technetium-tc-99m-medronate and Neurilemmoma

Topics: Adult; Bone Neoplasms; Diagnosis, Differential; Female; Humans; Ilium; Myositis Ossificans; Neurilemmoma; Radionuclide Imaging; Radiopharmaceuticals; Technetium Tc 99m Medronate; Tomography, X-Ray Computed

Topics: Aged; Breast Neoplasms; Diagnosis, Differential; Female; Femoral Neoplasms; Humans; Neurilemmoma; Peripheral Nervous System Neoplasms; Radionuclide Imaging; Sciatic Nerve; Technetium Tc 99m Medronate

I-131 whole-body imaging may show characteristic findings in functioning, metastatic differentiated thyroid carcinoma. Nonthyroidal tumor uptake of I-131 is rare, but may mislead the physician to inappropriate treatment. A case is reported of a 59-year-old woman with papillary thyroid carcinoma who demonstrated strong uptake of I-131 in an abdominal cystic neurilemoma. Her serum thyroglobulin concentration at that time was low, at 3.35 ng/ml. Although the concentrating mechanism of I-131 was not clear, several clues pointed to the possibilities of nonthyroidal tumor uptake: 1) faster clearing of radioactivity than usual thyroid tissue, 2) persistent low serum thyroglobulin concentration, and 3) the presence of a cystic component in the nonthyroidal tumor.

Topics: Abdominal Neoplasms; Carcinoma, Papillary; Diagnosis, Differential; False Positive Reactions; Female; Humans; Iodine Radioisotopes; Middle Aged; Neoplasms, Second Primary; Neurilemmoma; Radionuclide Imaging; Technetium Tc 99m Medronate; Thyroglobulin; Thyroid Neoplasms

Topics: Diagnosis, Differential; Female; Femoral Neoplasms; Humans; Middle Aged; Neurilemmoma; Neurofibroma; Radionuclide Imaging; Technetium Tc 99m Medronate