Estimating the Cure Proportion in Stage IA Lung Adenocarcinoma: A population-based study

Abstract Objectives Using a mixed cure model, this study aimed to investigate factors influencing the cure, recurrence, and metastasis of stage IA lung adenocarcinoma. Materials and Methods A total of 1,064 patients who underwent video-assisted thoracoscopic pneumonectomy were included. Variable screening was performed using the random forest algorithm and least absolute shrinkage and selection operator. The mixed cure model was used to identify factors affecting patient cure and survival, and a sequential analysis was performed on 5%, 10%, and 20% of the presentational subtype simultaneously. The receiver operating characteristic was used to explore the best model and to construct a nomogram for predicting cure rate. Results The median follow-up was 58 (range: 3–115) months. Results from the cure part of the mixed model indicated that the predominant subtype, presentational subtype, and tumor diameter were prognostic factors affecting the patients' cure rate. Based on these factors, a nomogram was constructed to predict the cure rate. The survival part indicated that the predominant subtype was the only factor influencing patients' recurrence and metastasis. A sequential analysis of the presentational subtype showed no significant effect on survival ( P > 0.05). Regardless of the recording mode, no significant improvement was observed in the model's discriminative ability. Only a few postoperative pathological specimens showed lymphovascular invasion (LVI); however, the survival curve suggested a significant effect on patient survival. Conclusion After excluding the existence of long-term survivors, the predominant subtype was the only factor influencing patient recurrence and metastasis. Although LVI is rare in stage IA, its significance for patient prognosis cannot be ignored.