The predictive ability of a CK5/p63/CK8/18 antibody cocktail in stratifying breast papillary lesions on needle biopsy: an algorithmic approach works best.
OBJECTIVE
Immunohistochemical markers have been shown to assist in the stratification of breast papillary lesions. We evaluated the ability of different cytokeratin (CK) and p63 expression profiles on needle biopsy specimens to predict excision diagnoses.


METHODS
A CK5/p63/CK8/18 antibody cocktail was applied to 58 needle biopsy specimens (32 papillomas, 7 atypical papillomas, 19 papillary carcinomas on excision).


RESULTS
p63 expression was greater in papillomas than in atypical papillomas (P = .044) and papillary carcinomas (P< .0001). Papillary carcinomas and atypical papillomas showed greater CK8/18 expression (and conversely less CK5 expression) than did papillomas (P < .0001). Negative or focal p63 expression was 96% sensitive for diagnosing any atypical lesion (atypical papilloma or papillary carcinoma) on excision, whereas CK8/18 predominant expression (≥80% cells) was 100% sensitive. In contrast, the sensitivity of the original diagnosis was only 81%. The greatest accuracy for the diagnosis of atypical papillary lesions (95%) was achieved when both p63 and cytokeratins were used in combination in an algorithmic fashion. This method also correctly identified all cases that had papillary carcinoma (100% sensitivity) on excision.


CONCLUSIONS
Although a single stain or combination cannot independently stratify papillary lesions, a CK5/p63/CK8/18 antibody cocktail is a useful adjunct to morphology for evaluating breast papillary lesions in needle biopsy specimens.
Department of Pathology, Microbiology and Immunology, Vanderbilt University, 1161 21st Ave S, MCN C-3321, Nashville, TN 37232-2561; emily.s.reisenbichler@vanderbilt.edu.
Emily S
ES
Reisenbichler
Amy L
AL
Adams
Omar
O
Hameed
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor / Q000032:analysis*; D001707:Biopsy, Needle; D001943:Breast Neoplasms / Q000145:classification / Q000175:diagnosis*; D002291:Carcinoma, Papillary / Q000145:classification / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053538:Keratin-18 / Q000032:analysis / Q000096:biosynthesis; D053555:Keratin-5 / Q000032:analysis / Q000096:biosynthesis; D053533:Keratin-8 / Q000032:analysis / Q000096:biosynthesis; D008565:Membrane Proteins / Q000032:analysis / Q000096:biosynthesis; D008875:Middle Aged; D010212:Papilloma / Q000145:classification / Q000175:diagnosis; D011237:Predictive Value of Tests
D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; C081876:CKAP4 protein, human; D053538:Keratin-18; D053555:Keratin-5; D053533:Keratin-8; D008565:Membrane Proteins
Breast; Cytokeratin 5; Cytokeratin 8/18; Needle core biopsy; Papillary lesions; p63