Predicting future disease

This study evaluated the use of EndoPredict in predicting late metastatic recurrence in ER+ breast cancer patients.

Hormonal treatment of estrogen receptor positive (ER+) breast cancer is routinely continued for 5 years following diagnosis. However, over 50% of all cancer recurrences, and over 66% of cancer related deaths occur more than 5 years after diagnosis (referred to as late recurrence). Recurrence often occurs in organs other than the breasts (referred to as metastatic recurrence). Recent research has suggested that some ER+ breast cancer patients should receive hormonal therapy for more than 5 years in order to reduce the risk of late recurrence. However, hormonal therapy involves several side effects, health risks and high costs. It is therefore important to identify each patient's individual risk of late metastatic recurrence in order to determine which patients may benefit to most from extended hormonal therapy.  

Genetic tests are often used to identify the presence of particular genes in cancer cells which may contribute to the risk of cancer recurrence. Several genetic tests are currently used to predict early cancer recurrence, or the risk of cancer metastasis. However, no test to date has shown any value at predicting the risk of late metastatic recurrence.

EndoPredict is a genetic test which assesses the presence of 8 different cancer-associated genes.  The EP/clin score is a prognostic scoring system which combines the results of the EndoPredict genetic test with clinical features of the tumor such as tumor size and lymph node involvement. This study evaluated the effectiveness of the EP/clin score at predicting late metastatic recurrence among breast cancer patients.

1702 patients with ER+ breast cancer were included in this study. All women were treated with hormonal therapy for 5 years. 49% of the women were classified as low risk according to their EP/clin score. Among this group of low risk women, 96.29% were indeed free of cancer recurrence after a 10 year follow-up. 

When the EP/clin score was compared to the predictive power of clinical features alone, the EP/clin score was found to be significantly more accurate at predicting late recurrence.

This study concluded that EndoPredict genetic testing provides valuable prognostic information regarding the risk of late breast cancer recurrence.

Several of the authors of this study are employed by, or are share holders of, Sividon Diagnostics, which developed and manufactures EndoPredict.