Supplementary Material for: De-escalated adjuvant treatment for advanced MMR deficient mixed endometrioid/ clear cell endometrial carcinoma with PD-1 inhibition alone – a case report

Advanced mixed epithelial endometrial carcinomas are rare high-grade cancers with a poor prognosis. A clear cell component infers relative chemotherapy insensitivity, likely further increased by p53 wild type status and MMR deficiency. PD-1 inhibition for MMR deficient endometrial cancers has been recently added to first-line adjuvant treatment in combination with platinum-based chemotherapy. Information on de-escalation of adjuvant treatment to PD-1 inhibition alone without chemotherapy is sparse. Here, we present a patient with advanced stage mixed epithelial endometrial carcinoma, a clear cell component and MMR deficiency who underwent de-escalated adjuvant treatment with PD-1 inhibition alone without simultaneous chemotherapy.