COVID-19 and Cancer

Cancer patients and immunocompromised hosts are particularly susceptible to lung infection. The spectrum of various infectious etiologies ranges widely from viral, bacterial, and fungal pathogens; however, patients’ unique treatment regimens and resulting immunologic deficits predispose patients to particular infections.10-14 In the setting of SARS-CoV-2 and the COVID-19 pandemic, increased emphasis is being placed upon the treatment and protection of those with cancer who may be at increased risk to develop severe and potentially life-threatening respiratory infections.15
Following the COVID-19 outbreak, the Italian National Institute of Health established a surveillance program to collect information on all patients with reverse transcriptase-polymerase chain reaction (RT-PCR) confirmed SARS-CoV-2 infection. Among the Italian population, the overall case fatality rate (CFR) was 7.2% (1625 deaths/22,512 cases) as of March 15, 2020.16 In a subsample of 355 patients, 20.3% were noted to have active cancer in addition to multiple comorbidities.17 Although a higher mean age (79.5 ± 8.1 years) was observed within this cohort, separate analyses have reported a fatality rate approximating 20% in patients aged 80 and older.18 While CFR estimates and degrees of morbidity may vary based upon testing strategies and population demographics, cancer patients and elderly individuals appear at higher risk for adverse outcomes from COVID-19 infection.
Early reports from China indicate that infected cancer patients have a 3.5 times higher risk of requiring ICU admission, mechanical ventilation, or death compared to individuals without cancer.1 Zhang et al. noted a strong association between anti-cancer therapy and risk of severe effects from COVID-19 infection (HR 4.079, p = 0.037) with 6 of 28 (21.4%) COVID-19 patients having received immunosuppressive treatment within the last 14 days.2 In a separate prospective analysis of 1,590 patients with laboratory-confirmed COVID-19 disease, Liang et al. discovered that 18 (1%) patients had a history of cancer, a rate which appears to be higher than the overall cancer incidence within the Chinese population (0.29%) according to 2015 epidemiologic data.1 Of the 16 patients with a known oncologic treatment, 25% underwent surgery or received chemotherapy within the past month. Compared to patients without cancer in this study, oncology patients were older (mean 63.1 years vs. 48.7 years) and more likely to have a history of smoking (22%). Notably, these characteristics are also shared among a large proportion of patients with HNSCC. In a multivariable model, cancer history was associated with the highest risk for severe events (OR 5.4, p < 0.01). Older age, while not significant, was the only risk factor associated with increased risk for severe events in the cancer group (OR 1.43). Critics of this analysis argue that exposure to an infectious source, rather than an association with cancer, is the most important comorbid factor given that 12 of the 18 patients had recovered from their initial cancer treatments (e.g. surgery or chemotherapy) and were without obvious immunosuppression.19 The response, by Wang and Zhang, further notes that a higher median patient age of those with cancer (63.1 vs. 48.7) in addition to increased comorbidities, remain significant factors associated with worse COVID-19 outcomes. These findings have been supported by prior COVID-19 analyses.20-22
Although data regarding the impact of prior viral outbreaks on patients with HNSCC is lacking, the decision to proceed with anti-cancer therapy, including surgery, in the current context of COVID-19 should be carefully considered given the risk of severe respiratory complications, immunosuppression, and death within this cohort. A recent review of 34 asymptomatic patients who underwent various elective surgeries during the COVID-19 incubation period exemplifies these risks.23 All 34 patients went on to develop COVID-19 pneumonia shortly after surgery (median time to COVID-19 onset, 3.5 days), with 15 (44%) requiring ICU admission. Ultimately, half of those (7/15) patients died in the ICU. The risks of treatment delay and impact on tumor progression should be carefully weighed given the potential for devastating outcomes should surgery be pursued, even among asymptomatic patients. Strategies to temporize tumor growth, such as induction chemotherapy, may also predispose to severe COVID-19 complications following immunosuppression. Further, treatment of HNSCC must be balanced with the current local operational environment and resources to achieve maximum patient and staff safety while minimizing morbidity.