Inherent Grading Characteristics of Individual Pathologists Contribute to Clinically and Prognostically Relevant Interobserver Discordance Concerning Broders' Grading of Penile Squamous Cell Carcinomas

Abstract

Introduction: We assessed the reproducibility and prognostic impact of the Broders' grading system (BGS) in a cohort of 147 patients with surgically treated penile squamous cell carcinomas. Materials and Methods: Conventionally stained histology slides were graded according to the BGS in two rounds by two study pathologists. Reproducibility was assessed using ĸ statistics. Multivariable analyses were calculated to predict cancer-specific survival (CSS). The ‘mean grade' per pathologist per round was calculated by allocating grade points to each study case (G1-G4: 1-4 points) and dividing the sum of all grade points by the number of cases examined. Results: The BGS showed substantial interobserver variation (59-87% with ĸ = 0.38-0.69) but almost perfect intraobserver reproducibility (91% with ĸ = 0.86 and 96% with ĸ = 0.94, respectively). The ‘mean grade' per pathologist remained nearly constant in both rounds of examination (differences ≤0.05 grade points) but differed between the two pathologists (up to 0.4 grade points). In multivariable analyses, the prognostic impact of the BGS in terms of CSS was strongly pathologist-dependent. Conclusions: Clinically and prognostically relevant interobserver discordance concerning the BGS seems, at least in part, to be attributable to inherent ‘aggressive' versus ‘reserved' grading characteristics of individual pathologists.

The role of histologic subtype, p16INK4a expression, and presence of human papillomavirus DNA in penile squamous cell carcinoma

“…This is in line with some previous studies that failed to confirm a proposed association between histopathologic grade and lymph node metastasis or overall survival in pSCC, while it has to be stated as a clear limitation of our study that follow-up data was only obtainable for 35 patients (60.3%) [ 38 - 40 ]. Considering the substantial interobserver variability that has been described for histopathologic grading in pSCC (between 59-87% with ĸ = 0.38-0.69 [ 41 ]), we think that the current histopathologic grading is of limited value due to an obvious lack of prognostic relevance; this conclusion is also supported by other authors [ 42 ]. For the presence of HR-HPV we observed a trend towards better prognosis that failed to reach statistical significance; further investigations in larger cohorts might therefor be indicated.…”

Novel prognostic histopathological grading system in oral squamous cell carcinoma based on tumour budding and cell nest size shows high interobserver and intraobserver concordance

“…Interobserver agreement of the HR model was good with κ =0.84 37. Data on interobserver and intraobserver reliability of the Broder’s/WHO grading system is available for penile SCC by Naumann et al 54 and Gunia et al 55. In this entity, essentially the same grading criteria as in OSCC are used.…”

10-Year experience regarding the reliability and morbidity of radio guided lymph node biopsy in penile cancer patients and the associated radiation exposure of medical staff in this procedure

“…However, the reliability of histopathological tumour grading based solely on rapid frozen section is unclear and has not been described in literature yet. Even paraffin-embedded specimens show a high degree of inter-observer variability among pathologists with respect to tumour staging and tissue differentiation [ 17 , 18 ]. Taking these facts into account, we accepted a possible over diagnosis/-treatment in a very low number of patients with T1G1-tumours by SLNB.…”