Abstract
Purpose: In this study, we aimed to investigate the changing pattern in thyroid cancer histology and cancer stage.
Materials and Methods: A total of 321 thyroid cancer patients who admitted to our institute between December 1995 and December 2005 were retrospectively analyzed in 2 different time intervals (Period I = 174 patients, December 1995 - December 2001 and Period II = 147 patients, January 2002 - December 2005).
Results: The incidence of cancer increased significantly between both groups (11.6% vs. 20.7% and p<0.05). Papillary cancer incidence increased from 73.8% to 84.6% (p>0.05), while follicular cancer decreased from 16% to 2.7% (p<0.05). Nevertheless, according to DeGroot's prognostic index, rate of patients in Class 1 and 2 increased (p>0.05), while it decreased in Class 3 (p<0.05).
Conclusion: This study reveals a change in thyroid cancer. Whether iodine substitution has a major impact on it has to be studied by determining the sufficiency of iodine prophylaxis and measuring urine iodine excretion of the population.
Keywords:
thyroid cancer, iodine prophylaxis, cancer stage
References
1Türk Gıda Kodeksi, Yemeklik Tuz Tebliği. Dokuz Temmuz 1998 tarih ve 23397 sayılı Resmi Gazete, Teblig No:98/11
2Farahati J, Geling M, Mader U, et al. Changing trends of incidence and prognosis of thyroid carcinoma in lower Franconia, Germany, from 1981-1995. Thyroid. 2004;14:141-147
3Harach HR, Williams ED. Thyroid cancer and thyroiditis in the goitrous region of Salta, Argentina, before and after iodine prophylaxis. Clin Endocrinol (Oxf). 1995; 43:701-706
4Harach HR, Escalante DA, Onativia A, et al. Thyroid carcinoma and thyroiditis in an endemic goitre region before and after iodine prophylaxis. Acta Endocrinol (Copenh). 1985;108:55-60
5Levi F, Franceschi S, Te VC, et al. Descriptive epidemiology of thyroid cancer in the Swiss Canton of Vaud. J Cancer Res Clin Oncol. 1990;116: 639-647
6DeGroot LJ, Kaplan EL, McCormick M, et al. Natural history, treatment, and course of papillary thyroid carcinoma. J Clin Endocrinol Metabol 1990;71:414–424
7Galanti MR, Hansson L, Bergström R, et al. Diet and the risk of papillary and follicular thyroid carcinoma: a population-based case-control study in Sweden and Norway. Cancer Causes Control. 1997;8:205-214
8Burgess JR, Dwyer T, McArdle C, et al. The changing incidence and spectrum of thyroid carcinoma in Tasmania (1978–1998) during a transition from iodine sufficiency to iodine deficiency. J Clin Endocrinol Metab. 2000;85:1513–1517
9Franceschi S. Iodine intake and thyroid carcinoma – a potential risk factor. Exp Clin Endocrinol Diabetes. 1998;106:38-44
10Bacher-Stier C, Riccabona G, Totsch M, et al. Incidence and clinical characteristics of thyroid carcinoma after iodine prophylaxis in an endemic goiter country. Thyroid. 1997;7:733-741
11Köhrle J. The trace element selenium and the thyroid gland. Biochemie. 1999;81:527-533
12McTiernan AM, Weiss NS, Daling JR. Incidence of thyroid cancer in women in relation to reproductive and hormonal factors. Am J Epidemiol, 1984;120:423-435
13Goodman MT, Kolonel LN, Wilkens LR. The association of body size, reproductive factors and thyroid cancer. Br J Cancer 1992;66:1180-4.
14Williams ED. Chernobyl and thyroid cancer. J Surg Oncol. 2006;94:670-677
15Erdoğan MF. İkinci Tiroid Hastalıkları Kongresi – İstanbul 2002
16Darcan S, Unak P, Yalman O, et al. Determination of iodine concentration in urine by isotope dilution analysis and thyroid volume of school children in the west coast of Turkey after mandatory salt iodization. Clin Endocrinol. 2005;63:543–548
