Risk factors of lymph node metastasis in lung squamous cell carcinoma of 3 cm or less in diameter

Through literature review we cannot find an efficient risk factor of lymph node metastasis in lung squamous cell carcinoma (SCC). This study aimed to investigate the risk factors of pathological lymph node status in patients with lung SCC of 3 cm or less in diameter, to provide some reference for the fellow surgeons in the decision of operative option. In total, we analyzed 154 patients with lung SCC of 3 cm or less in diameter who underwent lobectomy or bilobectomy or pneumonectomy with systematic lymph node dissection. The relationship between lymph node status and clinical characteristics were examined. Lymph node metastases were present in 48 patients (31.2%) of the study subjects. Multivariate analysis indicated that, age <60 years old (P = .007), tumor location of central-type (P = .003), tumor long axis >2 cm but ≤3 cm (P = .047) were associated with lymph node metastasis, and their odd ratios (OR) were 3.120, 3.359, and 5.196, respectively. Group analysis of the 74 peripheral lung SCC showed that those with the tumor long axis ≤2 cm had a lower rate of lymph node metastasis (7.9% vs 27.8%, P = .025). Age <60 years old, tumor location of central-type, and tumor long axis >2 cm but ≤3 cm are risk factors of lymph node metastasis in lung SCC. Systematic lymph node dissection or sampling is recommended when tumor central-type location and/or long axis >2 cm in lung SCC are present.