THYROID: Edited by Lewis E. Braverman and Angela M. LeungRAS-positive thyroid nodulesAngell, Trevor E.Author Information Thyroid Section, Division of Endocrinology, Diabetes and Hypertension, The Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA Correspondence to Trevor E. Angell, MD, Thyroid Section, Division of Endocrinology, Diabetes and Hypertension, The Brigham and Women's Hospital and Harvard Medical School, 77 Louis Pasteur Avenue, HIM 641, Boston, MA 02115, USA. Tel: +1 617 525 5172; fax: +1 617 731 4718; e-mail: email@example.com Current Opinion in Endocrinology & Diabetes and Obesity: October 2017 - Volume 24 - Issue 5 - p 372-376 doi: 10.1097/MED.0000000000000354 Buy Metrics Abstract Purpose of review The current review focuses on the uncertainty regarding the management of rat sarcoma viral oncogene homolog RAS-positive thyroid nodules. The application of oncogene testing has been heralded for improving risk assessment for indeterminate cytology thyroid nodules and has grown in clinical use. RAS mutations are historically considered oncogenic. However, RAS mutation detection in thyroid nodules has proven problematic, as these mutations are found in benign and malignant lesions. Recent findings RAS-positive thyroid nodules frequently have indeterminate cytology and a finding of a positive RAS mutation identifies a significant number of benign lesions as well as thyroid cancers. Long-term follow-up of RAS-positive nodules with benign cytology shows an indolent course not consistent with eventual malignant transformation. Many RAS-positive nodules previously diagnosed as follicular variant of papillary thyroid carcinoma now will be reclassified as noninvasive follicular thyroid neoplasm with papillary-like nuclear features, indicating a more indolent nature of these RAS-positive lesions. Summary Recent findings have underscored that diagnosis of a RAS-positive thyroid nodule is not synonymous with thyroid malignancy. The ideal clinical and surgical management of these nodules remains challenging. Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved.