Prognostic implications of ductal carcinoma components in -positive breast cancer: a retrospective cohort study.

PURPOSE

Although the breast cancer susceptibility gene -associated invasive breast cancer is well studied, there are limited reports on ductal carcinoma (DCIS) in patients with mutations. This study aims to evaluate the differential prognostic effect of DCIS in breast cancer patients with pathologic variants of genes.

METHODS

Breast cancer patients who tested positive for mutations between August 2003 and January 2022 at a single tertiary referral center were retrospectively analyzed. Survival outcomes were compared between patients with both invasive ductal carcinoma (IDC) and DCIS (IDC-DCIS group, n = 121) and those with IDC alone (IDC group, n = 36).

RESULTS

Of the 157 patients, 65 (41.4%) exhibited mutations in , 90 (57.3%) in , and 2 (1.3%) in both . DCIS components were more frequently found in pathological variants (, 46 [38.0%] , 76 [62.4%]; P = 0.030). No statistically significant difference was found in 10-year recurrence-free survival (IDC-DCIS, 89.3% IDC, 83.6%; P = 0.989). Subgroup analysis indicated that the DCIS component correlated with improved survival outcomes in the subgroup ( IDC-DCIS, 85.5% IDC, 51.0%; P = 0.024). Conversely, in the subgroup, IDC-DCIS patients exhibited a worse prognosis ( IDC-DCIS, 85.5% IDC-DCIS, 65.8%; P = 0.045).

CONCLUSION

The presence of a DCIS component carries varied prognostic significance in and mutations. A tailored approach may be necessary when determining treatment options for breast cancer patients with mutations based on the presence of DCIS.