Quantification of circulating tumour cells in patients with choroidal melanocytic tumours: correlation with clinical risk factors

Abstract

Purpose: Detect and quantify circulating tumour cells (CTCs) in peripheral blood of patients with choroidal melanocytic tumours and study the relationship of the CTCs with clinical risk factors.

Methods: Prospective study with three clinical groups: 4 patients diagnosed with choridal nevus, 8 patients with choroidal melanoma prior to treatment and 2 enucleated patients with metastases (liver) detected at 65 and 37 months after treatment. A single sample of 7.5 mL of peripheral blood was taken and the CTCs were isolated using a Celltrack system that captures positive cells for the CD146 antigen (MUC18).

Results: No patients with choroidal nevus had CTCs in peripheral blood. Of the 8 patients with choroidal melanoma prior to treatment, 50% had more than one CTC/7.5 mL. The higher level of CTCs cells in peripheral blood (3/7.5 mL) was detected in the patient with the larger choroidal melanoma which also presented extrascleral extension and epithelioid pathology. Furthermore, we were unable to detect any CTCs in those patients (n=2) with postenucleation liver metastases.

Conclusions: Performing an analysis with the Celltrack system allows to quantify the choroidal melanoma CTCs in peripheral blood. This finding highlights the potential usefulness of this technique to achieve the correct stratification and monitoring of the treatment.

Keywords: 589 melanoma • 744 tumors • 745 uvea