A case of hypothyroid Graves' disease following external radiation therapy to the cervical region.
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.
Nishihara
Eijun
E
Kuma Hospital, Kobe, Japan.
Fukata
Shuji
S
Kimura
Nobuhiko
N
Hagihara
Masahiro
M
Kudo
Takumi
T
Ohye
Hidemi
H
Ito
Mitsuru
M
Kubota
Sumihisa
S
Amino
Nobuyuki
N
Kuma
Kanji
K
Miyauchi
Akira
A
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