In vivo assignment of methylmalonic acid in breast tissue using 2D MRS and relationship with breast density, menopausal status and cancer risk.

Two tentative assignments are made for MMA in breast tissue of women at elevated risk for cancer. BRCA-mutation carriers exhibited higher values of MMA than those with no known mutation. Premenopausal women with BRCA mutation and dense breasts recorded the highest levels of MMA compared with other categories.