Performance characteristics of mucinous (colloid) XXXX in fine-needle aspirates: observations from the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytopathology.

@entity1 @entity0 @entity39 @entity75 @entity189 @entity3923 @entity1557 @entity2883 @entity6377
CONTEXT: @entity0 has characteristic cytologic features, but few studies exist that analyze the reproducibility of this diagnosis. OBJECTIVE: To analyze @entity1 ' diagnosis of @entity189 in breast fine-needle aspiration (FNA) slides distributed in an educational interlaboratory peer comparison program. DESIGN: @entity1 responses for FNA slides with a reference diagnosis of @entity189 , distributed between 2001-2008 in the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytopathology, were evaluated for concordance with the general category and reference diagnosis of @entity189 . RESULTS: Of 8061 responses, 6353 (78.8%) were categorized as malignant; 775 (9.6%) as suspicious; and 933 (11.6%) as negative. The most frequent incorrect responses for the benign category included @entity1557 (51.7%), nonspecified @entity75 (12%), @entity3923 (7.8%), and fat @entity39 / @entity2883 / @entity6377 (6.9%). Conventional Papanicolaou-stained preparations were reviewed for 58.7% (4732) of responses; of these, 39.4% (3177) were from modified Giemsa-stained smears and 1.9% (152) from ThinPrep slides. Papanicolaou-stained conventional smears had the lowest concordance (86.5%) when compared to modified Giemsa-stained smears (91.2%) and ThinPrep challenges (92.1%) (P < .001). @entity1 specifically diagnosed @entity189 37.3% of the time, and modified Giemsa-stained challenges performed best (43.1%, P < .001). There was no significant difference between cytotechnologists' and pathologists' responses (87.9% versus 88.2%; P = .69). CONCLUSIONS: @entity189 in FNA was not accurately identified in a glass slide interlaboratory comparison program. We observed better performance with modified Giemsa-stained and ThinPrep slides than with Papanicolaou-stained preparations. The most common response for the benign category of @entity189 was @entity1557 . Increased awareness of the cytologic features of @entity189 may improve accuracy in breast FNA.
