Comparative evaluation of two different dosage calculation protocols of iodine-131 in the treatment of hyperthyroidism.

OBJECTIVE: To compare the effectiveness of radioiodine therapy with estimated dose and calculated dose in hyperthyroid patients. MATERIAL AND METHOD: A prospective randomized study in 144 hyperthyroid patients referred for 131I treatment was performed between June and December 2007. The patients were divided into two groups according to the 131I dose administered, estimated group using dose based on gland size and calculated group using dose based on both gland size and 24-hour 131I uptake. Outcome assessment was done at 12 months post-treatment. RESULTS: Eleven of 144 patients were excluded due to loss to follow-up and five became euthyroid before 131I treatment. Fifty-six of 128 patients (45.3%) experienced persistent/recurrent hyperthyroidism, 26 (20.3%) developed hypothyroidism, and 44 (34.4%) were euthyroid. Outcome was unrelated to the methods of I-131 dosing. Only gender and goiter size were found to be correlated with the clinical outcomes. CONCLUSION: An estimated I-131 dosing method using gland size determined by palpation is as effective as calculated method using 131I uptake. This method is more cost effective and brings greater patient convenience.

Mortality-related factors in 1056 radioiodine-treated patients with well-differentiated thyroid cancer in southern Thailand.

BACKGROUND: Reported risk factors for death related to well differentiated thyroid cancer vary, possibly depending on the methods and geographical site of data collection. METHOD: To evaluate variables related to death in well-differentiated thyroid cancer (WDTC) in a population of southern Thailand, we retrospectively reviewed medical records of all those treated with radioactive iodine (I-131) at the Division of Nuclear Medicine from 1983 to 2002. We found 1056 subjects. Variables examined included present status of subjects (transfer, lost, died), cause of death (related and not related to WDTC), duration of follow-up since surgery, largest size of tumor (when available), gender, histology (follicular or papillary, with mixed included in papillary), age of surgery, and site of spread when treated. Survival from WDTC death utilized Kaplan-Meier and Cox regression analysis. RESULTS: The median follow-up was 7 years, while only 4 years elapsed from surgery for those who died. We did not know the status of 16% of the subjects despite attempts to contact them. Survival was not affected by age, gender, or maximum size of tumor. Age at surgery was significant only for the group older than 55 years, with a 10-year survival of 76%. The spread of the disease that affected survival can be localized to the aerodigestive tract (10-year survival of 65%) and metastases associated with bone fracture (10-year survival 34%), while other metastases (including asymptomatic bone metastases) exhibited a 10-year survival of 93%. Neither lymph node spread nor elevated Tg at maximum stimulation predicted survival. CONCLUSIONS: To better predict survival of WDTC, site of spread and degree of spread has to be specific.

Primary vesicoureteral reflux mediated renal scarring after urinary tract infection in Thai children.

AIM: To evaluate the association between primary vesicoureteral reflux (VUR) and renal scarring in children using 99 m Technetium-labelled dimercaptosuccinic acid (DMSA). METHODS: Children attending at Songklanagarind Hospital from 1987 to 2002 were evaluated. RESULTS: Ages at diagnosis of VUR in 46 boys and 52 girls were 1.1+/-1.6 and 2.9+/-2.5 years, median 0.6 and 2.3 years, respectively (P<0.001). DMSA scans were performed at 4.1+/-3.6 years. Renal parenchymal damage was detected in 34 kidneys (22%) of 154 demonstrated refluxing ureters, and one kidney (2%) of 42 non-refluxing ureters (P=0.002). Of 79 refluxing ureters in boys and 75 refluxing ureters in girls, there were 25 and nine renal scars, respectively (32% and 12%, P=0.003). Renal scars in VUR grades I-V were 11%, 7%, 12%, 44% and 64%, respectively (P<0.001). Multivariate analysis revealed that high grade VUR (P<0.001), age of diagnosis of VUR greater than 5 years (P=0.001), and male gender (P=0.002) were the most significant risk factors for renal scarring. CONCLUSION: High-grade VUR, age of diagnosis of VUR greater than 5 years and male gender were the most significant risk factors for renal scarring.