What research tells us about coronavirus and cancer

Woman wearing face mask

Making sense of what research tells us about coronavirus, particularly as it pertains to cancer.

In a few short months, we have come through some of the most radical changes in our lives that our community as a whole will likely ever experience.  For most of us, this also means we have been inundated with a vast and often confusing array of information so we thought we’d try and make some sense of what research tells us about coronavirus, particularly as it pertains to cancer.

What is COVID-19 and how is it picked up?

Corona viruses are quite common viruses affecting humans and animals.  These viruses pass from one animal to another in invisible droplets as animals breathe, interact with each other and especially cough or sneeze in company, and can (thankfully very rarely) pass from animal to human as has happened in the case of COVID-19.

Coronavirus infection is usually picked up by someone breathing in droplets spread by an infected person, either through speaking in close proximity or sneezing/coughing, and infection may also possibly be picked up from droplets that land on surfaces which can be transferred from the hands to the nose, mouth or eyes but this type of transmission is less certain.

Why is coronavirus especially important for those being treated for cancer?

In the majority of those infected, symptoms range from showing no symptoms, through mild colds or more serious flus which recover after a couple of weeks.  However, for others the infection can be deadly and, for some, infection can trigger more chronic health concerns, including lung damage and chronic immune system problems.  Simply put, the most common indicator as to the level of risk of someone becoming seriously ill or dying is their “frailty”, albeit, younger people can and have died from the disease. 

Frailty can arise as we get older or if we have certain underlying conditions, especially those which undermine the immune system, breathing or the circulation of blood around our body.  As we age, these diseases become much more common and they can happen together.  Those diagnosed with cancer are often older and have increased chances of having these other illnesses and less active immune systems. 

Certain cancer treatments, especially chemotherapy and major surgery can also reduce the effectiveness of the immune system.

If our lungs or blood flow around our body are weakened by existing diseases, the virus is also much more likely to have serious consequences. 

Currently, despite claims to the contrary, there are no proven treatments to prevent infection and the path to an effective vaccine being produced remains uncertain.

Because those being treated for cancer, as well as those who are older and/or have other conditions are inherently more susceptible to the impacts of coronavirus infection, and with no treatments, preventing people passing on or catching the virus is the only route to block those being treated with cancer from the dangers of uncontrolled infection.

Who is most at risk?

The risk of COVID illness therefore vary across different cancer populations.  Those most at risk include people whose immune system is weaker.  So, this includes those on intense cancer treatments, recent stem cell transplants,  2-3 weeks after chemotherapy or major surgery, those who are older (especially those over 70); certain types of cancer that reduce the effectiveness of the immune system, such as certain blood cancers, and those on longer-term treatments that may modify the effectiveness of the immune system.  Those with other underlying illnesses (in addition to their cancer) such as diabetes, breathing problems, heart disease and kidney disease.  

The HSE recently published a breakdown of the underlying illnesses recorded among those who died from COVID illness (to 17 June 2020).

Of 1389 deaths where information on pre-existing conditions was available, 42% had chronic heart disease, 31% had chronic neurological disease, 17% had chronic respiratory disease.  15% had cancer and 14% had diabetes (note individuals can have more than one of these conditions at the same time).

Since the greatest risk of infection occurs from close contacts – especially home or healthcare environments, family members have also had to take extra precautions to ensure that they do not risk passing on the infection to their loved ones being treated for cancer.

What are the best ways to protect against infection?

Methods to protect from infection are aimed at reducing the risk of contracting the virus.

  1. With droplets being the major route of infection, isolation from others who might have the illness is the most powerful single method to stop an individual acquiring infection. However, such isolation is hugely difficult and painful for everyone, as well as posing practical challenges around day to day life, such as getting food and accessing healthcare.
  2. Reducing the level of infection in the wider community is very important to reduce the risk of an individual getting infected. Hence, most nations introduced draconian measures to greatly curb interactions among people. Such measures are very effective but cause massive economic, societal and cultural damage and can only be used for a short period. Analysis provided to NPHET suggests that without the introduction of such mitigations, new coronavirus infections in Ireland would have peaked at approximately 100,000 per day in April with thousands of deaths per day and an overwhelmed health service.  
  3. Putting greater distance between ourselves and others greatly reduces the chances of becoming infected from someone else. Hence, social distancing (physically staying away from others and from crowded areas) is also very effective although this makes several aspects of normal life difficult, if not impossible. Since, under calm air conditions, droplets can readily travel at least 1 metre from an infected person, giving a greater distance provides the lowest risk barrier, where achievable (for example in queues).
  4. Humans very commonly touch areas of their faces where infection could be transmitted further into the body. Hence, regular hand washing is important to reduce the possibility that something we touch could introduce infection. 
  5. Masks are useful as a barrier for protecting people around the wearer, but those wearing the masks are not necessarily as protected from infection themselves and so should still take all the other precautions that they normally would. Current guidance is to use cloth-based face coverings in situations of high public contact (such as public transport and in retail outlets - now mandatory), with disposable surgical masks only required in more close contact medical-type situations. Proper fit and use of masks is also essential and those less used to them may benefit from having someone show them how to make a good seal around the nose and mouth.

