Outcome in patients with lung cancer found on lung cancer mass screening roentgenograms, but who did not subsequently consult a doctor.

GOALS OF THE STUDY: To evaluate the outcome in patients with lung cancer found on lung cancer mass screening roentgenograms, but who did not subsequently consult a doctor. PATIENTS AND METHODS: This study enrolled 198 asymptomatic patients with lung cancer found by lung cancer mass screening during the 9-year period. Five-year survival rates in patients who did not consult a doctor or who stopped consulting a doctor in spite of abnormal shadows detected on last mass screening chest roentgenograms (n=45, delayed consultation group) and in patients who subsequently consulted a doctor when abnormal shadows were detected (n=153, control group) were evaluated by the method of Kaplan and Meier and clinical variables were examined as possible predictors of survival time by the Cox proportional-hazards model. RESULTS: There was a significant difference between the 5-year survival rates in the delayed consultation group and in the control group (21 vs. 51%, log rank: P=0.0003, Wilcoxon: P=0.0009). The risk of death increased 115.0% for the 1-year delay in consultation (hazard ratio: 2.150, 95% CI: 1.203-3.842, P=0.0097). With regard to the reason why they did not consult a doctor, many of them answered that they did not have any respiratory symptoms. CONCLUSION: The 1-year delay in consultation had a great significance in that these patients did not receive any treatment for lung cancer for 1 year, and the 1-year delay in treatment itself affected the outcome.

Outcome in patients with lung cancer found retrospectively to have had evidence of disease on past lung cancer mass screening roentgenograms.

This study enrolled 143 asymptomatic patients with lung cancer detected by mass screening during an 8-year period (January 1, 1993 to December 31, 2000) and who had received a lung cancer mass screening roentgenogram one year before the disease was found. There was no difference between the 5-year survival rates in patients with one-year delayed detection of lung cancer (n=62) and in patients without (n=81) (46 vs. 58%, log rank: P=0.1330, Wilcoxon: P=0.1008). However, according to the tumor size on the overlooked chest roentgenogram, the outcome in stage I+II patients with missed tumors >20 mm in dimension (n=20) was worse than those with missed tumors <10 mm (n=24) or those with missed tumors 10-20 mm (n=18) (40 vs. 82 or 81%, log rank: P=0.0047, Wilcoxon: P=0.0010). All missed tumors in the lung field that did not overlap thoracic components were <10 mm in dimension and appeared as patchy ground-glass opacities, and they could not have been recognized if there was no other information that the tumor developed in that location. This might also be related to the lack of mortality effectiveness of previous lung cancer mass screening problem. Although it may be difficult to find the tumors <10 mm on a chest roentgenogram on mass screening, one-year delayed detection of lung cancer < or = 20 mm will not affect the prognosis.