The Clinical Significance of Perineural Invasion by Prostate Cancer on Needle Core Biopsy

Clinical significance of location of perineural cancer invasion detected on prostate needle core biopsy

The clinical impact of site-specific perineural invasion (PNI) in prostate cancer remains poorly understood. We compared radical prostatectomy findings and oncologic outcomes in 434 patients with single-site PNI on systematic sextant biopsy. PNI was present in the right apex (n = 62; 14%), right mid (n = 70; 16%), right base (n = 89; 21%), left apex (n = 64; 15%), left mid (n = 58; 13%), and left base (n = 91; 21%). There were no significant differences in biopsy or prostatectomy findings, when comparing apex vs. mid vs. base PNI. Univariate analysis revealed that apex-localized PNI was associated with a significantly higher risk of progression, compared with base (P = 0.037) or mid/base (P = 0.024) PNI. Multivariable analysis showed that apex-localized PNI was an independent risk factor for progression (hazard ratio 2.049, P = 0.002). Among biopsies demonstrating PNI at one sextant site, apex-localized PNI is independently associated with poorer prognosis, though not worse histopathologic features on prostatectomy, compared with mid or base PNI.

Gleason score 3+3=6 prostatic adenocarcinoma is not benign and the current debate is unhelpful to clinicians and patients

Prostate adenocarcinoma is a common malignancy associated with a significant morbidity and mortality. In both prostate biopsies and radical prostatectomy specimens Gleason scoring informs both treatment and outcome prediction. The current convention is that in needle biopsies, Gleason patterns 3, 4 and 5 are considered to be malignant. Despite this there is debate as to whether or not Gleason score (GS) 3+3=6 should be diagnosed as cancer due to potential over-treatment and the psychological impact on patients. It is apparent that GS 3+3=6 is indolent disease with a low risk of metastasis. However, it does have the histological features of malignancy and is capable of infiltrating the prostate gland, extraprostatic extension, and metastatic spread. Furthermore GS 3+3=6 carcinoma has immunohistochemical and molecular genetic features similar to those of higher grade prostatic carcinoma. If GS 3+3=6 tumour is considered benign, the question arises should a benign label be given to the Gleason pattern 3 component of tumour that includes Gleason patterns of higher grade? This would seem a logical step as GS 3+3=6 cancers and the pattern 3 component in cancers with multiple patterns are morphologically identical. If pattern 3 is considered to be benign, then Gleason scoring would be limited to 4+4=8, 4+5=9, 5+4=9 and 5+5=10 which is clearly inappropriate. The correct strategy to address potential over-treatment of patients with low-grade cancer is clinician and patient education, not the recalibration of Gleason grading to reclassify malignant tumours as benign.

Clinical impact of perineural invasion encircled completely vs. incompletely by prostate cancer on needle core biopsy

The clinical significance of the pattern or degree of perineural invasion (PNI) by prostate cancer remains largely unknown. We herein assessed radical prostatectomy findings and postoperative oncologic outcomes in 125 patients who had undergone systematic sextant prostate biopsy exhibiting only a single focus of PNI encircled completely (n = 57; 46 %) vs. incompletely (n = 68; 54 %) by cancer. Between these two cohorts, there were no significant differences in clinicopathological features on biopsy or prostatectomy, including tumor grade, stage, and length or volume, and surgical margin status, as well as the need for adjuvant therapy immediately after prostatectomy. Similarly, survival analysis demonstrated no significant difference in the risk of disease progression following prostatectomy in patients with encircled vs. non-encircled PNI on biopsy (P = 0.679). When the non-encircled cases were further divided into four groups [i.e. 1-25 % enclosed (n = 12; 18 %), 26-50 % enclosed (n = 18; 26 %), 51-75 % enclosed (n = 10; 15 %), 76-99 % enclosed (n = 28; 41 %)], the rates of progression-free survival were comparable among the five groups (P = 0.954). In prostate biopsy specimens exhibiting PNI at only one focus, the degree of nerve involvement thus appears to have little clinical impact. Accordingly, PNI detected on prostate biopsy may need to be similarly taken into consideration irrespective of the degree of nerve involvement.

Comprehensive analysis of predictive factors for upstaging in intraprostatic cancer after radical prostatectomy: Different patterns of spread exist in lesions at different locations

BACKGROUND

Accurate assessment of the clinical staging is crucial for determining the need for radical prostatectomy (RP) in prostate cancer (PCa). However, the current methods for PCa staging may yield incorrect results. This study aimed to comprehensively analyze independent predictors of postoperative upstaging of intraprostatic cancer.

