The Ki-67/MIB-1 index level and recurrence of papillary thyroid carcinoma

Thyroid Neoplasms, papillary and follicular carcinomas, are a heterogeneous group of tumors, which combined make up almost 95% of all endocrine tumors and accounts for about 1% of all malignancies. Papillary thyroid carcinoma is associated with the expression of multiple cell proliferating markers such as Ki-67/MIB-1, cyclin D1, p27, which were linked to the biological features and clinical behavior of the tumors. It is important to determine prognostic factors for survival in patients with clinical recurrence of PTMC, to more clearly determine optimal management regimens. Emerging epidemiological and clinical evidences suggest that Ki-67/MIB-1 may positivity confers a higher risk of recurrence and a worse survival in patients with PTC. This leads to the hypothesis that, it is possible to use Ki-67/MIB-1 as a prognostic marker in the thyroid tumors especially in papillary thyroid micro-carcinoma, and defined its index values closed to the papillary thyroid carcinoma as a cutoff for detection of the tumor recurrence. It is our hope that use this genes as a defined marker of cell proliferation to better understand cancer pathogenesis to prevent the recurrence or to improve the survival, and ultimately to expand therapeutics.