Assessment of Kirsten Sarcoma Viral Gene Mutations in Non-neoplastic and Neoplastic Nodular Lesions of Thyroid in Pakistan

Objectives: To assess KRAS mutations in non-neoplastic and neoplastic nodular lesions of thyroid as the incidence of KRAS mutations in thyroid lesions in Pakistan has not been evaluated.

Methods: The cross sectional study was conducted at Basic Medical Sciences Institute, Jinnah Postgraduate Medical Center, Karachi from 2011 to 2014. 70 cases including 6 multinodular goiters, 10 hyperplastic nodules, 10 follicular adenomas, 7 WDT-UMP, 4 follicular carcinomas, 22 classical papillary carcinomas, 11 follicular variant of papillary carcinomas were subjected to standard PCR to detect KRAS mutations located at codon 12 exon 1.

Results: KRAS mutations located at codon 12 exon 1 were found in 02(2.87%) cases of multinodular goiter, 05(7.14%) hyperplastic nodules, 02 (2.87%) follicular adenoma, 03(4.2%) WDT-UMP. Among malignant lesions follicular carcinoma showed KRAS positivity 03(4.2%), classical papillary carcinoma 08(11.42%) and follicular variant of papillary carcinoma 07(10%).

Conclusion: Our data suggests strong presence of KRAS mutations in malignant tumors supporting the presence of KRAS mutations in our population particularly follicular variant of papillary carcinoma. Follicular variant is a discrete variant of papillary carcinoma having strong association with KRAS mutations.