Coberly, Tammy Bratton

11595 Background: In 2017, NCCN (2/2017) and ASCO (8/2017) each amended antiemetic guidelines to classify carboplatin AUC ≥4 as highly emetogenic chemotherapy (HEC), recommending upfront triple prophylaxis with an NK1 receptor antagonist (RA) + 5HT3 RA + dexamethasone. Physician concordance with the new recommendations, and the consequences for avoidable post-chemotherapy acute care, merit study. Methods: In a large electronic health record database (IBM Explorys), we identified carboplatin courses of therapy (≥14-day cycles as a proxy for AUC ≥4) and courses with ≥7-day cycles of other HEC and non-HEC therapy from 4Q 2012 through August 2018. Guideline concordance, defined as triple prophylaxis at HEC initiation, was evaluated. We also assessed 30-day post-chemotherapy acute care (inpatient or emergency department) associated with nausea or vomiting (NV) or eight other toxicities deemed avoidable in the US Centers for Medicare & Medicaid’s new oncology outcome measure OP-35. Results: 11,554 carboplatin courses were identified. Before the guideline change, rates of upfront triple prophylaxis grew from 14% in 2013 to 16% in mid-2017. Rates then rose to 26% by 1Q 2018 before dropping to 21% by 3Q 2018; quarterly rates averaged 20% (range 15%-26%) following the guideline change. In 31% of carboplatin courses we noted 30-day acute care use, of which 75% involved ≥1 of the ten OP-35 toxicities. NV (with or without acute care use) was reported in 24% of courses, and 27% of total OP-35 acute care events involved NV. Rates for NV, and for OP-35-related and NV-related acute care after carboplatin, were similar to rates after other HEC chemotherapy, and higher than rates after other non-HEC IV chemotherapy or oral HEC/MEC agents. Conclusions: Use of upfront triple antiemetic prophylaxis has increased only marginally for carboplatin AUC ≥ 4 since its 2017 re-classification as HEC in national guidelines, perhaps due to low awareness of the change. Patients receiving carboplatin had similar rates of NV and related 30-day acute care events as seen for other HEC, confirming that the new HEC definition fits clinical experience. More triple prophylaxis use is needed to reduce NV and NV-related avoidable acute care seen with carboplatin AUC ≥ 4.

PURPOSE: After ASCO and National Comprehensive Cancer Network guideline recommendations for triple antiemetic prophylaxis for carboplatin area under the curve (AUC) ≥ 4, and the publication of studies documenting avoidable acute care after chemotherapy involving nausea and vomiting (NV) and other toxicities, we studied clinician adherence to the guideline change and assessed avoidable acute-care use. METHODS: Using a large electronic health record database, we evaluated antiemetic prophylaxis as recommended in the guidelines and post-chemotherapy avoidable acute-care use (defined as involving any of NV or 8 other toxicities) for patients initiating carboplatin or other chemotherapy from October 2012 to August 2018. RESULTS: We identified 11,554 carboplatin courses. After the guideline change adding neurokinin-1 receptor antagonists (RAs) for carboplatin AUC ≥ 4, its use rose to 20% of courses from the prior average of 16%; virtually all courses also included a 5-HT3 RA plus dexamethasone. We found avoidable acute care in 23% of courses; one quarter of these events were associated with NV. Acute care rates after carboplatin mirrored those after other highly emetogenic chemotherapy or oxaliplatin and exceeded those after other chemotherapy regimens. The > 80% shortfall in adherence may have been caused by low awareness or acceptance of the guideline change and/or by poor awareness of avoidable acute-care use after carboplatin. CONCLUSION: Neurokinin-1 RA prophylaxis for carboplatin AUC ≥ 4 remains low and largely unchanged despite National Comprehensive Cancer Network and ASCO 2017 recommendations for inclusion. NV and avoidable acute care involving NV seen after carboplatin were consistent with other highly emetogenic chemotherapy. Clinician action is required to remediate incomplete prophylaxis and to no longer place patient outcomes, resources for cancer treatment, and clinician reimbursement at risk.