title: Differentiated thyroid cancer presenting with thyrotoxicosis due to functioning metastases.
abstract: Thyrotoxicosis due to functioning metastases in differentiated thyroid cancer (DTC) is exceedingly rare. We report a case of follicular carcinoma in a 54-year-old manager, who presented with thyrotoxicosis, shortness of breath and lung metastases. Transbronchial biopsy of a pulmonary nodule demonstrated normal thyroid. This was interpreted as representing very well-differentiated thyroid cancer. CT, (131)I whole-body imaging and dosimetry is described following total thyroidectomy and repeated radioiodine administration (cumulative activity 34.6 GBq). The patient became asymptomatic with almost complete eradication of the pulmonary metastases. Potential complications of thyroid storm, bone marrow failure and pulmonary fibrosis following radioiodine are discussed, together with methods to minimise these risks.
authors.affiliation: Thyroid Unit, Royal Marsden Hospital, Surrey, London, UK. masudhaq@hotmail.com
authors.forename: M
authors.initials: M
authors.lastname: Haq
authors.forename: S
authors.initials: S
authors.lastname: Hyer
authors.forename: G
authors.initials: G
authors.lastname: Flux
authors.forename: G
authors.initials: G
authors.lastname: Cook
authors.forename: C
authors.initials: C
authors.lastname: Harmer
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000000981:diagnostic imaging / Q000532:radiotherapy / Q000556:secondary*; D004417:Dyspnea / Q000209:etiology; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D013964:Thyroid Neoplasms / Q000532:radiotherapy* / Q000601:surgery; D013965:Thyroidectomy; D013971:Thyrotoxicosis / Q000209:etiology*; D014057:Tomography, X-Ray Computed
chemical_list: D007457:Iodine Radioisotopes