Circulating Tumour Cells Associated With Relapse in Late-Stage Melanoma

A study revealing a connection between circulating tumour cells (CTCs) and relapse in patients with stage IV melanoma points to liquid biopsy as a potential predictor of patients at high risk for disease progression.

Findings from the study, led by Anthony Lucci, MD, University of Texas M. D. Anderson Center, Houston, Texas, were presented today at the Annual Meeting of the Western Surgical Association.

Based on earlier studies in which Dr. Lucci found significant levels of CTCS in breast cancer, he theorised that CTCs may also be present in patients with melanoma.

"Optimal management of patients with stage IV melanoma remains a challenge, since in spite of promising emerging therapies, many patients develop disease resistance," said Dr. Lucci. "This study, designed to determine if CTCs are associated with relapse, detected CTCs in approximately 40% of patients with advanced melanoma."

The team conducted a CTC assessment through blood drawn from 93 patients with melanoma at the time of stage IV diagnosis. Median follow-up was 17 months and the mean patient age was 55 years.

CTCs were detected in 42% of patients at the time of blood draw. Of the 93 patients, 57 (61%) experienced disease relapse. The study showed that, within 6 months, 51% of patients who had tested positive for CTCs experienced relapse, while disease recurred in 15% of patients without CTCs. Over the 5-year follow-up period, 82% of those patients who had tested positive for CTCs experienced relapse, while 46% of those who did not have CTCs had disease recurrence.

"Based on our findings, it is clear that patients with stage IV melanoma with CTCs have a significantly higher chance of relapsing or progressing as compared with those without CTCs," said Dr. Lucci. "Hopefully, in the future this information could be used to guide treatment, or select patients for treatment -- or maybe stop a treatment and switch to another -- when it appears it is not working."

Dr. Lucci previously led the first study of CTCs in early-stage breast cancer, which followed 302 patients with non-metastatic breast cancer. They discovered that CTCs were present in 24% of patients with stage I, II or 3 breast cancer, demonstrating CTCs as an independent predictor of worse, disease free, and overall survival. The results were published in The Lancet Oncology in 2012.

SOURCE: University of Texas M. D. Anderson Cancer Center