Hospital effect on 3-years-survival in patients undergone to lung tumor surgery: a real-world study.

Context It is debated in literature the association between surgical volume and clinical outcomes in cancer patients. Objectives Aim of our study was to investigate the factors associated with death for any cause among patients undergone to lung cancer surgery. In particular, to assess whether and how much i) patients’ characteristics and ii) the hospital where the patient is admitted and its volume of activity, affect the risk of 3-year death. Methods Data were retrieved from the administrative databases of Lombardy Region (Italy). Residents of Lombardy Region, older than 18 years, with at least one hospital admission for lung resection during 2009 were identified. 802 patients were included in the final cohort and followed up to 3 years (December 31, 2012). Death for any cause after 3 years and the time to death were the outcomes of interest. Generalized linear mixed effects models and frailty Cox survival models were fitted in order to quantify the effect of selected factors on the outcome. Results After adjusted for the patient’s characteristics, the analysis showed a remarkable impact of hospital on the risk of death. The survival probabilities of a patient with “average” characteristics (i.e., man, 65 years, not polymormid) undergone to a complete pneumonectomy but in a hospital characterized by a “positive” random effect has a higher probability of survival (80%) compared to a patient who underwent an ordinary complex surgery in a hospital characterized by a “negative” random effect (73%). Furthermore, patients admitted to hospital with more than 10 surgeries per year have a lower probability of death (-29%) with respect to those admitted to hospital with less than 10 surgical operations per year. Conclusions Although the 3-year mortality after lung cancer surgery is mainly affected by individuals factors, the hospital where the patient was admitted accounts for a significant proportion of outcome variability. Among the hospital characteristics, the surgical volume played a central role