Cancer patients with COVID-19 are much more likely to die due to novel coronavirus infection than those without the malignant disease, according to a study led by an Indian-origin researcher who says the findings may help protect this vulnerable section of the global population.
The study, published in the journal Cancer Discovery, is the largest so far to assess outcomes for patients with cancer who have also been infected with COVID-19, according to the researchers.
"Our findings emphasise the need to prevent cancer patients from contracting COVID-19 and -- if they do -- to identify and closely monitor these individuals for dangerous symptoms," said Vikas Mehta, a co-lead author of the study from Albert Einstein College of Medicine in the US.
"We hope that our findings can inform states and communities that have not yet been so severely struck by this pandemic about the unique vulnerability cancer patients face," Mehta added.
In the study, the scientists assessed 218 cancer patients who tested positive for COVID-19 from March 18 to April 8 at the Montefiore Medical Center in New York City, US -- one of the worst hit regions by the pandemic in the country.
They found that a total of 61 cancer patients died from COVID-19 -- a dramatically high case-fatality rate of 28 per cent.
In comparison, they said, the mortality rate for COVID-19 in the US is 5.8 per cent, according to the World Health Organization (WHO).
"A key element is that mortality appears to be more closely related to frailty, age, and co-morbidities than to active therapy for cancer," said co-senior author Balazs Halmos from Einstein College of Medicine.
"Our data suggest that we should not stop lifesaving cancer therapies, but rather develop strategies to minimise potential COVID-19 exposures and re-evaluate therapies for our most vulnerable cancer populations," explained Amit Verma, co-senior author of the study.
According to the researchers, the time period during which these patients were treated was earlier in the epidemic when testing was almost exclusively done in sicker, symptomatic patients who required hospitalization.
They said this may partially explain the high fatality rate within the study's cancer population.
However, even when compared to mortality rates in non-cancer patients at Montefiore and across New York City during the same time period, the study noted that cancer patients demonstrated a significantly higher risk of dying from COVID-19.
As a group, COVID-19 patients with hematologic (blood) cancers, such as leukemia and lymphoma, had the highest mortality rate of 37 per cent (20 of 54 patients), the scientists said.
And for patients with solid malignancies, they said the mortality rate was 25 per cent (41 of 164).
The researchers reported some striking differences among specific solid cancers in the study.
They said the mortality rate for patients with lung cancer was 55 per cent, and for those with colorectal cancer, it was 38 per cent, compared with mortality rates of 14 per cent for breast cancer, and 20 per cent for prostate cancer.
According to the study, certain underlying conditions such as older age, hypertension, heart disease, and chronic lung disease were significantly associated with increased mortality among cancer patients with COVID-19.
More than half of those with cancer who died due to COVID-19 (37 out of 61 patients) had been in places with a higher risk of exposure to the novel coronavirus, such as nursing homes, hospitals, or emergency departments within the 30 days before being diagnosed with the highly contagious disease.
The scientists said this period was before widespread social distancing had been implemented.
Citing the limitations of the study, the researchers said they could not fully account for all of the patients’ pre-existing health conditions prior to COVID-19 infection.
Differential treatments paradigms for COVID-19 infection were also not controlled for in the study, the scientists said.
"We also acknowledge that the mortality rate is highly dependent on the breadth of testing, and therefore understand that more widespread detection of viral infection would likely alter the results," they wrote in the study.
The researchers believe that further studies assessing a larger population of cancer patients with more rigorous control for other factors may help validate the findings.
"These data suggest the need for proactive strategies to reduce likelihood of infection and improve early identification in this vulnerable patient population," they concluded in the study.