External validation of nomogram predicting the probability of specimen-confined disease (pT2-3a, R0N0) in patients undergoing radical prostatectomy and pelvic lymph node dissection

How radical prostatectomy procedures have changed over the last 10 years in Italy: a comparative analysis based on more than 1500 patients participating in the MIRROR-SIU/LUNA and the Pros-IT CNR study

PURPOSE

Therapeutic strategies for prostate cancer (PCa) have been evolving dramatically worldwide. The current article reports on the evolution of surgical management strategies for PCa in Italy.

METHODS

The data from two independent Italian multicenter projects, the MIRROR-SIU/LUNA (started in 2007, holding data of 890 patients) and the Pros-IT-CNR project (started in 2014, with data of 692 patients), were compared. Differences in patients' characteristics were evaluated. Multivariable logistic regression models were used to identify characteristics associated with robot-assisted (RA) procedure, nerve sparing (NS) approach, and lymph node dissection (LND).

RESULTS

The two cohorts did not differ in terms of age and prostate-specific antigen (PSA) levels at biopsy. Patients enrolled in the Pros-IT-CNR project more frequently were submitted to RA (58.8% vs 27.6%, p < 0.001) and NS prostatectomy (58.4% vs. 52.9%, p = 0.04), but received LND less frequently (47.7% vs. 76.7%, p < 0.001), as compared to the MIRROR-SIU/LUNA patients. At multivariate logistic models, Lower Gleason Scores (GS) and PSA levels were significantly associated with RA prostatectomy in both cohorts. As for the MIRROR-SIU/LUNA data, clinical T-stage was a predictor for NS (OR = 0.07 for T3, T4) and LND (OR = 2.41 for T2) procedures. As for Pros-IT CNR data, GS ≥ (4 + 3) and positive cancer cores ≥ 50% were decisive factors both for NS (OR 0.29 and 0.30) and LND (OR 7.53 and 2.31) strategies.

CONCLUSIONS

PCa management has changed over the last decade in Italian centers: RA and NS procedures without LND have become the methods of choice to treat newly medium-high risk diagnosed PCa.

External evaluation of the Briganti nomogram to predict lymph node metastases in intermediate-risk prostate cancer patients

PURPOSE

The Briganti nomogram can be used with a threshold of 5% to decide when to offer lymph node dissection during radical prostatectomy. The objective of the study was to assess the accuracy of the Briganti nomogram on intermediate-risk prostate cancer patients managed in a single academic department.

METHODS

We retrospectively reviewed the files of all patients managed by radical prostatectomy (RP) and bilateral pelvic lymph node dissection (BPLND) in our center between 2005 and 2017. The overall accuracy of the model in predicting metastatic lymph node disease was quantified by the construction of a receiver-operator characteristic (ROC) curve. A calibration plot was drawn to represent the relationship between the predicted and observed frequencies.

RESULTS

We included 285 patients, among whom 175 (61.4%) were classified as intermediate risk as defined by D'Amico. The median follow-up was 60 (34-93) months. Twenty-seven patients (9.5%) were diagnosed with lymph node metastases. The median number of lymph nodes removed was 10 (7-14). The mean Briganti score was 19.3% in patients with lymph node involvement (LNI) and 6.3% in patients without LNI. Focusing on intermediate-risk patients, 91(52%) and 84 (48%) had a Briganti score < 5% and ≥ 5%, respectively, among whom 6 (6.6%) and 7(8.3%) had lymph node metastases. The accuracy of the score was low for intermediate risk patients with an area under the curve (AUC) of 53.1% (95% CI 0.45-0.61).

CONCLUSION

The Briganti nomogram in our retrospective cohort showed low accuracy for the prediction of lymph node involvement in an intermediate-risk prostate cancer population.

Assessing the clinical benefit of a nomogram to predict specimen-confined disease at radical prostatectomy in patients with high-risk prostate cancer: An external validation

OBJECTIVE

The objective of the current study was to test generalizability and clinical value of a recently published nomogram to predict specimen-confined disease (SCD, pT2-pT3a+R0+pN0) at radical prostatectomy (RP) in patients with clinical high-risk prostate cancer (HRPCa). The nomogram allows improved decision making with curative intent within this heterogeneous patient cohort, which is important, as RP in patients with clinical HRPCa remains a topic of controversy.

