BACKGROUND: COVID-19 pandemic could create a collateral damage to cancer care denoting disruptions in care due to a significant burden on healthcare and resource allocations. Herein, we evaluate the early changes in the inpatient and outpatient oncology clinics to take a snapshot of this collateral damage at Hacettepe University Cancer Institute. METHODS: Patients applying the outpatient clinic and outpatient palliative care (OPC) clinic for the first time and patients admitted to inpatient wards in the first 30 days after the first case of COVID-19 in Turkey were evaluated. These data were compared with data from the same time frame in the previous 3 years. RESULTS: The mean number of daily new patient applications to the outpatient clinic (9.87+/-3.87 vs 6.43+/-4.03, p<0.001) and OPC clinic (3.87+/-1.49 vs 1.13+/-1.46, p<0.001) was significantly reduced compared with the previous years. While the number of inpatient admissions was similar for a month frame, the median duration of hospitalisation was significantly reduced. The frequency of hospitalisations for chemotherapy was higher than in previous years (p<0.001). By comparison, the rate of hospitalisations for palliative care (p=0.028) or elective interventional procedures (p=0.001) was significantly reduced. CONCLUSION: In our experience, almost all domains of care were affected during the pandemic other than patients' systemic treatments. There were significant drops in the numbers of newly diagnosed patients, patients having interventional procedures and palliative care services, and these problems should be the focus points for the risk mitigation efforts for prevention of care disruptions.