Papillary Lesions of Breast- A Retrospective Analysis of Cytomorphological Features with Histopathology Concordance
Authors: Anila KR , Nayak Nileena , Sindhu Nair P , Rari P Mony , Jayasree K 
Published: April 2022

Introduction: Papillary lesions of the breast include a spectrum of entities ranging from benign papilloma to malignant papillary carcinoma. The overlapping morphological features in benign and malignant lesions make their accurate sub categorization difficult. Definitive surgical management decisions on papillary lesions of breast based on fine needle aspiration cytology report alone is a matter of concern. Aim: To evaluate the cytomorphological features of papillary lesions of breast and its concordance with histopathology. Materials and Methods: This retrospective study was conducted in Department of Pathology at Regional Cancer Centre, Thiruvananthapuram, Kerala, India (tertiary cancer centre) from January 2017 to June 2017. Total 28 cases diagnosed as papillary lesions/neoplasm on nipple discharge/fine needle aspiration cytology (FNAC) from January 2014 to December 2016 were reviewed and concordance with histopathology where ever available was analysed. Cytomorphological features that were analysed included cellularity, complex folded and branching epithelial sheets, stromal bare nuclei, cyst macrophages, single cells and atypia. Results: Total 28 cases of papillary lesions diagnosed by cytology were identified with mean age of 51 years. Out of 28, 22 cases had histopathology concordance. Most common diagnosis in cytology was papillary neoplasm, accurate categorization into benign or malignant could not be done in cytology in most of the cases. Most common diagnosis in histopathology was carcinoma, in-situ and invasive. Of total 22 cases,16 cases showed true papillae. Majority of the cytomorphological features assessed were statistically insignificant in differentiating benign and malignant lesions. Fifteen cases out of the total 22 cases turned out to be malignant in final histopathology. Out of the total 22 cases wherein histopathology correlation was available, cytology could give a conclusive diagnosis of malignancy in two cases and could give a suggestion of malignancy in seven cases. Out of these nine cases where cytology favoured malignancy, one case turned out to be benign in histopathology while the rest eight cases were malignant. In five cases cytology gave benign diagnosis, one of these turned out to be malignant in histopathology, rest four cases histopathological diagnosis was in concordance with cytology. In eight cases cytology gave an equivocal diagnosis of papillary neoplasm, where further categorisation into benign and malignant category was not possible. Out of these equivocal cases, six turned out to be malignant in histopathology and two were benign. Conclusion: Cytomorphological features of papillary lesions of the breast are not unique and are inadequate for consistent categorization into benign and malignant lesions. Excision biopsy with adequate sampling and immunostaining with myoepithelial markers and oestrogen and progesterone receptors (ER and PR) are essential for accurate categorization of papillary neoplasms of breast.