PURPOSE: Referrals to the Emergency Department can be distressing to patients with advanced cancer and may be a non-optimizing health care service. We aimed to describe the appropriateness and potential avoidability of Emergency Department referrals in a tertiary cancer care center where only physician referrals are allowed. METHODS: We prospectively reviewed the electronic medical charts of patients consecutively checked into the Emergency Department in August 2015. The appropriateness of referrals was assessed using a nationally validated classification (Classification Clinique des Malades aux Urgences) and local criteria. Potentially avoidable referrals were assessed using international classifications (Institute for Healthcare Improvement State Action on Avoidable Rehospitalizations diagnostic tool according to Kosecoff's criteria) and local criteria. RESULTS: We included 500 referrals related to 423 patients. The mean age was 59 years, and 74% of cancers were progressive. The referrals were appropriate in 61% of cases. They were deemed potentially avoidable "with a high likelihood" in 33.4% (CI95% [29.3-37.5]) of cases, potentially avoidable "with a moderate likelihood" in 14.4% (CI95% [11.3-17.5]) of cases, and "non-avoidable" in 52% (CI95% [47.6-56.4]) of cases. Opportunities to avoid referrals after an index stay involved this hospital stay or discharge process in 66 cases (28%), the follow-up period in 59 cases (25%), or both in 66 cases (28%). CONCLUSIONS: Potentially avoidable ED referrals are common in patients with cancer. These potentially avoidable ED referrals underline the importance of several domains of care coordination. Comment in Response to "Identification of appropriate and potentially avoidable emergency department referrals in a tertiary cancer care center" by Duflos et al. [Support Care Cancer. 2018] Response to the response by Lahbib et al. to "Identification of appropriate and potentially avoidable emergency department referrals in a tertiary cancer care center" by Duflos et al. [Support Care Cancer. 2018]