Multicentricity and histopathological background features of familial breast cancers stratified by menopausal status

We investigated histopathological background and multicentricity in patients with familial breast cancers (FBCs) in comparison with these features in patients with sporadic breast cancers (SBCs), stratifying patients by menopausal status.

We collected a consecutive series of 469 FBC patients and 3334 SBC patients treated at our hospital between 1965 and 1995. The following criteria were used to define FBC, regardless of the presence or absence of a family history of other cancer or the patient's past history of malignancies: (1) Three or more second-degree relatives had been affected by breast cancer; (2) two first-degree relatives had been affected by breast cancer, and either one of them was under 40 years of age and/or had had bilateral breast cancers. The presence or absence of background proliferative lesions (PL; ductal/lobular hyperplasia and/or adenosis) and the multicentricity of breast carcinomas in FBCs and SBCs were analyzed for each group.

In premenopausal FBC patients, there was a non-significant trend towards a high frequency of multicentricity compared with findings in patients with SBCs overall (P = 0.087; odds ratio [OR], 1.43; 95% confidence interval [CI], 0.96-2.13). In premenopausal FBC patients, the frequency of background proliferative lesions with/or without fibroadenomas (FA) in the resected specimen was significantly higher than that in SBC patients overall (P = 0.001 for PL; OR, 1.47; 95% CI, 1.18-1.83; P < 0.001 for PL +/- FA; OR, 6.84; 95% CI, 4.93-9.49). With regard to the other clinicopathological factors examined, there were no significant differences between the two groups, except for the higher frequency of premenopausal patients among the FBC patients.

These results indicate that premenopausal patients with FBCs had more proliferative lesions in the histopathological background and more multicentric breast cancers than premenopausal patients with SBCs.