Positive-block ratio in radical prostatectomy specimens is an independent predictor of prostate-specific antigen recurrence

Can Tumour Volume Percentage in Radical Prostatectomy Predict Cancer Biochemical Recurrence? Determining a Cut-off Point and Composite Risk Factors Approach

BACKGROUND

Incidence of biochemical recurrence (BCR) after radical prostatectomy is relatively high and overall survival can be poor. Debate exists whether tumour volume predicts BCR and when treatments should be administered. In this study, we aimed to i) assess the impact of tumour volume percentage (TVP) as a predictor for BCR, ii) determine TVP cut-off point for BCR and iii) evaluate single and composite predictors of BCR.

METHODS

From March 2000 to December 2013, 1777 patients underwent laparoscopic radical prostatectomy for localized prostate cancer. None received neoadjuvant or adjuvant therapy. One hundred and forty-six patients experienced BCR (range 3 months-10 years). Using D'Amico classification, 146 matched controls without BCR were compared. Liu cut-point analysis was used to identify TVP with optimal sensitivity and specificity. Single and composite BCR risk predictors were analyzed using Cox hazards regression in cases and controls.

RESULTS

Median TVP was 10% (range 1-90%). Most of BCR peaked after 3 years of follow-up. TVP ≥8% was an independent predictor of BCR with HR 1.6 (p= 0.001, 95% CI= 1.11-2.48). TVP of 8% was associated with the highest accuracy: sensitivity 74% and specificity 53% (ROC curve= 0.7). At TVP ≥8%, pathological stage pT3 was associated with 1.7-fold higher risk of BCR compared to T2. Lymph node invasion was associated with 1.4-fold higher risk of BCR compared to no invasion. Combining TVP ≥8%, pT3 and lymph node invasion, HR jumped to 3.73 (p< 0.001, 95% CI= 2.27-6.14), whereas combining TVP ≥8%, positive surgical margin and lymph node invasion, HR was 2.68 (p= 001, 95% CI= 1.50-4.77).

CONCLUSION

TVP can be used as an independent predictor of BCR after radical prostatectomy for prostate cancer. TVP cut-point of ≥8% allows the best discrimination. TVP should be considered in combination with other clinico-pathological factors to improve prediction of long-term oncological outcomes and to stratify BCR risk.

In Organ-confined Prostate Cancer, Tumor Quantitation Not Found to Aid in Prediction of Biochemical Recurrence

In the eighth edition AJCC staging, all organ-confined disease is assigned pathologic stage T2, without subclassification. We investigated whether total tumor volume (TTV) and/or maximum tumor diameter (MTD) of the index lesion are useful in improving prediction of biochemical recurrence (BCR) in pT2 patients. We identified 1657 patients with digital tumor maps and quantification of TTV/MTD who had pT2 disease on radical prostatectomy (RP). Multivariable Cox regression models were used to assess whether TTV and/or MTD are independent predictors of BCR when adjusting for a base model incorporating age, preoperative prostate-specific antigen, RP grade group, and surgical margin status. If either tumor quantification added significantly, we calculated and reported the c-index. Ninety-five patients experienced BCR after RP; median follow-up for patients without BCR was 5.7 years. The c-index was 0.737 for the base model. Although there was some evidence of an association between TTV and BCR (P=0.088), this did not meet conventional levels of statistical significance and only provided a limited increase in discrimination (0.743; c-index improvement: 0.006). MTD was not associated with BCR (P>0.9). In analyses excluding patients with grade group 1 on biopsy who would be less likely to undergo RP in contemporary practice (622 patients; 59 with BCR), TTV/MTD was not a statistically significant predictor (P=0.4 and 0.8, respectively). Without evidence that tumor quantitation, in the form of either TTV or MTD of the index lesion, is useful for the prediction of BCR in pT2 prostate cancer, we cannot recommend its routine reporting.

