An investigation to determine whether clusters of cancer types exist in nine breast-ovary families.

Monte-Carlo simulations were carried out on nine BRCA1-linked families selected from the 1993 Breast Cancer Linkage Consortium. These families all displayed a prevalence of both breast and ovarian cancers, but little evidence was found to conclude that sufferers of either type formed clusters in particular branches of families. It was noted that the application of these methods to larger pedigrees with known probands would be useful in further clarifying the issue.