    See this visual for guidance on how to wear a mask and help ensure that it is giving the maximum potential possible – an incorrectly worn mask may give no protection against virus transmission.

What are the knock-on effects of Coronavirus from a cancer perspective?

Worry about the effects of the disease, the need to stop it spread and the need to prepare our health system for a potential massive amount of illness (as happened and is happening in some parts of the world) led to major disruptions of cancer diagnosis, treatment and after care.


Screening (looking for hidden signs of cancer among people who don’t have any signs) was stopped. Doctors changed some forms of treatments to make them less likely to be vulnerable to COVID illness, so some cancers were treated immediately with radiotherapy instead of surgery. Screening services are now returning on a phased basis which will continue over the coming weeks and months.

Symptomatic presentations

Thankfully, the amazing work of our community and healthcare professionals meant that those showing overt signs of cancer were managed and supported through this time. For a short time, it became difficult and worrisome to contact GPs but they rapidly adapted to be able to manage patient issues. Unfortunately, a sizeable number of people did not contact their doctor about worrisome health symptoms that could be indicative of cancer (eg pains, weight loss, unusual bleeding etc) due to concerns over getting coronavirus, and such people continue to be encouraged to contact a healthcare professional to have their symptoms checked out.

Treatment & aftercare

The nature of care also changed with hospital admissions being screened before they came in, no accompanying persons being allowed etc. Many patients saw delays, postponements or cancellations of their usual routines as well as many follow up appointments being delayed and/or being conducted over the phone instead of in person.  

For people with advanced cancers, some were recommended not to continue treatment due to the risks involved. Terminal care became delivered in a more isolated manner (intended to reduce any chances of passing on COVID), with restrictions on visitors, extensive use of PPE etc. Hospitals also underwent massive changes in how they deliver cancer care, with most units physically moving either on the hospital campus or to the private hospitals which were leased to provide capacity. 

Through the amazing support of our volunteers and nursing staff, the Society was able to maintain patient transport activities and night nursing throughout and these services remain in higher demand than they were before COVID.

The net effect of these changes has been dramatic. All cancer clinics are now delivering routine follow-up care remotely, where possible. In other words, they are using phone or video calls to discuss patient issues. For those coming into hospitals for aspects of care, all are routinely screened for possible COVID symptoms/exposure before they enter the hospital and large communal waiting rooms disbanded.

While all urgent cases are being treated very rapidly (through rapid access clinics), postponements and less people initially presenting with cancer symptoms have led to some backlogs of people waiting for scans and treatment commencement. Hence, all hospitals are currently trying to prioritise from a much larger volume of people needing to be seen than normal. This is confusing and upsetting for many people with cancer worries.

We have recently spoken to two cancer specialists about these issues, and the interviews may give some additional information for those who have worries at this time.

Dr Richard Bambury on changes to cancer treatments during coronavirus

Professor Donal Brennan on cancer treatment during coronavirus

We are fortunate that treatment and care of cancer has been able to continue throughout this initial COVID emergency. The challenge is to maintain the good quality cancer care we need while we live with the ongoing challenges of COVID. Delays to waiting lists will continue to be an issue for cancer patients over the coming months as services continue to work through a backlog of cancelled and delayed procedures and appointments while also dealing with new cases of cancer diagnoses occurring every day.

The tremendous anxiety that cancer issues bring can be added to by the difficulty of isolation and cocooning, brought in to reduce the chances of infection among those most vulnerable in our community.

The Society continues to offer help and support for anyone with worries or concerns about cancer and COVID through its Freephone Support Line service on 1800 200 700, as well as through information and supports available on our website. 

Many of those impacted by cancer are facing an even greater burden and isolation at this time.  We can all play our part by supporting each other, especially those with cancer worries, but also by helping continue to play our part in “flattening the curve” by adhering to public health advice and thereby insulating those most vulnerable from the ongoing risk of becoming infected.  This is as important now as it was at the outset of this crisis.

Contact the Irish Cancer Society Support Line

If you have worries or concerns about cancer, you can speak confidentially to an Irish Cancer Society Cancer Nurse through the Freephone Support Line on 1800 200 700.

Monday to Friday, 9.00am - 5.00pm

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1800 200 700

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