Effect of serum testosterone and percent tumor volume on extra-prostatic extension and biochemical recurrence after laparoscopic radical prostatectomy

Several studies have revealed that the preoperative serum testosterone and percent tumor volume (PTV) predict extra-prostatic extension (EPE) and biochemical recurrence (BCR) after radical prostatectomy. This study investigated the prognostic significance of serum testosterone and PTV in relation to EPE and BCR after laparoscopic radical prostatectomy (LRP). We reviewed 520 patients who underwent LRP between 2004 and 2012. PTV was determined as the sum of all visually estimated tumor foci in every section. BCR was defined as two consecutive increases in the postoperative prostate-specific antigen (PSA) >0.2 ng ml-1 . The threshold for serum total testosterone was 3.0 ng ml-1 . Multivariate logistic regression was used to define the effect of variables on the risk of EPE and BCR. A low serum testosterone (<3.0 ng ml-1 ) was associated with a high serum PSA, Gleason score, positive core percentage of the prostate biopsy, PTV, and all pathological variables. On multivariate analysis, similar to previous studies, the serum PSA, biopsy positive core percentage, Gleason score, and pathological variables predicted EPE and BCR. In addition, low serum testosterone (<3.0 ng ml-1 , adjusted OR, 8.52; 95% CI, 5.04-14.4, P= 0.001) predicted EPE and PTV (adjusted OR, 1.02; 95% CI, 1.01-1.05, P= 0.046) predicted BCR. In addition to previous predictors of EPE and BCR, low serum testosterone and PTV are valuable predictors of EPE and BCR after LRP.

Clinicopathological, functional, and immediate oncologic outcome assessment in men aged≤50 years with prostate cancer after robotic prostatectomy

BACKGROUND

To define the pathologic and functional outcomes of men 50 years of age and younger with prostate cancer in a contemporary robotic cohort, this study was designed.

METHODS

Patients undergoing robotic-assisted laparoscopic prostatectomy from April 2002 to April 2012 (n = 2,495) formed the base population for the current analyses. The patients were dichotomized according to their age≤50 (n = 271) and>50-year-old (n = 2,224). Clinicopathological and health-related quality-of-life outcomes were recorded and analyzed for differences. Propensity score matching was used when assessing urinary and sexual function outcome.

RESULTS

Baseline prostate-specific antigen and clinical stage were similar between men older than 50 years and those younger. Younger patients had less severe disease (D׳Amico risk and Gleason scores) and smaller prostates. Young men had higher rates of erectile function at all time points, including baseline (94% vs. 83% at 12mo, P <0.01). Continence was similar at all time points except for 6 months, where younger patients experienced a faster return than older patients and then remained constant, while older patients continued to improve (96% vs. 89%, P<0.01). After matching process, the difference in erectile function at 6-month follow-up was lost.

CONCLUSION

Most men aged 50 years and younger who received robotic-assisted laparoscopic prostatectomy had clinically significant prostate cancer. Although histopathologic and short-term oncologic outcomes were nearly identical when compared to older patients, younger men had a more rapid and superior return of erectile function.

Tumor volume adds prognostic value in patients with organ-confined prostate cancer

PURPOSE

This study was designed to assess the independent prognostic value of tumor volume (TV) and whether adding TV provides additional prognostic information for predicting biochemical recurrence (BCR) after radical prostatectomy.

METHODS

We reviewed the medical records of 1,129 patients who underwent radical prostatectomy between July 2005 and July 2011. TV was categorized as minimal (≤1.0 ml), moderate (1.1-5.0 ml), or extensive (>5.0 ml). Cox regression analysis was performed to identify independent predictors of BCR. The predictive accuracies of Cox's proportional hazard regression models with and without TV were quantified and compared using time-dependent receiver operating characteristic curve analysis.

RESULTS

Increasing TV was associated with higher prostate specific antigen, pathological Gleason score, and pathologic tumor stage. TV was an independent predictor of BCR in multivariate analysis (p<0.001). When patients were stratified by organ-confined and nonorgan-confined tumor groups, TV remained an independent predictor of BCR in organ-confined tumors (p<0.001). In the nonorgan-confined tumor group, a significant difference was found only between extensive versus minimal TV (p=0.023). The predictive accuracy of the Cox regression model increased significantly by adding TV in organ-confined tumor group (0.748 vs. 0.704, p<0.05) but not in nonorgan-confined group (0.742 vs. 0.734, p>0.05).

CONCLUSIONS

TV was an independent prognostic predictor of BCR in organ-confined prostate cancers and provided additional prognostic information with increased predictive accuracy. In contrast, TV did not increase the predictive accuracy in nonorgan-confined tumor. TV should be considered as a prognosticator in organ-confined tumors.

