de Rienzo-Madero, Beatriz1; Amichaud, Regis1; Kraimps, Jean Louis1; Donatini, Gianluca1
1 Department of Endocrine Surgery, University Hospital of Poitiers, Poitiers, France
Background/ Purpose: Hyperthyroidism has been considered a protective factor for thyroid cancer. However, in the literature, an association between these two entities ranges up to 18.3%. We describe the prevalence of thyroid cancer within hyperthyroid patients who underwent surgery at our institution.
Methods: A review of patients who underwent surgery between January 1991 and January 2015 was performed. Variables analyzed were: sex, age, clinico-biological characteristics, histology, disease extension, and type of surgical procedure. Malignancy was confirmed with final histopathology.
Results: Overall, 11140 patients underwent thyroidectomy; 1236 (11.09%) patients had hyperthyroidism, and 91 of these (7.6%) had an associated thyroid carcinoma. Fifty-one patients (56.0%) had toxic multinodular goiter, 32 (35.2%) Grave’s disease and 8 (8.8%) solitary toxic adenoma. Nine patients (9.9%) required associated lymph node dissection. Cancer types were: classic papillary carcinoma in 80 patients (87.9%), follicular carcinoma in 7 (7.7%), follicular variant of papillary carcinoma in 3 patients (3.3%) and 1 medullary carcinoma (1.1%). Fourteen patients had multifocal cancer. Six of the 9 patients with lymph node extension had Graves’s disease. No distant metastasis were observed.
Conclusion: Hyperthyroidism is not a protective factor for thyroid cancer as evidenced by the same prevalence of cancer in all patients undergoing thyroidectomy (p>0.05). Our findings confirm the prevalence reported in current literature data. Thyroid cancer in Grave’s disease patients seems to be more aggressive as it shows a higher prevalence of lymph nodes metastasis compared to other subgroups of hyperthyroidism associated cancer. FNA cytology should be performed on nodular Grave’s disease.