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When Michael Ewer, MD, JD, first began working as a cardiologist at The University of Texas MD Anderson Cancer Center in Houston, Texas, in 1978, one of his oncology colleagues was skeptical. “For you to succeed, you're going to need to know more about oncology than other cardiologists,” he told Dr. Ewer. “You'll need to know which treatments are needed for my patients and not get in my way as I try to give lifesaving chemotherapy.”

Dr. Ewer, who was hired to help oncologists learn more about the cardiac problems posed by anthracyclines, took those words to heart. He began learning as much as he could about oncology; although the term “cardioncologist” wasn't used at the time, he has clearly focused his career on that area.

He has coauthored several books on the subject, including Cancer and the Cardiopulmonary System (1984), Cancer and the Heart, (2005), and the second edition of Cancer and the Heart, due out later this year. The last incorporates new data on many of the newer chemotherapeutic agents, including trastuzumab, sunitinib, sorafinib, lapatinib,andavastin.Italsoupdatestheinformationonanthracyclines, reviews radiation effects on the heart, and examines imaging studies. Some of the cardiotoxicity functions caused by newer agents have been shown to be reversible, while anthracyclines can cause cell loss that is generally permanent, Dr. Ewer notes.

In 2005, he was the lead author on a study and an editorial that appeared in separate issues of the Journal of Clinical Oncology.1, 2 The study demonstrated the reversibility of trastuzumab-related cardiotoxicity in 38 HER2-positive breast cancer patients. These women generally improved after the drug was discontinued. Since that time, the data from this study have been confirmed and accepted, Dr. Ewer says.

The editorial, meanwhile, addressed the need to recognize a Different type of chemotherapy-related cardiac dysfunction(CRCD) than that associated with anthracycline-treated patients. Dr. Ewer and colleagues termed problems related to anthracycline type I CRCD. The cardiac toxicity associated with trastuzumab, however, was thought to be“ either less severe, or as yet below the threshold for, typical cardiac changes associated with anthracyclines,” the editorial noted. As a result, Dr. Ewer and colleagues identified a different form of Myocardial dysfunction, categorized as type II CRCD. This dysfunction does not occur in all patients, has a broad range of severity, and is not associated with identifiable ultrastructural abnormalities, the authors explained.

“In the beginning, these ideas were controversial,” says Dr. Ewer, adding that clinical trials ultimately showed that there were not as many serious cardiac events associated with the newer agents—andonly2cardiacdeathsamongmorethan10,000women participating in the trials of the type II agent, trastuzumab. “We don't have all the answers with these drugs, and we still don't know long term outcomes,” he adds. “It is the sequential use of these drugs that is creating new challenges than what we expect.”

Dr. Ewer is optimistic that the field will evolve as scientists learn to identify patients with different risks for different drugs, genetic diversity, and varying pathways in the heart—all in an effort to predict and mitigate cardiotoxicity. Although cardiac risk is always a concern, “in the end, it is survival of the patient that the cardioncologist should be equally concerned with,” he says.

Dr. Ewer adds that both oncologists and cardiologists need to break away from the “tunnel-vision approach” of treating their patients. “If both the cardiologist and oncologist would put a slightly wider angle lens on their cameras, they would have a better view of how to optimize their patients' management,” he notes.

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