Significance of predicted tumor volume as a predictor of pathologic stage in patients undergoing radical prostatectomy

Percent tumor volume vs American Joint Committee on Cancer staging system subclassification for predicting biochemical recurrence in patients with pathologic T2 prostate cancer

PURPOSE

Here, we re-checked the American Joint Committee on Cancer 7th edition subclassification and confirmed the possibility of percent tumor volume as a prognostic factor for biochemical recurrence in the 8th edition subclassification.

METHODS

A total of 1073 patients with pathologic T2 stage disease who underwent radical prostatectomy were included. Exclusion criteria were neoadjuvant therapy and pathologic T3 and N1 disease. Biochemical recurrence-free survival was estimated using the Kaplan-Meier method. Cox hazard regression was used to predict biochemical recurrence.

RESULTS

According to the 7th edition subclassification, 141 patients (13.1%) had T2a, 43 (4.0%) had T2b, and 889 (82.9%) had T2c disease. The 7th edition subclassification did not differ significantly on Kaplan-Meier analysis (p = 0.502). Mean percent tumor volume was 8.7 ± 8.0% (interquartile range, 5-10%). Percent tumor volume was positively correlated with initial prostate-specific antigen, grade group, surgical margin, and T2 subclassification (all p < 0.001). The 7th edition subclassification was not a significant factor, whereas percent tumor volume was (hazard ratio, 1.023; 95% confidence interval, 1.005-1.041; p = 0.0128) on multivariate analysis. On Kaplan-Meier analysis, percent tumor volume (> 7.5% vs ≤ 7.5%) differed significantly for biochemical recurrence-free survival (p < 0.001).

CONCLUSIONS

The 7th edition pathologic T2 subclassification had poor prognostic value for biochemical recurrence in our cohort. Elimination of the 8th edition subclassification was suitable. Percent tumor volume classified biochemical recurrence prognosis in pathologic T2 stage. Therefore, percent tumor volume can be a candidate factor for the next T2 subclassification.

Pixel Prostate Software as a Reliable Tool in Depicting Spatial Distribution and Determination of the Prostate Cancer Volume

Introduction

Cancer of the prostate (PCa) is the second most common cancer-related cause of death among men and the most common non-cutaneous malignancy in Western countries. Numerous papers have been published on the topic of various aspects of this disease; however, rather little has been written on the diagnostic and prognostic value of the prostate cancer obtained from needle biopsy.

Aim

To examine the utility of Pixel Prostate software in determining the volume and topographic distribution cancer of the prostate (PCa), and to analyze it with other variables that are characteristic for PCa.

Methods

retrospectively, 75 patients data and postoperative prostate specimens were analyzed, after determining topographic distribution and cancer volume (PCa), using PixelProstate software.

Results

Mean VPCa was 6.99 cm³ (0.14-29.7; median 4.51), and mean percentage cancer volume relative to prostate volume (%VPCa) was 16% (0.1-67.2%; median 13%). 71% of the patients had T2 stage, while the rest had T3 stage. Apex involvement was present in 65% of the patients, while central zone involvement and extraprostatic extension were present in 23.5% and 22.7% of the patients, respectively. Preoperative Gleason score undergrading was present in 27 (36%) patients, while bilateral PCa finding was increased from 51% to 87%, postoperatively. The most discriminant variable according to the prediction of %VPCa>10% had preoperative bilateral needle biopsy findings, with AUC of 0.75 (<.001), with sensitivity and specificity of 84% and 70%, respectively; (+LR 2,8; PPV of 74%; NPV of 82%). %VPCa showed good correlation with prostate specific antigen (PSA) and PSA-density.

Conclusion

A possibility of precise spatial orientation and volume characterization of the PCa by PixelProstate software was shown. Simultaneously, with time, a clinician, experienced by PP software feedback, gets better insight for the planning of future prostate biopsy, as an important factor in clinical decision making.

Tumor Volume and Clinical Failure in High-Risk Prostate Cancer Patients Treated With Radical Prostatectomy

INTRODUCTION

To identify the most significant cut-off of tumor volume (TV) for prediction of clinical failure (CF) among high-risk prostate cancer (hPCa) patients.

METHODS

Within a multi-institutional cohort, 262 patients treated with radical prostatectomy (RP) for hPCa were identified. CF was defined as local recurrence or distant metastases. A time dependent ROC curve was used to evaluate the area under the curve (AUC) using TV as single marker to predict clinical failure at 10 years. We searched for the TV cut off value with the highest combined sensitivity and specificity predicting CF. Three multivariable Cox regression analyses (MVA) tested the predictors of CF after RP. Predictors of the model 1 were pre-operative PSA, pathologic stage (PT), pathologic Gleason sum (GS), surgical margin status, and lymph node invasion. Predictors of the models 2 and 3 were the same of model 1 plus TV as a continuous or dichotomous variable using the defined cutoff, respectively. Validation (leave-one-out-cross-validation-LOOCV) of each model was performed.

