Hashimotos Thyroiditis with Coexistent Papillary Carcinoma and Non-hodgkin Lymphoma-thyroid.

Lymphocytic thyroiditis and hashimoto's thyroiditis (HT) are the two main forms of autoimmune thyroiditis among which the latter is most frequent. A vast majority of cases of papillary carcinoma and primary thyroid lymphoma (PTL) arise in the setting of HT. A case of 32-year-old female who presented with thyroid enlargement, post-thyroidectomy showed hashimoto's thyroiditis (HT) with coexistent papillary carcinoma and non-hodgkin lymphoma (NHL). The immunohistochemistry was positive for CD 20, CD 45, bcl 2 for lymphoma, low and high molecular cytokeratin for papillary carcinoma. The staging studies showed no evidence of metastasis. It is thus concluded that papillary carcinoma and NHL can coexist with HT. The thyroid lymphoma or papillary carcinoma has to be thought off, whenever patients presents with sudden enlargement in a known case of HT. A patient presenting with concomitant primary thyroid lymphoma and papillary thyroid carcinoma must be judiciously evaluated, since, the treatment has to prioritize the tumor with worst stage at the time of diagnosis.