Progression risk of columnar cell lesions of the breast diagnosed in core needle biopsies

Columnar cell lesions (CCLs) of the breast are recognized as putative precursor lesions of invasive carcinoma, but their management remains controversial. We therefore conducted a retrospective study on 311 CCLs, diagnosed in 4,164 14-gauge core needle biopsies (CNB): 221 CCLs without atypia (CCL), 69 with atypia (CCL-A), and 21 atypical ductal hyperplasias originating in CCL (ADH-CCL). Two groups were identified: "immediate treatment" group undergoing excision within four months after the CNB diagnosis of CCL (N = 52) and the "wait-and-see" group followed up to 8 years (median 3.5 years, N = 259). In 7 of 31 women (22.5%, 1 CCL, 4 CCL-A, 2 ADH-CCL) who underwent immediate surgical excision and were initially biopsied for microcalcifications, ductal carcinoma in situ (DCIS) was present and in 2/31 women (6.5%, 1 CCL, 1 CCL-A) invasive carcinoma. In 2/21 excisions (9.5%, 1 CCL, 1 CCL-A) initially biopsied for a density, DCIS was present and invasive carcinoma in 5/21 excisions (23.8%, 2 CCL, 3 CCL-A). In the wait-and-see group, 9/259 women (3.5%) developed invasive carcinoma, 6 ipsi, and 3 contralaterally. Progression risks of CCL-A and ADH-CCL were 18% and 22%,versus 2% for CCL without atypia (p < 0.001). In conclusion, CCL-A or ADH-CCL in a CNB were associated with a high risk of DCIS/invasive carcinoma in immediate surgical excision biopsies. The 8-years progression risks for CCL-A and ADH-CCL were around 20%. This illustrates that an atypical CCL in a CNB may signal the presence of concurrent lesions or development of advanced lesions in future and may justify ("mini") surgical excision.