The role of plasma D‐dimer levels for predicting lymph node and mediastinal lymph node involvement in non‐small cell lung cancer

INTRODUCTION: Elevated plasma D-dimer levels have been suggested as a predictor of poor prognosis in NSCLC. But rare study showed the relationship between D-dimer levels and lymph node involvement. OBJECTIVES: To evaluate the role of plasma D-dimer levels in predicting lymph node and mediastinal lymph node involvement in NSCLC. METHODS: Preoperative plasma D-dimer levels were quantified in 253 NSCLC patients that underwent radical lung resection with systemic lymph node dissection. Patients were classified as lymph node negative (N0) versus lymph node positive (N1 + N2) and mediastinal lymph node negative (N0 + N1) versus mediastinal lymph node positive (N2). RESULTS: Median plasma D-dimer level was significantly lower in Group N0 (94.0 μg/L) compared to Group N1 + N2 (177.0 μg/L) and in Group N0 + N1 (122.0 μg/L) compared to Group N2 (198.0 μg/L). Similar results were found in patients stratified by age, sex, smoking status and histological type, expect in patients with squamous carcinoma. The Receiver Operating Characteristic (ROC) curve for plasma D-dimer levels of N0 versus N1 + N2 showed an area under the curve (AUC) of 0.757 and when a cutoff value was 124.0 μg/L DDU, the sensitivity and specificity was 0.80 and 0.68. The ROC curve for plasma D-dimer levels of N0 + N1 versus N2 showed an AUC of 0.720 and when a cutoff value was 147.0 μg/L DDU, the sensitivity and specificity was 0.75 and 0.67. CONCLUSIONS: Plasma D-dimer level has utility for predicting lymph node and mediastinal lymph node status in patients with operable NSCLC.