Influence of postoperative complications on long-term outcome after oncologic lung resection surgery. Substudy of a randomized control trial

Lung resection surgery (LRS) causes an intense local and systemic inflammatory response. There is a relationship between inflammation and postoperative complications (POCs). Also, it has been proposed that the inflammation and complications related with the surgery may promote the recurrence of cancer and therefore deterioration of survival. We investigated the association between inflammatory biomarkers, severity of POCs and long-term outcome in patients who were discharged after LRS. This is a prospective substudy of a randomized control trial. We established three groups based in the presence of POCs evaluated by Clavien-Dindo (C-D) classification: Patients with no postoperative complications (No-POCs group) (C-D = 0), patients who developed light POCs (L-POCs group) (C-D = I-II), and major POCs (M-POCs group) (C-D = III, IV, or V). Kaplan–Meier curves and Cox regression model were created to compare survival and oncologic recurrence in those groups. Patients who developed POCs (light or major) had an increase in some inflammatory biomarkers (TNF-α, IL-6, IL-7, IL-8) compared with No-POCs group. This pro-inflammatory status plays a fundamental role in the appearance of POCs and therefore in a shorter life expectancy. Individuals in the M-POCs group had a higher risk of death (HR = 3.59, 95% CI 1.69 to 7.63) compared to individuals in the No-POCs group (p = 0.001). Patients of L-POCs group showed better survival than M-POCs group (HR = 2.16, 95% CI 1.00 to 4.65, p = 0.049). Besides, M-POCs patients had higher risk of recurrence in the first 2 years, when compared with L-POCs (p = 0,008) or with No-POCs (p = 0.002). In patients who are discharged after undergoing oncologic LRS, there is an association between POCs occurrence and long term outcome. Oncologist should pay special attention in patients who develop POCs after LRS.