A histological analysis was conducted in 138 female breast cancer patients, and 
the results were classified in accordance with "Histological Typing of Breast 
Tumours" (WHO, Geneva 1981). Since about half of these tumors showed more than 
one histological type of carcinoma, a simplified classification system with four 
groups was adopted. When patients were categorized according to the number and 
degree of kinship of their relatives with breast cancer, no specific association 
with the histological types was found. Familial tumors also encompassed a wide 
spectrum of histopathologic diagnoses. This suggests the absence of a 
histological marker in familial breast cancer. Pedigrees of all the patients 
were then analyzed, special emphasis being placed on relatives suffering from 
the same and other malignancies. It was found that 13.8% of the probands had at 
least one first-degree relative with breast cancer and that, compared with the 
tumor spectra in the male and female population, there was a significantly 
higher number of esophageal carcinomas in the fathers, of stomach cancers in the 
uncles and grandfathers, of brain tumors in the mothers, and of sarcomas in the 
brothers. An accumulation of the same tumors, especially stomach cancer and 
tumors related to the SBLA syndrome, was observed in families of index patients 
with tubular or medullary breast cancer. The SBLA syndrome is a complex familial 
cancer syndrome characterized by a proclivity to Sarcomas, Breast cancers, brain 
tumors, Lung and laryngeal cancers, leukemia, and Adrenocortical carcinomas.