Is there a role for pre-operative thrombocytosis in the management of colorectal cancer?

BACKGROUND: High circulating platelet counts have been associated with poor prognosis in a variety of solid tumours such as breast, renal and lung cancer. We investigated the significance of a high pre-operative platelet count on overall survival in patients with stages I-IV colorectal cancer. PATIENTS AND METHODS: 630 Consecutive patients who colorectal cancer resection between 2004 and 2007 with a full blood count taken 14 days prior to the surgery were assessed. Male:female 7:5, median (range) age 73 (40-99 years). Thrombocytosis was defined as platelet count of ≥450 × 10(9)/L. The relationship between platelet count, pathological features and overall survival was assessed. RESULTS: : Mantel-Cox regression showed that platelet count does not predict survival on multivariate analysis (p = 0.067). Thrombocytosis was present in 51/627 (8.1%) of cases. There was no statistically significant difference in mean survival (p = 0.067) observed in patients with platelet count <450 × 10(9)/L (n = 576; 95%CI: 1550.5-1405.4 SE 37.0) versus ≥450 × 10(9)/L (n = 51, CI: 1261.6-955.0, SE 78.2). There was also no correlation between Dukes stage and thrombocytosis. CONCLUSION(S): In our study, pre-operative thrombocytosis is not a prognostic indicator of survival in colorectal cancer patients regardless of pathological stage.