Data from 1016 cancer patients routinely tested for SARS-CoV-2 RNA by nasal or pharyngeal swab and Real-Time PCR (RT-PCR) between 21st March and 4th May 2020 at a large tertiary care hospital in Vienna show a low rate of detectable SARS-CoV-2 infections which was comparable to that of the general Austrian population, but lower than that of non-cancer patients presenting at the same hospital after implementation of institutional and population-wide safety measures. Dr. Matthias Preusser of the Division of Oncology, Department of Medicine I, Medical University of Vienna, Vienna, Austria and colleagues, who published their findings on 14 August 2020 in the Journal of Clinical Oncology, report that their results prove that continuation of cancer care, provision of active anticancer treatment and follow-up visits is feasible and safe in the population of a European capital city affected by the COVID-19 pandemic. Their findings witness that implementation of strict policies is possible and leads to protection of healthcare professionals and patients in a context of cancer care in the setting with a high patient turnover.
The authors wrote in the study background that in line with international data, COVID-19 mortality in Austria is highest in elderly people. However, in order to prevent uncontrolled viral spread, the Austrian government implemented a series of strict measures that successfully led to a significant decrease in infection rate. In their article, the authors analyzed detection rate of SARS-CoV-2 infection in cancer patients treated at a large tertiary care hospital after implementation of institutional and governmental safety measurements. The data were statistically compared to the SARS-CoV-2 prevalence in the Austrian population as determined by a representative nation-wide random sample study and a cohort of non-cancer patients presenting to same hospital.
From 21st March 2020, nasal or pharyngeal respiratory swabs were routinely taken of each patient presenting at their department, unless a negative SARS-CoV-2 test result within the past two weeks was available. In case of symptoms and prior to medical interventions the SARS-CoV-2 test was repeated in a shorter interval. Testing was performed at the Department of Laboratory Medicine, Medical University of Vienna in Vienna by RT-PCR. Comparability of the results of all used test methods were confirmed by participation in international quality control ring trials.
In total, the study team performed 1688 SARS-CoV-2 tests in 1016 patients with cancer; from those patients, majority 560 (55.1%) were undergoing active anticancer treatment in a palliative setting (in most cases early lines of systemic treatment) and 270 patients (26.6%) were undergoing active anticancer treatment in a neoadjuvant/adjuvant setting. Most of the patients (88%) were managed in an outpatient setting.
The authors reported that 53 patients (5.2%) self-reported symptoms that could be potentially associated with COVID-19. However, SARS-CoV-2 was detected in only 4 patients (0.4%). At the time of testing, all 4 SARS-CoV-2 positive patients were asymptomatic and 2 of them had recovered from symptomatic COVID-19. Viral clearance was achieved in 3 of the 4 patients after 14 to 56 days of positive test.
The estimated odds ratio of SARS-CoV-2 prevalence between the cohort of cancer patients and the control cohort of general Austrian population was 1.013 (95% confidence interval [CI] 0.209-4.272; p=1), while between control cohort composed of non-cancer patients presenting at same hospital and the cancer cohort was 18.333 (95% CI 6.056 to 74.157).
COVID-19 experience in terms of infection, death, and recovery rates and pattern differs among countries due to various factors. However, most of the protective measures described by a group of Austrian oncologists, are more or less same as safety measure taken in many other countries, but it seems that Austrian population really respected them. The study team wrote that they feel that their findings are of general relevance, as the need for continuation of care and treatment of patients with cancer, their vulnerability to infectious complications and the high patient turnover are of concern during the COVID-19 pandemic for cancer centres worldwide.
Serological antibody tests were not performed in this study and would be important in future analysis to gain a better understanding of the SARS-CoV-2 immunity status in cancer patients.
Although retrospective, this study provides systematic information on SARS-CoV-2 prevalence in patients undergoing active anticancer treatment. The authors concluded that in their series SARS-CoV-2 detection rate was low in cancer patients with asymptomatic viral carriers detected in only 0.4% of cases. They underlined that implementation of strict safety policies including routine SARS-CoV-2 testing in cancer patients in the cancer centres is advisable to prevent uncontrolled viral spread.
The authors acknowledged support of the Future Operations Clearing Board, SORA and AUSSDA.
Reference
Berghoff AS, Gansterer M, Bathke AC, et al. SARS-CoV-2 testing in 1016 consecutive cancer patients treated at a tertiary care hospital during the COVID-19 pandemic. Journal of Clinical Oncology; Published on 14 August 2020. DOI: 10.1200/JCO.20.01442.