Impact of pretreatment thrombocytosis on blood-borne metastasis and prognosis of primary gastric cancer.

Abstract

e14504 Background: Thrombocytosis has been associated with malignancies and poor prognostic implications in cancer patients. In the present study the prognostic significance of pretreatment platelet (PLT) level was assessed with regard to recurrence and survival in patients with primary gastric adenocarcinoma. Methods: The authors reviewed the prospective data of 1,593 gastric cancer patients who received curative gastrectomy with extended lymphadenectomy. The correlations of PLT level with recurrence and overall survival were evaluated by both univariate and multivariate analyses. Results: Thrombocytosis (≥ 40 x 104/μL) was present in 6.4% of the patients prior to curative surgery. Thrombocytosis was more frequently associated with advanced T and N stage, larger tumor size, anemia, and old age (p<0.05). The 5-year survival rate of patients with thrombocytosis was significantly worse than that of patients without thrombocytosis (56.9% vs. 65.5%; p=0.043). The recurrence rate was higher, mainly attributed to the frequent hematogenous spread, in patients with thrombocytosis than in those without thrombocytosis (51.0% vs. 34.5%; p<0.001). Furthermore, thrombocytosis was an independent risk factor of recurrence (Odds ratio 1.649 [95% CI 1.074 – 2.531], p=0.022), along with serosa invasion and nodal metastasis. Conclusions: Pretreatment thrombocytosis correlated significantly with poor prognosis and can be used as an independent predictor of recurrence by blood-borne metastasis in gastric cancer.