Importance: Current lung cancer guidelines recommend lymph node sampling (LNS) with the 3 + 1 rule, which recommends station-based sampling with at least 3 N2 (mediastinal) and 1 N1 (hilar) nodal stations. Although there is oncologic benefit to rigorous LNS, potential negative impacts on surgical outcomes have not been well investigated. As adoption of the 3 + 1 rule increases given its formalization as guideline-concordant care, associations with adverse outcomes are crucial to characterize. Objective: To evaluate whether satisfying the 3 + 1 rule is associated with increased postoperative complications. Design, Setting, and Participants: This retrospective cohort study used the Society of Thoracic Surgeons General Thoracic Database, which was queried for patients with clinical stage T1 to T3, N0, M0 non-small cell lung cancer (NSCLC) who underwent surgical resection with known LNS between July 1, 2021, and January 1, 2023. Statistical analysis was performed from March 2024 to March 2025. Exposure: A propensity match was conducted to compare the postoperative complication rate by 3 + 1 LNS status. Main Outcomes and Measures: Data on demographic characteristics were collected and analyzed. Primary outcomes included postoperative complications, such as arrhythmias, pleural effusion requiring drainage, blood transfusion, prolonged air leak, therapeutic bronchoscopy, pneumonia, respiratory failure, bronchopleural fistula, pulmonary embolism, pneumothorax, prolonged ventilatory support, myocardial infarction, and sepsis. Thirty-day mortality and readmission rates were also evaluated. Results: The cohort included 28 439 patients (median IQR age, 69 66-75 years; 4791 59.5% female). There were 18 939 patients (66.6%) who satisfied the 3 + 1 rule. In the unadjusted group, the 3 + 1 cohort had longer median (IQR) operating room duration (224 178-281 vs 210 161-273 minutes, P < .001) and rates of pathologic upstaging (2520 13.3% vs 922 9.7%, P < .001). In the postmatch analysis, there were no other significant differences in postoperative complication rates, and the aforementioned associations in the 3 + 1 group were no longer observed. Conclusions and Relevance: In this cohort study of patients with NSCLC, the 3 + 1 rule was not associated with increased postoperative complications. This study's findings suggest support for the continued use of this strategy in terms of overall safety profile.
Madeka et al. (Mon,) studied this question.