Risk model aids antiemetic prophylaxis in breast cancer

Last Updated: 2015-11-16

By David Douglas

NEW YORK (Reuters Health) - In patients receiving chemotherapy for early-stage breast cancer, risk model-guided (RMG) antiemetic prophylaxis can do better than relying on the physician's choice of antiemetics, according to Canadian researchers.

As Dr. Mark Clemons told Reuters Health by email, "Nausea and vomiting are among the most feared side-effects of chemotherapy for cancer patients, and in some cases the symptoms can be so debilitating that patients stop treatment. To date, physicians have treated these side effects with a range of anti-nausea drugs, following established guidelines. Unfortunately these 'cookie cutter' guidelines ignore all the personal factors that affect an individual patient's risk of being sick with chemotherapy."

In a November 12 online paper in JAMA Oncology, Dr. Clemons, of the Ottawa Hospital Cancer Centre, and colleagues noted that in earlier work they developed and prospectively validated risk models for chemotherapy-induced nausea and vomiting (CINV). These helped identify patients at high risk for acute CINV (first 24 hours after therapy) and delayed CINV (two to five days after therapy).

Dr. Clemons went on to say that this was the "first study to randomize patients between anti-sickness drugs based on their personal risk factors for nausea and vomiting (i.e. age under 40, those with a history of pregnancy-associated morning sickness or travel sickness, or those with lower alcohol consumption) or anti-sickness drugs prescribed based on more traditional physician choice."

The team randomized 324 patients undergoing chemotherapy with cyclophosphamide and an anthracycline to RMG prophylaxis or as controls to usual care via the physician's choice of antiemetics.

Patients considered to be at low risk received standard dexamethasone and a 5-HT3 serotonin receptor antagonist. Those at high risk also received aprepitant with or without olanzapine, based on their risk level. Controls got antiemetic agents at the treating physician's discretion.

In the acute period, significantly more RMG patients than controls reported no nausea (53.7% versus 41.6%). This was also the case for vomiting (91.8% versus 82.2%). Corresponding proportions in the delayed period were 39.6% versus 30.7% and 87.1% versus 78.0%.

Thus, concluded Dr. Clemons, "The study showed that incorporating personal risk factors into prescribing significantly improved nausea and vomiting control."

Commenting on the findings by email, Dr. David Warr, coauthor of an accompanying editorial, told Reuters Health that the study "was designed to evaluate whether one could achieve better prevention of chemotherapy-induced nausea and vomiting by basing antiemetic prescriptions on patient characteristics rather than just the type of chemotherapy. What their data actually showed was that patient characteristics were not sufficiently powerful to overrule the guidelines."

Despite not being convinced, Dr. Warr, of the University of Toronto, and colleagues concluded that although the study "does not provide evidence that patient risk factors can replace evidence-based guidelines, there is room for research to refine guideline recommendations."

The Canadian Breast Cancer Research Foundation, Ontario Chapter, supported this research. The authors reported no disclosures.

SOURCE: http://bit.ly/1WVYhfc and http://bit.ly/1Qqvpav

JAMA Oncol 2015.