[Geographic differences in iodine supply in the Silesia terrain in relation to thyroid cancer risk]. / Zróznicowanie geograficzne podazy jodu na ternie województwa slaskiego w aspekcie ryzyka raka tarczycy.

Risk factors associated with differentiated thyroid carcinoma depend on its histotype. Follicular carcinoma is described as a predominant type in the areas with iodine deficiency, in opposite to papillary thyroid cancer. The incidence of thyroid cancer and its histotypes varies considerably throughout Silesia (data obtained from the Institute of Oncology Cancer Register, Gliwice). The factors responsible for these differences are unknown. The aim of our study was to evaluate the present iodine supply in Silesia region and to relate it to the incidence of the various histotypes of thyroid carcinoma. Urinary iodine excretion observed in 7-11 year-old-children was used as a parameter of iodine supply and measured in the group of 1037 school children in sixteen localities, equally dispersed throughout Silesia. Urine samples were obtained to measure iodine concentration by the modified Sandell-Kolthoff's catalytic method. Mean incidence rates of papillary and follicular thyroid carcinoma were calculated for regions of Silesia by averaging the rates of the communities in each region. Despite the intensive iodine prophylaxis the persistent symptoms of iodine deficiency were observed. There were significant differences in children's ioduria among investigated regions. The percentage of low ioduria (lower then 100 micrograms/l) varied from 35.7% to 87.7%. We observed no correlation between age-adjusted rates for histotypes of thyroid carcinoma and the percentage of urine iodine below 100 micrograms/l, which served as an estimation of iodine deficiency. Our study indicates that Silesia is still an area of moderate iodine deficiency. We were unable to explain the factors responsible for the observed differences in the incidence rates of papillary and follicular thyroid carcinoma.

[Prospective analysis of criteria for interpreting measurements of thyroglobulin serum concentration during conditions of endogenous TSH stimulation in serum of patients with differentiated thyroid carcinoma]. / Prospektywna analiza kryteriów interpretacyjnych oznaczania stezenia tyreoglobuliny w warunkach stymulacji endogennym TSH w surowicy chorych na zróznicowane raki tarczycy.

The aim of this study was the assessment of diagnostic value of thyroglobulin serum measurement in patients with DTC during endogenous TSH stimulation. Thyroglobulin was measured by immunofluorometric method (Delfia-Wallac) in patients after combined surgery and I131 ablation. Predictive values for two threshold levels 10 and 30 ng/ml were compared. At 5 years follow up it has been demonstrated, that Tg values higher than 10 ng/ml were the true signals of DTC relapse only in 46% patients. Tg values higher than 30 ng/ml were associated with disease progression in 65% of patients. Thus, we accept Tg concentration of 30 ng/ml measured during endogenous TSH stimulation as a good cut-off limit for the detection of DTC progression. Reduction of this threshold up to 10 ng/ml is associated with the increased risk of false positive results.

Association of polymorphism of LTalpha and TNF genes with Graves' disease.

Graves' disease (GD) is an autoimmune disease, which develops on the basis of an interaction between genetic, environmental and endogenous factors. GD is associated with some HLA genes. Closely linked with them are TNF genes (TNF and LTalpha). Their role in the pathogenesis of GD is still unclear. Two functional polymorphisms within TNF genes include a substitution of G with A in intron I of LTalpha gene and the same one at position -308 in the TNF gene promoter. We carried out a case-control study for the analysis of the contribution of TNF genes to GD in Polish patients. 156 patients with GD diagnosed by clinical data were investigated and compared to 80 healthy persons with negative familial anamnesis. Both TNF and LTalpha were analysed by PCR/Nco I RFLP. The allelic frequency of the rarer TNF2 (A) allele, was 24.7% in GD patients, significantly higher than in healthy persons (9.3%; p<0.0001). The OR was 4.38 for this allele. The frequency of heterozygotes was 41.8% in GD, as compared to 13.6% in the control group. The allelic frequency of the rarer LTB*1 (G) allele was also significantly increased: from 21.9% in the control group to 37.2% in GD patients (p<0.01; OR 2.81). The frequency of heterozygotes was 48.7% in GD, and 28.8% in the control group. The results indicate that TNF genes may contribute to GD in the Polish population.