Single, very low dose (0.03 mg) of recombinant human thyrotropin (rhTSH) effectively increases radioiodine uptake in the I-131 treatment of large nontoxic multinodular goiter.

BACKGROUND: Radioiodine therapy (RIT) in patients with large nontoxic multinodular goiter (MNG) recently becomes more common method in comparison to surgery (especially in elderly patients and with contraindications because of severe chronic diseases other systems). Repeatedly low thyroid radioactive iodine uptake (RAIU) decreases effectiveness of RIT or makes it impossible. The recombinant human thyrotropin can increase RAIU and improve the results of RIT. THE AIM OF THE STUDY: was to assess the influence of a single very low dose (0.03 mg) of rhTSH on RAIU and thyroid function in euthyroid (MNG-EU) and subclinical hyperthyroid (MNG-SC) patients with a large multinodular goiter. MATERIAL AND METHODS: 40 patients (14 male, 26 female, age 57-80 yr) with large non-toxic MNG over 80 grams and with baseline RAIU < 40% were included into the double-blind randomized study and divided into two groups: rhTSH-group and control group. First group received the single intramuscular injection of 0.03 mg rhTSH and the second received placebo. The RAIU were measured 24 and 48 hours after the rhTSH and then all the patients were administered therapeutic doses of I-131. TSH and free thyroxine levels were measured at 1st and 2nd day after the injection of rhTSH and later, at 4 and 8 weeks after the RIT. RESULTS: The mean RAIU increased significantly from 30.44 ± 7.4% to 77.22 ± 8.7% (p < 0.001). There were no statistically significant differences in RAIU between euthyroid (MNG-EU) and subclinically hyperthyroid (MNG-SC) patients. The peak of serum TSH was noticed 24 hours after rhTSH injection and in MNG-EU patients it has remained within normal range, similarly as fT4. In the MNG-SC group the administration of rhTSH resulted in a significant increase in the TSH values after 24 hours, whose mean level slightly exceeded the upper limit of the normal range with normalization at 48 hours. 8 weeks after the RIT, the TSH and fT4 levels did not exceed the normal range and did not differ in a statistically significant way. CONCLUSIONS: Even the single very low dose of rhTSH increases the values of RAIU in significant way, in euthyroid and subclinically hyperthyroid patients. The administration of rhTSH is well-tolerated. Neoadjuvant administration of a low dose (0.03 mg) of rhTSH before I-131 seems to be an optimal method of management which may increase the effectiveness of RIT and decrease the exposure of the patients to absorbed doses of ionizing radiation.

[Application scintigraphy in evaluation of salivary gland function]. / Zastosowanie scyntygrafii w badaniu funkcji gruczolów slinowych.

The salivary glands belong to the exocrine glands. There are tree main pairs of salivary glands: parotid, submandibular, sublingual. Several modalities are used for salivary gland imaging, such as sonography, computer tomography and magnetic resonance imaging. The aim of these methods is mainly to present morphological impairment. Parenchymal function and excretion function of all salivary glands can be quantified by scintigraphy. After single intravenous injection of 99mTc-pertechnetate sequential images are acquired up to 25-40 minutes. Usually about fifteen minutes postinjection 3 ml of lemon juice are administered intraorally as sialogogue. Salivary scintigraphy can estimate the severity of salivary gland involvement and function disorders, which may not be accurately reflected by the morphological damage. The clinical impact of scintigraphy has been reported in multiple salivary glands diseases, such as Sjogren's syndrome, sialolithiasis with or without parenchymal damage, iatrogenic irradiation of the salivary glands for therapy of head and neck tumors or radioiodine treatment of thyroid cancer. No other method can give so much information about function of salivary glands. Scintigraphy is noninvasive examination, easy to perform, reproducible and well-tolerated by the patient.

[The usefulness of nicotinamide in radioiodine therapy in patients with toxic and nontoxic large goitres]. / Uzytecznosc nikotnamidu w radiojodoterapii chorych z wolem nadczynny oraz dutymn wolem normoczynnym.

Nicotinamide (niacin) is very useful substance in treatment of many kinds of diseases. For the decades the main indications for application of niacin were lipid disorders. There are studies confirming that niacin increases thyroid radiosensitivity to 1-131. The radioiodine therapy is common method of treatment of hyperthyroidism (Graves' disease, toxic nodular goitre), large euthyroid goitre and differentiated thyroid cancer. In some studies with Wistar rats there is shown that niacin potentiates the effect of 1-131 by increasing thyroid blood flow, what results better effects of radioiodine treatment. Moreover niacin in therapeutic doses decreases serum thyroid hormone levels (mainly total thyroxine and thyroxine-binding globuline). In case of large goitre, when the calculated radioisotope dose exceeds ambulatory limits, the patient must be hospitalized. There are patients with low radioiodine uptake and radiosensitivity of thyroid, radiosensitizers can be utilized for this purpose. Recently obtained results of studies are showing that niacin can be used as radiosensitizer. It is making possible ambulatory treatment of patients with large goitres and low radioiodine sensitive thyroid. The radioiodine therapy with niacin could become shorter, less expensive and more safety for patients.