The significance of the diagnosis of atypia in breast fine‐needle aspiration

The diagnosis of atypia in breast fine‐needle aspiration (FNA) continues to be an area of debate in cytology practice. The aim of this study was to assess the clinical significance of this term and to evaluate potential morphological criteria, which would determine the patient's outcome. A computer‐based search was carried out to retrieve breast FNAs performed between 1990 and 2000 that were diagnosed as atypical. Cases followed by surgical resection were reexamined for the presence of morphological features potentially differentiating benign and malignant lesions. Out of 1,568 breast FNAs, there were 64 cases (4%) with a diagnosis of atypia. Thirty‐eight cases had surgical follow‐up material that revealed malignancy in 14 cases (37%) and benign lesions in 24 cases (63%). The benign diagnostic categories included fibrocystic change (12/24), fibroadenoma (3/24), tubular adenoma (2/24), and nonspecific findings (7/24). The malignant diagnoses included ductal carcinoma (9/14), lobular carcinoma (3/14), ductal carcinoma in situ (DCIS; 1/14), and tubular carcinoma (1/14). The evaluation of cytological criteria used to differentiate benign from malignant lesions (i.e., cellularity, loss of cohesion, myoepithelial cells, nuclear enlargement, nuclear overlap, prominent nucleoli) revealed significant overlap between benign and malignant cases, particularly in cases of fibroadenoma, tubular adenoma, and proliferative breast disease. The surgical follow‐up of four hypocellular cases revealed lobular carcinoma in two cases and ductal carcinoma in the remaining two cases. Our study confirmed that the diagnosis of atypia is clinically significant because it is associated with a high probability of malignancy. No morphological criterion is able to reliably differentiate benign and malignant lesions in cases diagnosed with atypia. Diagnosis of atypia is particularly significant in hypocellular cases. We recommended that breast FNAs with a diagnosis of atypia be evaluated further histologically. Diagn. Cytopathol. 2004;31:285–288. © 2004 Wiley‐Liss, Inc.

[1]  C. Elston,et al.  An audit of ‘equivocal’ (C3) and ‘suspicious’ (C4) categories in fine needle aspiration cytology of the breast , 2001, Cytopathology : official journal of the British Society for Clinical Cytology.

[2]  S. Tabbara,et al.  The spectrum of cytologic features in nonproliferative breast lesions , 2001, Cancer.

[3]  M. Mayo,et al.  Short-term breast cancer prediction by random periareolar fine-needle aspiration cytology and the Gail risk model. , 2000, Journal of the National Cancer Institute.

[4]  S. Tabbara,et al.  Cytologic features of proliferative breast disease , 2000, Cancer.

[5]  N. Sneige,et al.  Changing trends in breast fine‐needle aspiration: Results of the Papanicolaou society of cytopathology survey , 2000, Diagnostic cytopathology.

[6]  L. Howell.  Equivocal diagnoses in breast aspiration biopsy cytology: Sources of uncertainty and the role of “atypical/indeterminate” terminology , 1999, Diagnostic cytopathology.

[7]  S. Masood.  Diagnostic terminology in fine‐needle aspiration biopsy of the breast , 1999, Cancer.

[8]  B. Fornage,et al.  Ultrasound‐guided fine‐needle aspiration (FNA) of nonpalpable breast lesions , 1999, Cancer.

[9]  W J Frable,et al.  Interobserver variability in the classification of proliferative breast lesions by fine‐needle aspiration: Results of the Papanicolaou Society of Cytopathology study , 1998, Diagnostic cytopathology.

[10]  B. Fornage,et al.  In search of specimen adequacy in fine-needle aspirates of nonpalpable breast lesions. , 1997, American journal of clinical pathology.

[11]  W. Dupont,et al.  Probabilistic approach to the reporting of fine‐needle aspiration cytology of the breast , 1997, Cancer.

[12]  M. Sidawy,et al.  Can nonproliferative breast disease and proliferative breast disease without atypia be Distinguished by fine‐needle aspiration cytology? , 1997, Cancer.

[13]  The Uniform Approach to Breast Fine Needle Aspiration Biopsy: A Synopsis , 1996, Acta cytologica.

[14]  I. Ramzy,et al.  Analysis of false results in a series of 835 fine needle aspirates of breast lesions. , 1995, Acta cytologica.

[15]  N. Sneige,et al.  A plea for uniform terminology and reporting of breast fine needle aspirates. M.D. Anderson Cancer Center proposal. , 1994, Acta cytologica.

[16]  N. Al‐Kaisi.  The spectrum of the "gray zone" in breast cytology. A review of 186 cases of atypical and suspicious cytology. , 1994, Acta cytologica.

[17]  N. Sneige,et al.  Fine-needle aspiration cytology of ductal hyperplasia with and without atypia and ductal carcinoma in situ. , 1994, Human pathology.

[18]  M. Stanley,et al.  Atypia in breast fine-needle aspiration smears correlates poorly with the presence of a prognostically significant proliferative lesion of ductal epithelium. , 1993, Human pathology.

[19]  N. Sneige.  Fine‐needle aspiration of the breast: A review of 1,995 cases with emphasis on diagnostic pitfalls , 1993, Diagnostic cytopathology.

[20]  S. Ciatto,et al.  Positive predictive value of fine needle aspiration cytology of breast lesions. , 1989, Acta cytologica.

[21]  J. Peterse,et al.  Atypia in fine-needle aspiration cytology of the breast: a histologic follow-up study of 301 cases. , 1989, Seminars in diagnostic pathology.

[22]  A. Howat.  Uniform approach to breast fine needle aspiration biopsy. , 1998, Acta cytologica.

[23]  M. Bibbo,et al.  The uniform approach to breast fine-needle aspiration biopsy. National Cancer Institute Fine-Needle Aspiration of Breast Workshop Subcommittees. , 1997, Diagnostic cytopathology.

[24]  The uniform approach to breast fine‐needle aspiration biopsy , 1997, American journal of surgery.

[25]  A. Dawson,et al.  Atypia in fine needle aspiration cytology of nonpalpable and palpable mammographically detected breast lesions. , 1994, Acta cytologica.