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.