From the Guidelines
NT-pro BNP (B-type Natriuretic Peptide) is not indicated for the diagnosis, monitoring, or management of breast cancer. NT-pro BNP is primarily a cardiac biomarker used to diagnose and monitor heart failure and other cardiac conditions, as stated in the studies 1. It is released by cardiac muscle cells in response to stretching caused by increased pressure or volume overload in the heart. In clinical practice, NT-pro BNP is used to help diagnose heart failure, assess its severity, guide treatment decisions for cardiac conditions, and monitor response to heart failure therapy.
For breast cancer, appropriate diagnostic tests include:
- Imaging (mammography, ultrasound, MRI)
- Tissue biopsies
- Specific tumor markers such as CA 15-3, CA 27.29, or CEA, though these tumor markers are primarily used for monitoring rather than diagnosis, as mentioned in the studies 1. If you're evaluating a patient with breast cancer who also has cardiac symptoms, NT-pro BNP might be relevant to assess for heart failure, particularly in patients receiving cardiotoxic chemotherapy, but it has no role in the primary diagnosis or management of breast cancer itself, as supported by the studies 1.
The use of NT-pro BNP in asymptomatic patients with cancer remains largely investigational, and there is a need for additional studies to clarify its role in cardiac troponin and natriuretic peptide assessment during cancer therapy, as stated in the study 1. However, the most recent and highest quality study 1 suggests that NT-pro BNP may be useful in monitoring cardiac dysfunction in patients with cancer, but its use is not recommended as a routine test at present.
In terms of monitoring cardiac dysfunction in patients with breast cancer, the study 1 suggests that advanced echocardiographic measures such as longitudinal strain and high-sensitivity cardiac troponin I may be useful in detecting cardiotoxicity early on. However, the primary use of NT-pro BNP remains in the diagnosis and management of heart failure, and not in the diagnosis or management of breast cancer, as supported by the studies 1.
From the Research
NT-proBNP and Cardiotoxicity in Breast Cancer Patients
- NT-proBNP is a serum biomarker of myocardial stress that may be used to predict cardiotoxicity in breast cancer patients treated with trastuzumab 2, 3, 4.
- Studies have shown that high levels of NT-proBNP are associated with an increased risk of trastuzumab-induced cardiotoxicity (TIC) 3, 4.
- A cut-off point of 276.5 pg/ml for NT-proBNP and an increase in NT-proBNP by 75.8 pg/ml from baseline may be used to detect TIC with a sensitivity of 100% and a specificity of 95% 3.
- NT-proBNP levels above the upper limit of the normal range adjusted to age or diabetes mellitus may be associated with a higher risk of developing cardiotoxicity 4.
Risk Factors for Cardiotoxicity
- Cardiovascular disease risk factors, advanced age, and previous anthracycline treatment predispose to trastuzumab-induced cardiotoxicity (TIC) 5.
- Diabetes mellitus and high NT-proBNP levels are significant risk factors for TIC 4.
- Atrial fibrillation and lower baseline left ventricular ejection fraction (LVEF) are also associated with an increased risk of TIC 3.
Monitoring and Prevention of Cardiotoxicity
- Cardiac biomarkers such as troponins and pro-BNP and imaging assessments such as echocardiogram before and during trastuzumab therapy may help in early identification of TIC 5.
- Initiation of beta-adrenergic antagonists and angiotensin converting enzyme inhibitors may prevent TIC 5.
- Screening and prediction of cardiotoxicity, referral to a cardio-oncology specialist, and initiation of effective prophylactic therapy may all improve prognosis in patients receiving HER2-directed therapy 5.