sodium-pertechnetate-tc-99m and Carcinoma--Medullary

A 61-year-old man with medullary thyroid carcinoma and local invasion of the left lobe of the thyroid had Tc-99m MIBI SPECT and Tl-201 chloride/Tc-99m pertechnetate subtraction SPECT after left lobectomy of the thyroid, using a triple-headed gamma camera. Tl-201 chloride/Tc-99m pertechnetate subtraction demonstrated a large mass with high Tl-201 uptake in the left neck. Although there was intense uptake in the tumor in the left thyroid bed on Tc-99m MIBI neck SPECT, there was also uptake in both salivary glands and the right lobe of the thyroid gland. Thus, uptake in the right lobe of the thyroid gland and the salivary glands might not be differentiated from tumor invasion or metastasis from medullary cell carcinoma. Compared with MIBI SPECT, Tl-201 chloride/Tc-99m pertechnetate subtraction SPECT shows more apparent delineation of tumor uptake and may be a preferable technique.

Topics: Carcinoma, Medullary; Humans; Male; Middle Aged; Neoplasm, Residual; Salivary Gland Neoplasms; Sodium Pertechnetate Tc 99m; Subtraction Technique; Technetium Tc 99m Sestamibi; Thallium; Thallium Radioisotopes; Thyroid Neoplasms; Tomography, Emission-Computed, Single-Photon

Thyroid gland scintigraphy was performed in 29 dogs with histologically confirmed thyroid tumors. Twenty dogs were female, and 9 were male. Median age was 10 years. Of the 29 dogs, 21 were initially examined because of cervical swelling or a cervical mass. Of the 29 tumors, 24 were thyroid adenocarcinomas, 1 was a C-cell carcinoma, 3 were undifferentiated carcinomas, and 1 was a thyroid adenoma. Serum triiodothyronine and thyroxine concentrations were determined in 25 dogs. Sixteen dogs were euthyroid, 6 were hyperthyroid, and 3 were hypothyroid. In all 29 dogs, results of scintigraphy were abnormal. The most common scintigraphic appearance (13 dogs) was a unilateral thyroid mass with increased radionuclide uptake, relative to that of the parotid salivary glands. There did not appear to be an association between distribution of radionuclide uptake and histologic diagnosis, although there appeared to be an association between distribution of uptake and histologic degree of capsular invasion. All 4 dogs with extensive capsular invasion and 11 of 17 dogs with limited capsular invasion had poorly circumscribed, heterogeneous uptake of pertechnetate by the tumor. All hyperthyroid dogs had intense uptake, and 5 of 6 hyperthyroid dogs had well-circumscribed, homogenous uptake. Scintigraphy did not appear to offer any additional benefit, compared with thoracic radiography, for detection of pulmonary metastases.

Topics: Adenocarcinoma; Adenoma; Animals; Carcinoma; Carcinoma, Medullary; Dog Diseases; Dogs; Female; Lung Neoplasms; Male; Radionuclide Imaging; Retrospective Studies; Sodium Pertechnetate Tc 99m; Thyroid Neoplasms; Thyroxine; Triiodothyronine