Development and External Validation of Multiparametric MRI-Derived Nomogram to Predict Risk of Pathologic Upgrade in Patients on Active Surveillance for Prostate Cancer

Development and validation of a novel nomogram to avoid unnecessary biopsy in patients with PI-RADS category ≥ 4 lesions and PSA ≤ 20 ng/ml

OBJECTIVES

To develop and validate a prediction model for identifying non-prostate cancer (non-PCa) in biopsy-naive patients with PI-RADS category ≥ 4 lesions and PSA ≤ 20 ng/ml to avoid unnecessary biopsy.

PATIENTS AND METHODS

Eligible patients who underwent transperineal biopsies at West China Hospital between 2018 and 2022 were included. The patients were randomly divided into training cohort (70%) and validation cohort (30%). Logistic regression was used to screen for independent predictors of non-PCa, and a nomogram was constructed based on the regression coefficients. The discrimination and calibration were assessed by the C-index and calibration plots, respectively. Decision curve analysis (DCA) and clinical impact curves (CIC) were applied to measure the clinical net benefit.

RESULTS

A total of 1580 patients were included, with 634 non-PCa. Age, prostate volume, prostate-specific antigen density (PSAD), apparent diffusion coefficient (ADC) and lesion zone were independent predictors incorporated into the optimal prediction model, and a corresponding nomogram was constructed ( https://nomogramscu.shinyapps.io/PI-RADS-4-5/ ). The model achieved a C-index of 0.931 (95% CI, 0.910-0.953) in the validation cohort. The DCA and CIC demonstrated an increased net benefit over a wide range of threshold probabilities. At biopsy-free thresholds of 60%, 70%, and 80%, the nomogram was able to avoid 74.0%, 65.8%, and 55.6% of unnecessary biopsies against 9.0%, 5.0%, and 3.6% of missed PCa (or 35.9%, 30.2% and 25.1% of foregone biopsies, respectively).

CONCLUSION

The developed nomogram has favorable predictive capability and clinical utility can help identify non-PCa to support clinical decision-making and reduce unnecessary prostate biopsies.

Comparing histology between prostate cognitive fusion targeted biopsy and radical prostatectomy: exploring risk factors of Gleason score upgrading in Chinese patients

PURPOSE

To explore and identify the relevant clinical and pathological predictors leading to biopsy Gleason score upgrading (GSU) in cognitive fusion targeted biopsy (COG-TB) in Chinese patients.

METHODS

Clinical and pathological information of 496 patients who underwent COG-TB and radical prostatectomy (RP) in our hospital from January 2020 to September 2023 were retrospectively compiled and analyzed. In this study, we screened valuable predictors through univariable and multivariable logistic regression analyses and then constructed predictive models. We draw nomograms to visualize the predictive models. In addition, the discriminatory power of the model was assessed using receiver operating characteristic (ROC) curves. Finally, calibration curves and decision curve analysis (DCA) were used to evaluate the predictive power of the model and the net benefits it could deliver.

RESULTS

Out of the 496 patients eligible for the study, 279 had a consistent Gleason score (GS) on biopsy and postoperative GS, 191 experienced GSU, and 26 experienced downgrading. Significant associations for GSU were identified for five risk factors through multivariable logistic regression analyses, which included age, prostate volume, BMI, tumor percentage in biopsy tissue, and tumor location. Our model had excellent discriminatory power through ROC analysis. Calibration curves and DCA showed that our model was well calibrated and provided certain benefits for patient treatment decisions.

CONCLUSION

Age, prostate volume, BMI, tumor percentage in biopsy tissue, and tumor location are risk indicators for predicting GSU in COG-TB. Our prediction model is more suitable for Chinese patients and can assist in accurately evaluating biopsy GS and developing effective treatment plans.

Analysis of risk factors for Gleason score upgrading after radical prostatectomy in a Chinese cohort

Background

To study the risk factors of Gleason score upgrading (GSU) after radical prostatectomy (RP) in a Chinese cohort.

Methods

The data of 637 patients who underwent prostate biopsy and RP in our hospital from January 2014 to January 2021 were retrospectively analyzed. The age, body mass index (BMI), prostate‐specific antigen (PSA) level, testosterone (TT) level, neutrophil‐to‐lymphocyte ratio (NLR), platelet‐to‐lymphocyte ratio (PLR), eosinophil‐to‐lymphocyte ratio (ELR), aspartate aminotransferase/alanine transaminase (AST/ALT) ratio, clinical stage, the biopsy method, and pathological characteristics of specimens after biopsy and RP were collected for all patients. Univariate analysis and multivariate logistic regression analysis were used to analyze the risk factors of GSU after RP. The predictive efficacy was verified with the area under the curve (AUC) of the receiver operating characteristic (ROC) curve. We performed the analysis separately in the overall cohort and in the cohort with Gleason score (GS) = 6.

Results

In the overall cohort, 177 patients (27.79%) had GSU, and in the GS = 6 cohort, 68 patients (60.18%) had GSU. Multivariate logistic regression analysis showed that in the overall cohort, clinical stage ≥T2c (OR = 3.201, p < 0.001), the number of positive cores ≥3 (OR = 0.435, p = 0.04), and positive rate of biopsy (OR = 0.990, p = 0.016) can affect whether GS is upgraded, and the AUC of the combination of the three indicators for predicting the occurrence of GSU was 0.627. In the GS = 6 cohort, multivariate logistic regression analysis showed that clinical stage ≥T2c (OR = 4.690, p = 0.001) was a risk factor for GSU, and the AUC predicted to occur GSU is 0.675.

Conclusion

Clinical stage ≥T2c, the number of positive cores <3, and lower positive rate of biopsy are the risk factors of GSU. This study may provide some references for clinicians to judge the accuracy of biopsy pathological grading and formulate treatment strategies, but the specific effect still needs clinical practice certification.