Simultaneous Occurrence of Ductal Carcinoma In Situ within Juvenile Fibroadenoma in Both Breasts: A Brief Case Report

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Juvenile fibroadenoma is a rare variant of fibroadenoma accounting for 4% of all fibroadenomas and characterized by rapid enlargement of single or multiple, painless, discrete masses, usually occurring in subjects aged <20 years. 1 The incidence of carcinoma within fibroadenoma is between 0.0125% and 0.3% in the general population, 2,3 and only 0.9% of such carcinomas occur as synchronous bilateral carcinomas arising in bilateral fi-broadenomas. 3 Carcinoma arising in fibroadenoma was first described by Cheatle and Cutler. 4 Since then, more than 200 cases have been reported, with the largest series comprising 105 patients reported by Diaz et al. 3 in 1991. In Korea, the incidence of bilateral fibroadenomas has been reported to be 9.3%, 5 and one case study reported three cases of ductal carcinoma in situ (DCIS) arising in fibroadenoma. 6 However, all DCIS of the three cases occurred from unilateral fibroadenoma. 6 To the best of our knowledge, simultaneous occurrence of bilateral DCIS lesions arising in bilateral juvenile fibroadenomas has never been reported in the Korean literature. Herein, we present an exceptional case of synchronous bilateral DCIS lesions arising within bilateral juvenile fibroadenomas. A 20-year-old Korean woman presented with bilateral, rapidly enlarging breast lumps for one month. Her past medical history was unremarkable, and she denied family history of breast malignancies. On physical examination, the bilateral lumps were found to be about 3 cm, painless, firm and movable. Axillary lymph nodes were not palpable. Ultrasonography (US) revealed a 2.4×1-cm, lobulated, hypoechoic mass in the right breast (Fig. 1A) and a 2.8×1.5-cm, oval hypoechoic mass in the left breast (Fig. 1B), favoring benign-looking nodules. US-guided core needle biopsy was performed on both breasts for histological examination. The core needle biopsy specimens showed pericanalicular and intracanalicular patterns of fibroad-enoma and epithelial hyperplasia with mild cytologic atypia, suggesting juvenile fibroadenoma. She underwent a lumpecto-my of both breasts for the impression of bilateral juvenile fibro-adenomas. Grossly, the right breast mass was a well-circum-scribed, lobulated, whitish, solid but softer than typical fibro-adenoma, measuring 2.4×2×1 cm, and the left breast mass was relatively circumscribed with a slightly irregular border, measuring 2.8×2.5×1.5 cm. On low-power view microscopic examination, atypical ductal cells with compacted or cribri-form, papillary patterns …