OBJECTIVE: Epidermal growth factor (EGF) is believed to be one of the most potent growth factors for the thyroid gland. DESIGN AND METHODS: We tested plasma EGF concentrations (radioreceptor method) in patients with non-toxic nodular goitre (NNG). Blood samples from patients with NNG were collected on the day before the surgery, during subtotal thyroidectomy (sTx)--from peripheral and thyroid veins, on the 3rd day after sTx, 3 months after sTx, and 9 months after the surgery. RESULTS: Before the operation, the mean plasma EGF concentration in 50 women with NNG was significantly higher (1.16 +/- 0.69 ng/ml; mean +/- S.E.) than that in 32 control female patients subjected subsequently to other (non-thyroid) operations (0.41 +/- 0.27 ng/ml; P < 0.001), and that in 20 healthy women (0.35 +/- 0.11 ng/ml; P < 0.001), both of which groups were without goitre or had a small non-toxic diffuse goitre. The surgical treatment of NNG resulted in a significant reduction in plasma EGF 3 months after sTx (0.56 +/- 0.22 ng/ml). A further slight decrease was observed 9 months after sTx (0.44 +/- 0.14 ng/ml). CONCLUSIONS: Our observations confirm the assumption that EGF may participate in the process of goitre formation in human subjects. However, the source of EGF involved in this process remains unclear. Some findings could suggest that plasma EGF, which was increased in patients with NNG, may be of non-thyroid origin; however, the majority of our observations strongly stress the significance of an intact thyroid in the preservation of an unchanged EGF value, suggesting a role of locally produced EGF in the pathogenesis of NNG.
J Brzezinski and A Lewinski
M. W. SZKUDLIŃSKI and A. K. LEWIŃSKI
M. W. SZKUDLIŃSKI and A. K. LEWIŃSKI
G. ZEREK-MELEŃ, A. LEWIŃSKI, M. SZKUDLIŃSKI and E. SEWERYNEK
D Slowinska-Klencka, M Klencki, S Sporny and A Lewinski
OBJECTIVE: The iodine status of the population of Poland has markedly improved over the past years. The aims of this paper were: (i) to examine the diagnostic value of fine-needle aspiration biopsy (FNAB) of the thyroid in goitre endemic regions (in conditions of improved iodine supply), and (ii) to find whether the changes in iodine supply have already influenced the clinical interpretation of cytological results. METHODS: Cytological diagnoses, based on 3782 aspirates, obtained from 3572 patients during the years 1985-1999, were verified by reference to the results of postoperative examinations. The relative occurrences of selected cytological results in 1992-1999 were also compared (patients not subjected to surgery were included). RESULTS: We have found that the frequency of neoplastic lesions significantly decreased throughout the examined period (P<0.02). The ratio of the papillary carcinoma frequency to the follicular carcinoma frequency increased from 1.7 during 1992-1993 up to 8.0 during 1998-1999 (P<0.05). The frequency of cytologically diagnosed chronic thyroiditis increased from 1.5% in 1992 to 5.7% in 1999 (P<0.001); the percentage of cytological diagnosis of "follicular neoplasm" decreased during the same time (P<0.001). The risk of malignancy significantly lowered in the cytological diagnoses of "follicular neoplasm" from 15% during 1985-1993 to 6% during 1996-1999 (P<0.05). CONCLUSIONS: The diagnostic value of FNAB during the period without proper iodine prophylaxis did not differ significantly from that during the last examined period. However, the changes in iodine supply have markedly and promptly affected the clinical significance of particular cytological results.
Z Szybinski, F Delange, A Lewinski, J Podoba, M Rybakowa, R Wasik, L Szewczyk, B Huszno, F Golkowski, E Przybylik-Mazurek, M Karbownik, T Zak, J Pantoflinski, M Trofimiuk and I Kinalska
BACKGROUND: Iodine prophylaxis in Poland started in 1935 and has been interrupted twice: by World War II and in 1980 for economic reasons. Epidemiological surveys carried out after the Chernobyl accident in 1989 as well as in 1992/1993 and in 1994 as a 'ThyroMobil' study, revealed increased prevalence of goitre in children and adults. Ninety per cent of Poland was classified as an area of moderate iodine deficiency, and 10%, in the seaside area, as mild iodine deficiency territory. Iodine prophylaxis based on iodisation of household salt was introduced again in 1986 as a voluntary model and in 1997 as a mandatory model with 30+/-10 mg KI/kg salt. OBJECTIVE: The evaluation of the obligatory model of iodine prophylaxis in schoolchildren from the same schools in 1994 and 1999. METHODS: Thyroid volume was determined by ultrasonography. Ioduria in casual morning urine samples was measured using Sandell-Kolthoff's method, within the framework of the ThyroMobil study. RESULTS: Goitre prevalence decreased from 38.4 to 7% and urinary iodine concentration increased from 60.4 to 96.2 microg/l mean values between 1994 and 1999. In four schools the prevalence of goitre diminished below 5%. In 1999, 70% of children excreted over 60 microg I/l, and 36% over 100 microg I/l, whereas in 1994 the values were 44 and 13% respectively. CONCLUSION: The present findings indicate that iodine prophylaxis based only on iodised household salt is highly effective.