In late March of 2020, Melvin LK Chua, MBBS, FRCR, PhD, from the division of radiation oncology and medical sciences at the National Cancer Centre Singapore, and coauthors concluded that patients with cancer were at a 2.3-fold higher risk of COVID-19 compared with the general population, with older lung cancer patients at particular risk. He also noted that modifying the diagnostic criteria for COVID-19 — to include a positive computed tomography (CT) finding of atypical pneumonia — helped aggressively contain new and suspected cases of infection in Wuhan.

Cancer Therapy Advisor spoke to Dr Chua about why he thought CT could be a good testing method to supplement polymerase chain reaction (PCR) testing and how compared with CT, the use of nasopharyngeal swabs for reverse transcription-polymerase chain reaction (RT-PCR) testing may actually be a riskier procedure than the use of CT. In addition, he spoke about how he and his coauthors have papers under review that seek to answer whether concurrent or recent administration of immune checkpoint blockade therapies could worsen COVID-19 illness trajectories.

Cancer Therapy Advisor (CTA): A recent study found that an asymptomatic patient with a history of lung cancer presented with radiological CT patterns typical for COVID-19 and with positive fludeoxyglucose (FDG) uptake. Do you think this supports an argument in favor of the proactive testing for the presence of infection across all patients with a history of lung cancer who have a CT scan typical for COVID-19?

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Dr Chua: Certainly, a stratified manner of testing is required given the limited testing capacity globally. Our group and others have previously shown that CT is a good method to supplement PCR testing, given the high false-negative rate of the latter. I believe the vice versa is also true — to do PCR testing if diagnostic CT picks up suspicious findings.  To clarify, we are not suggesting that CT replaces PCR here.

Patients should also be isolated/quarantined while waiting for the test results! 

CTA: Recently published papers1,2 have seemed to suggest that the use of CT scans for diagnosis of COVID-19 could put radiologists at increased risk of infection. What is your view on this position? Should CT scans be a diagnostic plan B?

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Dr Chua: I don’t think radiologists are at an increased risk of infection relative to health care workers from other ambulatory clinical services. Importantly, the focus should be on implementing tight infection control measures at any ambulatory clinical facility to protect [health care workers] in the background of an outbreak. In fact, compared to CT, [the use of] nasopharyngeal swabs for RT-PCR testing is a riskier procedure to the individual performing the swab.

We currently have a paper under review that describes the low infection risk to patients and [health care workers] with good infection-control measures in a cancer center from Wuhan. Such evidence is needed in order to assess the effectiveness of these best practices.

CTA: There will be data presented at the American Association for Cancer Research (AACR) 2020 virtual meeting on the TERAVOLT trial. Are you familiar with this study and what it seeks to answer? And, what do you expect will be the outcomes from this analysis?

Dr Chua: Yes I am familiar with the study. In fact, we are part of another multicenter effect [study] in head and neck cancer: HERODOTUS; principal investigators are Amanda Psyrri, MD, and Lisa Licitra, MD, PhD. [Editor’s note: this trial has yet been listed on, but Dr Chua confirmed that the Head Neck Cancer International Group (HNCIG) is in the process of recruiting trial sites, and funding for the trial has been secured].

In essence, what these global consortiums seek to do is to aggregate data on cancer patients who unfortunately contract COVID-19 either during their treatment or during follow-up. Such efforts are necessary to pool data so that robust analyses of outcomes, and association of relevant factors (eg, cancer types, treatments) with outcomes can be performed. That way, guidelines and management of cancer patients can be guided better by evidence, as opposed to sentiments or consensus agreements between physicians.