Thyroid cancer in Egypt: histopathological criteria, correlation with survival and oestrogen receptor protein expression.

Thyroid cancer represents approximately 1% of new cancer and oestrogen may play a role in the pathogenesis of thyroid neoplasm. We aimed to study the clinicopathological criteria and ER expression of thyroid cancer in Mansoura University (Egypt), and to correlate the survival to these clinicopathological data and ER expression. This retrospective study reviewed 644 patients with histologically proven thyroid carcinoma during the period from 2003 to 2011. 152 cases during the period between 2008 and 2011 were retrieved from the archive and examined by immunohistochemistry for oestrogen receptor-α (ER) expression. ER-α expression is significantly associated with the female sex, lymph node metastasis, TNM stage, extrathyroid extension, multifocality disease and recurrence and in the whole series (p < 0.5). The same was noticed in papillary carcinoma (PTC) except the gender of the patient. Tumour type, extrathyroid extension and ER expression were the independent prognostic factors of DFS, while in PTC, only ER expression was the independent one. The histological type was the only independent prognostic factor for OAS in the series were studied for ER expression, while extrathyroid extension was the only one that affected OAS of PTC. There was significant positive correlation with lymph node metastasis and ER expression in whole patient and PTC cases. No difference in survival between the low and high ranges of positive oestrogen expression. The prognosis of thyroid carcinoma in Egypt is similar to that occurs worldwide. ER-α expression was a significant prognostic marker for DFS in thyroid cancer and can be used as a predictive factor of lymph node metastasis.