Statistical and general data on thyroid carcinoma associated with autoimmune thyroiditis in the Republic of Moldova

In medical practice, the early diagnosis of thyroid cancer is difficult because the neoplasm coexists or develops against the background of thyroid nodulo-inflammatory pathologies, which have a slow evolution.

In conclusion, the main problem related to autoimmune thyroiditis with clinical suspicion of malignancy is to confirm the preoperative oncological element in order to assess the volume of subsequent surgical treatment performed. In most cases, starting from the dimensions, ultrasound, clinical aspect, a true result is not obtained and the study of the epidemiology of tumor diseases will contribute to the knowledge of the dynamics and specificity of the oncological patient of thyroid profile, later with the development of personalized prophylactic measures to combat cancer.

Material and methods

The research was conceived as a prospective, selective study. 234 patients were enrolled, who were treated in the scientific laboratory tumors of the head and neck region of the Oncological Institute. The study was conducted during the years 2017-2020 with the approval of the Research Ethics Committee of the „Nicolae Testemitanu” State University of Medicine and Pharmacy of the Republic of Moldova, minutes № 76 from 14.11.2016. Patients met the criteria for inclusion in the study (patient consent with informed consent, age, patients with thyroid cancer developed on a healthy background and on the background of autoimmune thyroiditis).

The cases were divided into 2 groups, group 1 was in turn divided into 2 groups:

1. Lot CT (thyroid carcinoma) + TA (autoimmune thyroiditis) (PE +) (eco-guided puncture)
   Lot CT + TA (PE-)
2. Lot CT + FS (healthy background)

All patients in group I group 1 underwent ultrasound-guided puncture of thyroid nodules.

In order to distribute the patients according to the territorial administrative unit, we consulted the national statistics office. According to which the administrative-territorial units were distributed in the northern, central and southern areas of the country:

• in the northern area were included the districts: Balti, Briceni, Donduseni, Drochia, Edinet, Falesti, Floresti, Glodeni, Ocnita, Riscani, Singerei, Soroca;
• in the center area: Chisinau, Calarasi, Criuleni, Dubasari, Hincesti, Ialoveni, Nisporeni, Orhei, Rezina, Straseni, Soldanesti, Telenesti, Ungheni, Anenii Noi;
• in the southern area: Basarabeasca, Cahul, Cantenir, Caușeni, Cimișlia, Leova, Ștefan-Vodă, Taraclia, U.T.A Găgăuzia.

Statistical analysis performed

Data series analysis was performed using the statistical applications of Microsoft Excel and the specialized software SofaStats ver. 1.4.6 (freeware). The data are presented in the form of absolute and relative values.

Results

During these years (2017-2019), in the National Cancer Registry were registered 810 primary patients with confirmed histopathological diagnosis of thyroid carcinoma, of which 163 patients were with thyroid cancer associated with autoimmune thyroiditis, 215 have were patients with thyroid cancer developed on a healthy background and 432 patients had thyroid carcinoma developed on the background of other pathologies in Table 1.

The study included only primary patients, who had as a substrate for healthy background development and association with autoimmune pathology, the latter registering a continuous increase during the years 2017-2019 (Figure 1).

According to the data following the distribution by gender, we observe an identical percentage distribution for the cases included in the CT + TA group in both groups, where female patients predominate, constituting 96,4%, which represents 108 cases, and in the CT + FS group they constitute 80.3%, which represents 98 cases. The ratio of women / men in the CT + TA group constituting 27/1 and, in the CT + FS group 4/1. The gender distribution reveals a higher incidence of the disease in women compared to men, especially in the case of the association of thyroid carcinoma with autoimmune thyroiditis.

According to the data following the distribution by gender, we observe an identical percentage distribution for the cases included in the CT + TA group in both groups, where female patients predominate, constituting 96,4%, which represents 108 cases, and in the CT + FS group they constitute 80,3%, which represents 98 cases. The ratio of women / men in the CT + TA group constituting 27/1 and, in the CT + FS group 4/1. The gender distribution reveals a higher incidence of the disease in women compared to men, especially in the case of the association of thyroid carcinoma with autoimmune thyroiditis.

According to the distribution by living environment, the comparative data are practically identical by lots. In the CT + TA group, from the rural area, came 50 (44,7%) patients from the total, respectively from the urban area 62 (55,2%) cases included in the study. In the CT + FS group, from the rural area, came 55 (45,1%) patients from the total, respectively from the urban area 67 (54,9%) cases included in the study.

Assessing the territorial-administrative region of origin of the patients, a predominance of the inhabitants of the central and southern region of the Republic of Moldova was found among the patients included in the study (Table 3).

Discussions

According to the literature, thyroid carcinoma is associated with autoimmune thyroiditis in an average of 1% to 75% of cases. Respectively Dailey, 1955, USA – 12,6%; Siriweera, 2010, Sri Lanka – 9,46%; Kim, 2011, South Korea – 29,9%; Okayasu, 1995, Japan – 46,2-76,0%; Yoon, 2012, South Korea – 28,7%; Consorti, 2010, Italy – 36.2%; Cipolla, 2005, Italy – 27,6% [14-20]. The results of our study show a growing association per year of these pathologies from 17-29%.

