Background. Previous research has demonstrated that there is clustering of cancer among relatives of patients with lung cancer and that women may be at a greater risk than men, regardless of their smoking histories.
Methods. The authors conducted a study to test the hypotheses that this predisposition varies by the histologic type of tumor and that women with particular histologic types will report more first-degree relatives with cancer than will men with the same cell type. The analyses were based on 872 patients with histologically confirmed lung cancer who had been admitted to Roswell Park Cancer Institute, Buffalo, New York, between 1982 and 1987.
Results. More patients with squamous and large cell carcinomas reported two or more relatives with cancer, and overall, women reported more family history of cancer. Among patients with squamous cell carcinoma, this difference between men and women was significant ( P < 0.05). Among patients younger than 57 years, those with squamous cell were the most likely to report a family history of cancer ( P < 0.01). A similar trend was observed for smoking. Persons with small cell and squamow cell carcinomas who were nonsmokers or had smoked 1-20 years had three times the risk of a family history of cancer than did those with large cell and adenocarcinomas (odds ratio [OR] = 3.01; confidence interval [ci] = 1.38-6.63), in contrast to those who had smoked more than 20 years (OR = 0.85; ci = 0.62-1.62).
Conclusions. Squamous cell carcinoma is most associated with familial clustering of cancer, particularly among women, persons younger than 57 years, and individuals who smoked for fewer than 20 years. Cancer 1993; 72:1192-8.