Iodine-125 radioactive particles antagonize hyperprogressive disease following immunotherapy

Rationale: Increasing evidence has shown that immune checkpoint inhibitors are associated with hyperprogressive disease (HPD). HPD usually resulted in dramatically reduced survival duration, which limited the opportunity to administer other therapies. Patient concerns: A heavily pretreated lung adenocarcinoma patient experienced rapid progression of rib metastasis soon after immune checkpoint inhibitor -based combination therapy. Diagnoses: On the basis of radiographic and pathological findings, the patient was diagnosed with HPD. Interventions: We treated the patient with iodine-125 radioactive particle implantation to the metastatic lesions in the chest wall. Outcomes: The metastatic lesions shrank significantly 1 month later. Lessons: Early detection and adequate treatment are essential for prolonged survival when HPD occurs.