METHODS

We conducted a retrospective analysis of data from intraprostatic cancer patients who underwent radical surgery between March 2019 and December 2022. Intraprostatic cancer was defined as a lesion confined to the prostate, excluding cases where multiparameter magnetic resonance imaging (mpMRI) showed the lesion in contact with the prostatic capsule. We assessed independent predictors of extraprostatic extension (EPE) and analyzed their association with positive surgical margin (PSM) status. In addition, based on the distance of the lesion from the capsule on mpMRI, we divided the patients into non-transition zone and transition zone groups for further analysis.

RESULTS

A total of 500 patients were included in our study. Logistic regression analysis revealed that biopsy Gleason grade group (GG) (odds ratio, OR: 1.370, 95% confidence interval, CI: 1.093-1.718) and perineural invasion (PNI) (OR: 2.746, 95% CI: 1.420-5.309) were predictive factors for postoperative EPE. Both biopsy GG and PNI were associated with lateral (GG: OR: 1.270, 95% CI: 1.074-1.501; PNI: OR: 2.733, 95% CI: 1.521-4.911) and basal (GG: OR: 1.491, 95% CI: 1.194-1.862; PNI: OR: 3.730, 95% CI: 1.929-7.214) PSM but not with apex PSM (GG: OR: 1.176, 95% CI: 0.989-1.399; PNI: OR: 1.204, 95% CI: 0.609-2.381) after RP. Finally, PNI was an independent predictor of EPE in the transition zone (OR: 11.235, 95% CI: 2.779-45.428) but not in the non-transition zone (OR: 1.942, 95% CI: 0.920-4.098).

CONCLUSION

PNI and higher GG may indicate upstaging of tumors in patients with intraprostatic carcinoma. These two factors are associated with PSM in locations other than the apex of the prostate. Importantly, cancer in the transition zone of the prostate is more likely to spread externally through nerve invasion than cancer in the non-transition zone.

Clinical Significance of Perineural Invasion by Prostate Cancer Detected on Needle Core Biopsy

OBJECTIVES

The clinical impact of the laterality of perineural invasion (PNI) by prostate cancer remains poorly understood. We herein compared radical prostatectomy (RP) findings and long-term oncologic outcomes in patients with prostate cancer with PNI in two prostate biopsy (PBx) sites.

METHODS

We retrospectively assessed 170 consecutive patients undergoing systematic sextant PBx where PNI had been detected in two of six PBx sites, followed by RP.

RESULTS

PNI occurred unilaterally in 140 (82.4%) cases and bilaterally in 30 (17.6%) cases. Compared with unilateral PNI, bilateral PNI was significantly associated with a higher number of cancer-positive sites and longer total tumor length on PBx. However, there were no significant differences in RP findings, including tumor grade/stage and tumor volume, between unilateral and bilateral PNI cohorts. Kaplan-Meier analysis revealed that patients with bilateral PNI had a significantly higher risk of disease progression after RP than those with unilateral PNI (P = .038). In multivariate analysis, bilateral PNI (vs unilateral PNI) showed significance for progression (hazard ratio, 2.281; P = .023).

CONCLUSIONS

In PBx specimens exhibiting PNI in two sextant sites, bilateral PNI was found to be associated with poorer prognosis as an independent predictor but not worse histopathologic features in RP specimens compared with unilateral PNI.

The Role of Perineural Invasion in Prostate Cancer and Its Prognostic Significance

Simple Summary

Prostate cancer is one of the most frequently diagnosed cancers in men worldwide. Perineural invasion (PNI), the movement of cancer cells along nerves, is a commonly observed approach to tumor spread and is important in both research and clinical practice of prostate cancer. However, despite many studies reporting on molecules and pathways involved in PNI, understanding its clinical relevance remains insufficient. In this review, we aim to summarize the current knowledge of mechanisms and prognostic significance of PNI in prostate cancer, which may provide new perspectives for future studies and improved treatment.

Abstract

Perineural invasion (PNI) is a common indication of tumor metastasis that can be detected in multiple malignancies, including prostate cancer. In the development of PNI, tumor cells closely interact with the nerve components in the tumor microenvironment and create the perineural niche, which provides a supportive surrounding for their survival and invasion and benefits the nerve cells. Various transcription factors, cytokines, chemokines, and their related signaling pathways have been reported to be important in the progress of PNI. Nevertheless, the current understanding of the molecular mechanism of PNI is still very limited. Clinically, PNI is commonly associated with adverse clinicopathological parameters and poor outcomes for prostate cancer patients. However, whether PNI could act as an independent prognostic predictor remains controversial among studies due to inconsistent research aim and endpoint, sample type, statistical methods, and, most importantly, the definition and inclusion criteria. In this review, we provide a summary and comparison of the prognostic significance of PNI in prostate cancer based on existing literature and propose that a more standardized description of PNI would be helpful for a better understanding of its clinical relevance.