Many questions remain about the direct and indirect costs to families incurred during the course of cancer care. Despite availability, many patients fail to access co-pay assistance programs. The Cancer Support Community and Genentech piloted a national survey investigating psychosocial barriers to accessing co-pay assistance and the hidden costs of care. Methods: Cancer patients (n=79) diagnosed over 6 months ago or had active treatment within 2 years and caregivers (n=29) of patients who met the above criteria, completed a survey that included the Revised Impact of Event Scale to assess intrusive and avoidant ideation around the cost of care. Although the effect of smoking on lung cancer incidence is well known, it is not yet known if continued smoking after diagnosis affects prognosis. Methods We systematically searched for studies that measured the effect of quitting smoking after diagnosis of lung cancer on prognosis. Two researchers independently identified studies to include and extracted data. Estimates were combined using a random effects model and I2 statistic was calculated to examine heterogeneity. Using life tables, we modelled 5-year survival for non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) using death rates for continuing smokers and quitters obtained from the review. Data sources We searched CINAHL (from 1981), EMBASE (from 1980), MEDLINE (from 1966), Web of science (from 1966) and CENTRAL (from 1977) to December 2008 and the reference lists of included studies. Results Continued smoking was associated with an increased risk of all-cause mortality and recurrence in early stage NSCLC ((HR 2.94 95% CI (1.15, 7.54) , HR 1.86 (1.01, 3.41) ) and with an increased risk of all-cause mortality, development of second primary and recurrence in limited stage SCLC ((HR 1.86 (1.33, 2.59) , HR 4.31 (1.09, 16.98) and HR 1.26 (1.06, 1.50) . Life table modelling estimated 41% 5-year survival in 65-year old NSCLC continuing smokers compared to 75% in quitters. In SCLC, an estimated 36% of continuing smokers survive for five years compared to 68% quitters. Conclusions There is evidence that smoking cessation after diagnosis of lung cancer is associated with improved prognosis. Assuming causality, the number of deaths prevented is larger than would be expected due to reduction of cardio-respiratory deaths after smoking cessation and it is likely the majority of the mortality gain is due to reduced cancer progression.