It is possible that tumour-infiltrating granulocytes promote tumour progression

Several lines of evidence indicate that tumour-infiltrating granulocytes (TIGs) promote tumour growth and progression. However, the prognostic significance of TIGs, the relationship between TIGs and Fas ligand (FasL) expressed on tumour cells remains unclear and warrants investigation. Using immunnostaining, we retrospectively investigated TIGs and FasL in 130 tissue specimens from gastric carcinoma. We analyzed the correlation among these markers, their association with clinicopathologic features and prognosis. The number of TIGs was significantly associated with FasL-expression (P=0.002). Further, TIGs were significantly associated with depth of tumour invasion, lymph node metastasis and tumour stage. Calculating the prognostic relevance, in multivariate analysis, TIGs [relative risk (RR)=1.014; 95% CI=1.002-1.027; P=0.015] and tumour stage were statistically significant factors for survival. Our results suggest that TIGs are conveniently measured by the immunostaining method, and possibly serve as an independent factor of prognosis in patients with gastric carcinoma. This is based on the fact that TIGs were significantly associated with tumour stage and shorter survival time.