Afirma genomic sequencing classifier performance in young patients with cytologically indeterminate thyroid nodules

Area of Science:

• Endocrinology
• Oncology
• Genomics

Background:

• The Afirma Genomic Sequencing Classifier (GSC) is established for patients over 21 years, with a 96% negative predictive value (NPV) for malignancy.
• Limited formal studies exist on Afirma GSC performance in pediatric and adolescent populations (<21 years) with indeterminate thyroid nodules (ITNs).

Purpose of the Study:

• To assess the efficacy and performance of the Afirma GSC test in patients under 21 years presenting with indeterminate thyroid nodules.
• To evaluate the negative predictive value and diagnostic accuracy of Afirma GSC in a young patient cohort.

Main Methods:

• Retrospective analysis of Afirma GSC testing data.
• Included 49 indeterminate thyroid nodules from patients aged 9-20 years.
• Outcomes were determined by histopathology or a minimum of two years of clinical follow-up.

Main Results:

• The Afirma GSC demonstrated a 100% negative predictive value (NPV) for benign results, with all 30 GSC-Benign (GSC-B) cases confirmed as benign.
• Sensitivity for detecting malignancy was 100% (14/14 GSC-Suspicious cases were malignant), and specificity was 86% (30/35 benign cases were GSC-B).
• Malignant nodules included papillary thyroid carcinomas, oncocytic carcinoma, follicular thyroid carcinomas, and a non-invasive follicular thyroid neoplasm with papillary-like nuclear features.

Conclusions:

• The Afirma GSC is a valuable tool for evaluating indeterminate thyroid nodules in young patients (<21 years).
• The test exhibits excellent negative predictive value, supporting its use in clinical decision-making for this demographic.
• Results indicate high diagnostic accuracy, comparable to its performance in adult populations.