External validation and comparison of two nomograms predicting the probability of Gleason sum upgrading between biopsy and radical prostatectomy pathology in two patient populations: a retrospective cohort study

Risk assessment of multi-factorial complications after transrectal ultrasound-guided prostate biopsy: a single institutional retrospective cohort study

BACKGROUND

Transrectal ultrasound-guided prostate biopsy (TRUSPB) is widely used to diagnose prostate cancer (PCa). The aim of this study was to evaluate the risk of multi-factorial complications (febrile genitourinary tract infection (GUTI), rectal bleeding, and urinary retention) after TRUSPB.

METHODS

N = 2053 patients were Japanese patients undergoing transrectal or transperineal TRUSPB for suspicious of PCa. To assess risk of febrile GUTI adequately, the patients were divided into four groups: low-risk patients before starting a rectal culture, low-risk patients after starting a rectal culture, high-risk patients, and patients undergoing transperineal TRUSPB. Furthermore, to identify risk of rectal bleeding and urinary retention, patients were divided into transrectal and transperineal group.

RESULTS

Febrile GUTI significantly decreased owing to risk classification. The frequency of rectal bleeding was 1.43% (transrectal: 25/1742), while it did not happen in transperineal group. The patients with rectal bleeding had a significantly lower body mass index (BMI) (P < 0.01). The frequency of urinary retention was 5.57% (transrectal: 97/1742), while it did not happen in transperineal group. The patients with urinary retention had a significantly higher prostate-specific antigen (PSA) (P = 0.01) in transrectal group.

CONCLUSIONS

Risk classification, rectal swab culture, and selected antimicrobial prophylaxis for transrectal TRUSPB were extremely effective to reduce the risk of febrile GUTI. Furthermore, lower BMI and higher PSA were novel clinical predictors for rectal bleeding and urinary retention, respectively. When urologists perform transrectal TRUSPB to their patients, they can correctly understand and explain each complication risk to their patients based on these novel risk factors.

Quantitative evaluation of the relative apparent diffusion coefficient values on multiparametric magnetic resonance imaging to predict higher Gleason score prostate cancer

INTRODUCTION

Apparent diffusion coefficient (ADC) values on multiparametric magnetic resonance imaging (mpMRI) have been reported to correlate with high-Gleason score (GS) prostate cancer. However, the relative ADC values between tumor lesions and normal tissue have been suggested as more suitable than the absolute ADC values for evaluation of diffusion abnormalities, because absolute ADC values are susceptible to differences in scanners or scanner settings. The present study evaluated the usefulness of the relative assessment of ADC values between tumor lesions and normal tissue on preoperative mpMRI for the prediction of high-risk prostate cancer on radical prostatectomy specimens.

MATERIALS AND METHODS

A retrospective analysis of 48 men who underwent radical prostatectomy between January 2013 and December 2014 was conducted. MpMRI was performed with a 3.0-T scanner using b-values of 0 and 1500 s/mm². ADC values of the tumor (ADC_TUMOR) and normal prostate and the relative ADC tumor/normal ratio (ADC_TNR) were evaluated by two radiologists.

RESULTS

The inter-rater reliability between two radiologists for ADC_TUMOR measurement was high, with Pearson's r = 0.982. There was no difference in ADC_TUMOR between GS ≤7 and GS ≥8. In contrast, ADC_TNR was significantly lower in GS ≥8 than in GS ≤7. ROC curves of ADC_TNR to predict higher GS (≥8) showed better classification performance (AUC = 0.8243, p = .0012 by radiologist A and AUC = 0.7961, p = .0031 by radiologist B) than of ADC_TUMOR.

CONCLUSIONS

The relative assessment of ADC values between tumor lesions and normal tissue could improve the detection rate of high-risk prostate cancers.

External validation of two web-based postoperative nomograms predicting the probability of early biochemical recurrence after radical prostatectomy: a retrospective cohort study

The present study aimed to validate and compare the predictive accuracies of the Memorial Sloan Kettering Cancer Center (MSKCC) and Johns Hopkins University (JHU) web-based postoperative nomograms for predicting early biochemical recurrence (BCR) after radical prostatectomy (RP) and to analyze clinicopathological factors to predict early BCR after RP using our dataset. The c-index was 0.72 (95% confidence (CI): 0.61-0.83) for the MSKCC nomogram and 0.71 (95% CI: 0.61-0.81) for the and JHU nomogram, demonstrating fair performance in the Japanese population. Furthermore, we statistically analyzed our 174 patients to elucidate prognostic factors for early BCR within 2 years. Lymphovascular invasion (LVI) including lymphatic vessel invasion (ly) was a significant predictor of early BCR in addition to common variables (pT stage, extraprostatic extension, positive surgical margin and seminal vesicle invasion). LVI, particularly ly, may provide a good predictor of early BCR after RP and improve the accuracy of the nomograms.

Nomogram analysis and external validation to predict the risk of lymph node metastasis in gastric cancer

Aim

To identify risk factors for lymph node metastasis using a nomogram for gastric cancer patients to predict lymph node metastasis.

Results

The Chi-square test and the logistic regression showed that the Boarrmann type, preoperative CA199 level, T stage and N stage by CT scan were independent risk factors. The concordance index (C-index) was 0.786 in the internal validation of the Nomogram model. In the external validation, the C-index was 0.809, and the AUC was 0.894. The total accuracy of the prediction was 82.2%, and the false-negative rate was 5.4% with a cut-off value set at 0.109.

Materials and Methods

The study consisted of 451 patients with a histological diagnosis of gastric cancer with 0 or 1 lymph node metastasis from the Sun Yat-sen University Cancer Center as the development set, and the validation set consisted of 186 gastric cancer patients from the Sixth Affiliated Hospital of Sun Yat-Sen University. A Chi-square test and a logistic regression analysis were used to compare the clinicopathological variables and lymph node metastasis. The C-index and ROC curve were computed for comparisons of the nomogram's predictive ability.

Conclusions

We developed and validated a nomogram to predict lymph node metastasis in gastric cancer before surgery. This nomogram can be broadly applied, even in general hospitals, and is useful for decisions regarding treatment programs for patients.

Clinical predictors for high-grade bladder cancer before first-time transurethral resection of the bladder tumor: a retrospective cohort study

The aim of this study was to identify the clinical predictors related to the risk of high-grade bladder cancer before first-time transurethral resection of the bladder tumor (TUR-Bt) and to externally validate the accuracy of Shapur's nomogram predicting the risk of high-grade bladder cancer in Japanese patients. As a result, episode of gross hematuria (odds ratio: 2.68, P = 0.02), larger tumor size (odds ratio: 1.89, P < 0.01) and positive urinary cytology (odds ratio: 8.34, P < 0.01) were found to be significant predictors for high-grade bladder cancer. Furthermore, the nomogram showed a high predictive accuracy in our Japanese population (area under the curve: 0.79). Clinicians will be able to predict high-grade bladder cancer using the common factors in Shapur's study and ours, such as tumor size and urinary cytology, and gross hematuria as the additional factor first identified here to decide priorities for the treatment of patients diagnosed with bladder cancer.