Diagnostic Pitfalls in Papillary Lesions of the Breast: Experience from a Single Tertiary Care Center.

Introduction: Papillary neoplasms are a group of lesions that are characterized by presence of papillae supported by fibrovascular cores lined by epithelial cells with or without myoepithelial cell layer. These neoplasms may be benign, atypical or malignant.

Aims: This study was conducted to analyse the clinicopathological characteristics of papillary lesions of the breast.

Materials And Methods: A retrospective and prospective analysis of 34 cases of papillary lesions received over a period of 7 years from 2009 to 2015 was done. The patient's clinical details were collected from medical archives and the histopathological findings were reviewed. The lesions were classified into benign, atypical and malignant categories.

Results: During the study period, there were 34 cases of papillary lesions of breast. The mean age was 58 years. The central quadrant was the most common location (66.6%). The most common presenting complaint was lump (76.5% cases). Papillary lesions presented more commonly as solitary lump (82.4%) rather than multifocal disease. Benign papillary lesions were more common than the atypical and malignant lesions. The most common papillary lesion accounting for 43% of the cases was intraductal papilloma. Malignant lesions accounted for 41.2% cases with intraductal papillary carcinoma and invasive papillary carcinoma constituting 14.7% cases each.

Conclusion: Diagnosis of papillary carcinoma is challenging and its classification includes different entities that have specific diagnostic criteria. Due to their heterozygosity in morphology with benign, atypical and malignant subtypes, morphological features such as type of fibrovascular core and continuity of myoepithelial layer along with immunohistochemical stains for myoepithelial cells should be considered for proper and accurate diagnosis.