Second breast cancer following negative breast MRI: Analysis by interval from surgery and risk factors.

Objectives: This study aims to compare outcomes following a negative surveillance MRI study by surgery-MRI interval and investigate factors associated with second breast cancers in women with a personal history of breast cancer (PHBC). Methods: This retrospective study included 1552 consecutive women (mean age, 53 years) with a PHBC and a negative prevalence surveillance breast MRI result between August 2014 and December 2016. The incidence and characteristics of second breast cancers were reviewed and compared according to surgery-MRI interval (< 3 years vs ≥ 3 years). Logistic regression analysis was used to investigate associations with clinical-pathologic characteristics. Results: Twenty-five second breast cancers occurred after negative MRI. The incidence of second breast cancers or local-regional recurrence did not significantly differ by surgery-MRI interval. The median intervals between MRI to second breast cancer detection showed no significant difference between the two groups (surgery-MRI interval <3 years vs. ≥ 3 years). Two node-positive second breast cancers were detected in the group with <3 years interval. BRCA mutation status, receipt of breast-conserving surgery, and adjuvant chemotherapy (all p <.05) were significant factors associated with the development of second breast cancers. Conclusion: Outcomes following a negative surveillance MRI did not differ by surgery-MRI interval. BRCA mutation status, receipt of breast-conserving surgery and adjuvant chemotherapy were independently associated with the risk of developing second breast cancers after negative surveillance MRI. [ABSTRACT FROM AUTHOR]