Association between the site of emergency care and patient-centered outcomes in patients with cancer: rationale and design of the French COVER cohort.

Abstract

Patients living with cancer now account for a substantial and growing share of emergency department (ED) visits and carry a high burden of hospitalization and in-hospital death. Their acute presentations are frequently multifactorial - driven by disease progression, treatment toxicity, immunosuppression, or the decompensation of comorbid conditions. They may present with higher rates of complications because of novel therapies, such as immune checkpoint inhibitors and cellular therapies, whose emergency manifestations remain unfamiliar to many emergency physicians. Despite this growing importance, the unscheduled care of patients with cancer has received comparatively little dedicated research. How these patients are managed in the ED, how often the emergency physician can access the oncology medical record and goals of care, how the acute complications of new anticancer therapies present, and how a background of cancer should modify the diagnostic approach to everyday emergencies remain poorly characterized. To address these gaps, the Cohort of Onco-hematologic patients visiting the Emergency depaRtment was designed as a prospective, multicenter French cohort of consecutive adults with active cancer or in remission for less than 1 year, presenting to the ED for any reason. Enrollment took place across a national network of 76 EDs for two 1-week periods (summer 2025 and winter 2025-2026), with follow-up to 90 days, yielding a large sample of patients designed as a platform for multiple analyses. The primary aim of Cohort of Onco-hematologic patients visiting the Emergency depaRtment is to determine whether being managed in an ED located within the patient's own cancer referral center, rather than any other hospital, is associated with improvement in morbidity and mortality, captured by the number of days alive and out of hospital at 30 days. Beyond this primary aim, the cohort will support a broad research program on the place of the ED in the cancer care pathway, from patient profiling and pathway description to the emergency toxicities of anticancer drugs and the cancer-specific features of common presentations.