PDCD1 and melanoma: A vaccine activating melanoma-associated macrophages via AV-MEL-1, in combination with anti-PD-1, is currently recruiting patients (Hoag Hospital, Irvine, CA, USA) [134] and so is a new study aimed at developing imaging systems to detect M2 TAMs in metastases from melanoma (Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland) [135].