Background and objectives: The aim of this study is to evaluate the relationship between the interval from first symptom to diagnosis (SDI) and the degree of invasion and survival in lung cancer.
Methods: Three hundred seventy-eight patients with lung cancer were included. SDI was defined as the time calculated from the cytohistologic confirmation of the diagnosis of cancer and the first symptoms noted by the patient and attributed to cancer by the physician. The degree of invasion was determined by TNM classification.
Results: The median SDI was 2.1 months, and did not correlate with stage. Survival decreased progressively according to TNM classification. Adjusting for age, sex, SDI and TNM, survival was influenced by age (RR=1.02) and by staging [Stage (Ib) RR=1.3; stage (IIIa) RR=2.6; stage (IIIb) RR=4.06; stage (IV) RR=7.5]. SDI was not found to affect survival (RR=1.01; 95% CI: 0.94-1.08). In the small cell group, SDI also failed to modify survival.
Conclusions: The results of this study indicate that SDI has no effect on the stage or survival of patients with lung cancer.