The role of neutrophil to lymphocyte ratio in predicting lung metastasis in giant cell tumor of the extremities

OBJECTIVE: Inflammation has a vital role in tumor development and metastasis. Changes in blood count parameters have been associated with tumor prognosis. We aimed to evaluate the prognostic significance of neu- trophil to lymphocyte ratio (NLR) in predicting lung metastasis of giant cell tumors of the bone (GCTB) of the extremities. PATIENTS AND METHODS: 34 GCTB pa- tients (22 males and 12 females) were includ- ed in the study. Patients were divided into two groups. The metastasis group (n = 7) included GCTB patients with lung metastasis, while the non-metastasis group (n = 27) included those without lung metastasis. Descriptive statistics and frequency distribution were calculated [age, white blood cell (WBC), neutrophil, lymphocyte, platelets, neutrophil to lymphocyte ratio (NLR), and platelets to lymphocytes ratio (PLR)]. Con- tinuous normal variables were expressed as mean ± standard deviation and compared using Student’s t-tests. The receiver operating charac- teristic (ROC) curve analysis was used to eval- uate the ability of NLR and PLR to predict lung metastasis. The factors were considered to be statistically significant at p < 0.05. RESULTS: There were no significant differ- ences between the lymphocyte count (1.81 vs. 2.23 103/mm3 ), platelet count (436 vs. 364 103/ mm3 ), and PLR values (247 vs. 190) of the two groups (p > 0.05). The WBC count (11.8 vs. 8.95 103/mm3), neutrophil count (8.78 vs. 5.69 103/mm3), and NLR levels (5.45 vs. 2.81) (p < 0.05) were significantly higher in the metasta- sis group. The presence of an NLR cut-off val- ue of 3.7 significantly predicted the existence of lung metastasis (AUC = 0.857 [95%CI = 0.714-1], p = 0.004) with a sensitivity of 85% and specific- ity of 82%. CONCLUSIONS: NLR may serve as a prom- ising prognostic marker for predicting lung me- tastasis in GCTB patients.