In a study examining hospital-acquired transmission of severe adult respiratory syndrome coronavirus 2 (SARS-CoV-2) at a medical institution in Wuhan, China, researchers found that the cumulative incidence of COVID-19 for those with cancer was higher than the incidence reported for the entire city of Wuhan during the same period.
At Zhongnan Hospital of Wuhan University, Hubei, the infection rate of SARS-CoV-2 in patients with cancer was 0.79% (12 of 1524 patients with cancer; 95% CI, 0.3%-1.2%) — higher than the disease incidence reported in the community during the study time (odds ratio [OR], 2.31; 95% CI, 1.89-3.02).
Researchers reviewed data and records of the 1524 patients with cancer who were admitted to the department of radiation and medical oncology at the institution from December 30, 2019, to February 17, 2020 (the data cutoff date). The median age of infected patients was 66 years (range, 48-78 years), and 8 of the 12 infected patients with cancer (66.7%) were older than 60 years.
Five of the 12 infected patients (41.7%) were being treated with chemotherapy with or without immunotherapy (3 patients) or radiotherapy (2 patients). Notably, fewer than half of the 12 patients with cancer who were infected with SARS-CoV-2 were undergoing active treatment for their malignancies.
Three of the 12 patients (25%) developed SARS, 1 of whom required intensive care. As of March 10, 2020, 6 patients (50%) had been discharged from the treatment facility, and 3 of the patients with both cancer and COVID-19 had died.
Strikingly, patients with NSCLC appeared to be at the highest risk for contracting COVID-19: Seven of the 12 infected patients with cancer (58.3%) had non-small cell lung cancer (NSCLC). The other cancers represented in the retrospective analysis included rectal, colon, pancreatic, breast, and urothelial cancers.
Additionally, patients with NSCLC who were older than 60 years were found to have a higher incidence of COVID-19 than those 60 years or younger (4.3% vs 1.8%, respectively). Although a prior study cited by the authors found that patient age was not associated with susceptibility to COVID-19 infection, larger prospective studies may be able to resolve and/or explain any associations between age and disease susceptibility, the authors wrote.
Perhaps unsurprisingly, the researchers found that patients with cancer living in “the epicenter of a viral epidemic harbored a higher risk of SARS-CoV-2 infection” than the general population of Wuhan.
According to study coauthor Melvin L.K. Chua, MBBS, PhD, from the division of radiation oncology at the National Cancer Centre Singapore, the incidence of COVID-19 in patients with cancer remains higher than in the general community, even after the data cutoff date of February 17, 2020. However, he explained to Cancer Therapy Advisor in an email, in the city of Wuhan, “the overall number of new cases sharply declined right after February 18, and [this] remains the case to date, where there are no new cases apart from imported cases from abroad.”
Dr Chua also explained that due to the high false-positive rate of the polymerase chain reaction (PCR) test that was being used to detect the virus within the community — and as a result of a shortage of test kits — on February 8, 2020, the diagnostic criteria for COVID-19 was revised. Starting on this date, a positive CT finding of atypical pneumonia was sufficient to diagnose COVID-19. This change in criteria was made in an effort to aggressively contain the new and suspected cases in Wuhan, the epicenter of the outbreak.
“Hence, this led to an acute spike in new cases in Wuhan after February 8, but it was also a pivotal moment in terms of containing the transmission of this disease,” noted Dr Chua. “Thus, we believe the 2-fold higher risk of COVID-19 in cancer patients is probably a modest estimate, rather than an overestimate.”
Ultimately, the researchers concluded that for patients with cancer, going to the hospital at all — as well as returning for multiple visits — could be risk factors for SARS-CoV-2 infection. They noted that during viral epidemics, “aggressive measures” must be undertaken to reduce infection transmission. Specifically, Dr Chua wrote, oncologists should take action to limit follow-up visits of well patients and other hospital visitors, as well as be conscious of the risks associated with immunosuppressive treatments such as transplantation and chemotherapy.
“There seems to be a specific linkage between lung cancer patients and COVID-19 risk,” Dr Chua added, “thus, extra precautions ought to be taken for these patients.”
Yu J, Ouyang W, Chua MLK, Xie C. SARS-CoV-2 transmission in patients with cancer at a tertiary care hospital in Wuhan, China [published online March 25, 2020]. JAMA Oncol. doi: 10.1001/jamaoncol.2020.0980