Patients with metastatic melanoma that have relapsed following immunotherapy may not respond as well to adoptive cell transfer of tumour-infiltrating lymphocytes (ACT-TIL) as those who have never received these treatments, a study shows.

With ACT-TIL, autologous tumour-infiltrating lymphocytes are taken from a patient’s tumour, grown in the laboratory, and then given back to the patient to help attack cancer cells.

Tumours exposed to prior treatments, including newer immunotherapies and targeted therapies, may yield fewer or less robust lymphocytes for the ACT-TIL to be effective.

“We noticed, over the last few years, we were seeing fewer responses to ACT-TIL in metastatic melanoma patients, which coincided with these newer therapies coming on board,” says study senior author Dr Stephanie Goff of the National Cancer Institute, in Bethesda, Maryland, US.