Atypical Ductal Hyperplasia at the Margin of Lumpectomy Performed for Early Stage Breast Cancer: Is there Enough Evidence to Formulate Guidelines?

Table 1

Interobserver variability among pathologists in cases of borderline ductal proliferative lesions.

Investigator	no. of pathologists/no. of slides reviewed	Concordance rates (%)
	6/24	5/5 agreed 0%
Rosai [21]		4/5 agreed 20%
		3/5 agreed 50%
	5/10	6/6 agreed 58%
Schnitt et al. [22]*		5/6 agreed 71%
		4/6 agreed 92%
	9/81	9/9 agreed 32%
Jain et al. [23]		8/9 agreed 52%
		7/9 agreed 63%

∗Standardized criteria and formal education differentiating proliferative lesions provided to pathologist prior to reviewing slides.