Whitaker JA, Shanafelt TD, Poland GA, Kay NE. Room for improvement: immunizations for patients with monoclonal B -cell lymphocytosis or c hronic lymphocytic leukemia. Clin Adv Hematol Oncol. 2014;12:440 -450. 36. Oosting SF, van der Veldt AAM, GeurtsvanKessel CH, et al. mRNA -1273 COVID -19 vaccination in patients receiving chemotherapy, immunotherapy, or chemoimmunotherapy for solid tumours: a pr ospective, multicentre, non -inferiority trial. Lancet Oncol. 2021;22:1681 -1691. 37. Crooke SN, Ovsyannikova IG, Poland GA, Kennedy RB. Immunosenescence and human vaccine immune responses. Immun Ageing . 2019;16:25.