Cancer patients sickened by COVID-19 have higher mortality rate: study
TORONTO -- Cancer patients who have fallen ill with COVID-19 have a higher chance of dying from the disease, according to a new study.
The new study, published Thursday in The Lancet, found that cancer patients with active or previous malignancy who became infected with COVID-19 had a crude death rate of 13 per cent compared to otherwise healthy patients who contract the disease.
"People with cancer face a great deal of uncertainty in the era of COVID-19, including whether the balance of risks and benefits in the treatment of cancer has shifted in some fundamental way," Dr. Jeremy Warner, the study's corresponding author, said in a news release. "The death rate for this group of patients as a whole was 13 per cent, more than twice that reported for all patients with COVID-19. Certain subgroups, such as patients with active cancer and those with an impaired performance status, fared much, much worse."
The data for the study, which is from an ongoing international initiative by the COVID-19 and Cancer Consortium (CCC19), was gathered from 928 patients in Spain, Canada and the United States between March 17 and April 16. Approximately 5 per cent of the study’s participants were Canadian.
The study reported that the cancer-specific factors associated with increased mortality included an active cancer status, particularly progressive cancer, and the presence of one or more additional conditions in patients such as hypertension or diabetes. Another factor was having an Eastern Cooperative Oncology Group (ECOG) performance status of two or worse in measuring how cancer impacts a patient's daily living abilities.
As is the case with the non-cancer population, the study found mortality also increased with age. Mortality was 6 per cent for cancer patients younger than 65, 11 per cent for those 65-74 and 25 per cent for those older than 75. Males also had a higher death rate (17 per cent) than females (9 per cent).
Dr. Brian Rini, one of the study's senior authors, told CTVNews.ca on Thursday that these numbers may increase over time as more patients of various cancer types are studied.
"Of this cohort, which was patients who had a history of cancer, active cancer, some sort of invasive cancer diagnosis who also had a positive PCR test for COVID… 121 out of the 928 patients died in a median of 28 days," Rini said in a phone interview. "But obviously this is just a snapshot in time and some patients had very limited follow up so that number could go up."
However, Rini said the data isn't surprising.
"Worsening cancer is a bad thing, and if you get a bad infection on top of a worsening cancer, then you're in trouble," Rini said. "Probably the biggest thing is that if the cancer was not well controlled, the patient's mortality rate was higher."
Rini said the study does not "represent the entire world of cancer" but does help researchers better understand how COVID-19 impacts cancer patients.
"The data is only from institutions and it's only the patients they entered. Not all cancer patients at these institutions were entered," Rini said. "It was only patients with a history of invasive cancer, but not superficial cancers, so mostly just breast, prostate or bladder cancer."
In addition, the study reported no statistical association between mortality and cancer treatments, suggesting that surgery and chemotherapy can continue during the pandemic with "extreme caution."
"While older patients and those with major comorbid conditions are at substantially increased risk of dying from COVID-19, our early findings are encouraging news for patients without major medical conditions who receive their cancer therapy within four weeks of their infection," Dr. Nicole Kuderer, another lead author on the study, said in the release. "However, more data are needed to reliably assess individual higher risk therapies."
As only the first study in the CCC19's ongoing initiative, Rini said its authors hope to further address COVID-19's impact on different types of cancers and in other subgroups of cancer patients in their forthcoming reports.
"CCC19 has been a massive effort to accumulate clinically-relevant data on a large number of patients with COVID-19 infection. This initial report defines some of the major risk factors and outcomes for certain patient subsets, and several other CCC19 projects are ongoing to further expand this knowledge with the goal to inform cancer patients and providers," Rini said in the release.