ACVIM 2017: Chemotherapy-Induced Vomiting and Inappetence

In a poster presented at the 2017 American College of Veterinary Internal Medicine (ACVIM) Forum in National Harbor, Maryland, researchers from Iowa State University reported results of a survey of veterinary specialists’ perceptions of vomiting and inappetence caused by chemotherapy drugs. Respondents tended not to use the agents seen as most likely to cause significant vomiting. Maropitant was the drug most commonly prescribed to treat vomiting and inappetence in patients receiving chemotherapy.

Study coauthor Chad M. Johannes, DVM, DACVIM (SAIM, Oncology), assistant professor of small animal internal medicine and oncology at Iowa State University, sat with American Veterinarian^® staff to discuss the implications of the survey.

Investigating therapies that reduce the adverse effects of cancer treatment is important, he said, “because it’s those side effects that affect quality of life and ultimately clients’ willingness to pursue therapy.” The adverse effects of chemotherapy can be severe enough to stop treatment, he added.

The incidence of chemotherapy-induced vomiting and inappetence in dogs has not been reported, wrote the study authors. Unlike in human medicine, there is no standard protocol for treating these adverse events in veterinary patients. However, effective treatments are available, they said. For example, maropitant has been shown to prevent vomiting in 95% of dogs receiving cisplatin.¹

Survey Respondents and Topics

The investigators solicited survey responses through the ACVIM oncology and small animal internal medicine listservs. They received 85 completed surveys, including 71 from oncologists and 14 from internists. The majority of respondents (71%) reported that medical oncology accounted for at least 80% of their daily practice. Survey topics were as follows:

• Perceived incidence of acute and chronic vomiting after single administration of 20 chemotherapeutics
• Severity of vomiting caused by each drug (TABLE 1)
• Use of antiemetics for prevention and treatment of chemotherapy-induced vomiting
• Use of appetite stimulants in patients receiving chemotherapy

Survey Results

Survey respondents perceived that most single-agent chemotherapy drugs were well tolerated. They indicated that cisplatin, streptozocin, dacarbazine, paclitaxel, and epirubicin were most likely to cause significant vomiting when used as individual agents. These 5 drugs were also prescribed by the fewest survey respondents.

The antiemetics most likely to be used by respondents were maropitant, ondansetron, metoclopramide, and dolasetron. Survey respondents used antiemetics more often to prevent acute vomiting (day 1 of chemotherapy) than delayed vomiting (days 2—5 after chemotherapy) (TABLE 2).

The drugs most commonly prescribed to stimulate appetite in patients receiving chemotherapy were maropitant, mirtazapine, and metoclopramide. The authors noted that maropitant was the drug most commonly used by respondents to treat both vomiting and inappetence.

Implications

Defining how veterinary oncologists and internists currently treat chemotherapy-induced vomiting and inappetence may help specialists develop guidelines for treating these adverse events, said Dr. Johannes. “The better that we can focus on improving quality of life, the better for our patients, the better for our clients, and the better for our outcomes.”

Dr. Walden received her doctorate in veterinary medicine from North Carolina State University in 1994. After an internship at Auburn University College of Veterinary Medicine, she returned to North Carolina, where she has been in companion animal general practice for over 20 years. Dr. Walden is also a board-certified editor in the life sciences and owner of Walden Medical Writing.

References:

• Vail DM, Rodabaugh HS, Conder GA, Boucher JF, Mathur S. Efficacy of injectable maropitant (Cerenia) in a randomized clinical trial for prevention and treatment of cisplatin-induced emesis in dogs presented as veterinary patients. Vet Comp Oncol. 2007;5(1):38-46.
• Veterinary Co-operative Oncology Group. Veterinary Co-operative Oncology Group - Common Terminology Criteria for Adverse Events (VCOG-CTCAE) following chemotherapy or biological antineoplastic therapy in dogs and cats v1.0. Vet Comp Oncol. 2004;2(4):195-213.