Background: Breast cancer is the most common cancer and the second leading cause of cancer death among women in the United States; annual breast cancer deaths are exceeded only by those for lung cancer.
Methods: Data from the Surveillance, Epidemiology, and End Results (SEER) program registry of the National Cancer Institute comprising 158,621 invasive and 10,639 in situ cases of microscopically confirmed breast carcinomas registered for the years 1973-1987 have been analyzed. Relative frequencies, incidence rates, and 5-year relative survival rates were examined by selected variables of interest. Invasive and in situ breast carcinomas and sarcomas were analyzed separately.
Results: Infiltrating duct carcinoma was the largest group of female breast cancer, constituting 67.9% of the total with a 5-year relative survival of 79%. All other invasive carcinomas were compared with this group. Lobular carcinoma was the second largest group, only 6.3%, and a 5-year relative survival of 84%. Medullary carcinoma was the third most common with 2.8% and a 5-year relative survival of 82%. Other types included mucinous (colloid) adenocarcinoma, 2.2%, 5-year relative survival of 95%; comedocarcinoma, 1.4%, 5-year relative survival of 87%; Paget's disease (nipple and other breast), 1.1%, 5-year relative survival of 79%; papillary carcinoma, 0.9%, 5-year relative survival of 95%; tubular adenocarcinoma, 0.7%, 5-year relative survival of 96% and inflammatory carcinoma, 0.5%, 5-year relative survival of 18%. Carcinoma in situ was registered as intraductal, lobular, combined ductal and lobular, papillary, and carcinoma in situ, not otherwise specified. The relative survival for all forms of carcinomas in situ was approximately 100%. Sarcomas and malignant tumors not further classified are also considered.
Conclusions: The various histologic types of breast cancer exhibit differences in regard to relative frequency, site pattern within the breast, and patient survival. The SEER program data base of breast cancer is the largest single population-based reference source for breast cancer in the United States. This program is a valuable resource for information on frequency, percentage, and incidence rates by histologic type as well as survival rates of patients with breast cancer.