Differences in the rate of lymph node invasion in men with clinically localized prostate cancer might be related to the continent of origin

Predictive models in cancer management: A guide for clinicians

BACKGROUND

Predictive tools in cancer management are used to predict different outcomes including survival probability or risk of recurrence. The uptake of these tools by clinicians involved in cancer management has not been as common as other clinical tools, which may be due to the complexity of some of these tools or a lack of understanding of how they can aid decision-making in particular clinical situations.

AIMS

The aim of this article is to improve clinicians' knowledge and understanding of predictive tools used in cancer management, including how they are built, how they can be applied to medical practice, and what their limitations may be.

METHODS

Literature review was conducted to investigate the role of predictive tools in cancer management.

RESULTS

All predictive models share similar characteristics, but depending on the type of the tool its ability to predict an outcome will differ. Each type has its own pros and cons, and its generalisability will depend on the cohort used to build the tool. These factors will affect the clinician's decision whether to apply the model to their cohort or not.

CONCLUSIONS

Before a model is used in clinical practice, it is important to appreciate how the model is constructed, what its use may add over and above traditional decision-making tools, and what problems or limitations may be associated with it. Understanding all the above is an important step for any clinician who wants to decide whether or not use predictive tools in their practice.

Intermediate-term cancer control outcomes in prostate cancer patients treated with robotic-assisted laparoscopic radical prostatectomy: a multi-institutional analysis

PURPOSE

Cancer control outcomes following robot-assisted radical prostatectomy (RARP) for prostate cancer (PCa) remain inadequately addressed over intermediate-term (≥5-year) follow-up. We examined biochemical recurrence-free survival (BCRFS), clinical recurrence-free survival (CRFS), and cancer-specific survival (CSS) in a multi-institutional cohort of men undergoing RARP for localized PCa.

MATERIALS AND METHODS

A total of 5670 PCa patients undergoing RARP ± pelvic lymph node dissection as primary treatment modality at three tertiary care centers between 2001 and 2010 were analyzed. BCRFS, CRFS, and CSS were estimated using the Kaplan-Meier method. Cox proportional hazards model tested their association with available preoperative and postoperative parameters.

RESULTS

43.6 and 15.1 % of patients had D'Amico intermediate- and high-risk disease, respectively. Over a mean (median) follow-up of 56 (50.4) months, 797 men had a BCR, 78 men had CR, and 32 men died of PCa. Actuarial BCRFS, CRFS, and CSS, respectively, were 83.3, 98.6, and 99.5 % at 5-year; 76.5, 97.5, and 98.7 % at 8-year; and 73.3, 96.7, and 98.4 % at 10-year follow-ups. Only 1.7 % of patients received any adjuvant treatment. Preoperative prostate-specific antigen (PSA) and biopsy Gleason score (GS) were independent clinical predictors of BCRFS, CRFS, and CSS, while postoperatively positive surgical margin, pathological GS, pathological stage, and lymph node invasion were significantly associated with BCR and CR (all p < 0.05).

CONCLUSIONS

Cancer control outcomes of RARP appear comparable to those reported for open and laparoscopic RP in previous literature, despite low overall rate of adjuvant treatment. Disease severity and preoperative PSA may aid in risk prognostication and defining postoperative follow-up protocols.

Adherence to the lymphadenectomy recommendations of the 2009 clinical guidelines in the 2010 National Prostate Cancer Registry

OBJECTIVE

To assess the adherence to the recommendations of the 2009 clinical guidelines in the implementation of lymphadenectomy during radical prostatectomy and analysis of the variables that influence this decision in the 2010 National Prostate Cancer Registry.

MATERIAL AND METHOD

Analysis of 1,272 patients who underwent prostatectomy in 25 national hospitals. Patient classification according to the pathological node-positive (pN+) risk criteria included in the clinical guidelines of the European Association of Urology (EAU) and National Comprehensive Cancer Network (NCCN). Calculation of the raw agreement and index of agreement kappa. Logistic regression to assess the predictors in the decision to perform lymphadenectomy.

