The Phase II NEO-DVIC trial (NCT04201873) compared the efficacy of conventional neoadjuvant chemotherapy with the cDC1 vaccine in combination with pablizumab in patients with primary osteosarcoma: The primary pathological response rate (MPR) of 56% in the cDC1 vaccine group (n = 25) was significantly higher than that of 20% in the chemotherapy group. This evidence concerns the gene MPPE1 and osteosarcoma.