Effect of COVID-19 pandemic lockdowns on planned cancer surgery for 15 tumour types in 61 countries: an international, prospective, cohort study

COVIDSurg Collaborative, Global Initiative for Children's Surgery, GlobalSurg, GlobalPaedSurg, ItSURG, PTSurg, SpainSurg, Italian Society of Colorectal Surgery, Association of Surgeons in Training, Irish Surgical Research Collaborative, Transatlantic Australasian Retroperitoneal Sarcoma Working Group, Italian Society of Surgical Oncology