What is Oncotype DX Test?

The Oncotype DX test is a genomic test performed on a patient’s breast tumor tissue that analyses the activity of a group of genes that can influence how cancer is likely to behave and respond to treatment. Currently, it is the only multigene assay validated for prediction of chemotherapy benefit, as well as for prognosis. 

Why is the Oncotype DX test used? 

The test helps doctors to predict whether breast cancer is likely to recur after treatment, and if the patient will benefit from chemotherapy. It's often used in early-stage, hormone receptor-positive (HR+), HER2-negative breast cancer. 

The test works by examining the activity of 21 genes within a patient's breast cancer cells and using this information to assign a Recurrence Score. This score ranges from 0 to 100 and corresponds with a specific likelihood of breast cancer recurrence within 10 years of initial diagnosis. 

Oncotype DX Score   

Here's a general breakdown of what the scores mean: 

• A low score (0-17) suggests a low risk of recurrence; these patients are likely to derive minimal, if any, benefit from chemotherapy. 
• A mid-range score (18-30) suggests a moderate risk of recurrence; the benefit derived from chemotherapy can vary. 
• A high score (31-100) suggests a high risk of recurrence; these patients are likely to benefit from chemotherapy. 

The Oncotype DX test provides additional information to help personalise treatment plans. However, it's only one piece of the puzzle. Other factors, such as the size and grade of the tumor, the patient's age and overall health, and the patient's personal preferences, also play crucial roles in treatment decisions. The test is not appropriate for all types of breast cancer, and its use should be discussed with your doctor.