pathologic outcomes has been reviewed in open and laparoscopic prostatectomy series. Little is known about its effects during RLRP.

METHODS

From February 2003 to November 2005, 375 men underwent RLRP. Patients were divided into four groups on the basis of the pathologic PW: group 1, less than 30 g; group 2, 30 g or more to less than 50 g; group 3, 50 g or more to less than 80 g; and group 4, 80 g or larger. The groups were compared prospectively. Continence and sexual function were assessed using validated questionnaires.

RESULTS

Of the 375 patients, 20, 201, 123, and 31 had a PW of less than 30 g, 30 g or more to less than 50 g, 50 g or more to less than 80 g, and 80 g or larger, respectively. A significant difference was found in age and prostate-specific antigen values among the four groups (P <0.001). No significant differences in operative time, estimated blood loss, transfusion rate, hospital stay, length of catheterization, and complication incidence were observed among the four groups. The overall rate of positive surgical margins was significantly different among the groups (P = 0.002), demonstrating a trend of increasing positive surgical margins with a lower PW. Within the patients with Stage pT2, a significant increase in positive surgical margins was found with lower PWs (P = 0.026). The objective return of baseline and subjective sexual and urinary function, as determined by questionnaire scores, was not affected by the PW.

CONCLUSIONS

RLRP can be performed safely and with similar perioperative outcomes in men, regardless of the PW. We found a significant inverse relationship between surgical margin status and PW, specifically in those with Stage pT2 disease.

Age-stratified outcomes after robotic-assisted laparoscopic radical prostatectomy

We sought to evaluate post-operative return of urinary and sexual function in men undergoing robotic-assisted laparoscopic radical prostatectomy (RLRP). Prospective assessment of urinary continence and sexual function was performed in patients undergoing RLRP. Subjective assessment involved the use of the validated RAND-36 Item Health Survey/UCLA Prostate Cancer Index questionnaire. Questionnaires were completed pre-operatively and at 1, 3, 6 and 12 months post-operatively. Subset analyses were performed to assess the effect of age on functional outcomes. A total of 338 consecutive patients underwent RLRP between February 2003 and August 2005. Included patients for evaluation comprised of 21, 129, and 150 patients, aged <50, 50–59, and ≥60 years old, respectively. Kaplan–Meier curve analysis demonstrated that younger men (<60 years) achieved subjective continence significantly earlier than older age group (≥60 years) (P = 0.02). Continence rates, however, equalized among all age groups at 1 year follow-up. Younger men (<50 years) also demonstrated a quicker and greater return of sexual function (P = 0.01), which persisted through assessment at 1 year post-operatively. Our results suggest that younger men may have an earlier return of continence and potency when compared to men > 60 years. Despite this finding, continence outcomes appear to be equal among age groups after 1 year of follow-up. Moreover, men < 60 years continue to report superior potency outcomes compared to men > 60 years at 1 year post-operatively. Such findings are valuable in counseling patients undergoing RLRP.

Whole-pelvis, “mini-pelvis,” or prostate-only external beam radiotherapy after neoadjuvant and concurrent hormonal therapy in patients treated in the Radiation Therapy Oncology Group 9413 trial

PURPOSE

The Radiation Therapy Oncology Group (RTOG) 9413 trial demonstrated a better progression-free survival (PFS) with whole-pelvis (WP) radiotherapy (RT) compared with prostate-only (PO) RT. This secondary analysis was undertaken to determine whether "mini-pelvis" (MP; defined as > or = 10 x 11 cm but < 11 x 11 cm) RT resulted in progression-free survival (PFS) comparable to that of WP RT. To avoid a timing bias, this analysis was limited to patients receiving neoadjuvant and concurrent hormonal therapy (N&CHT) in Arms 1 and 2 of the study.

METHODS AND MATERIALS

Eligible patients had a risk of lymph node (LN) involvement > 15%. Neoadjuvant and concurrent hormonal therapy (N&CHT) was administered 2 months before and during RT for 4 months. From April 1, 1995, to June 1, 1999, a group of 325 patients were randomized to WP RT + N&CHT and another group of 324 patients were randomized to receive PO RT + N&CHT. Patients randomized to PO RT were dichotomized by median field size (10 x 11 cm), with the larger field considered an "MP" field and the smaller a PO field.

