CD248 and telomere syndrome: The immunoconjugates being investigated in STS patients, such as antibody drug conjugates (ADCs), immunotoxins, and radioimmunoconjugates, are directed to a variety of cell surface antigens including endosialin (CD248), EGFR, CSPG4, NCAM, GPNMB, uPARAP, ROR2, CD70, and FZD10 [15].