Esophagitis as a complication of the combination of lenvatinib and pembrolizumab for advanced endometrial cancer: A case report.

BACKGROUND: Pembrolizumab is a monoclonal antibody targeting the programmed cell death protein 1 (PD-1). It is used in the management and treatment of various oncologic conditions. To name a few: refractory and advanced melanoma, non-small cell lung cancer (NSCLC), head and neck squamous cell carcinoma (HNSCC), renal cell carcinoma and gastric cancer. It is also approved for metastatic mismatch repair deficient (dMMR) endometrial carcinoma after failure of front-line chemotherapy. Lenvatinib is an oral multikinase inhibitor that targets vascular endothelial growth factor receptors 1-3, fibroblast growth factor receptors 1-4, platelet-derived growth factor receptor-a, RET, and KIT. The combination of lenvatinib and pembrolizumab has proven to be more effective together than as monotherapy. Here, we present the case of a patient who probably developed lenvatinib-related esophagitis, a complication not previously described in the literature to our knowledge.Case presentation.We describe a 65 years old female with metastatic endometrial cancer who presented dysphagia after a few months of lenvatinib plus pembrolizumab treatment. Upper endoscopy results revealed a very fragile upper esophageal mucosa with mucosal lacerations, consistent with grade 2 esophagitis. The biopsy showed esophagitis with mixed lymphocytic and eosinophilic inflammation and apoptotic component. Pembrolizumab was then stopped pending the results of the biopsy, following the recommendations of the gastroenterologist. Dysphagia, however, remained unchanged. In the meantime, the lenvatinib had to be stopped due to a dental procedure, and the patient noted a marked improvement in her symptoms. After discussion with the gastroenterologist, pembrolizumab was resumed and lenvatinib was suspended. The patient was also started on a PPI twice daily since the first digestive exploration. 1 month later, upper endoscopy showed complete recovery, the patient's symptoms improved, and lenvatinib was resumed. However, symptoms of dysphagia resumed a few days later. Lenvatinib was finally resumed at a reduced dose without reappearance in her symptoms.

CONCLUSIONS: We present a case of oesophagitis as a likely complication of lenvatinib for advanced endometrial cancer. The initiation of PPI and dose reduction of the lenvatinib allowed the patient to successfully go back on treatment.