I talked about the burden of cardiovascular disease after cancer. These days, as more and more patients survive cancer long-term, different types of toxicities and cardiac toxicity is becoming by far one of the most important because it leads to significant disability and potentially premature mortality. Many oncologists are very familiar that common drugs, in particular for treatment of breast cancer, can lead to cardiac toxicity, but what is discovered more and more is newer drugs can cause different types of cardiac toxicities. For example, immunotherapy can be associated with myocarditis and there is a higher risk of thrombosis, so we now need to recognise that there are different types of toxicities, perhaps not the ones that are immediately apparent.
Secondly, there is more and more evidence that cancer survivors frequently have shared risk factors for cancer and for cardiovascular disease, and it is those risk factors that predispose to premature mortality from heart disease after cancer. So, as part of cancer care and good survivorship care we need to manage high blood pressure, obesity, inactivity. The good news is that advising patients to stop smoking, move, lose weight, is actually very good for cancer outcomes, and it is good for cardiovascular disease, so in a way we’re getting two for the price of one, we just need to get the message across.
How does preventing cardiovascular toxicity vary by country?
In Vietnam perhaps obesity may not be the biggest issue, but as developing countries become of middle income, the lifestyle changes, inactivity increases, obesity rates actually go up. Of course, there are other risk factors that perhaps are a little bit more prevalent in the low and middle income countries, for example higher rates of smoking and higher air pollution. So those issues perhaps need to be mitigated as well.
Are you advising monitoring for cardiovascular toxicity in breast cancer patients?
Yes, and that depends really on different types of risk factors and different types of treatments. Naturally, if you have cancer that has got short life expectancy perhaps cardiovascular disease may not be a major priority, but as we’re getting more and more survivors who survive long term, if they receive cardiotoxic treatments they may need to have attention paid to risk factor management, in to surveillance, things like echocardiography to check the heart function. But, most importantly, awareness of healthcare providers and patients that this is potentially an important risk factor.
For older women with breast cancer in the western populations, mortality from cardiovascular disease actually exceeds that from cancer in long-term follow up so this is an important issue, and it’s an issue that’s actually quite easy to manage if you know about it.