Prostate MRI prior to radical prostatectomy: effects on nerve sparing and pathological margin status

Comparing pentafecta outcomes between nerve sparing and non nerve sparing robot-assisted radical prostatectomy in a propensity score-matched study

Pentafecta (continence, potency, cancer control, free surgical margins, and no complications) is an important outcome of prostatectomy. Our objective was to assess the pentafecta achievement between nerve-spring and non-nerve-sparing robot-assisted radical prostatectomy (RARP) in a large single-center cohort. The study included 1674 patients treated with RARP between August 2009 and November 2022 to assess the clinical outcomes. Cox regression analyses were performed to evaluate the prognostic significance of RARP for pentafecta achievement, and 1:1 propensity score matching (PSM) was performed between the nerve-sparing and non-nerve-sparing to test the validity of the results. Pentafecta definition included continence, which was defined as the use of zero pads; potency, which was defined as the ability to achieve and maintain satisfactory erections or ones firm enough for sexual activity and sexual intercourse. The biochemical recurrence rate was defined as two consecutive PSA levels > 0.2 ng/mL after RARP; 90-day Clavien-Dindo complications ≤ 3a; and a negative surgical pathologic margin. The median follow-up period was 61.3 months (IQR 6-159 months). A multivariate Cox regression analysis demonstrated that pentafecta achievement was significantly associated with nerve-sparing (NS) approach (1188 patients) (OR 4.16; 95% CI 2.51-6.9), p < 0.001), unilateral nerve preservation (983 patients) (OR 3.83; 95% CI 2.31-6.37, p < 0.001) and bilateral nerve preservation (205 patients) (OR 7.43; 95% CI 4.14-13.36, p < 0.001). After propensity matching, pentafecta achievement rates in the NS (476 patients) and non-NS (476 patients) groups were 72 (15.1%) and 19 (4%), respectively. (p < 0.001). NS in RARP offers a superior advantage in pentafecta achievement compared with non-NS RARP. This validation study provides the pentafecta outcome after RARP associated with nerve-sparing in clinical practice.

Validation of user-friendly models predicting extracapsular extension in prostate cancer patients

Objective

There are many models to predict extracapsular extension (ECE) in patients with prostate cancer. We aimed to externally validate several models in a Japanese cohort.

Methods

We included patients treated with robotic-assisted radical prostatectomy for prostate cancer. The risk of ECE was calculated for each patient in several models (prostate side-specific and non-side-specific). Model performance was assessed by calculating the receiver operating curve and the area under the curve (AUC), calibration plots, and decision curve analyses.

Results

We identified ECE in 117 (32.9%) of the 356 prostate lobes included. Patients with ECE had a statistically significant higher prostate-specific antigen level, percentage of positive digital rectal examination, percentage of hypoechoic nodes, percentage of magnetic resonance imaging nodes or ECE suggestion, percentage of biopsy positive cores, International Society of Urological Pathology grade group, and percentage of core involvement. Among the side-specific models, the Soeterik, Patel, Sayyid, Martini, and Steuber models presented AUC of 0.81, 0.78, 0.77, 0.75, and 0.73, respectively. Among the non-side-specific models, the memorial Sloan Kettering Cancer Center web calculator, the Roach formula, the Partin tables of 2016, 2013, and 2007 presented AUC of 0.74, 0.72, 0.64, 0.61, and 0.60, respectively. However, the 95% confidence interval for most of these models overlapped. The side-specific models presented adequate calibration. In the decision curve analyses, most models showed net benefit, but it overlapped among them.

Conclusion

Models predicting ECE were externally validated in Japanese men. The side-specific models predicted better than the non-side-specific models. The Soeterik and Patel models were the most accurate performing models.

Extraprostatic extension in prostate cancer: primer for radiologists

The presence of extraprostatic extension (EPE) on multiparametric MRI (mpMRI) is an important factor in determining the management of prostate cancer. EPE is an established risk factor for biochemical recurrence of prostate cancer after radical prostatectomy (RP) and patients with EPE may be considered for wider resection margins, non-nerve-sparing surgery, adjuvant radiation therapy (RT), or androgen deprivation therapy (ADT). Several statistical nomograms and scoring systems have been developed to predict pathological stage at time of RP but with varying accuracies. Using the current PI-RADS v2 mpMRI staging guidelines results in high specificity but lacks in sensitivity. These findings reveal the need for more standardization and further refinement of existing MRI protocols and prostate cancer prediction tools. Current studies have looked into indirect additional imaging criteria such as index tumor volume, length of capsular contact, and apparent diffusion coefficient. Measuring for these features can improve the robustness of mpMRI in staging prostate cancer, as they have been shown to be independent predictors of EPE. MRI/ultrasound fusion-guided targeted biopsy can detect EPE not found on standard biopsy. Collectively, these measurements and imaging techniques can augment the detection of EPE and subsequent risk stratification.

