Detecting N-RAS Q61R Mutated Thyroid Neoplasias by Immunohistochemistry

Area of Science:

• Oncology
• Pathology
• Molecular Diagnostics

Background:

• N-RAS Q61R mutations are implicated in thyroid neoplasia.
• Immunohistochemistry (IHC) for N-RAS Q61R is a new diagnostic tool.
• Reliability of IHC for N-RAS Q61R in thyroid lesions requires validation.

Purpose of the Study:

• To evaluate the diagnostic accuracy of IHC for N-RAS Q61R mutations in thyroid lesions.
• To compare IHC results with automated sequencing for N-RAS Q61R detection.
• To assess the clinical utility of IHC in managing thyroid neoplasia.

Main Methods:

• Investigated 24 thyroid lesions with indeterminate cytology using IHC (clone SP174) and automated sequencing.
• Paraffin-embedded tissue sections were stained for N-RAS Q61R expression.
• Histological analysis included follicular carcinoma, papillary cancer, follicular adenoma, and hyperplastic nodules.

Main Results:

• A 100% concordance was observed between IHC and molecular sequencing for N-RAS Q61R mutations.
• Positive IHC staining for N-RAS Q61R was detected in 4 cases, primarily cytoplasmic.
• Negative IHC results were observed in the remaining cases.

Conclusions:

• IHC for N-RAS Q61R is a highly reliable and cost-effective method for identifying mutated thyroid neoplasia.
• This IHC approach can improve the accuracy of thyroid lesion management.
• The findings support the adoption of IHC for N-RAS Q61R in clinical practice when indicated.