The authors report a case of abnormal accumulation of I-131 in a thoracic vertebra in a patient with a well-differentiated thyroid carcinoma. The presumptive diagnosis was metastatic bone disease. Further diagnostic work-up confirmed a benign bone lesion. Bone metastasis, when shown on I-131 whole-body scintigraphy, usually supports a change in the staging and therapeutic approach to a patient with thyroid carcinoma. The authors believe that, although an infrequent lesion, the differential diagnosis of abnormal accumulation of I-131 in the body of a vertebra in patients with well-differentiated thyroid carcinoma should raise the possibility of a benign hemangioma. Complete work-up of the suggested bone metastatic lesion should be performed before tumor restaging and I-131 therapy is recommended.

Ectopic thyroid tissue is a rare clinical entity wherein malignant lesions may arise, the most common one being papillary carcinoma. We present a case of a 68-year-old female who presented with a growing mass in the right clavicle. An MR of the shoulder showed a soft tissue mass arising from the anterior margin of the right distal clavicle. A fine needle aspiration of the mass showed papillary thyroid carcinoma. PET/CT confirmed the clavicular and mediastinal mass. Excision of the clavicular mass and total thyroidectomy with modified right neck dissection were performed. Pathology revealed no evidence of malignancy in the thyroid; lymph nodes were positive for metastatic thyroid carcinoma. Postsurgery CT showed the superior mediastinal mass with surrounding adenopathy; radioiodine (RAI) treatment with dose of 142.1 mCi [5257.7 MBq] was recommended. Posttherapy whole-body scan (WBS) showed RAI avid tissue in the neck and superior mediastinum. Follow-up chest CT revealed pulmonary nodules that increased in number and size; a second RAI therapeutic dose was given. The posttherapy RAI WBS was negative. Repeat PET/CT showed multiple hypermetabolic lesions in the mediastinum, neck, lymph nodes, pulmonary nodes, and right shoulder. The FDG avid lesions with no RAI uptake suggested tumor dedifferentiation.

The purpose of this study was to describe the characteristics of well differentiated thyroid carcinoma (WTC) in Hispanic children and analyze treatment response. Retrospective evaluation of records seen at our institution from 1970-2007 was undertaken. Twenty-seven cases were evaluated, 24 were treated with radioiodine, followed for a mean period of 15 years. There were 18 females, 9 males, median age 11 years. Eleven tumors were papillary', IS papillary-follicular variant and one follicular. All had total thyroidectomy and iodine scan. Initially 75% of the tumors were T2, 79% were Nl, and 29% had distant mctastases. Radioiodine was given to 89%. The cumulative radiation dose ranged from 110-925 mCi. Residual disease was present in 25% at last follow up, maximal follow up 37 years without tumor recurrence. Patients were all alive, 75% were disease-free. WTC in pediatrics is extensive at diagnosis; treatment outcome and longterm survival are excellent.

Primary thymic carcinoids are rare tumors in which the tumor cells retain functional somatostatin receptors. In-111-labeled octreotide imaging has been used to diagnose abdominal carcinoids with a sensitivity rate of approximately 87%. The authors describe a case of a recurrent, ectopic cortisol-releasing hormone that produced thymic carcinoid localized as a focal area of increased activity in the upper mediastinum when planar and tomographic octreotide scintigraphy was used. Chest CT and MRI failed to localize the tumor. This may be the first reported case of In-111-labeled octreotide used to identify Cushing's syndrome caused by a cortisol-releasing hormone that produced thymic carcinoid.

No abstract