P49-5 Tyrosine kinase inhibitor-induced thyroid dysfunction in the era of precision cancer therapy

Tyrosine kinase inhibitors (TKIs) are molecular targeted therapies used in the treatment of various malignancies. Thyroid dysfunction is an increasingly recognized adverse effect TKIs. We report a case TKI-associated thyroid patient with advanced lung cancer. A 61-year-old woman, Eastern Cooperative Oncology Group (ECOG) performance status 0, presented 5-month history cough. CT scan demonstrated 7.3 cm left mass abutting posterior mediastinum and encasing main bronchus. An FDG-positron emission tomography/computed tomography (FDG-PET/CT) showed extensive nodal metastases. core biopsy was performed. She diagnosed stage IV anaplastic lymphoma (ALK)-positive non-small cell adenocarcinoma commenced on alectinib. After 6 months alectinib, which she tolerated well, progress revealed significant primary tumor size reduction. Pre-alectinib function normal, her regularly monitored during treatment. 12 after starting elevated stimulating hormone (TSH) level noted (TSH 12.63 mIU/L, range: 0.27 - 4.2 mIU/L), normal free T4 T3 levels, keeping subclinical hypothyroidism. Thyroglobulin antibodies peroxidase were not detected. asymptomatic clinically euthyroid examination. There no goiter or palpable nodule. replacement indicated. Repeat tests weeks later improved function, TSH 5.02 mIU/L levels. autoantibodies remained undetectable. Her continues to be closely. Clinicians should vigilant for dysfunction. Regular monitoring important patients treated