Lenvatinib in combination with pembrolizumab in heavily pretreated metastatic thymic carcinoma: A case report

Thymoma and thymic carcinomas are rare tumors with limited therapeutic options for platinum-refractory cases. Recent studies have shown positive response rates in anti-angiogenic multi-kinase inhibitors (MKI) such as lenvatinib and sunitinib and immune checkpoint inhibitors including pembrolizumab, though they have yet to be tested in combination. Here, we present a case of a patient with heavily pre-treated PD-L1 negative metastatic thymic carcinoma and no targetable mutations treated with combination lenvatinib and pembrolizumab following initial response then progression from lenvatinib monotherapy. He had a partial response with decreased tumor burden in the liver with lenvatinib monotherapy and then in the lungs with combination therapy. Treatment was continued and he continues have clinical benefit with stable disease at 9 months with minimal toxicities. This case is one of the first reported clinical evidence for MKI and immunotherapy in combination as a promising second-line approach for thymic carcinomas.