Immune cell activation may affect melanoma outcome

Brussels - Immune cells can be activated in the tumors of some patients with melanoma, potentially influencing clinical outcomes, new research indicates.

In many types of cancer, activated immune cells infiltrate the tumor and have an effect on outcome, but it is often unclear where these cells are activated, Newswise reports. A study from the Ludwig Institute for Cancer Research in Brussels suggests that in a subset of patients with metastatic melanoma, immune cells can be activated in the tumor microenvironment.

In some instances of chronic infection, ectopic lymphoids form at the site of the infection and locally support lymphocyte responses against the infection. In some studies, ectopic lymphoids’ presence has been linked to improved prognosis.

Study investigators observed ectopic lymphoid structures in seven out of 29 skin metastases from patients with melanoma. In contrast, no primary melanoma samples examined contained complete ectopic lymphoid structures. Some of them, however, hosted small blood vessels associated with these structures. Further analyses indicated that the ectopic lymphoid structures were functional, as features indicative of activation of the B cell lymphocyte subset were observed.

“It is important to have established that immune responses can be generated locally, at least in skin metastases,” Newswise quotes study authors as saying. “In fact, this last point, that we detected functional lymphoid structures in skin metastases and not in primary tumors, is extremely intriguing. We think that understanding the reasons for this difference will be highly informative in determining how antimelanoma immune responses develop during disease progression.”

The sample size was too small to allow researchers to draw clinically meaningful conclusions, Newswise reports. The study was published in Cancer Research.

Go back to the Dermatology Times eNews newsletter.