Prevalence of COVID-19 in asymptomatic cancer patients on active systemic treatment in a public Brazilian hospital: The impact of socioeconomic status

ABSTRACT

Background: The COVID-19 pandemic had enormous consequences in Brazil and worldwide. Patients with cancer affected by COVID-19 are at a higher risk of developing complications and worse outcomes compared to a non-cancer population, particularly the ones on active systemic treatment. Considering the COVID-19 high transmissibility in asymptomatic and presymptomatic patients, we sought to determine the prevalence of COVID-19 infection in patients with solid cancers receiving systemic therapy in a Brazilian public health hospital. Furthermore, we interrogated if socioeconomic status (SES) was associated with prevalence. Methods: Consecutive asymptomatic patients undergoing treatment for solid tumors at the chemotherapy and infusion center of Hospital de Base were enrolled. Patients were prospectively tested for SARS-CoV2 RNA real-time polymerase chain reaction with nasal and oropharyngeal swabs immediately prior to treatment. A socioeconomic survey was performed prior to testing. Demographic and socioeconomic characteristics were summarized in means, medians, and proportions. Results: From October 6 to 13, 2020, 148 asymptomatic patients were identified. Of those, 41 were excluded (16 had hematological malignancies, 15 declined testing, 10 were not on active systemic treatment) leaving 107 eligible patients. The mean age of the population was 58 years-old (SD± 12.6);55% were female and 90% were self-identified as White. The most common cancer sites were gastrointestinal tract (37%) and breast (25%). Most patients had metastatic disease (62.9%) and were on a anticancer treatment involving chemotherapy (62.9%). Regarding to SES, 70% of our population had either primary school or were illiterate as their highest educational level. In terms of monthly income, 88% had a personal income inferior to U$390 and 92% a household income inferior to U$585. Of 107 patients tested, only one (0.9%) was positive for COVID-19. This is a 48 years-old man living in an urban area, with primary school educational level and a monthly personal income inferior to U$390. Conclusion: Despite a high prevalence of COVID19 in Brazil, our cohort demonstrated a low prevalence of COVID19 (0.9%) amongst asymptomatic patients with cancer. We hypothesize that patients with cancer, independently of their SES, are aware of the increased risk of developing severe disease and are adherent to physical distancing, masking, and hygiene measures. LF and BB are co-senior authors.