Value of circulating tumor cell assessment to identify relapse risk

February 9, 2020

Abstract

Purpose: There is a need for sensitive, reproducible biomarkers for stage III melanoma patients to guide clinical decision making. Circulating tumor cells (CTCs) can be detected in melanoma patients; however, there is limited data regarding their significance in stage III disease. The aim of this study was to determine if CTCs are associated with early relapse in stage III melanoma.
Experimental Design: We prospectively assessed CTCs at first presentation in clinic (baseline) for 243 stage III melanoma patients. CTCs were measured using the CellSearch System. Relapse-free survival (RFS) was compared between patients with one or more baseline CTC versus those with no CTCs. Log-rank test and Cox regression analysis were applied to establish associations of CTCs with RFS.
Results: At least one baseline CTC was identified in 90/243 (37%) patients. Forty-five (19%), 67 (28%), 118 (49%), and 13 (5%) patients were stage IIIA, IIIB, IIIC, or IIID, respectively. CTC detection was not associated with sub stage, or primary tumor characteristics. Multivariable analysis demonstrated that the detection of ≥1 baseline CTC was significantly associated with decreased 6 month RFS (log-rank p <0.0001, hazard ratio (HR) 3.62, 95% confidence interval (CI) 1.78 to 7.36; P <0.0001) and 54 month RFS (log-rank p = 0.01, HR 1.69, CI 1.13 to 2.54; P = 0.01).
Conclusion: ≥1 CTC was independently associated with melanoma relapse, suggesting that CTC assessment may be useful to identify patients at risk for relapse who could derive benefit from adjuvant therapy.

Source:

Lucci, A., Hall, C., Patel, S. P., Narendran, B., Bauldry, J. B., Royal, R., … Ross, M. I. (2020). Circulating tumor cells and early relapse in node-positive melanoma. Clinical Cancer Research. doi: 10.1158/1078-0432.ccr-19-2670

https://clincancerres.aacrjournals.org/content/early/2020/02/01/1078-0432.CCR-19-2670