Thyroid nodules are a common clinical problem. The diagnosis of papillary carcinoma is based on the characteristic nuclear morphology. Mostly, the pathological diagnosis of surgically removed thyroid nodules is possible by morphological examination in routine hematoxylin–eosin-stained sections; however, sometimes thyroid hyperplasia, although a completely benign condition, can display nuclear features that are similar to papillary thyroid carcinoma, a condition that makes the differentiation between both lesions a challenging task for the pathologists.Aim of the work
The aim of this study is to use immunohistochemical expression of CD56 and cyclin D1 to differentiate between benign hyperplasia and papillary carcinoma.Materials and methods
Thirty paraffin blocks were collected distributed equally between hyperplasia and papillary carcinoma. Each case was stained for antibodies against CD56 and cyclin D1.Results
A highly significant difference in CD56 expression was noticed, as CD56 positivity was seen in 13 cases of hyperplasia compared with only one papillary carcinoma case. As for cyclin D1, positive staining was observed in 46.7% of hyperplasia cases and 40% of papillary carcinoma cases, but these results were insignificant.Conclusion
We conclude that CD56 is an excellent negative marker for papillary carcinoma, so it can be used to differentiate between benign hyperplasia and papillary carcinoma, which is not the case for cyclin D1.