Diagnostic ability of Ga-68 PSMA PET to detect dominant and non-dominant tumors, upgrading and adverse pathology in patients with PIRADS 4-5 index lesions undergoing radical prostatectomy

BACKGROUND

To evaluate the additive role of Ga-68 PSMA PET as a primary staging tool in patients bearing prostate cancer in single PIRADS 4 or 5 index lesions.

METHODS

Eighty-one biopsy-naive patients with preoperative mpMRI and Ga-68 PSMA PET who underwent radical prostatectomy (RP) were evaluated retrospectively. Forty-nine patients had PIRADS 4 and 32 had PIRADS 5 index lesions. The localization, grade, and volumetric properties of dominant (DT) and non-dominant tumors (NDT) in RP were compared to the index lesions of mpMRI and Ga-68 PSMA PET.

RESULTS

The median age and PSA level were 62 (IQR; 59-69) years and 7 (IQR; 2-8) ng/ml, respectively. Ga-68 PSMA PET detected DTs in 100% of the patients including 13 patients in whom mpMR failed. In 45 patients an NDT was reported in RP. Ga-68 PSMA PET accurately detected NDT in 24 of 45 (53.3%) patients. Six patients (12.2%) in PIRADS 4 and 8 (25%) in PIRADS 5 group showed upgrading. In PIRADS 4, Ga-68 PSMA PET localized DT in all patients with upgraded tumors whereas mpMRI missed exact location in 2 of 6 (33.3%). In PIRADS 5 both mpMRI and Ga-68 PSMA PET accurately located all DTs. Overall detection rates of extracapsular extension (ECE) and seminal vesicle invasion (SVI) by mpMRI were 51.1% and 53.8%, respectively. Ga-68 PSMA PET detected ECE and SVI in 27.9% and 30.7%, respectively. When mpMRI and Ga-68 PSMA PET were used in combination detection rates of ECE and SVI increased to 65.1 and 61.5%. Ga-68 PSMA PET-detected six of ten patients with positive lymph nodes whereas mpMRI could not identify any.

CONCLUSIONS

Ga-68 PSMA PET has a better diagnostic accuracy in detecting DT, NDT, upgrading, adverse pathology in patients with PIRADS 4 index lesions. However, mpMRI better predicted ECE and SVI than Ga-68 PSMA PET.

The Use of MRI and PET Imaging Studies for Prostate Cancer Management: Brief Update, Clinical Recommendations, and Technological Limitations

Multi-parametric magnetic resonance imaging (mpMRI) and positron emission tomography (PET) using prostate-specific membrane antigen (PSMA) targeting ligands have been adopted as a new standard of imaging modality in the management of prostate cancer (PCa). Technological advances with hybrid and advanced computer-assisted technologies such as MR/PET, MR/US, multi-parametric US, and robotic biopsy systems, have resulted in improved diagnosis and staging of patients in various stages of PCa with changes in treatment that may be considered “personalized”. Whilst newer clinical trials incorporate these novel imaging modalities into study protocols and as long-term data matures, patients should be made aware of the potential benefits and harm related to these technologies. Published literature needs to report longer-term treatment efficacy, health economic outcomes, and adverse effects. False positives and negatives of these imaging modalities have the potential to cause harm and the limitations of these technologies should be appreciated. The role of a multi-disciplinary team (MDT) and a shared-decision-making model are important to ensure that all aspects of the novel imaging modalities are considered.

Clinical utility of MRI in the decision-making process before radical prostatectomy: Systematic review and meta-analysis

Context

Magnetic resonance imaging (MRI) is currently the most accurate imaging modality to assess local prostate cancer stage. Despite a growing body of evidence, incorporation of MRI images into decision-making process concerning surgical template of radical prostatectomy, is complex and still poorly understood.

Objective

We sought to determine the value of MRI in preoperative planning before radical prostatectomy.

Materials and methods

Systematic search through electronic PubMed, EMBASE, and Cochrane databases from 2000 up to April 2018 was performed. Only studies that used preoperative MRI in decision-making process regarding extension of resection in patients with prostate cancer, in whom radical prostatectomy was an initial form of treatment were included into analysis. Their quality was scored by Risk Of Bias In Non-Randomized Studies of Interventions system. Meta-analysis was performed to calculate the weighted summary proportion under the fixed or random effects model as appropriate and pooled effects were depicted on forest plots.

Results

The results showed that the preoperative MRI led to the modification of initial surgical template in one third of cases (35%). This occurred increasingly with the rising prostate cancer-risk category: 28%, 33%, 52% in low-, intermediate- and high-risk group, respectively. Modification of neurovascular bundle-sparing surgery based on MRI appeared to have no impact on the positive surgical margin rate. The decision based on MRI was correct on average in 77% of cases and differed across prostate cancer-risk categories: 63%, 75% and 91% in low-, intermediate- and high-risk group, accordingly.

Conclusions

In summary, MRI has a considerable impact on the decision-making process regarding the extent of resection during radical prostatectomy. Adaptation of MRI images by operating surgeons has at worst no significant impact on surgical margin status, however its ability to decrease the positive surgical margin rates remains unconfirmed.