Background: Concerns have emerged about the higher risk of fatal COVID-19 in cancer patients. In this paper, we review the experience of a comprehensive cancer center. Methods: A prospective registry was set up at Institut Curie at the beginning of the COVID-19 pandemic. All cancer patients with suspected or proven COVID-19 were entered and actively followed for 28 days. Results: Among 9,842 patients treated at Institut Curie between mid-March and early May 2020, 141 (1.4%) were diagnosed with COVID-19, based on RT-PCR testing and/or CT-scan. In line with our case-mix, breast cancer (40%) was the most common tumor type, followed by hematological and lung malignancies (both 13%). Patients with active cancer therapy or/and advanced cancer accounted for 88% and 69% of patients, respectively. At diagnosis, 79% of patients had COVID-19 related symptoms, with an extent of lung parenchyma involvement ≤50% in 90% of patients. Blood count variations and C-reactive protein elevation were the most common laboratory abnormalities. Antibiotics and antiviral agents were administered in 48% and 7% of patients, respectively. At the time of analysis, 26 patients (18%) have died from COVID-19, and 81 (57%) were cured. Independent prognostic factors at the time of COVID-19 diagnosis associated with death or intensive care unit admission were extent of COVID-19 pneumonia and decreased O2 saturation. Conclusions: COVID-19 incidence and presentation in cancer patients appear to be very similar to those in the general population. The outcome of COVID-19 is primarily driven by the initial severity of infection rather than patient or cancer characteristics.