The granulocyte/lymphocyte ratio as an independent predictor of tumour growth, metastasis and progression: Its clinical applications

Several investigators have suggested that the granulocyte/lymphocyte (G/L) ratio is a good indicator for the evaluation of the condition of a tumour-bearing host, although its prognotic significance is unclear. To further investigate the clinical applications of the G/L ratio, we injected 1x105 and 1x106 Lewis lung carcinoma cells (3LLc) into the feet of 4-week-old C57BL/6 mice separated into groups A, B, C and D (1x105 cells) and E, F, G and H (1x106 cells). For the observation of tumour metastasis and G/L ratio, the mice in groups A-D were sacrificed on days 11, 14, 17 and 21 after inoculation with the 3LLc cells, and the mice in groups E-H on days 7, 11, 14 and 17. The results suggest that in mice the number of granulocytes increases with time after 3LLc cell injection (P<0.05). We also retrospectively investigated the correlation between G/L ratio, clinicopathologic features and prognosis in 62 patients with gastric carcinoma. There was a significant correlation between the G/L ratio and tumour weight (r=0.746, P<0.05), as well as a significant difference between the G/L ratio and the extent of metastases (P<0.05). Additionally, the G/L ratio was significantly associated with lymph node metastasis and higher tumour stage, tumour progression (P=0.017) and 5-year survival (P=0.013). In conclusion, the G/L ratio is associated with tumour progression and shorter survival. The close correlation between G/L ratio and tumour stage or lymph node status suggests that it could be used to predict tumour metastasis, prognosis and overall survival in patients with gastric carcinoma before they undergo surgical treatment.