Mary Jo Lawyer Spano Mesothelioma Patient Registry Act of 2021 This bill requires the Agency for Toxic Substances and Disease Registry, which is part of the Department of Health and Human Services, to establish a mesothelioma patient registry. (Mesothelioma is a cancer of the tissue lining the lung, chest, and abdomen areas and is generally associated with asbestos exposure.) The registry must include information relating to the incidence and prevalence of mesothelioma in the United States, including treatment outcomes and demographics.