Nomograms for predicting recurrence and survival of invasive pathological stage IA non-small cell lung cancer treated by video assisted thoracoscopic surgery lobectomy

Background: A considerable portion of pathological stage (p-stage) IA non-small cell lung cancer (NSCLC) patients suffered from death and recurrence after video assisted thoracoscopic surgery (VATS) lobectomy. The purpose of our study was to develop nomograms to predict which subgroup patients were more likely to suffer from recurrence or death. Methods: Data of invasive p-stage IA NSCLC patients who underwent VATS lobectomy at Peking University People's Hospital from September 2006 to April 2014 were analyzed. Multivariate Cox proportional hazards regression was used to develop nomograms. The performance of the nomograms was evaluated by Harrell's concordance index (C-index), calibration plots and risk group stratification. Results: A total of 422 patients with NSCLC of invasive p-stage IA were included in the study. The median follow-up time was 40 months. Age [ hazards ratio (HR) = 1.067, 95% confidential interval (CI): 1.006-1.131], lymphovascular invasion (LVI) (HR=4.062, 95% CI: 1.278-12.912) and differentiation (HR =5.747, 95% CI: 2.151-15.353) were independent prognostic factors to predict overall survival (OS). Tumor diameter (HR = 3.299, 95% CI: 1.814-6.001), LVI (HR =3.260, 95% CI: 1.221-8.708) and differentiation (HR =3.607, 95% CI: 1.776-7.327) were independent predictors of recurrence free survival (RFS). The nomogram for predicting OS demonstrated stronger discriminatory power than the 7th and 8th T stage systems (C-index: 0.894 for the nomogram, 0.700 for the 7th T stage and 0.742 for the 8th T stage). Likewise, the C-index of the nomogram for predicting RFS was higher than that of the 7th and 8th T stage systems (0.838 for the nomogram, 0.670 for the 7th T stage and 0.723 for the 8th T stage). Conclusions: We developed nomograms that could predict individual accurate prognosis for invasive p-stage IA NSCLC patients after VATS lobectomy. Risk stratification by the nomograms might guide further adjuvant chemotherapy and follow-up.