"1. Alterations of enlarged lobular units; 1.1 apocrine cyst versus columnar cell lesion without atypia; 1.2 columnar cell lesion with atypia versus columnar cell lesion without atypia; 1.3 secretory change versus columnar cell lesion with atypia ; 1.4 hypersecretory change versus ductal carcinoma in situ ; 1.5 papillary apocrine change versus apocrine ductal carcinoma in situ; 2. Epithelial proliferative lesions ; 2.1 Usual hyperplasia versus atypical ductal hyperplasia; 2.2 Gynecomastoid ñtype hyperplasia versus micropapillary atypical ductal hyperplasia or micropapillary ductal carcinoma in situ; 2.3 Usual hyperplasia (solid pattern) versus atypical ductal hyperplasia; 2.1 Prominent myoepithelial cells versus atypical ductal hyperplasia; 2.2 Papilloma involved by florid hyperplasia versus atypical ductal hyperplasia ; 2.3 Atypical ductal hyperplasia versus low grade ductal carcinoma in situ; 2.4 Cribriform atypical ductal hyperplasia versus collagenous spherulosis; 2.5 Atypical ductal hyperplasia versus atypical lobular hyperplasia; 2.6 Florid hyperplasia versus intermediate or high grade ductal carcinoma in situ; 2.7 Mucocele-like lesion with atypical ductal hyperplasia versus mucocele-like lesion without atypia; 2.8 Papillary apocrine change versus apocrine atypical ductal hyperplasia or apocrine ductal carcinoma in situ ; ; 3 Ductal carcinoma in situ; 3.1 Ductal carcinoma in situ versus atypical lobular hyperplasia in a papilloma; 3.2 Ductal carcinoma in situ versus microinvasive carcinoma; 3.3 Entrapped epithelial elements post biopsy of ductal carcinoma in situ in papilloma versus invasion; 3.4 Spindle cell pattern ductal carcinoma in situ versus florid hyperplasia; 3.5 Encysted noninvasive papillary carcinoma versus atypical ductal hyperplasia in a papilloma; 3.6 PagetÃs disease versus toker cells; 3.7 Ductal carcinoma in situ versus lobular carcinoma in situ; 3.8 Secretory ductal carcinoma in situ versus usual hyperplasia with clear cells; 3.9 Pagetoid pattern ductal carcinoma in situ versus ALH; 3.10 Radiation change versus ductal carcinoma in situ; ; 4 Lobular carcinoma in situ; 4.1 Classic lobular carcinoma in situ versus variant lobular carcinoma in situ; 4.2 Classic lobular carcinoma in situ versus atypical lobular hyperplasia; 4.3 Usual hyperplasia with prominent myoepithelial cells versus lobular neoplasia; 4.4 Ductal involvement by cells of atypical lobular hyperplasia versus low grade ductal carcinoma in situ; ; 5 Sclerosing and adenotic lesions; 5.1 Nodular sclerosing adenosis versus papilloma; 5.2 Papilloma versus adenomyoepithelioma; 5.3 Radial scar versus pure tubular carcinoma; 5.4 Sclerosed adenotic papilloma versus tubular carcinoma; 5.5 Sclerosing adenosis versus microglandular adenosis; 5.6 Nonspecific perilobular or periductal chronic inflammation versus sclerosing lymphocytic lobulitis; ; 6 Fibroepithelial lesions; 6.1 Fibroadenoma versus cellular fibroadenoma; 6.2 Fibroadenoma versus benign phyllodes tumor; 6.3 Benign phyllodes tumor versus borderline phyllodes tumor; 6.4 Borderline phyllodes tumor versus malignant phyllodes tumor; 6.5 Malignant phyllodes tumor versus pure sarcoma ; ; 7 Stromal lesions; 7.1 Myofibroblastoma versus fibromatosis; 7.2 Epithelioid myofibroblastoma versus pure invasive lobular carcinoma; 7.3 Myofibroblastoma versus low grade spindle cell metaplastic carcinoma; 7.4 Spindle cell metaplastic carcinoma versus post biopsy spindle cell nodule; 7.5 Fibromatosis versus scar; ; 8 Special type carcinomas; 8.1 Invasive pure lobular carcinoma versus lobular variant carcinomas versus no special type carcinoma with lobular features ; 8.2 Pure nvasive cribriform carcinoma versus cribriform ductal carcinoma in situ ; 8.3 Invasive pure tubular carcinoma versus no special type carcinoma with tubular features ; 8.4 Pure mucinous carcinoma versus mucocele-like lesion; 8.5 Pure medullary carcinoma versus no special type carcinoma with medullary features; 8.6 Secretory carcinoma versus no special type carcinoma; 8.7 Adenoid cystic carcinoma versus no special type carcinoma with myoepithelial phenotype or ductal carcinoma in situ ; 8.8 Low grade spindle cell metaplastic carcinoma versus fibromatosis; 8.9 Adenosquamous carcinoma versus squamous metaplasia; 8.10 Histiocytes versus histiocytoid variant of invasive lobular carcinoma; 8.11 Atypical lobular hyperplasia involving sclerosing adenosis versus invasive lobular carcinoma; ; 9 Invasive carcinomas of no special type, special considerations; 9.1 Lymphovascular invasion versus retraction artifact; 9.2 Invasive micropapillary features versus retraction artifact; 9.3 No special type tumors with immunohistochemical evidence of neuroendocrine differentiation versus small cell carcinoma; 9.4 High grade carcinoma versus lymphoma; ; 10 Sentinel lymph nodes ; 10.1 Benign transport versus isolated tumor cell clusters; 10.2 Isolated tumor cells versus micrometastasis; 10.3 Micrometastasis versus capsular lymphatic involvement; 10.4 Micrometastasis versus benign glandular inclusion; ; 11 Vascular lesions of the breast; 11.1 Perilobular capillary hemangioma; 11.2 Atypical vascular lesion ; 11.3 Low grade angiosarcoma ; 11.4 High grade angiosarcoma; 11.5 Epithelioid angiosarcoma; ; "