Predictive risk factors for lymph node metastasis in patients with resected non-small cell lung cancer: a case control study

Abstract

Background

Estimation of lymph node status is essential in order to determine precise therapy for patients with non-small cell lung cancer (NSCLC). Furthermore, lymph node involvement is a very powerful prognostic factor in these patients. In this analysis, we aim to evaluate the predictive factors for lymph node metastasis in NSCLC-patients.

Methods

In a prospectively-established database, we analyzed all data of patients with NSCLC, who underwent oncological surgical resections from 01/2007 to 12/2016, retrospectively. The correlation between clinicopathological parameters and lymph node metastasis was investigated by using univariate and binary logistic regression analysis.

Results

In this study, we operated on 204 consecutive patients, 142 men (71.7%) and 56 women (28.3%). Lymph node metastases were detected in 38.2% (78/204). Preoperatively, central tumor localization (OR = 2.6, 95% CI = 1.3–5.1, P = 0.005) and tumor size > 3 cm (OR = 2.5, 95% CI = 1.3–4.4, P = 0.005) were found to be significant predictive factors for lymph node metastasis. Postoperatively, multivariate analysis showed that intratumoral lymph vessel invasion (L1-status) (OR = 17.3, 95% CI = 5.1–58.4, P <  0.001) along with the central tumor localization (OR = 2.8, 95% CI = 1.4–5.8, P = 0.004) were significantly associated with lymph node metastasis. In small size tumors (≤3 cm), two predictive factors for lymph node metastasis were found: central tumor localization (OR = 19.4, 95% = 2.1–186.4, P = 0.01) and L1-status (OR = 43.9, 95% CI = 3.6–529.4, P = 0.003).

Conclusions

A precise pre- and intraoperative assessment of the lymph node status is essential in patients with larger sized tumors and central localization. Furthermore, L1-status is a highly significant risk factor for lymph node metastasis in NSCLC-Patients. Therefore, an adjuvant therapy in patients with L1-status and pNX category should be considered.