Cecal volvulus associated with carfilzomib use for al amyloidosis

Abstract

Introduction Proteasome inhibitors have emerged as quintessential therapies for light-chain (AL) amyloidosis and multiple myeloma in the last decade. While these agents are highly effective, reports have also documented toxicities affecting various organ systems. Whereas gastrointestinal (GI) toxicities are a relatively common occurrence with proteasome inhibitors, severe GI complications are exceedingly rare. Case Report We describe a unique case of a patient with AL amyloidosis who developed cecal volvulus after four weeks of treatment with carfilzomib. This severe GI manifestation has not been previously described in the literature. Management and Outcome The patient required right hemicolectomy. After clinical recovery, she restarted reduced-dose carfilzomib. She did not have any severe GI side effects following dose reduction, and continues with the current treatment regimen to the present day. Discussion/Conclusion The causality between volvulus and the treatment with carfilzomib was probable, with a documented score of 6 on the Naranjo probability nomogram. The exact mechanism behind this effect of carfilzomib has yet to be elucidated.