TPO and neoplasm: On admission, the thyroid panel revealed a normal thyroid function in terms of TSH (thyroid stimulating hormone) of 1.3 μIU/mL (normal range between 0.5 and 4.5 μIU/mL), FT4 (free levothyroxine) of 11.3 pmol/L (normal range between 9 and 19 pmol/L), negative serum thyroid antibodies, namely anti-thyroperoxidase antibodies of 0.65 IU/mL (normal range between 0 and 5.61 IU/mL), and normal serum tumour marker calcitonin of 0.84 pg/mL (normal range between 5.17 and 9.82 pg/mL).