The role of pre-biopsy mpMRI in lymph node staging for prostate cancer

INTRODUCTION

Prostate cancer (PCa) staging is an integral part in the management of prostate cancer. The gold standard for diagnosing lymph node invasion is a surgical lymphadenectomy, with no superior imaging modality available at the clinician's disposal. Our aim in this study is to identify if a pre-biopsy multiparametric MRI (mpMRI) can provide enough information about pelvic lymph nodes in intermediate and high risk PCa patients, and whether it can substitute further cross sectional imaging (CSI) modalities of the abdomen and pelvis in these risk categories.

METHODS

Patients with intermediate and high risk prostate cancer were collected between January 2015 and June 2019, while excluding patients who did not undergo a pre-biopsy mpMRI or a CSI. Date regarding biopsy result, PSA, MRI results, CSI imaging results were collected. Using Statistical Package for the Social Sciences (SPSS) version 24.0, statistical analysis was conducted using the Cohen's Kappa agreement for comparison of mpMRI with CSI. McNemar's test and receiver operator curve (ROC) curve were used for comparison of sensitivity of both tests when comparing to the gold standard of lymphadenectomy.

RESULTS

A total of 143 patients fit the inclusion criteria. We further stratified our patients into according to PSA level and Gleason score. Overall, agreement between mpMRI and all CSI was 0.857. When stratifying patients based on Gleason score and PSA, the higher the grade or PSA, the higher agreement between mpMRI and CSI. The sensitivity of mpMRI (73.7%) is similar to CSI (68.4%). When comparing CSI sensitivity to that of mpMRI, no significant difference was present by utilizing the McNemar test and very similar receiver operating characteristic curve.

CONCLUSION

A pre-biopsy mpMRI can potentially substitute further cross sectional imaging in our cohort of patients. However, larger prospective studies are needed to confirm our findings.

Comparative analysis of histopathological subtypes of renal cell carcinoma in the Middle East compared to other world regions

Introduction

Renal cell carcinoma (RCC) has various histopathological tumor subtypes which have a significant implication on the oncological outcome of these patients. We aimed to evaluate the distribution of RCC subtypes presenting at a tertiary care center in the Middle East, in comparison to the distribution reported in different geographic areas worldwide.

Methods

A retrospective chart review was conducted on all patients who underwent partial or radical nephrectomy for RCC at the American University of Beirut Medical Center between January 2012 and January 2018. Data on histologic subtypes were compiled and compared to representative series from different continents.

Results

One hundred and seventy-nine patients with RCC were identified, of whom 122 (68.2%) were classified as clear cell, 30 (16.8%) as papillary, 17 (9.5%) as chromophobe, and 10 (5.6%) as unclassified. When compared to other regions of the world, this Middle Eastern series demonstrated a higher prevalence of the chromophobe subtype compared to Western populations (9.5% in the Middle East vs. 5.3% in the US and 3.1% in Europe) and a lower prevalence of clear cell subtype (68.2% in the Middle East vs. 78.7% in the US and 85.8% in Europe). Conversely, there was a higher prevalence of papillary RCC in the Middle East (16.8%) compared to North America (13.1%, 95% confidence interval [CI]: 12.7-13.6), Europe (11.1%, 95% CI: 10.0-12.1), and Australia (10.2%). The prevalence of chromophobe and clear cell RCC in the Middle East was similar to that reported in South America.

Conclusions

The distribution of RCC subtypes in this Middle Eastern cohort was significantly different from that reported in the Western hemisphere (Europe and the US) but similar to that reported in South America and Australia. These findings may point to a possible genetic predisposition underlying the global variation in distribution.

Development of a novel nomogram incorporating platelet-to-lymphocyte ratio for the prediction of lymph node involvement in prostate carcinoma

OBJECTIVE

The available nomograms used to predict lymph node involvement (LNI) are not comprehensive. We sought to derive a novel nomogram incorporating the platelet to lymphocyte ratio (PLR) to predict LNI and compare its performance to validated preoperative risk nomograms in a cohort of men undergoing robotic-assisted radical prostatectomy at our institution.