Throughout the literature, the highest incidence of thyroid carcinoma is in the second, third and fourth decades of life. However, in the last two decades, there has been an increase in the incidence of thyroid cancer in the fourth and fifth decades of life. Increased diagnosis can be attributed to accidental discoveries of tumors in imaging studies, such as ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET), performed for other reasons, young patients up to 55 years of age also prevailed [13].

An obvious difference between men and women is in terms of sex hormones and their influence on different systems in the body. The fluctuation of sex hormones during a woman's menstrual cycle and pregnancy has been hypothesized as a reason for gender disparity in thyroid cancer [11, 12]. Thyroid cancer had an incidence rate 2.9 times higher in women (female: male ratio 16.3: 5.7-2006) [13]. According to the data of A. Ţîbîrnă in the 2010 study “Epidemiological, clinical-morphological and surgical features of adenoma and thyroid cancer” - the ratio of women / men is 8:1 [5]. The distribution of patients by sex reveals a higher incidence of the disease in women, compared to men, a fact present in the case of the association of thyroid carcinoma with autoimmune thyroiditis - also demonstrated in the present study.

According to A. Ţîbîrnă 's data, in the study conducted in 2010 in the Republic of Moldova, after the distribution of thyroid cancer patients according to the living environment, patients from urban areas prevailed – 63%, this prevalence was observed in the present study.

In order to investigate the incidence of cancer of the thyroid gland in the Republic of Moldova depending on the territorial-administrative unit, these data were analyzed. The distribution of patients according to the territorial administrative unit (incidence per 100 thousand population with habitual residence) reported a higher prevalence of patients from the southern and central region of the country. The study performed by A. Ţîbîrnă in 2010 showed a higher prevalence in the northern and center administrative units of the Republic of Moldova [15].

Conclusions

Thyroid carcinoma associated with autoimmune thyroiditis is on the rise in the Republic of Moldova. This nosology mostly affects young people up to the age of 55 and predominates in females. southern Republic of Moldova. According to the distribution of patients by blood type, we observe a predominance of „O” blood group.

Competing interests

None declared

Author’s ORCID ID

Ina Sclifos -https://orcid.org/0000-0003-3820-559X

References

1. Globocan 2018 [Internet]. 2019. p. 2018–9. Available from: https://gco.iarc.fr/today/data/factsheets/cancers/32-Thyroid-fact-sheet.pdf
2. Registrul Naţional de Cancer al Republicii Moldova
3. Cancerul glandei tiroide , PCN 200 , Chişinău 2013
4. Трапезникова Н.Н. М., Онкология ,Медицина, 1981
5. Negri E., Dal Maso L., Ron E. et al. O analiză combinată a studiilor caz-control ale cancerului tiroidian. II. Factori menstruali și reproductivi. Controlul cauzelor cancerului. 1999; 10: 143–155.
6. Perrier N.D., Brierley J.D., Tuttle R.M. Carcinom tiroidian diferențiat și anaplazic: modificări majore în comitetul mixt american pentru cancer, ediția a opta, manualul de stadializare a cancerului CA Cancer J Clin. 2017; 68: 55-63
7. Kilfoy B.A., Devesa S.S., Ward M.H. et al. Sexul este un modificator de efect specific vârstei pentru cancerele papilare ale glandei tiroide. Cancer Epidemiol. Biomarkeri Prev. 2009; (18) : 1092–1100.
8. Rahbari R., Zhang L., Kebebew E. Thyroid cancer gender disparity, Future Oncol, 2010 Nov; 6(11): 1771–1779.
9. Abbas Ali Tam, Didem Özdemir, Sevgül Fak, Muhammet Cüneyt Bilginer, Reyhan Ersoy, Bekir Çakır Grupurile sanguine ABO, factorul Rh și riscul de cancer al tiroidei: la „B” sau nu la „B” Noiembrie 2019 Cercetare endocrină 45 (2): 1-10.
10. Dailey M. E., Lindsay S., Skahen R. Relation of thyroid neoplasms to Hashimoto disease of the thyroid gland. AMA Arch Surg, 1955;70: 291–297.
11. Okayasu I., Fujiwara M., Hara Y., Tanaka Y., Rose N.R. Association of chronic lymphocytic thyroiditis and thyroid papillary carcinoma. A study of surgical cases among Japanese, and white and African Americans. Cancer. 1995;76: 2312–2318.
12. Kim K.W., Park Y.J., Kim E.H., Park S.Y., Park do J., Ahn S.H., Park do J., Jang H.C., Cho B.Y. Elevated risk of papillary thyroid cancer in Korean patients with Hashimoto's thyroiditis. Head Neck. 2011;33: 691–695.
13. Yoon Y.H., Kim H.J., Lee J.W., Kim J.M., Koo B.S. The clinicopathologic differences in papillary thyroid carcinoma with or without co-existing chronic lymphocytic thyroiditis. Eur Arch Otorhinolaryngol. 2012;269: 1013–1017.
14. Cipolla C., Sandonato L., Graceffa G., Fricano S., Torcivia A., Vieni S., Latteri S., Latteri M.A. Hashimoto thyroiditis coexistent with papillary thyroid carcinoma. Am Surg. 2005;71: 874–878.
15. Teza de doctor în medicina ale d-lui Ţîbîrnă A. Particularităţile epidemiologice, clinico-morfologice şi chirurgicale ale adenomului şi cancerului glandei tiroide, Chișinău, 2010.