The prognostic significance of thrombocytosis in epithelial ovarian carcinoma

Abstract

Objective. The objective of this study was to determine the incidence of thrombocytosis in epithelial ovarian carcinoma and examine associations with clinico-pathologic features. Thrombocytosis (platelet counts >400 × 10 9/l) has been identified as a poor prognostic factor in many cancers. Platelet-secreted factors may contribute to metastasis, invasion, and primary tumor growth. Methods. One hundred eighty-three patients with invasive epithelial ovarian or primary peritoneal carcinomas were identified between January 1996 and December 2000. Records were retrospectively reviewed and data analyzed using χ 2, Student's t test, and Cox proportional hazards model; survival was analyzed by the method of Kaplan and Meier. Results. Forty-one of 183 (22.4%) patients had thrombocytosis at primary diagnosis. Patients with preoperative thrombocytosis were found to have greater elevations of CA-125 ( P = 0.026), more advanced stage disease ( P = 0.016), higher grade tumors ( P = 0.010), more frequent lymph node metastases ( P = 0.018), and greater volume of ascites ( P < 0.0001). One hundred sixty of 183 (87.4%) patients achieved optimal cytoreduction; patients with thrombocytosis demonstrated a greater likelihood of suboptimal resection (residual disease >1 cm; 19/41 vs. 4/142 in patients without thrombocytosis, P < 0.0001). Patients with thrombocytosis had a shorter disease-free interval (12 vs. 34 months, P < 0.0001) and overall survival (28 vs. 79 months, P < 0.0001). On multivariate analysis, thrombocytosis retained significance as a poor prognostic indicator in patients with stage III and IVA disease ( P = 0.04). Conclusions. Thrombocytosis is a frequent preoperative finding in ovarian and peritoneal carcinomas and may be a marker of aggressive tumor biology.