Lenvatinib-Induced Acalculous Cholecystitis-An Often-Unrecognized Toxicity: A Case Series and Literature Review.

Lenvatinib is an oral multi-kinase inhibitor which is used for the treatment of renal cell carcinoma, non-iodine avid differentiated thyroid cancer, hepatocellular carcinoma, and endometrial cancer. We present a series of three (3) patients who, whilst on treatment with Lenvatinib, developed symptoms and radiological findings of acalculous cholecystitis. A radiological review of another nineteen (19) Lenvatinib-treated patients in our center was undertaken, with another three (3) patients exhibiting radiological features of acalculous cholecystitis with gallbladder wall thickening and pericholecystic fluid collection but without abdominal pain or clinical symptoms of cholecystitis. A literature review is also presented of all previous publications of Lenvatinib-induced acalculous cholecystitis, including the results of two pharmacovigilance studies. This review provides evidence that Lenvatinib-induced acalculous cholecystitis is not as rare as initially thought from the Lenvatinib licensing studies; hence, this is an adverse event that merits more attention. Oncologists using Lenvatinib should be aware of this potential toxicity and be familiar with its management.