Multicentricity in breast cancer. A study of 366 cases.

A total of 366 consecutive modified radical mastectomy specimens were studied for determination of multicentricity. The authors found that 187 samples (49.1%) were multicentric. Ten specimens contained in situ carcinoma without an infiltrating component; eight of them were multicentric. Multicentricity was correlated with various laboratory and clinical features, including patient age, tumor size, histologic type of breast cancer, tumor grade, presence and values of estrogen and progesterone receptors, the amount of solid tissue in the breast, and the family history. The data were organized in eight independent dimensions, four ordinal and four cardinal. Correlation analysis was applied to a cross tabulation supplemented with other statistical tests. The authors found that the factors related to multicentricity were the age of the patient, the size and the histologic type of the tumor, levels of the progesterone receptors more than 50 fmol/mg of protein, and the amount of solid tissue in the breasts. Tumor grade, estrogen receptors levels, and family history were not related to multicentricity. It was concluded that multicentricity is a frequent property of breast cancer. It is more common in young and perimenopausal women. Multicentricity occurs in small tumors but is, more common in larger ones.