Endocrine Abstracts

Here we present a patient who had been on various anti-cancer medications such as tyrosine kinase inhibitors and checkpoint immune inhibitors. Eventually, anti-cancer therapy caused thyroid disfunction. Male, 74 years old, presented with fatigue, somnolence, decreased appetite, diarrhea and depression. His medications included tyrosine kinase inhibitor Axitinib (Inlyta) 5 mg which he has been taking for 1 year and human monoclonal antibody Denosumab (Exgeva) 120 mg since 2016. His family history had diabetes mellitus type 2. He has no family history of thyroid diseases. In 2012 while having routine checkup he was diagnosed with kidney cancer on the right side. He had partial right nephrectomy. However, recurrence occurred in 2015 and he had total right nephrectomy. In 2016 metastasis occurred in the right lung and bones. He was prescribed denosumab (Exgeva) and thyrosine kinase inhibitor pazopanib (Votrient) 800 mg. There was progression of the disease on the pazopanib and the patient had palliative radiation therapy in 2018 and in 2019. From October 2019 to June 2021 he had therapy with immune checkpoint inhibitor nivolumab (Opdivo) 480 mg. He started treatment with tyrosine kinase inhibitor Axitinib (Inlyta) 5 mg in November 2021 and the dose eventually was raised to 7 mg. During presenting the patient still continued taking the axitinib 5 mg. Thyroid ultrasound showed isthmus size 2 mm, right lobe volume 5 cm³, left lobe volume 11 cm³, no nodules presented. The gland had heterogeneous echotexture and normal vascularity. There was no pathology in lymph nodes. The evaluation of thyroid functional tests showed TSH 39.64 μIU/ml (reference 0.35-5.6 μIU/ml), free T4 11.55 pmol/l (reference 7-20 pmol/l), free T3 4.18 pmol/l (reference 3.10-6.80 pmol/l), fasting glucose 100 mg/dl, and HbA1c 5.6%. He undergone repeated laboratory checkup the 6 days after, on 29/09/2022 in another clinic and it showed TSH 34.54 uIU/ml (reference 0.35-5.6 uIU/ml), free T3 5.26 pmol/l (reference 3.1-6.8pmol/l), free T4 10.99 pmol/l (reference 7-20 pmol/l), Ab TPO 0.1 IU/ml (reference <9 IU/ml) and Ab Tg 1 IU/ml (reference 0-4.11 IU/ml). Therapy with levo-thyroxine (L-thyroxine) 25 mg/day was started immediately and gradually raised to 50 mg/day. Since then he is maintaining improvement in his symptoms. Following oncological whole-body 18 F-Fluorodeoxyglucose (FDG) PET/BT showed metastasis in lymph node in left supraclavicular area. Axitinib 5 mg was stopped and Cabozantinib (Cabometyx) 40 mg was prescribed.