Does smoking or family history influence the prognosis of patients with non-small cell lung cancer?

The prognostic significance of pack-years smoked (PY) and family history of cancer (FH) was studied using the Cox proportional hazard model in 970 patients with non-small cell lung cancer. PY influenced survival only in women after other variables were adjusted [Hazard ratio (HR): 1.75 (1.45-2.11)]. FH also influenced survival with marginal significance in women with stage I disease [HR: 2.17 (0.89-5.29), p=0.088]. Furthermore, these two factors operated additively in women [HR for patients with both smoking and family histories over those without either: 2.25 (1.18-4.26)], but not in men.