Clinical Screening for COVID-19 in Asymptomatic Patients With Cancer

This quality improvement study examines the efficacy of a repeated testing protocol for coronavirus disease 2019 (COVID-19) among patients with cancer.


Introduction
As the coronavirus disease 2019 (COVID-19) pandemic continues across the United States, a critical issue for practicing oncologists is how to continue cancer care while protecting patients. 1 To continue care for patients while also minimizing exposure to health care staff, the Weill Cornell Medicine Division of Hematology and Medical Oncology created separate units for patients with confirmed COVID-19, patients with symptomatic but unconfirmed COVID-19, and asymptomatic patients with no known high-risk COVID-19 exposures. 2 Patients were contacted prior to their appointment and triaged based on their COVID-19 risk status. To understand the success of our clinical screening and triaging procedures, we implemented a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing protocol in asymptomatic patients who required cancer care across the Division of Hematology and Medical Oncology.

Methods
This quality improvement study, approved by Weill Cornell Medicine, follows the Standards for Quality Improvement Reporting Excellence (SQUIRE) reporting guideline. Informed consent was waived because data were deidentified, per institutional policy.
Patients were considered asymptomatic if they had no recent fever (defined as body temperature Ն100.5°F for Ն5 days); no COVID-19 symptoms, which included cough, headache, loss of taste, and shortness of breath 3 ; or high risk exposure (eg, contact with an individual with confirmed COVID-19, nursing home stay, or hospitalization) within 14 days. Diagnosis of COVID-19 was confirmed using SARS-CoV-2 nasal swab polymerase chain reaction (PCR) testing (Cobas 6800; Roche Diagnostics) and SARS-CoV-2 IgM and IgG serological tests (Pylon 3D; ET HealthCare). 4 Patients were retested every 1 to 2 weeks. Rates of positive SARS-CoV-2 PCR and COVID-19 serological tests and 95% CIs are reported, using the 2-sided Clopper-Pearson (exact) 95% CI.
Statistical analyses were conducted using Stata statistical software version 13.1 (StataCorp).

Results
From April 30 through June 2, 2020, we performed 621 SARS-CoV-2 PCR tests on 537 asymptomatic patients (272 [50.7%] men) with hematologic or solid tumor malignant neoplasms ( Table 1). Our patients were geographically representative of New York, New York, and surrounding areas, and more than 90% of patients were receiving active cytotoxic or targeted therapy. The rate of SARS-CoV-2 positivity was 0.64% (95% CI, 0.18%-1.64%). This includes 84 patients who had repeated SARS-CoV-2 tests, all of which were negative. Only 4 asymptomatic patients had test results positive for COVID-19, 2 each for hematologic and solid tumor neoplasms. We also performed serological tests from May 18 to June 2, 2020, on 238 asymptomatic patients. The rate of COVID-19 prior exposure in our asymptomatic cancer population was 4.23% (95% CI, 2.05%-7.65%) ( Table 2). Notably, during this period, the SARS-CoV-2 PCR positivity rate in New York City in early May was 20%. 5

Discussion
The findings of this quality improvement study have several important implications. While it was clearly prudent to postpone elective procedures and delay care when possible, it is also clear that the risk of COVID-19 is likely to persist for some time. Cancer care will need to continue, given that further delays will lead to significantly worse outcomes for individual patients 6 and other health care crises.
We observed that the rate of past infection in our clinically screened asymptomatic cancer population