Percent Gleason pattern 4 in stratifying the prognosis of patients with intermediate-risk prostate cancer

Abstract

The Gleason score remains the most reliable prognosticator in men with prostate cancer. One of the recent important modifications in the Gleason grading system recommended from the International Society of Urological Pathology consensus conference is recording the percentage of Gleason pattern 4 in the pathology reports of prostate needle biopsy and radical prostatectomy cases with Gleason score 7 prostatic adenocarcinoma. Limited data have indeed suggested that the percent Gleason pattern 4 contributes to stratifying the prognosis of patients who undergo radical prostatectomy. An additional obvious benefit of reporting percent pattern 4 includes providing critical information for treatment decisions. This review summarizes and discusses available studies assessing the utility of the percentage of Gleason pattern 4 in the management of prostate cancer patients.

Defining clinically significant prostate cancer on the basis of pathological findings

“…As the percentage of Gleason pattern 4 is currently being reported in the diagnosis, a number of research studies have been carried out to establish a category of patients with a ‘favourable’ prognosis who would benefit from AS. So far, these studies have found that patients with ‘favourable’ Gleason 3 + 4 = 7 (GrG2) still have a higher risk of Gleason grade 4 + 3 = 7 (GrG), EPE, and seminal vesicle invasion at RP, and a higher risk of BCR, than low‐risk men undergoing RP .…”

“…On analysis of RP specimens of patients that would have met the criteria for AS except for a minor component of Gleason pattern 4 at needle biopsy, the rate of adverse findings was significantly higher in this group (21.6%) than in controls, the most common being Gleason grade 4 + 3 = 7 or higher (GrG ≥ 3). 35 As the percentage of Gleason pattern 4 is currently being reported in the diagnosis, 32,36,37 a number of research studies have been carried out to establish a category of patients with a 'favourable' prognosis who would benefit from AS. So far, these studies have found that patients with 'favourable' Gleason 3 + 4 = 7 (GrG2) still have a higher risk of Gleason grade 4 + 3 = 7 (GrG), EPE, and seminal vesicle invasion at RP, and a higher risk of BCR, than low-risk men undergoing RP.…”

“…48,49 The first criteria for AS, which are known as the Epstein criteria, were adopted as the 'very-low-risk' criteria in the NCCN guidelines, and correspond to one or two cores with cancer Gleason score 3 + 3 = 6 (GrG1), no core with >50% of cancer, and a PSA density of <0.15 ng/ml per cm 3 . 4 This criterion was developed on the basis of a study that reviewed the clinical and pathological characteristics of men who underwent RP for T1c More EPE, 26 higher risk of BCR, 20 higher risk of undersampled high-grade tumours 29 Tumour grade GrG1 4 'Favourable' GrG2 37,38 Higher risk of GrG3, EPE, SV invasion, and BCR 37,38 EPE No EPE 4 Focal EPE or non-focal EPE [41][42][43][44][45] Higher risk of BCR and local recurrence 41 BCR, Biochemical recurrence; EPE, Extraprostatic extension; GrG1, Gleason 6 (Grade Group 1); GrG2, Gleason 3 + 4 = 7 (Grade Group 2); GrG3, Gleason 4 + 3 = 7 (Grade Group 3); SV, seminal vesicle.…”

A critical evaluation of visual proportion of Gleason 4 and maximum cancer core length quantified by histopathologists

“…In our study, the visual estimation of %G4 differed from the digital one; accurate measurement of the G4 burden has been shown to help risk-stratify patients 9 , 17 . In a study by de Souza et al .…”

“…Despite these differences, the Bland-Altman analysis showed good concordance between the two measurements; thus, the accuracy of the MCCL is not compromised when a digital tool is used. In our study, the visual estimation of %G4 differed from the digital one; accurate measurement of the G4 burden has been shown to help risk-stratify patients 9,17 . In a study by de Souza et al, 20% of Gleason 3 + 4 tumours had more extensive G4 disease than the first quartile of 4 + tumours in radical prostatectomy specimens 18 .…”