The correlation between a 131I whole-body scan (WBS), a 99mTc sestamibi (99mTc-MIBI) WBS, a computed tomography (CT) scan and the value of routine follow-up for 131I WBS and thyroglobulin (Tg) levels in patients with lung metastases from differentiated thyroid cancer was assessed. Pulmonary metastases were detected in 32 patients out of 583 with differentiated thyroid cancer (DTC) who were admitted to our clinic between 1985 and 2004 (age range, 22-79 years; mean, 58 +/- 19 years; 15 women and 17 men). Pulmonary metastases were diagnosed by considering the 131I WBS, increased Tg levels and/or other positive radiological findings. Papillary carcinoma was diagnosed in 15/32 patients and follicular carcinoma in 13/32. A mixed type found in 4/32 patients was classified histopathologically. A total of 3.7-53.65 GBq (100-1450 mCi) 131I was given to each patient. The duration of follow-up ranged from 36 to 240 months. A 131I WBS, the determination of Tg levels and/or a CT scan were carried out in the assessment of a diagnosis and follow-up of patients with lung metastases. A 99mTc-MIBI WBS was performed on 19 patients who were chosen at random from the 583. Nineteen of 32 patients had lung metastases before they received the first 131I treatment. Six of the 32 had distant-organ metastases other than in the lungs. Four of these six patients had only lung and bone metastases. Pulmonary metastases were observed on the 131I WBS patients 31/32 (96.8%) whereas no pulmonary metastases, were detected on the CT scans in 3/32 patients. The last diagnostic whole-body scan (DWBS) was normal in 13/32 patients. At the first examination, the Tg levels in 27/32 (84.4%) patients were below 30 ng . ml(-1). At the final examination, 20/32 (62.5%) patients had Tg levels higher than 30 ng . ml(-1), while Tg levels were lower than 30 ng . ml(-1) in 12/32 patients. Tg levels decreased in 21/32 and increased in 3/32 patients. The 131I WBS continued to be abnormal in 2/3 patients with increased Tg levels but became normal in one patient whose CT scan still showed macro-nodular lesions. Tg levels did not change significantly in 8/32 patients. The 131I WBS became normal in 5/8 patients, while the CT scans for 4/5 showed micro-nodules. Metastases were detected in 12/19 patients who underwent 99mTc-MIBI whole-body scanning: 18/19 showed metastases on the 131I WBSs and 17/19 on the CT scans. Of the seven patients without a sign of metastasis on the 99mTc-MIBI WBS, one was negative in terms of metastasis on the 131I WBS and one on the CT scan. Fibrosis was observed on the CT scans of 2/32 patients. One patient developed dedifferentiation, as determined by the negative 131I WBS and positive CT scan. 131I whole-body scanning and the determination of Tg levels are the most important procedures for the evaluation of lung metastases in differentiated thyroid cancer. Computed tomography is a useful addition to 131I whole-body scanning. MIBI imaging alone may not be enough to detect lung metastases from differentiated thyroid cancer.

Aim This study was designed to evaluate the efficiency of montelukast as a novel radioprotective agent against sodium [¹³¹I]iodide or potassium [¹³¹I]iodide (¹³¹I)-induced salivary gland damage in a rat model. Materials and methods The function and structure of salivary glands in 50 albino Wistar rats were evaluated with technetium-99m pertechnetate scintigraphies and histopathological examination. The animals were classified into five groups as follows: the control group (sham operated); group 1 (n=10; only ¹³¹I administration), group 2 (n=10; administration with ¹³¹I and montelukast); group 3 (n=10; ¹³¹I administration after total thyroidectomy); and group 4 (n=10; administration with ¹³¹I and montelukast after total thyroidectomy). All rats were killed at the end of the third month and three pairs of salivary glands were removed surgically. Results The scintigraphic evaluation revealed better results for groups administered montelukast than it did for other groups. Statistically significant differences (P<0.05 or P0.05) between groups 1 and 2 (n=20) and groups 3 and 4 (n=20). Histopathological examinations showed that pathological changes were significantly high in the groups treated with ¹³¹I without montelukast when compared with the other groups. Conclusion This is the first study on rats to assess the protective effect of montelukast on salivary glands after ¹³¹I therapy. According to our results, montelukast was found to be a potential protective agent against ¹³¹I-induced damage on salivary glands.

