Circulating tumor cells (CTC) in newly diagnosed breast or colorectal cancers

Abstract

14512 Background: The presence of CTCs is associated with poor prognosis in patients with metastatic carcinomas. The significance of CTCs at the time of diagnosis and after therapy is not known. A prospective clinical trial is conducted to determine if monitoring CTC levels in pts diagnosed with breast and colorectal cancer identify pts at risk for recurrence. CTCs are correlated with pathological stage as follow-up is too short to assess recurrence risk. Methods: Currently 213 pts with newly diagnosed breast and 119 pts with colorectal cancer before surgery with curative intend have been enrolled as well as a control group of 120 patients in whom diagnosis of breast or colorectal cancer was excluded. Thirty ml of blood was screened for the presence of CTCs at baseline before surgery and every following year using the CellSearch™ System. Results: Presence of CTCs in 30mL of blood in breast, colorectal cancer and the control group is provided in the table . In colorectal cancer the average number of CTCs /30 mL at baseline for Dukes A, B and C was 0.2, 0.7 and 1.1 respectively, for stage 0, I, II, III breast cancer 0.3, 0.5, 0.6 and 1.8 respectively and for the control group 0.24 CTCs /30 mL. Conclusions: CTC can be detected in a substantial proportion of pts before and after definitive surgery for breast and colorectal cancer. The number of CTCs before surgery correlated with the stage of the disease. Specificity of the CellSearch™ System is being increased to improve the discrimination of patients with benign and malignant disease. Follow-up must clarify whether the presence CTCs is an identifier for the risk of recurrence. [Table: see text] No significant financial relationships to disclose.