Long term clinical follow-up of atypical ductal hyperplasia and lobular carcinoma in situ in breast core needle biopsies

Atypical ductal hyperplasia (ADH) and lobular carcinoma in situ (LCIS) may be associated with a relatively high incidence of invasive carcinoma and ductal carcinoma in situ (DCIS) on immediate excision when found on core needle biopsy of the breast. However, the long term significance of ADH and LCIS in a breast core needle biopsy is not as well characterised. We reviewed the results of all breast core needle biopsies with a diagnosis of ADH or LCIS and immediate excision from the years 2000-2004, and correlated the results with long term clinical follow-up. Of 175 biopsies with ADH, 53 (30.3%) had carcinoma (8 invasive, and 45 DCIS) at the time of immediate re-excision. Of 69 biopsies with LCIS, three (4.3%) had carcinoma (2 invasive, and 1 DCIS) at the time of immediate re-excision. A total of 14 (11.5%) patients with ADH and benign re-excisions developed invasive carcinoma (12) or DCIS (2) on follow-up. A total of 17 (25.8%) patients with LCIS and benign reexcisions developed invasive carcinoma (13) or DCIS (4) on follow-up. The risk of invasive carcinoma or DCIS on immediate re-excision was significantly higher for women with ADH than LCIS (p < 0.001). Women with LCIS developed significantly more invasive carcinomas and DCIS than women with ADH on long term follow-up (p = 0.01). Compared to women with fibrocystic changes (FCC) on core needle biopsy, the risk of developing invasive carcinoma or DCIS was significantly higher for women with ADH and benign initial re-excisions (95% CI 1.092-7.297, p = 0.03), and women with LCIS and benign re-excisions (95% CI 3.028-18.657, p < 0.001). Overall, 67/175 (38.3%) women with ADH and 20/69 (29.0%) women with LCIS on core needle biopsy either had carcinoma at the time of the biopsy or later developed carcinoma. Significantly more women with LCIS developed invasive carcinoma or DCIS than women with ADH on long term follow-up. The relative risk for ADH and LCIS on core biopsy with a negative excision compared with FCC was similar to that reported in the literature (ADH 1-7x, LCIS 3-19x).