RESULTS

Overall, 46 (17.6%) patients experienced CF. The TV value was 6.29 ml. In MVA of models 2 and 3, PT and GS remained independent predictors of CF. Moreover, in model 2 TV (HR:1.07,) and in model 3 TV >6.29 ml (HR:2.99,) were independently associated with CF. In LOOCV, the C-index of models 1-3 were 65.53%, 71.75%, and 70.26%, respectively.

CONCLUSIONS

TV is an independent predictor of CF in hPCa patients. Patients with a TV exceeding the cut-off of 6.29 ml are more likely to develop CF. Prostate 77:3-9, 2017. © 2016 Wiley Periodicals, Inc.

Do tumor volume, percent tumor volume predict biochemical recurrence after radical prostatectomy? A meta-analysis

The aim of this meta-analysis was to explore the effects of tumor volume (TV) and percent tumor volume (PTV) on biochemical recurrence (BCR) after radical prostatectomy (RP). An electronic search of Medline, Embase and CENTRAL was performed for relevant studies. Studies evaluated the effects of TV and/or PTV on BCR after RP and provided detailed results of multivariate analyses were included. Combined hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) were calculated using random-effects or fixed-effects models. A total of 15 studies with 16 datasets were included in the meta-analysis. Our study showed that both TV (HR 1.04, 95% CI: 1.00-1.07; P=0.03) and PTV (HR 1.01, 95% CI: 1.00-1.02; P=0.02) were predictors of BCR after RP. The subgroup analyses revealed that TV predicted BCR in studies from Asia, PTV was significantly correlative with BCR in studies in which PTV was measured by computer planimetry, and both TV and PTV predicted BCR in studies with small sample sizes (<1000). In conclusion, our meta-analysis demonstrated that both TV and PTV were significantly associated with BCR after RP. Therefore, TV and PTV should be considered when assessing the risk of BCR in RP specimens.

Findings in 12-core transrectal ultrasound-guided prostate needle biopsy that predict more advanced cancer at prostatectomy: analysis of 388 biopsy-prostatectomy pairs

We analyzed 5 features on 12-core transrectal ultrasound-guided prostate needle biopsy (TRUS) to predict the extent of cancer at radical prostatectomy (RP). In 388 TRUS-RP pairs, number of positive cores (NPC), percentage of each core involved (%PC), perineural invasion (PNI), Gleason score (GS), distribution of positive cores (DPC), and preoperative prostate-specific antigen (PSA) were correlated with extraprostatic extension (EPE), seminal vesicle invasion (SVI), positive surgical margin (R1), positive lymph nodes (N1), and tumor volume. All features predicted EPE and SVI. NPC, GS, %PC, and PNI strongly predicted R1 status. RP tumor volume was directly proportional to the NPC and %PC. PSA alone and with selected biopsy findings correlated with tumor volume, stage, SVI, and N1 (P < .0001). Contiguous DPC was a significant risk for EPE and SVI (P < .0001) compared with isolated positive cores. Findings at 12-core TRUS along with preoperative PSA reliably predict advanced local disease and have practical value as guides to effective planning for surgical resections.

pT3 Predictive Factors in Patients with a Gleason Score of 6 in Prostate Biopsies

Purpose

Often, a diagnosis of pT3 is made on the basis of radical retropubic prostatectomy specimens, despite a Gleason score of 6 on the preoperative prostate biopsy. Thus, we investigated the preoperative variables in patients displaying these characteristics.

Materials and Methods

Study subjects comprised patients at our institute from 1996 to July 2010 who had exhibited a Gleason score of 6 on their prostate biopsies and had undergone a radical retropubic prostatectomy. Through univariate and multivariate analysis, we investigated pT3 predictive factors including age, preoperative prostate-specific antigen (PSA) levels, transrectal ultrasonography (TRUS)-weighted prostate volume, digital rectal examination findings, bilaterality via prostate biopsy, prostatic cancer in prostate base cores via prostate biopsy, maximum length and percent of prostatic cancer, and number of cores detected in prostatic cancer via prostate biopsy.

Results

In the univariate logistic regression mode, a PSA value of 7.4 ng/ml or higher, TRUS-weighted PSA density of 0.2 ng/ml/cc or higher, prostate cancer detected in the basal core, and prostate cancer detected in 2 or more cores out of 12 were predictive factors for extraprostatic extension. Independent predictive factors for stage pT3 were a PSA of 7.4 ng/ml or higher and prostate cancer detected in 2 or more cores out of 12.

Conclusions

In the case of patients with the foregoing risk factors, it is advisable not to perform nerve-sparing surgery but to prepare for the possibility of a pT3 stage.