Intrathoracic papillary thyroid carcinoma from occult primary disease.

A 42-year-old woman undertook a chest radiograph for a routine evaluation prior to surgery for pelvic endometrioma, which revealed a right paratracheal mass slightly displacing the trachea to the left. CT of the thorax disclosed a well demarcated, heterogeneous, lobular, right paratracheal mass, bearing punctate, coarse, and curvilinear calcifications. MRI further revealed two components within the lesion: a larger, cystic, exhibiting thin septations, and a solid component at the lower part exhibiting strong enhancement. No continuity of the mass with the thyroid gland was demonstrated, which had normal size and no focal lesion. Histological examination of the resected mass disclosed lymph node tissue infiltrated by papillary thyroid carcinoma; subsequent total thyroidectomy revealed small foci of papillary carcinoma within both lobes of the thyroid gland. Ablative dose I-131 was administered and the patient was put on daily thyroid supplements.