Familial Cancer Prevalence Spanning Eight Years: Family N

Family N, a family with an extraordinarily high frequency of adenocarcinoma in specific branches of the family, consistent with the cancer family syndrome, has been extensively investigated. During an eight-year period, cancer was found to have occurred in 21 additional family members. Six of the individuals in whom cancer had been previously ascertained, 28% of those who developed cancer during this eight-year period, were found to have acquired additional primary cancers. One of them had four separate primary cancers, and another one had three. Pedigree analyses have shown repeatedly that individuals from particular lineages tend to develop cancers of specific anatomic sites. It is suggested that gene-transmitted constitutional differences may interact with nongenetic factors, possibly oncogenic viruses, to produce cancer in such family members who are at relatively high risk. Cancer control programs utilizing established familial risk information should be developed for better management of these familial cancer problems.