Active surveillance for patients with multifocal ground-glass nodules: protocol of a prospective, multi-center, single-arm trial (ECTOP-1021).

Background: For early-stage lung cancers identified as ground-glass opacity (GGO) on thin-section computed tomography (TSCT), the previously proposed concept of the surgical curative time window suggests that surgical resection is deemed appropriate at any point within this timeframe, eliminating the necessity for immediate surgery upon initial detection. However, uncertainties persist regarding the impact of delayed surgery on survival and the optimal timing of surgery within a surveillance context. Methods: The Eastern Cooperative Thoracic Oncology Project-1021 (ECTOP-1021) (ClinicalTrials.gov, NCT06097910) is a prospective, multi-center, single-arm trial designed to evaluate the safety of active surveillance for patients with early-stage multifocal ground-glass nodules (GGNs). Patients with persistent GGNs, characterized by a tumor diameter ≤2 cm, consolidation-to-tumor ratio (CTR) ≤0.25, and the presence of three or more lesions, will be enrolled. Regular TSCT scans will be conducted according to a predefined follow-up schedule, and surgery will be performed when resection criteria are met. The primary endpoint is 5-year overall survival (OS). The study aims to enroll a total of 370 patients from centers and hospitals within the ECTOP study group over a 3-year period. Discussion: The trial will establish the surveillance strategy, involving the avoidance or delay of surgery within the surgical curative time window, as a standard treatment for patients with multifocal GGNs. Trial Registration: This trial is officially registered on ClinicalTrials.gov (NCT06097910).