RESULTS

Lymphadenectomy was performed on 225 (17.7%) patients, with a variability among centers of 0-62.2% (p<.001). There was lymphocytic invasion (pN+) in 17 (7.5%) patients. The raw agreement with the EAU-09 clinical guidelines was .672 (.48-.96 in the various centers), and the kappa index was .289. The raw agreement with the NCCN-09 clinical guidelines was.814 (.51-1 in the various centers), and the kappa index was .228. In the multivariate analysis, the independent predictors for performing lymphadenectomy were the Gleason score, the clinical stage, the prostate-specific antigen, the hospital center and the surgical approach route to prostatectomy (all P<.001).

CONCLUSIONS

In our study, adherence to the recommendations of the clinical guidelines on the implementation of lymphadenectomy was moderate. When deciding on lymphadenectomy, the determinants (in addition to the classic clinical variables) were the approach route and the hospital where the prostatectomy was performed.

Algorithm for selecting men for pelvic lymph node dissection (PLND) during radical prostatectomy based on clinical risk factors in an Australian population

OBJECTIVE

To define selection criteria for pelvic lymph node dissection (PLND) based on a contemporary Australian cohort of men with clinically localised prostate cancer undergoing radical prostatectomy (RP) with PLND, as stage migration of prostate cancer has led to re-evaluation of the role of PLND at the time of RP.

PATIENTS AND METHODS

In all, 200 consecutive men treated by one surgeon between 2000 and 2005 with open RP and PLND. The clinical and pathological data were extracted by retrospective chart review. Associations between clinical predictors and LN positivity were assessed by logistic regression analysis.

RESULTS

Overall, there were LN metastases were in 10 (5%) men. The LN positivity rate was significantly associated with biopsy Gleason score, preoperative prostate-specific antigen (PSA) concentration and percentage of positive cores (PPC), with respective odds ratios (OR) (95% confidence interval [CI]) of 3.70 (1.98-6.92), 1.11 (1.04-1.19) and 1.04 (1.01-1.06) Trend toward significant association with clinical stage (OR 1.75, 95% CI 0.97-3.13) On multivariate analysis, PSA concentration and biopsy Gleason score were significant predictors of LN disease. All 10 men with LN metastases came from a high-risk group of 96, identifiable by having at least one of the following: stage ≥ cT2b, biopsy Gleason score ≥ 4+3, PSA concentration of ≥ 10 ng/mL or PPC of ≥ 38%.

CONCLUSIONS

The risk of LN metastases depends upon well-defined clinical risk factors of stage, biopsy Gleason score, PSA concentration and PPC. The present data suggests a simple risk-stratification method, using these risk factors, of identifying men to have PLND at the time of RP.

Head-to-head comparison of three commonly used preoperative tools for prediction of lymph node invasion at radical prostatectomy

OBJECTIVE

A formal validation and head-to-head comparison of the National Comprehensive Cancer Network (NCCN) practice guideline lymph node invasion (LNI) nomogram, Partin tables, and D'Amico risk-classification was conducted for prediction of LNI at radical prostatectomy (RP).

METHODS

We focused on 20,877 patients treated with RP and pelvic lymph node dissection (PLND) between 2004 and 2006 within the Surveillance, Epidemiology and End Results database. The discrimination of the 3 tools in predicting histologically confirmed LNI was quantified using the area under the curve (AUC). Calibration plots were used to graphically depict the performance characteristics of the examined tools. In addition, we relied on decision curve analyses to compare the 3 models directly in a head-to-head fashion.

RESULTS

Overall, 2.5% of patients had LNI. The NCCN LNI nomogram (AUC 82%) outperformed the Partin tables (73%) and the D'Amico risk-classification (75%) for prediction of LNI. Calibration plots revealed that all 3 tools overestimated the risk of LNI. Partin tables showed the highest net-benefit for probability threshold range between 1% and 4%. Conversely, the NCCN LNI nomogram showed the highest net-benefit for the remaining threshold probabilities.

