Measuring the impact of guideline-based antiemetic therapy on nausea and vomiting control in breast cancer patients with multiple risk factors.

PURPOSE: The objective of this exploratory analysis was to determine if individual patient risk factors could be used to optimize chemotherapy-induced nausea and vomiting (CINV).

METHODS: Through validated risk prediction models which quantify patient risk factors, 152 patients with early-stage breast cancer scheduled to received adjuvant anthracycline-based chemotherapy were categorized as being at low (level 0) or high-risk (level 1) for CINV. Prior to the first cycle of chemotherapy, low-risk patients received ondansetron and dexamethasone, while high-risk level 1 patients also received aprepitant. For subsequent cycles, patients who experienced CINV had their antiemetics changed in a stepwise manner to level 2 (extended-duration dexamethasone) or level 3 (extended-duration dexamethasone and low-dose olanzapine).

RESULTS: The study enrolled 152 patients who received 484 cycles of chemotherapy. Forty patient cycles were classified as low risk (level 0) compared to 201, 162 and 81 that were classified as high-risk levels 1, 2 and 3, respectively. Complete control of acute and delayed vomiting was comparable and was achieved in over 85 % of patients across all risk levels (p = 0.56 and p = 0.99). In contrast, complete control of acute and delayed nausea was reduced in risk levels 1 to 3 compared to level 0 (acute = 51.2, 58.0, 45.7 vs. 70.0 %; p = 0.013)-(delayed = 32.8, 45.7, 34.6 vs. 62.5 %; p < 0.001).

CONCLUSIONS: Despite the addition of aprepitant, extended-duration dexamethasone and olanzapine, patients at high risk for CINV due to personal risk factors failed to achieve good nausea control.