Pathologists disagree with one another’s interpretations about 8 percent of the time when diagnosing a single breast biopsy slide, according to a study published March 22 in the Annals of Internal Medicine. The present study applied previous discrepancy findings from the Breast Pathology Study (B-Path) to patient populations. Discordance between individual pathologists and a reference consensus diagnosis was more likely in cases of ductal carcinoma in situ (DCIS) or atypia, with higher levels of overinterpretation of disease risk. The authors say that this “diagnostic grey zone” needs to be considered in clinical management decisions. Histopathological diagnosis remains the gold standard of breast cancer diagnosis, despite concerns about the variability in specimen interpretations in clinical practice. B-Path previously found that one in four breast biopsy results were discordant with expert reference consensus diagnosis. But, experts note the study included higher proportions of cases of DCIS and atypia than typically seen in clinical practice. However, the study did not assess population impact. The present study estimated the effect of interpretation variation from the perspective of U.S. woman having a biopsy. The researchers calculated predictive values using Bayes’ theorem, combining results from B-Path with published data of the population-based prevalence of breast pathology […]