CONCLUSION

The NCCN LNI nomogram had the highest discrimination accuracy. However, using the decision curve analysis, the Partin tables demonstrated the highest net benefit when a threshold probability of LNI is <4%. In contrast, the NCCN LNI nomogram had the highest net benefit when the threshold probability used to perform PLND is greater than 4%.

Predictive models before and after radical prostatectomy

CONTEXT

In the last 10 years, several user-friendly predictive tools have been developed to help clinicians in decision-making process before and after radical prostatectomy.

OBJECTIVE

To review the most known and used predictive models in pre-operative and post-operative setting.

EVIDENCE ACQUISITION

A structured, comprehensive literature review was performed using data retrieved from recent review articles, original articles, and abstracts. Used keywords were predictive models, nomograms, look-up tables, classification and regression-tree analysis, artificial neural networks, and radical prostatectomy.

EVIDENCE SYNTHESIS

A great amount of predictive models has been provided in oncology setting: nomograms, look-up tables, classification and regression-tree analysis, propensity scores, risk-group stratification models, and artificial neural networks. Pre-surgery predictive tools offer the opportunity of getting the most evidence-based and individualized selection of available treatment alternatives. Post-operative predictive models usually provide higher accuracy relative to the pre-surgery models.

CONCLUSIONS

Decisions and treatment should be tailored to each individual patient and to the specific characteristics of patients. A number of available predictive models represent a tool to provide accurate prediction of cancer natural history and to improve patients' care.

Validation of Epstein criteria of insignificant prostate cancer in Middle East patients

BACKGROUND

Since introduction of Contemporary Epstein criteria, it has been studied and validated in many countries and nations. However, they were not validated in Middle East patients up till now.

AIM OF THE WORK

To validate the Contemporary Epstein criteria in Middle East patients.

MATERIALS AND METHODS

On past 8 years, 70 cases underwent radical prostatectomy for T1c prostate cancer. Contemporary Epstein criteria were applied retrospectively on prostatic biopsies. Among our patients, 35 cases met the criteria for clinically insignificant prostate cancer. Pathological revision of the prostatic biopsies, definitive prostatectomy specimens and re-staging were done by single pathologist. Assessment of recurrence rate was done. Up and down grading of the Gleason scoring was studied.

RESULTS

The preoperative data and biopsy results using the Contemporary Epstein criteria were fulfilled on 35 cases. On definitive pathology; 16 cases (45.7%) had Gleason score >6, while 8.6% of cases are non-organ confined (2 cases and 1 case with extra- capsular and Seminal vesicles infiltrations, respectively). Both lobes were involved in 20 cases. Moreover, 40% (14 cases) showed upgrading of the score. Lymphatic permeation could be recognized in four cases. Mean follow-up time 88.1 months, 8.6% cases develop metastasis.

CONCLUSION

Whenever Epstein criteria are applied in Middle East patients, the decision of active surveillance based for clinically insignificant prostate cancer (who met the Epstein criteria) will miss nearly 46% of unfavorable prostate cancer. As well as a risk of later metastasis could be in 8.6% of them.

Cytoreductive partial nephrectomy does not undermine cancer control in metastatic renal cell carcinoma: a population-based study

OBJECTIVES

We examined the population-based rates of cancer-specific survival in patients with metastatic renal cell carcinoma (MRCC) treated with either partial (PN) or radical cytoreductive nephrectomy (RN).

METHODS

Patients diagnosed with MRCC and treated with either PN or RN were identified within nine SEER cancer registries. Matched and unmatched Kaplan-Meier survival analyses, as well as multivariable Cox regression models compared the effect of RN (n = 1997, 97.8%) vs. PN (n = 46, 2.2%) on cancer-specific survival (CSS). Covariates consisted of age, gender, community type (rural vs urban), race, Surveillance, Epidemiology, and End Results (SEER) registry, tumor size and year of diagnosis.