Background: To analyze protective/regenerative effects of adipose tissue-derived mesenchymal stem cells (ADMSC) on ¹³¹I-Radioiodine (RAI)-induced salivary gland damage in rats. Materials and Methods: Study population consisted of controls (n:6) and study groups (n:54): RAI (Group 1), ADMSC (Group 2), amifostine (Group 3), RAI+amifostine (Group 4), concomitant RAI+ADMSC (Group 5) and RAI+ADMSC after 48 h (Group 6). We used light microscopy (LM), transmission electron microscopy (TEM), and salivary gland scintigraphy (SGS), and analyzed data statistically. Results: We observed the homing of ADMSC in salivary glands at 1^st month on LM. RAI exposure affected necrosis, periductal fibrosis, periductal sclerosis, vascular sclerosis and the total sum score were in a statistically significant manner (P < 0.05). Intragroup comparisons with LM at 1^st and 6^th months revealed statistically significant improvements in Group 6 (P < 0.05) but not in Groups 4 and 5. Intergroup comparisons of the total score showed that Groups 4 and 5 in 1^st month and Group 6 in 6^th month had the lowest values. TEM showed vacuolization, edema, and fibrosis at 1^st month, and an improvement in damage in 6^th month in Groups 5 and 6. SGSs revealed significant differences for the maximum secretion ratio (Smax) (P = 0.01) and the gland-to-background ratio at a maximum count (G/BGmax) (P = 0. 01) at 1^st month, for G/BGmax (P = 0.01), Smax (P = 0.01) and the time to reach the maximum count ratio over the time to reach the minimum count (Tmax/Tmin) (P = 0.03) at 6^th month. 1^st and 6^th month scans showed differences for Smax and G/BGmax (P = 0.04), but not for Tmax/Tmin (p > 0.05). We observed a significant deterioration in gland function in group 1, whereas, mild to moderate deteriorations were seen in protective treatment groups. Conclusions: Our results indicated that ADMSC might play a promising role as a protective/regenerative agent against RAI-induced salivary gland dysfunction.

Aim To evaluate retrospectively the additive clinical value of combined thyroglobulin (Tg) and antithyroglobulin antibody (TgAb) measurements to define recurrent and persistent disease in patients with differentiated thyroid cancer. Materials/methods 181 patients with differentiated thyroid cancer were included in the study. The nonstable disease group (recurrent and persistent disease) had 61 patients with 24–36 months follow-up period. The stable disease group (without recurrence or persistence) had 120 patients with 21–28 months follow-up period. We compared Tg and combined Tg–TgAb levels on the sixth month after the ablation between two groups. Results Optimal threshold values for Tg, TgAb measurements were calculated statistically as 4.45 ng/ml and 27.8 IU/ml. Optimal sensitivity and specificity for 4.45 ng/ml Tg levels were 52.5 and 91.7%. We also evaluated different Tg threshold values. We found sensitivity was 54.2% and specificity 86.7% for 2 ng/ml and sensitivity was 40.7% and specificity 96.7% for 10 ng/ml Tg levels. By the odds ratio (OR) rule, the obtained sensitivity and specificity were 68.3 and 90% (if Tg>10 ng/ml or TgAb>27.8 IU/ml), 78.3 and 90% (if Tg>4.45 ng/ml or TgAb>27.8 IU/ml), and 80% and 85% (if Tg>2 ng/ml or TgAb>27.8 IU/ml). Sensitivity increased with statistical significance from 52.5 to 78.3% (P0.05) for the optimal thresholds. Conclusion Combined Tg–TgAb values were found more useful than only Tg for recurrent and persistent diseases. Combined Tg and TgAb measurements seemed to be a useful marker.