ABSTRACT
Background: COVID-19 presents a particular challenge in oncology, as in-person visits and treatments can be delayed during infection and patients are at risk for prolonged viral shedding. Our center uses two consecutive negative PCR tests for patients to return to clinic. As vaccination rates increase, we questioned the need for this strategy vs a time-based clearance approach. Method(s): We identified cancer patients who tested positive for COVID-19 from 10/1/2021 to 3/31/2022 at a single tertiary care center and performed chart review under an IRB-approved protocol. Subgroups were compared using the Welch's t-test and Welch's ANOVA for 2 or > 2 groups, respectively. Result(s): 169 patients were identified. 153 had documented clearance defined as two consecutive negative PCR tests. The mean clearance time was 35.7 days (95% CI 32.3-39.0). There was a trend toward longer clearance time in patients with hematologic vs solid tumors (39.6 vs 33.2, p =.06) and a significant increase in patients treated with B cell depletion (58.0) vs chemo/targeted therapy (35.7, p =.01) or immunotherapy (29.0, p =.004). No significant difference was found by vaccination status or between the Delta and Omicron waves. If defined as one negative test, mean clearance time was 25.9 days (95% CI 23.6- 28.1), and there was a significant difference in patients with hematologic vs solid tumors and in those treated with B cell depletion vs other therapies. However, 16.0% (27/169) of patients had a subsequent positive test after a first negative result, with increased incidence in patients with hematologic malignancy (26.2%, 16/61) and stem cell/adoptive cell transplant (46.2%, 6/13). Conclusion(s): COVID- 19 is a significant barrier to oncologic care, and clearance times remain longer than reported for the general population. In this single center study, clearance time was > 1 month and further increased in patients with hematologic malignancy or on B cell depleting therapy. While adjusting clearance criteria to a single negative test or specific timeframe may be an attractive option to reduce delays, a large proportion of patients may have further positive PCR testing.
ABSTRACT
Background: COVID-19 in oncologic patients presents a clinical dilemma. To reduce the risk of adverse events as well as the risk of exposing others, many institutions have established protocols to define COVID-19 clearance. However, the optimal criteria for discontinuing infection precautions and/or resuming anticancer therapy in COVID-19 patients is unknown. Methods: We identified patients with a positive COVID-19 PCR at a tertiary care hospital between 3/25/2020 and 6/6/2020, and who also had seen an oncologist for a cancer-related diagnosis within the last 3 years. COVID-19 PCR testing was performed using the Abbott Laboratories m2000 platform in conjunction with either the Aldatu Biosciences PANDAA qDxTM SARS-CoV-2 or Abbott RealTime SARS-CoV-2 assays. At our institution, and per current ASCO guidelines, discontinuation of COVID-19 precautions requires two consecutive negative viral PCR tests > 24 hours apart. Results:During the follow-up period, we identified 32 patients with a positive COVID-19 PCR who were receiving active oncology care. Half of this cohort (16/32) had metastatic disease at the time of COVID-19 diagnosis. 17 patients were on active treatment at time of COVID-19 diagnosis (8 receiving cytotoxic chemotherapy). Among patients who met criteria for COVID-19 PCR clearance, median time to clearance was 37 days (range, 10-58 days). When accounting for censoring at the time of last COVID-19 assay, median time to clearance for all patients was estimated at 50 days. 14 patients resumed anticancer treatment prior to COVID-19 clearance (5 received cytotoxic chemotherapy), requiring substantial allocation of staff and resources for safe treatment isolated from other oncology patients. Among the 13 patients who met clearance criteria, 2 subsequently had a positive COVID-19 PCR after resumption of treatment. We explored COVID-19 clearance time under an alternative symptom/time based strategy based on CDC criteria (at least 10 days after first positive PCR and 3 days after last day of symptoms). Under this strategy, median time to COVID-19 clearance would be 14 days. Conclusions: In patients with cancer who develop COVID-19 infection, viral shedding can persist for many weeks after disease onset, but the implications of this shedding on likelihood of infection is unknown. Treatment of COVID-19 positive oncology patients requires substantial planning and resources. Test-based versus symptom/time-based strategies for determining discontinuation of precautions and resumption of treatment should be further investigated to provide safe and effective care.