Predictive factors of delayed viral clearance of asymptomatic Omicron-related COVID-19 screened positive in patients with cancer receiving active anticancer treatment.

Objectives: We sought to identify the predictors of delayed viral clearance in patients with cancer with asymptomatic COVID-19 when the SARS-CoV-2 Omicron variants prevailed in Hong Kong.

Methods: All patients with cancer who were attending radiation therapy for head and neck malignancies or systemic anticancer therapy saved their deep throat saliva or nasopharyngeal swabs at least twice weekly for SARS-CoV-2 screening between January 1 and April 30, 2022. The multivariate analyses identified predictors of delayed viral clearance (or slow recovery), defined as >21 days for the cycle threshold values rising to ≥30 or undetectable in two consecutive samples saved within 72 hours.