International Society of Urological Pathology (ISUP) Consensus Conference on Handling and Staging of Radical Prostatectomy Specimens. Working group 2: T2 substaging and prostate cancer volume

The 2009 International Society of Urological Pathology consensus conference in Boston made recommendations regarding the standardization of pathology reporting of radical prostatectomy specimens. Issues relating to the substaging of pT2 prostate cancers according to the TNM 2002/2010 system, reporting of tumor size/volume and zonal location of prostate cancers were coordinated by working group 2. A survey circulated before the consensus conference demonstrated that 74% of the 157 participants considered pT2 substaging of prostate cancer to be of clinical and/or academic relevance. The survey also revealed a considerable variation in the frequency of reporting of pT2b substage prostate cancer, which was likely a consequence of the variable methodologies used to distinguish pT2a from pT2b tumors. Overview of the literature indicates that current pT2 substaging criteria lack clinical relevance and the majority (65.5%) of conference attendees wished to discontinue pT2 substaging. Therefore, the consensus was that reporting of pT2 substages should, at present, be optional. Several studies have shown that prostate cancer volume is significantly correlated with other clinicopathological features, including Gleason score and extraprostatic extension of tumor; however, most studies fail to demonstrate this to have prognostic significance on multivariate analysis. Consensus was reached with regard to the reporting of some quantitative measure of the volume of tumor in a prostatectomy specimen, without prescribing a specific methodology. Incorporation of the zonal and/or anterior location of the dominant/index tumor in the pathology report was accepted by most participants, but a formal definition of the identifying features of the dominant/index tumor remained undecided.

The relationship between the extent of surgical margin positivity and prostate specific antigen recurrence in radical prostatectomy specimens

The presence of positive surgical margins is a negative prognostic indicator in patients undergoing prostatectomy for prostate cancer; whether the extent of the positive margins affects the clinical outcome with regards to prostate-specific antigen (PSA) recurrence remains uncertain. We evaluated the linear extent of margin positivity as a prognostic indicator in a series of radical prostatectomy specimens. One hundred seventy-four consecutive margin-positive prostatectomy specimens were evaluated. The linear extent of margin positivity was measured with an ocular micrometer and ranged from 0.05 to 75.0 mm (mean, 8.94; median, 5.0). The linear extent of margin positivity was associated with tumor volume (P = .03) but was not associated with patients' age at surgery, preoperative PSA level, prostate weight, pathologic stage, Gleason score, extraprostatic extension, seminal vesicle invasion, perineural invasion, high-grade prostatic intraepithelial neoplasia, or PSA recurrence. In the full model multiple Cox regression, significant predictors for PSA recurrence were Gleason score (P = .001) and preoperative PSA (P = .01); extent of margin positivity was not predictive of PSA recurrence (hazard ratio, 1.00; 95% confidence interval, 0.98-1.02; P = .97) nor was tumor volume a significant factor when adjusted for other covariates (P = .27). Preoperative PSA, tumor stage, and Gleason score remained significant prognostic factors in evaluating the likelihood of PSA recurrence in patients with positive surgical margins; the extent of margin positivity, however, is not a prognostic factor for PSA recurrence and should, therefore, not necessarily be included in the final report for radical prostatectomy specimens.

Percentage of Gleason pattern 4 and 5 predicts survival after radical prostatectomy

BACKGROUND

Morphologic and clinical heterogeneity within tumor grades is well recognized in prostate cancer. The objective of the current study was to determine whether the combined percentage of Gleason patterns 4 and 5 in radical prostatectomy specimens is an independent predictor of cancer-specific survival in prostate cancer patients.

METHODS

The radical prostatectomy specimens were analyzed from 504 consecutive prostate cancer patients who were treated at Indiana University Medical Center between 1990 and 1998. Various clinical and pathologic characteristics were analyzed.

RESULTS

A higher combined percentage of Gleason patterns 4 and 5 was associated with older age, higher preoperative serum prostate-specific antigen level, higher pathologic stage, positive surgical margins, extraprostatic extension of tumor, higher Gleason score, perineural invasion, and lymph node metastasis. In the multivariate Cox regression model, the combined percentage of Gleason patterns 4 and 5 was found to be an independent predictor of cancer-specific survival (P = .04).

CONCLUSIONS

The combined percentage of Gleason patterns 4 and 5 is a powerful predictor of prostate cancer-specific survival. Assessment of high-grade cancer amounts may allow for better stratification of patients into appropriate prognostic groups and treatment protocols.