Low-Grade Ductal Carcinoma In Situ

• Published in: American journal of clinical pathology Vol. 153; no. 3; pp. 360 - 367
• Main Authors: Alghamdi, Sarah A, Krishnamurthy, Kritika, Garces Narvaez, Sofia A, Algashaamy, Khaled J, Aoun, Jessica, Reis, Isildinha M, Recine, Monica A, Jorda, Merce, Poppiti, Robert J, Gomez-Fernandez, Carmen R
• Format: Journal Article
• Language: English
• Published: US Oxford University Press 08.02.2020
• Subjects: Adult; Aged; Aged, 80 and over; Breast - pathology; Breast Neoplasms - diagnosis; Breast Neoplasms - pathology; Carcinoma, Intraductal, Noninfiltrating - diagnosis; Carcinoma, Intraductal, Noninfiltrating - pathology; Female; Humans; Male; Middle Aged; Neoplasm Grading; Observer Variation; Low-grade DCIS; Ductal carcinoma in situ; Interobserver reproducibility; Grading system
• ISSN: 0002-9173; 1943-7722
• DOI: 10.1093/ajcp/aqz179

Abstract Objectives We aimed to determine the interobserver reproducibility in diagnosing low-grade ductal carcinoma in situ (DCIS). We also aimed to compare the interobserver variability using a proposed two-tiered grading system as opposed to the current three-tiered system. Methods Three expert breast pathologists and one junior pathologist identified low-grade DCIS from a set of 300 DCIS slides. Months later, participants were asked to grade the 300 cases using the standard three-tiered system. Results Using the two-tiered system, interobserver agreement among breast pathologists was considered moderate (κ = 0.575). The agreement was similar (κ = 0.532) with the junior pathologist included. Using the three-tiered system, pathologists’ agreement was poor (κ = 0.235). Conclusions Pathologists’ reproducibility on diagnosing low-grade DCIS showed moderate agreement. Experience does not seem to influence reproducibility. Our proposed two-tiered system of low vs nonlow grade, where the intermediate grade is grouped in the nonlow category has shown improved concordance.