Anaplastic thyroid carcinoma transformation in a patient with advanced non-small cell lung cancer treated with PD-1 therapy: A case report

Abstract

There have rarely been reports on the neoplastic transformation in other organs during immunotherapy for lung cancer. We report the case of a 71-year-old man who was diagnosed with advanced pulmonary adenocarcinoma and a thyroid tumor. The patient responded to chemoradiotherapy but developed a recurrence of pulmonary metastasis. Therefore, nivolumab was started, and a complete response for pulmonary metastasis was achieved. After 32 nivolumab cycles, he experienced neck pain, and the thyroid tumor grew rapidly. Histological examination revealed anaplastic thyroid carcinoma. Although rare, immunotherapy for lung cancer has the potential to induce neoplastic transformation in other organs.