METHODS

Our electronic health record was queried for patients who underwent robotic-assisted radical prostatectomy with bilateral pelvic lymphadenectomy between 2013 and 2019. A bootstrapped multivariate logistic regression model was constructed for the predictors of LNI while adjusting for other covariates. Then, we used the derived logistic regression formula to estimate each patient's risk (%) for LNI. Individualized risks were also calculated using the following verified nomograms: Briganti-2012, Cagiannos, Godoy, and Memorial Sloan Kettering Cancer Center. Subsequently, we plotted the risks for our nomogram and the 4 verified nomograms into receiver operating characteristics curves. We reported the area under the curve (AUC) for each of the 5 nomograms and the corresponding 95% confidence interval (CI).

RESULTS

The cohort included 173 patients, of which 13.9% demonstrated LNI. LNI was associated with higher preoperative prostate-specific antigen (PSA) ≥ 10 [odds ratio [OR] = 4.89; 95% confidence interval [CI] (1.42-16.83)], higher grade (WHO group ≥ 3)[19.21; (2.23-195.25)], and higher percentage of positive biopsy cores (≥60%) [3.38, (1.04-11.00)]. With every 30-unit increase in PLR the risk of LNI increased by 47%. The nomogram derived from our data had the highest AUC [(AUC 0.877; 95% CI (0.806-0.947)]. The Memorial Sloan Kettering Cancer Center and Briganti 2012 displayed almost congruent ability [0.836; 95% CI (0.758-0.915)] and [0.827; (0.752-0.902)] to identify patients with positive nodes in our cohort with perfect sensitivity and negative predictive value.

CONCLUSION

The nomogram incorporating PLR demonstrated 94.7% sensitivity to predict LNI and avoided pelvic lymphadenectomy in half of the patients at a cut-off between 6.5% and 8.5%. A prospective study with a larger sample is needed to validate our findings.

An evaluation of the timing of surgical complications following radical prostatectomy: Data from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP)

Objective

To perform a time-to-complication analysis for radical prostatectomy (RP) and computing risk factors for these complications, as RP is established as a first-line treatment for localised prostate cancer with excellent oncological outcomes but is not without its complications.

Patients and methods

We used the National Surgical Quality Improvement Program (NSQIP) database to analyse data of patients who underwent RP, between 2008 and 2015, with the primary endpoint of time-to-complications. Categorical variables were analysed using descriptive statistics and continuous variables were recorded as medians and interquartile ranges (IQRs) such as timing of complications. Multivariable regression analyses were used to analyse time-to-complication and its effect on other outcomes. A P < 0.05 was defined as statistically significant.

Results

The overall 30-day complication rate was 7.54% and was equally distributed before and after discharge. Bleeding/transfusion (3.37%), urinary tract infection (1.58%), deep venous thrombosis (DVT; 0.74%), and wound infection (1.08%) were the five most common complications after RP. The median (IQR) time-to-complication unique for each complication was: bleeding/transfusion occurred on the same operative day (1), renal complications occurred at 4 (2–6) days, sepsis at 12 (6.5–17.5) days, DVT at 11 (5.5–16.5) days, pneumonia at 4 (0.5–7.5) days, and cardiac arrest occurred at 5 (1.75–8.25) days. After discharge complications were associated with greater odds of re-admission (odds ratio [OR] 16.40, P < 0.001), but associated with a lesser length of stay (OR – 3.33, P < 0.001) when compared to pre-discharge complications.

Conclusion

Several risk factors predict pre- and post-discharge complication rates. Knowledge regarding the timing of complications and their respective risk factors should improve patient–physician communication and prediction, and thus patient care.

Abbreviations

ACS: American College of Surgeons; BMI: body mass index; DM: diabetes mellitus; DVT: deep venous thrombosis; Hct: haematocrit; IQR: interquartile range; LOS: length of stay; NSQIP: National Surgical Quality Improvement Program; OR: odds ratio; RP: radical prostatectomy

A novel approach to treatment of priapism refractory to non-surgical methods: A single-case experience

Ischaemic priapism is a rarely encountered urological emergency that can lead to erectile dysfunction if not treated. Treatment strategies for ischaemic priapism include: cavernosal sympathomimetic injections; percutaneous shunts; and surgical procedures including shunts and penile prostheses. We present a case of a middle-aged man presenting with ischaemic priapism refractory to cavernosal injections and percutaneous T-shunt procedure. After refusal of surgery, a continuous cavernosal infusion of phenylephrine was successfully performed with resolution of erection and no sequelae. For the treatment of ischaemic priapism, adherence to management guidelines should be encouraged; however, it is still a disease entity that is not well understood and new treatment protocols may have a role in the future.

Abbreviation: ED: erectile dysfunction