Rare case of wtTTR amyloidosis and MGUS in a patient with lung adenocarcinoma

Amyloidosis is a rare, multisystem disease that leads to deposition of misfolded proteins in various organs. This case report presents a patient with cancer with a rare diagnosis of diffuse alveolar-septal transthyretin (TTR) amyloidosis with subsequent protein electrophoresis identifying monoclonal gammopathy of unknown significance. It highlights the association of amyloidosis with malignancy and the importance of including workup for plasma cell dyscrasias in patients found to have TTR amyloidosis. There are major differences in the clinical course and treatment of amyloid light chain and amyloid transthyretin amyloidosis, and evaluation of the precursor protein(s) is critical as a guide for management.