sodium-pertechnetate-tc-99m and Pituitary-Neoplasms

To present two cases with thyrotropin-secreting adenoma and the effectiveness of octreotide acetate treatment on their tumor size as well as on thyroid stimulating hormone (TSH) and thyroid hormone levels.. The first case presented with tremor, palpitations and sweating as suggestive of hyperthyroidism, but the other one presented with predominantly headache, while the other symptoms such as palpitation and nervousness were less prominent and he also did not have any thyroid enlargement at physical examination. Thyroid hormone levels in both cases were increased. However, TSH levels were not suppressed thus indicating an inappropriate secretion of TSH. Moreover, TSH levels did not change after T3 and TRH administration, which also contributed to the assumption of an inappropriate TSH secretion. One case had no increase in the TSH alpha subunit level, while this was increased in the other one. Both magnetic resonance imaging and somatostatin receptor scintigraphy revealed that there was a microadenoma (the first case; 6 x 7 mm in diameter)and a macroadenoma (the second case; 14 x 18 mm in diameter). Both patients were placed on a therapy with somatostatin analog octreotide (Sandostatin, Sandoz). Octreotide was initially given at a dose of 300 microg daily and then increased gradually up to 600 microg per day. There was some decrease in the levels of TSH and thyroid hormones at first. However, such decreases did not persist with ongoing therapy for 6 months. In addition, there was no change in the tumor size with this therapy at the end.. We conclude that the treatment by somatostatin analogue octreotide may not be an effective means of reducing the pituitary tumor size, though it may be used to reduce TSH and thyroid hormones temporarily.

Topics: Adenoma; Adult; Antineoplastic Agents, Hormonal; Humans; Magnetic Resonance Imaging; Male; Octreotide; Pituitary Neoplasms; Sodium Pertechnetate Tc 99m; Thyrotropin; Ultrasonography

Topics: Adenoma; Female; Follow-Up Studies; Humans; Middle Aged; Pituitary Neoplasms; Radionuclide Imaging; Radiopharmaceuticals; Sodium Pertechnetate Tc 99m; Thyrotropin; Treatment Outcome

Topics: Adenoma; Aged; Empty Sella Syndrome; Female; Humans; Indium Radioisotopes; Magnetic Resonance Imaging; Octreotide; Pentetic Acid; Pituitary Neoplasms; Radiopharmaceuticals; Receptors, Dopamine D2; Receptors, Somatostatin; Sodium Pertechnetate Tc 99m; Thyrotropin; Tomography, Emission-Computed, Single-Photon

A 27-year-old woman who presented with a left thyroid nodule was found to have hyperthyroidism caused by a syndrome of inappropriate secretion of TSH. The levels of free T3, free T4 and TSH were 9.50 pg/mL, 4.05 ng/dL and 2.16 microU/mL, respectively. Magnetic resonance imaging of the head revealed a pituitary macroadenoma. The TSH response to TRH stimulation was normal and responses of other anterior pituitary hormones to stimulation tests were also normally preserved. Administration of octreotide with iodine successfully reversed hyperthyroidism prior to total resection of pituitary adenoma, which was followed by hemithyroidectomy of the left thyroid five months later. Histologically, the resected pituitary adenoma was a TSH-producing adenoma (TSH-oma) and the thyroid nodule was a papillary adenocarcinoma. Serum TSH diminished to undetectable levels immediately following pituitary adenomectomy but gradually normalized over nine months. Coexistence of a TSH-oma with thyroid cancer is very rare and only two similar cases have previously been documented. This combination raises the possibility that TSH may be involved in tumorigenesis in the thyroid gland.

Topics: Adenocarcinoma, Papillary; Adenoma; Adult; Biopsy, Needle; Female; Humans; Hyperthyroidism; Iodine; Iodine Radioisotopes; Lymphatic Metastasis; Magnetic Resonance Imaging; Neoplasms, Multiple Primary; Octreotide; Pituitary Neoplasms; Sodium Pertechnetate Tc 99m; Thyroid Neoplasms; Thyroidectomy; Thyrotropin; Thyrotropin-Releasing Hormone; Ultrasonography

After the intravenous administration of a radiolabeled somatostatin analogue (octreotide), normal thyroid and neoplastic and nonneoplastic thyroid lesions can be visualized. The authors present the cases of two patients who underwent somatostatin receptor scintigraphy (SSRS) using In-111 pentetreotide: one for the study of suspected paraneoplastic ACTH hypersecretion, and the other for a restaging of breast carcinoma with neuroendocrine features. In both patients, SSRS revealed increased uptake in the thyroid, corresponding to "cold" nodules on Tc-99m pertechnetate imaging. Cytologic and histologic examinations showed the typical features of thyroid goiters without lymphocytic infiltration.

Topics: Adenoma; Adrenocorticotropic Hormone; Biopsy, Needle; Breast Neoplasms; Carcinoma; Female; Goiter, Nodular; Humans; Indium Radioisotopes; Injections, Intravenous; Middle Aged; Neoplasm Staging; Neuroendocrine Tumors; Paraneoplastic Syndromes; Pituitary Neoplasms; Radionuclide Imaging; Radiopharmaceuticals; Receptors, Somatostatin; Sodium Pertechnetate Tc 99m; Somatostatin; Thyroid Gland; Thyroid Nodule