METHODS

We externally validated the nomogram in 1,669 men with clinical HRPCa who underwent RP and extended pelvic lymph node dissection between 1992 and 2011. A Kaplan-Meier analysis to estimate 5- and 10-year biochemical recurrence-free survival was performed. To investigate the SCD model׳s performance, the previously reported regression coefficients of the SCD nomogram were applied. Within loess calibration plots, the extent of overestimation or underestimation was graphically explored. Finally, decision curve analysis (DCA) to assess the clinical value of the SCD nomogram was performed.

RESULTS

Overall, 49% of men showed SCD after RP. The 5- and 10-year biochemical recurrence rates for men with SCD were 66% and 56%, respectively, vs. 32% and 20%, respectively, for men without SCD (log-rank test P<0.001). External validation demonstrated comparable accuracy in relation to accuracy derived from internal validation (68.1% vs. 72.0%). Calibration was suboptimal, showing a tendency to underestimate SCD probability. In DCA, the nomogram׳s usage was associated with a clinical net benefit relative to both treating all and none.

CONCLUSIONS

Within our cohort, the nomogram׳s use was associated with a clinical net benefit according to DCA. However, one-third of men were falsely classified as having SCD or non-SCD. Nevertheless, in the absence of superior tools, the SCD nomogram represents a useful clinical decision aid.

Clinical Outcome of Patients with Lymph Node-Positive Prostate Cancer following Radical Prostatectomy and Extended Sentinel Lymph Node Dissection

Objective: This study sought to evaluate the clinical outcome after extended sentinel lymph node dissection (eSLND) and radical retropubic prostatectomy (RRP) in patients with clinically localized prostate cancer (PCa). Subjects and Methods: From August 2002 until February 2011, a total of 819 patients with clinically localized PCa, confirmed by biopsy, were treated with RRP plus eSLND. Biochemical recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) were assessed with Kaplan-Meier curves. Various histopathological parameters were analyzed by univariate and multivariate analysis. Results: The mean follow-up was 5.3 years. Lymph node (LN) metastases occurred in 140 patients. We removed an average of 10.9 LNs via eSLND from patients with pN1 PCa. Postoperatively, 121 pN1 patients temporarily received adjuvant androgen deprivation therapy. The mean survival periods for RFS, RFS after secondary treatment, CSS, and OS were 4.7, 7.0, 8.8, and 8.1 years, respectively. The cancer-specific death rate of the 140 pN1 patients was 13.6%. RFS, CSS, and OS were significantly correlated with pathological margin status, LN density, the total diameter of evident metastases, and membership in the subgroup ‘micrometastases only'. Conclusion: Despite the presence of LN metastases, patients with a low nodal tumor burden demonstrate a remarkable clinical outcome after undergoing eSLND and RRP, thus suggesting a potential curative therapeutic approach.

Nodal occult metastases in intermediate- and high-risk prostate cancer patients detected using serial section, immunohistochemistry, and real-time reverse transcriptase polymerase chain reaction: prospective evaluation with matched-pair analysis

BACKGROUND

The purpose of the study was to prospectively evaluate the incidence of nodal OCM assessed using SS, IHC, and RT-PCR in prostate cancer patients compared with the standard pathological evaluation (SPE), and to evaluate short-term oncological outcomes of patients with OCM.

PATIENTS AND METHODS

Fifty-four consecutive patients with intermediate- or high-risk prostate cancer treated with radical prostatectomy and extended pelvic LN dissection comprised the study population (StP). The central sections with the largest diameter of each LN of the StP and a matched-pair population (MpP) with identical characteristics as the StP were used to assess the improved detection rate of OCM. Pathological characteristics and biochemical recurrence-free survival were assessed according to the presence of macroscopic or OCM.

RESULTS

A total of 1064 LNs were processed in the 54 patients of the StP, with 11 (20.4%) patients with evident metastases at SPE and 7 with OCM (13.0% additional patients); the percentage of positive patients improved from 16.6% (18 of 108) of the MpP to 33.3% (18 of 54) of the StP (16% additional patients). The mean diameter of the 10 additional LNs with OCM found at SS only and of the 6 additional LNs found at IHC only was significantly lower than the mean diameter of the 28 metastases found at routine pathologic examination (RPE) (P < .0001). Patients with OCM showed risk of biochemical recurrence similar to patients with no LN metastases (P = .008).

CONCLUSION

SS, IHC, and RT-PCR can detect a not negligible percentage of OCM missed at RPE. Patients with OCM showed short-term oncological outcomes more similar to those with macroscopic metastases. Longer follow-up studies considering cancer-specific survival are needed.