CONTEXT Key Objective What was the impact of COVID-19 pandemic on cancer care at a global level? How did the magnitude of impact vary in different settings? Knowledge Generated Our study revealed that the overwhelming majority (88%) of the 356 participating centers on six continents faced challenges in providing usual cancer care for many reasons, including precautionary measures, an overwhelmed health care system, lack of personal protective equipment, and staff shortage. More than a third of these centers reported patient exposure to harm from interruption of cancer-specific care or other medical care. As expected, the impact was more pronounced in low-income countries. The implementation of virtual communication and remote care were prevalent responses in most centers. Relevance The lessons learned from this study may help oncology centers to manage the current pandemic more efficiently and be better prepared for any future crises.