RESULTS

In multivariable unmatched Cox regression analyses, no statistically significantly difference was found in CSS between the two groups (hazard ratio [HR] 1.40, P = .16). Similarly, no difference in CSS was found in the matched analyses (HR 1.35, log rank P = .34).

CONCLUSION

Cytoreductive PN does not appear to undermine survival in patients with MRCC.

Radical prostatectomy for incidental (stage T1a-T1b) prostate cancer: analysis of predictors for residual disease and biochemical recurrence

BACKGROUND

Controversies exist about the most appropriate management for patients with incidental prostate cancer after surgery for benign prostatic hyperplasia (BPH).

OBJECTIVES

To test the accuracy of preoperative clinical variables in predicting the presence of residual disease and biochemical recurrence in patients with incidental prostate cancer treated with radical retropubic prostatectomy.

DESIGN, SETTING, AND PARTICIPANTS

We analyzed 126 T1a-T1b prostate cancers diagnosed at surgery for BPH between 1995 and 2007.

INTERVENTION

All patients underwent radical retropubic prostatectomy within 6 mo of surgery for BPH.

MEASUREMENTS

Univariate and multivariate logistic regression models addressed the association between the predictors (age, prostate-specific antigen [PSA] before and after surgery for BPH, T1a-T1b stage, prostate volume, and Gleason score at surgery for BPH) and the presence of residual cancer at radical retropubic prostatectomy. Cox proportional hazards regression analyses tested the relationship between the same predictors and the rate of biochemical recurrence after radical retropubic prostatectomy.

RESULTS AND LIMITATIONS

Seventy-five (59.5%) patients were stage T1a and 51 (40.5%) were stage T1b. At radical retropubic prostatectomy, 21 (16.7%) patients were pT0 and seven (5.6%) patients had extraprostatic disease (pT3). PSA before and after surgery for BPH and Gleason score at surgery for BPH were the only independent predictors of residual cancer at radical retropubic prostatectomy (all p<0.04). Stage (T1a vs T1b) did not predict residual cancer or the rate of biochemical recurrence. With a mean follow-up of 57 mo, the 5- and 10-yr biochemical recurrence-free survival rates were 92% and 87%, respectively. PSA after surgery for BPH and Gleason score at surgery for BPH were the only significant multivariate predictors of biochemical recurrence (all p<0.04). The main limitation of this study is the requirement of an external validation before implementation of the clinical recommendations.

CONCLUSION

PSA measured before and after surgery for BPH and Gleason score at surgery for BPH were the only significant predictors of the presence of residual cancer at radical retropubic prostatectomy. PSA measured after surgery for BPH and Gleason score at surgery for BPH were the only independent predictors of biochemical recurrence after radical retropubic prostatectomy.

Validation of the contemporary epstein criteria for insignificant prostate cancer in European men

OBJECTIVES

The Epstein criteria represent the most widely used scheme for prediction of clinically insignificant prostate cancer (PCa). However, they were never validated in European men. We assessed the rate of unfavorable prostate cancer (Gleason 7-10 or non-organ-confined disease) in a cohort of 366 men who fulfilled the Epstein clinically insignificant PCa criteria.

METHODS

Between 1996 and 2006, 2580 men underwent radical prostatectomy at a single academic European institution. Of those, 366 fulfilled the contemporary Epstein clinically insignificant PCa criteria. Analyses targeted the rate of pathologically unfavorable prostate cancer, defined as either Gleason sum 7-10 or non-organ-confined disease, or a combination of these characteristics in patients with clinically insignificant PCa.

RESULTS

Gleason 7-10 prostate cancer at radical prostatectomy was found in 88 patients (24%) with clinically insignificant PCa. In addition, 30 (34.1%) of the 88 patients harboured non-organ-confined disease. Consequently, the contemporary Epstein criteria for clinically insignificant PCa were inaccurate in 24% of patients.

CONCLUSIONS

The Epstein clinical insignificant PCa criteria may underestimate the true nature of prostate cancer in as many as 24% of European patients. Therefore, caution is advised when treatment decisions are based solely on these criteria.