[Skip to Content]
[Skip to Content Landing]
July 10, 1967

In Situ Lobular CarcinomaA Prospective Follow-Up Study Indicating Cumulative Patient Risks

Author Affiliations

From the Department of Pathology, Memorial Hospital for Cancer and Allied Diseases and the James Ewing Hospital of the City of New York.

JAMA. 1967;201(2):82-86. doi:10.1001/jama.1967.03130020028006

In situ lobular carcinoma is a preinvasive form of breast cancer which if inadequately treated will frequently progress to infiltrative cancer. A follow-up study of 50 patients with in situ lobular carcinoma, treated in most instances by local excision, reveals the following subsequent cumulative risk of infiltration: 8% after five years, 15% after ten years, 27% after 15 years, and 35% after 20 years. After 23 years, the cumulative risk is thought to exceed 50%. In addition, the cumulative risk of cancer developing in the breasts contralateral to those in which in situ lobular carcinoma was found was 10% after ten years, 15% after 15 years, and 25% after 20 years. The cumulative risk of contralateral breast cancer after 22 years appears to exceed 30%.