RESULTS

The median PFS was 5.2, 3.7, and 2.9 years for WP, MP, and PO fields, respectively (p = 0.02). The 7-year PFS was 40%, 35%, and 27% for patients treated to WP, MP, and PO fields, respectively. There was no association between field size and late Grade 3+ genitourinary toxicity but late Grade 3+ gastrointestinal RT complications correlated with increasing field size.

CONCLUSIONS

This subset analysis demonstrates that RT field size has a major impact on PFS, and the findings support comprehensive nodal treatment in patients with a risk of LN involvement of > 15%.

Association between the dihydrotestosterone level in the prostate and prostate cancer aggressiveness using the Gleason score

PURPOSE

To our knowledge the association between dihydrotestosterone in the prostate and prostate cancer aggressiveness has not yet been elucidated. We analyzed dihydrotestosterone levels in the prostate and Gleason score in patients diagnosed with clinically localized prostate cancer.

MATERIALS AND METHODS

A total of 81 patients with suspected prostate cancer underwent prostate biopsy. Serum samples were collected before biopsy. Dihydrotestosterone levels in prostatic tissue and serum were analyzed using liquid chromatography/electrospray ionization-mass spectrometry after polar derivatization.

RESULTS

A total of 47 patients were diagnosed with stages T1 to T3N0M0 prostate cancer and 34 were diagnosed with no malignancy. Of the 47 patients 32 had a Gleason score of 6 or less and 15 had a score of 7 to 10. Dihydrotestosterone in prostatic tissue in patients with Gleason score 7 to 10 disease was significantly lower than in those with Gleason score 6 or less disease (p = 0.025). Gleason score correlated with the testosterone-to-serum dihydrotestosterone ratio (rs = 0.329, p = 0.038).

CONCLUSIONS

Patients with Gleason score 7 to 10 prostate cancer have low dihydrotestosterone in the prostate, although there were no significant differences between patients with Gleason score 7 to 10 vs 6 or less prostate cancer with respect to serum androgens. Low dihydrotestosterone in cases of aggressive prostate cancer is probably sufficient to activate androgen receptor expression and propagate tumor growth.

Complete response of colorectal liver metastases after chemotherapy: does it mean cure?

PURPOSE

Most patients with colorectal liver metastases (LMs) receive systemic chemotherapy. This study aimed to determine the significance of a complete response on imaging of LMs after chemotherapy.

PATIENTS AND METHODS

Between 1998 and 2004, 586 patients were treated for colorectal LMs in one institution. Of these, 38 with the following criteria were included in the study: fewer than 10 LMs before chemotherapy; disappearance of one or several LMs on computed tomography (CT) scan and ultrasound; surgery with intraoperative ultrasound within 4 weeks of imaging; no extrahepatic disease; follow-up at least 1 year after surgery.

RESULTS

Overall, 66 LMs disappeared after chemotherapy as seen on CT scan. Persistent macroscopic disease was observed at surgery at the site of 20 of 66 LMs, despite CT scan showing a complete response. The sites of 15 initial LMs that were not visible at surgery were resected. Pathologic examination of these sites of LMs, considered in complete response, showed viable cancer cells present in 12 of 15 cases. The sites of 31 initial LMs that were not visible at surgery were left in place during surgery; after 1 year of follow-up, 23 of 31 LMs considered in complete response had recurred in situ. Overall, persistent macroscopic or microscopic residual disease or early recurrence in situ were observed in 55 (83%) of 66 LMs having a complete response on imaging.

CONCLUSION

In most patients receiving chemotherapy for colorectal LMs, a complete response on CT scan does not mean cure.

Stepping-stones to the further advancement of androgen-deprivation therapy for prostate cancer

Androgen-deprivation therapy has remained the critical therapeutic option for patients with advanced prostate cancer for over 60 years. Patients with poorly differentiated prostate cancer have low dihydrotestosterone levels in the prostate. After androgen-deprivation therapy, dihydrotestosterone levels in the prostate remain at approximately 25% of the level measured before therapy. The addition of a nonsteroidal anti-androgen to luteinizing hormone-releasing hormone analog or surgical castration significantly reduces the risk of all causes of death by 8%, which translates into a small, but significant, improvement in the 5-year survival of 2.9% over castration alone. The biologically aggressive prostate cancer cells may have an androgen receptor with heightened sensitivity to low dihydrotestosterone levels from the early stage of androgen-dependent disease. It is necessary to consider the androgen environment and the status of the androgen receptor in the prostate in order to improve the clinical efficacy of androgen-deprivation therapy and the quality of life of patients.