Prognostic factors and patients' profile in treated stage I and II lung adenocarcinoma: a Hospital's Cancer Registry-based analysis.

Background: It is known that survival from lung cancer can differ between countries and even between different regions of the same country. The variability between hospitals, the age and social profile, and the time when this patient was treated, can influence survival, and these factors are intrinsic to each region. Knowing the profile of patients, hospitals, and other factors associated with the treatment of stage I and II lung cancer in a given region is important to understand outcomes and propose improvements that can be replicated in any region of the world that presents the same profile of patients and care structure. This study evaluates survival and possible predictors in all patients with stage I and II lung cancer adenocarcinoma through the Hospital's Cancer Registry (HCR), responsible for the State of Sao Paulo's cancer registry, a geographical area with 40 million inhabitants.

Methods: Based on the HCR, an observational study was conducted, including 1,278 patients diagnosed with lung adenocarcinoma at clinical stages (CS) I and II. Sex, age at diagnosis, education, neighbourhood, CS at diagnosis, the time between diagnosis and treatment, 5-year periods in which patients were treated, treatment modality and hospitals where patients were treated were analysed. Cox univariate and multiple regression analyses were used to estimate the hazard ratio (HR).

Results: A total of 1,278 lung cancer patients with clinical lung cancer adenocarcinoma stages I and II were included. About 40.06% of patients did not receive surgery, and only 55.8% started the treatment within 2 months. The majority of the patients were treated in high complexity hospitals, 69%. Five-year overall survival (OS) was 45.6% in CS I and 27.5% in CS II. Patients treated in high complexity centres have lower mortality rates than those treated in Partial Hospital Complexity Centers in Oncology (PHCCO) (adjHR 1.18; 95% CI: 1.00-1.40; P=0.047). Patients diagnosed between 2010-2014 had a protective factor against the risk of death concerning patients diagnosed between 2000-2004.

Conclusions: The 5-year OS has significantly improved as long as the 5-year group analysed. Also, the 5-year OS of the patients treated in high complexity hospitals is higher than those treated in PHCCO.