[Lung cancer and cigarette smoking in women. (Results of a case control study)]

Smoking habits of 297 female lung cancer patients (Kreyberg I: 202, Kreyberg II: 95) and 580 controls were analyzed. In addition tar exposures (TE) were calculated. Calculation of TE includes amount of consumptions, duration and the tar yields of all cigarette brands ever smoked. These are significant more smokers among patients (63%) and patients with a K I tumor (80%) compared to the controls (21%); K II: 29%. All patients and patients with a K I tumor had a significant longer smoking career (39.3 years; 39.6 years) and a higher tar exposure (TE = 1767; TE - 1810) compared to the controls (31.9 years, TE = 1146). K II: 37.4 years, TE = 1508. Lung cancer risks (adj. for TE) and population attributable risks (PAR) were: all age groups R = 7.3*, PAR = 54%; less than 40 years R = 1.1, PAR = 3%; 41-50 years R = 4.2*, PAR = 42% ; 51-60 years R = 7.6*, PAR = 62%; 61-70 years R = 7.8*, PAR = 54%; greater than 71 years R = 8.0*, PAR = 55%. Lung cancer risks (adj. for age) in relation to tar exposure and attributable risks (AR) were: TE less than 500: all cases R = 1.5, AT = 34% (KIR = 2.9, K II R = 0.8); TE 501-1000: all cases R = 4.2*, AR = 76% (KIR = 9.9*, K II R - 1.1): TE 1001-2000: all cases R = 12.1*, AR = 92% (KIR = 27.2*, K II R = 2.6**); TE 2001-3000: all cases R = 11.1*, AR = 91% (KIR = 25.2*, K II R = 2.0); TE greater than 3001: all cases R = 13.0*, AR = 92% (KIR = 29.3*, K II R = 3.3). These is a significant increase of risk of cigarette smokers beyond a TE of 501, which could be identified as a sort of critical exposure. There is a pronounced dose response relationship between cigarette smoking in relation to TE and lung cancer risk as concerning K I tumors but not KII tumors. Lung cancer risks in relation to age began smoking: less than 19 years R = 7.8*; 19 years and above R = 6.5*. *P less than 1%, **P less than 5%.