Cardiotoxicity and Cancer
This is a sobering report that should be ready thoughtfully but without panic. One of my ongoing themes is post treatment issues, and this surely counts as a big one for some women. As always, the immediate risk of the cancer outweighs concerns about eventual trouble from the treatment, but this is concerning. Generally speaking, the possible cardiac risks from breast cancer treatment come from a few specific drugs (e.g. Adriamycin and herceptin) and/or from radiation to the left breast. Radiation is very carefully planned, and every attempt is made to avoid the heart (another reason why it matters where you are treated; you want really good and smart people handling this). In terms of the drugs, there is a lifetime limit for the amount of Adria that one can receive and heart function is carefully followed for women who are getting herceptin. I have known women with advanced disease who were getting heceptin indefinitely and who had to take a break from it for a couple of months. Then, their hearts recovered, and the drug was safely started again.
From Oncology Stat:
Cardiotoxicity in Cancer Patients: Often More Malignant Than Cancer
The emerging field of cardio-oncology
Dr. Herrmann: Every so often, you encounter some skepticism regarding the emerging discipline of cardio-oncology. The very reason, however, this discipline is emerging is the impressive outcome improvement for a number of malignancies over the past decades. In fact, survival outcome of a number of cancers is now better than that of heart failure. In this sense, heart failure is, indeed, more malignant than cancer.
Years ago, we would have not had this conversation; but now, with a number of malignancies being turned into chronic diseases, similar to, for instance, rheumatoid arthritis, collateral damage matters, and this cannot be ignored anymore. So, I'm happy that this topic is receiving more and more attention to improve the overall survivorship of our patients.
OncologySTAT: Would you discuss some of the challenges of treating cancer patients with cardiovascular comorbidities? Dr. Herrmann: There is a great article which illustrates these challenges very nicely. It was published in the Journal of the
National Cancer Institute in January 2010, authored by colleagues from the oncology unit in Milan, Italy. They coined it the "sliding door" concept, and it is as follows.1
Let's consider a patient, 75 years of age, with occult colorectal carcinoma and ischemic heart disease, both of which not known at the time of the initial visit. If the patient slides through the door of cancer screening first, then he or she will undergo fecal occult blood testing, and then, if that's positive, a colonoscopy. At the end, the patient will be diagnosed with colorectal cancer —hopefully early—and undergo surgery and even chemotherapy, which can lead to profound cardiovascular side effects to the point of heart failure, especially if there is known or unknown pre-existing ischemic heart disease. At that point, the patient gets referred to the cardiologist, which is less than ideal.
If, on the other hand, the patient, for whatever reason, gets seen by a cardiologist or a cardiology-minded internist early on—before any cancer screening—he or she might end up with a stress test. If that test is positive, the patient is sent to the catheterization lab, and, before we know it, that patient has multiple drug-eluting stents in place, is on dual antiplatelet therapy, and, after a couple of months, develops a gastrointestinal bleed. After that delay, the patient is eventually diagnosed with colon cancer, but, possibly, due to its later stage, it is found that he or she has metastatic disease, with a potentially less optimal outcome.
So, based on these illustrating scenarios, a move has been made to view the patient more in his or her entirety, rather than through the lens of a clinician's own subspecialty, and this has been coined "cardio-oncology" and evolved toward cardio- oncology as a new discipline. The two particular challenges that this discipline is dealing with are: number one, to help patients with known cardiovascular disease undergo the most aggressive forms of cancer therapy safely; and, number two, to optimally manage patients who develop cardiovascular disease as a consequence of cancer therapy.