COVID-19 vaccines and mammography

covid vaccines and mammograms occupational health news

COVID-19 vaccination and mammograms

The impact of COVID-19 vaccines on mammograms has started appearing in news articles in recent weeks. Concerns have been raised that “false positive” results may be triggered by the vaccines, leading to anxiety and possibly unnecessary treatment amongst patients.It has been suggested that the vaccines may cause swelling in glands under the arm (in axillary lymph nodes) which may be mistaken as breast cancer. If something is mistakenly reported on the image taken during a mammogram, it may lead to an unnecessary biopsy. That would risk unnecessary discomfort, distress and expense.

Swelling in Lymph nodes

Lymph node enlargement is seen in malignancies such as breast cancer, lung cancer and lymphomas. However, it can also be caused by a response to infection, as well as recent vaccination. If it occurs following vaccination, it is usually in the corresponding arm.Swelling in Lymph nodes is also not unusual following vaccinations that trigger a strong immune response, such as the COVID-19 vaccine.

Academic papers covering the topic so far are based on very limited information. There have been very few cases of lymph node enlargement following COVID-19 vaccination. The study referred to most news articles so far was based on a cohort of four patients.

Lymph node swelling has been reported in some COVID-19 vaccine trials. However, it is a rare occurrence. The gold standard study tracking 43,548 people who received the Pfizer-BioNTech vaccine showed that lymph node swelling was reported in <0.1% of participants.

What if swelling is noticed?

Anyone who finds swelling or notices anything unusual about their breasts should talk to a medical professional. A referral for imaging via mammography and occasionally via ultrasound is usually made.

Regular screening via mammography can find problems before they are noticed physically. This is why they are used in population screening in the NHS. Mammograms are also routinely included in corporate health screening programmes.

Anyone who experiences lymph node swelling following COVID-19 vaccination should see their GP to be examined to rule out possible malignancy. Most will be followed-up in the short term, to check if it has resolved, before referring onward for imaging and potentially unnecessary biopsies.

When should I have the mammogram?

Guidance has just been published in the BMJ suggesting patients opt for routine screening before receiving the COVID-19 vaccine, if possible.

Alternatively, deferring routine screening mammography to 4 to 6 weeks after the 2nd dose of vaccination, would enable imaging when most lymph nodes that have reacted will have usually resolved.

Mammography saves lives

In the UK, the NHS offers breast screening to women over the age of 50 and it is recommended every 3 years. This is a longstanding screening programme proven to reduce the morbidity and mortality from breast cancer.

It is important to discuss with your doctor if you are unsure about when you should have your screening mammogram, rather than cancelling it altogether.

If you (or anyone you know) has any concerns about lumps in your breasts, or under the arms, regardless of whether you have recently had a COVID vaccination, you must speak to your GP.

Your doctor can examine you and refer you for imaging and specialist assessment if needed. Always ask for help at the earliest opportunity.

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