Overall survival and prognostic factors in Stage I lung adenocarcinoma treated with curative intent: A real-life 19-year cohort study

Objectives: Important differences in Stage I non-small-cell lung cancer (NSCLC) are related to the delay in the diagnosis to the treatment, hospitals' specialised status, comorbidities, tumour stage and histological type.

Methods: A 19-year retrospective cohort study was conducted, including 681 patients with NSCLC in clinical-stage IA-IB. The variables analysed were gender, age, schooling, type of health care provider, type of treatment, period of 5-year treatment, the time between first attendance to diagnosis and the time between diagnosis and treatment, and hospital's specialised status.

Results: Patients who underwent radiotherapy alone had three times more risk of death than those who underwent surgery alone (adjusted hazard ratio [adjHR] = 3.44; 95% confidence interval [CI]: 2.45-4.82; p <0.001). The independent risk of death factors was being treated in nonhigh complexity centres in oncology hospitals and having started the treatment more than 2 months after diagnosis (adjHR = 1.80; 95% CI: 1.26-2.56; p <0.001) and (adjHR = 2.00; 95% CI: 1.33-3.00; p <0.001), respectively. In addition, the patients diagnosed between 2011 and 2015 had a 40% lower risk of death when compared to those diagnosed between 2000 and 2005 (95% CI: 0.38-0.94; p = 0.027).

Conclusion: The overall survival in curative intent Stage-I lung cancer patients' treatment was associated with the 5-year diagnosis group, the delayed time between diagnosis and treatment and the hospital qualification.