The Incidence of Clinical Covid-19 Infection in Patients Undergoing Radiotherapy During the Two First Waves in a University Hospital in Iran

Background and Objective: During the COVID-19 epidemic, concerns about cancer patients undergoing radiotherapy have increased because of the numerous hospital visits, which may increase the risk of contracting COVID-19. We aimed to investigate the incidence of COVID-19 among patients visiting our radiation oncology department during the first and second peaks of the epidemic. Methods: In this cross-sectional study, we included all patients who underwent radiotherapy from November 2019 to September 2020. We contacted the patients and asked if they had COVID-19 during this time and how they were diagnosed. Clinical signs and a positive PCR test were acceptable as COVID-19 diagnostic criteria. We also gathered cancer and treatment status data from the patients’ records in the ward medical library. This study was approved by the institutional review board and ethics committee (code: IR.TUMS.VCR.REC.1399.104). Results: During the study period, 687 patients were admitted to our radiation oncology ward. The patients’ median age was 55 (IQR: 44-65), of whom 424 (61.7%) were females. Twenty-three (3.3%) patients developed COVID-19, 15 (65.2%) of whom were diagnosed with clinical symptoms and 8 (34.8%) with PCR. Twelve and 11 patients contracted COVID-19 in the first and second epidemic peaks, respectively. Even though no patients with skin cancer or sarcomas of the bone or soft tissue contracted COVID-19, the highest frequency of COVID-19 was seen among patients with intrathoracic or lung cancer with 38 times the odds of patients with head and neck cancer to develop COVID-19. Highly susceptible patients were those with hematologic and upper gastrointestinal (GI) and gynecologic cancers, respectively. We found a significant association between intrathoracic (mainly lung) cancers and infection with COVID-19 (P-value = 0.02). Conclusion: Patients undergoing intrathoracic cancer radiotherapy are at a higher risk of developing COVID-19. We believe these patients should be prioritized in cancer patients’ screening, case-finding, or vaccination programs.