Relative risk of developing lung cancer in Hodgkin lymphoma by treatment modality and smoking status

Radiation: radiation ≥5 Gy to specific location in the lung where cancer was diagnosed. Smoking: estimated smoking habit five years before diagnosis date of lung cancer. Smokers include those smoking one or more packs of cigarettes per day. Those smoking less than this amount, former cigarette smokers, and smokers of pipes or cigars were considered to be non-smokers in this analysis.