This study focuses on the population of malignant lymphoma patients who are also in clinical research. Through a real world cross-sectional survey of infection and death risk during the COVID-19 pandemic in Guangzhou from December 2022 to January 2023, this study aims to clarify the risk, level and mortality of lymphoma patients infected with COVID-19 during their clinical research, and provide necessary research data for Chinese lymphoma patients during the COVID-19 pandemic,

Inclusion Criteria:

(1) the diagnosis of lymphoma was confirmed by pathology according to World Health Organization (WHO)-criteria; (2) diagnosed with COVID-19 based on a positive polymerase chain reaction (PCR) test result for SARS-CoV-2 from oropharyngeal swabs, or on a positive detection of covid-19 antigen from nasopharyngeal swabs and typical clinical history; (3) participated in registered clinical trials and received anti-lymphoma treatment within four weeks before COVID-19 infection; (4) complete data on clinico-pathological characteristics, treatment approaches and follow-up were available.

Exclusion Criteria:

• Patients who could not provide detailed information about COVID-19 infection.

This study focuses on the population of malignant lymphoma patients who are also in clinical research. Through a real world cross-sectional survey of infection and death risk during the COVID-19 pandemic in Sun Yat-Sen University Cancer Center from December 2022 to January 2023, this study aims to clarify the risk, level and mortality of lymphoma patients infected with COVID-19 during their clinical research, and provide necessary research data for Chinese lymphoma patients during the COVID-19 pandemic. We also aimed to identify risk factors of moderate/severe COVID-19 infection and hospital admission.