CPT® Code 81521

Oncology (breast), mRNA, microarray gene expression profiling of 70 content genes and 465 housekeeping genes, utilizing fresh frozen or formalin-fixed paraffin-embedded tissue, algorithm reported as index related to risk of distant metastasis

The CPT® Code 81521 pertains to a specific molecular genomic testing procedure used in oncology, particularly for breast cancer. This test involves mRNA microarray gene expression profiling, which assesses the expression levels of 70 content genes, also referred to as signature genes, alongside 465 housekeeping genes. The tissue samples utilized for this analysis can be either fresh frozen or formalin-fixed paraffin-embedded breast tumor tissue. The primary purpose of this test is to provide a prognostic indicator regarding the risk of distant metastasis, which is the spread of cancer from the primary site to other parts of the body. The results of this test are reported as an index that correlates with the risk of recurrence-free survival over a five-year period. This is particularly relevant for women diagnosed with Stage I or II invasive breast cancer, regardless of hormone receptor status, and with tumor sizes less than 5 cm. The process involves a pathologist examining histology slides to identify and mark tumor cells, followed by a technician isolating the mRNA from these cells. The extracted mRNA is then analyzed using a specialized computer program to generate a risk of recurrence (ROR) score. This score, in conjunction with clinical data such as cancer type, tumor size, and hormone receptor status, helps categorize the risk of recurrence into low or high categories, providing critical information for treatment planning and patient management.