Carcinoma which arises in the thyroglosal cyst is -

Ans. is 'a' i.e., Papillary carcinoma o Thyroid carcinomas arising after radiation or in thyrogiossal cyst are papillary type. Various genes involved in thyroid carcinomas areo Papillary-o Tyrosine kinase receptors RET or NTRK1o RAS mutationo BRAF oncogeneo Follicular-o RAS oncogene (NRAS, HRAS and KRAS)o PAX 8- PPARrl thanslocationo Medullary-o RETprotooncognePapillary thyroid carcinomao It is the most common type of thyroid cancer.o Radiation induced thyroid carcinoma and carcinoma in thyrogiossal cysts are of papillary type.o Carcinoma cells have nuclei which contain finely dispersed chromatin, which imparts optically clear or empty appearance, giving rise to the ground glass or Orphan Annie eye nuclei.o Invagination of cytoplasm may give rise to the appearance of intranuclear inclusins (Pseudoinclusions) or intranuclear grooves - the diagnosis of papillary carcinoma is based on these nuclear features.o Psammoma bodies are presento Lymphatic metastasis may be seen but involvement of blood vessels is rare.