The neutrophil to lymphocyte ratio can discriminate anaplastic thyroid cancer against poorly or well differentiated cancer.

PURPOSE

We evaluated the capability of the neutrophil to lymphocyte ratio (NLR) as a diagnostic tool to discriminate between poorly differentiated thyroid cancer (PDTC) and anaplastic thyroid cancer (ATC) from well differentiated thyroid cancer (WDTC).

METHODS

The NLR of 3,870 patients with benign and malignant thyroid tumors were analyzed. There were 436 benign, 3,364 papillary, 15 medullary, 34 follicular or hurthle type, 14 PDTC, and 7 ATC type neoplasms. Patients were divided into two groups: a high NLR group and a low NLR group.

RESULTS

The NLR of all 3,870 patients was a normal distribution, and the median value was 1.57. Advanced stage cancer, such as T3 or T4 was high (30.4% vs. 26.5%, P = 0.027), and cancer-specific deaths were also high (1.2% vs. 0.4%, P = 0.018) in the high NLR group. The proportion of PDTC (0.6% vs. 0.1%) and ATC (0.3% vs. 0.1%) was higher in the high NLR group. The NLR can discriminate between PTC, PDTC, and ATC (P = 0.035, P = 0.002, and P = 0.025, respectively), and the cutoff value was 3.8 between PDTC versus ATC. None of the NLR of PDTC exceeded the cutoff value of 3.8.

CONCLUSION

NLR can play a relevant role as a discriminating tool and may be considered as a new diagnostic criterion in discriminating as well as in selecting therapeutic approaches to these aggressive forms of thyroid cancer.