title: A case of hypothyroid Graves' disease following external radiation therapy to the cervical region.
abstract: A case of hypothyroid Graves' disease occurred following external radiation therapy to the cervical region is described. Severe hypothyroidism developed in a 56-year-old man 6 months after external radiation therapy for submandibular cancer. Serological evaluation of thyroid autoimmunity revealed the presence of antithyroid antibodies and thyrotropin-binding inhibitory immunogloblins (TBII). Diplopia, limitation of downward gaze, and palpebral edema developed 2 years after levothyroxine replacement therapy. Ocular magnetic resonance imaging revealed marked hypertrophy of the bilateral extraocular muscles with signal hyperintensity on T2-weighted images. This infiltrative ophthalmopathy showed marked improvement after additional treatment with high-dose methylprednisolone and orbital radiation, in parallel with a decrease in TBII. These results suggest that radiation-associated thyroidal injury might be associated with the etiology of hypothyroid Graves' disease.
authors.affiliation: Kuma Hospital, Kobe, Japan.
authors.forename: Eijun
authors.initials: E
authors.lastname: Nishihara
authors.forename: Shuji
authors.initials: S
authors.lastname: Fukata
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Kimura
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hagihara
authors.forename: Takumi
authors.initials: T
authors.lastname: Kudo
authors.forename: Hidemi
authors.initials: H
authors.lastname: Ohye
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Ito
authors.forename: Sumihisa
authors.initials: S
authors.lastname: Kubota
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Amino
authors.forename: Kanji
authors.initials: K
authors.lastname: Kuma
authors.forename: Akira
authors.initials: A
authors.lastname: Miyauchi
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy; D004172:Diplopia / Q000000981:diagnostic imaging / Q000209:etiology; D006111:Graves Disease / Q000175:diagnosis* / Q000209:etiology*; D049970:Graves Ophthalmopathy / Q000209:etiology; D006801:Humans; D007037:Hypothyroidism / Q000175:diagnosis* / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D011832:Radiation Injuries / Q000209:etiology*; D011878:Radiotherapy / Q000009:adverse effects*; D013365:Submandibular Gland Neoplasms / Q000532:radiotherapy*; D014463:Ultrasonography