A female patient with LFS, diagnosed by DNA sequencing of a blood sample in which heterozygous pathogenic TP53 mutations [1], c.818G > A (p.Arg273His), were identified, developed lymphocytic leukemia at the age of 11 and concurrent bilateral breast cancers (size, left: 11 mm × 6 mm, right: 25 mm × 13 mm) at the age of thirty. Here, TP53 is linked to breast cancer.