Preventive cancer treatments may cause disease to "hibernate" and later relapse, study suggests

Preventive treatments designed to stop breast cancer from coming back actually cause cancer cells to mutate and “hibernate”, growing again years later, new findings suggest.

Researchers set out to explain why breasts cancer Recurrence can occur years after initial treatment Hormone therapy used to prevent breast cancer from coming back can trigger changes in certain cells, a study has found.

These changes cause cells to lie dormant rather than die, and the cells “wake up” years later, leading to relapses that are more difficult to treat.

But research has found that there may be a way to target these “sleeping” breast cancer cells before they wake up, giving new hope to patients with estrogen receptor-positive (ER+) breast cancer – a type of breast cancer that accounts for 10% of the population. 80% of all breast cancers.

Luca Magnani, professor of epigenetic plasticity at the Institute of Cancer Research in London, said: “After surgery to remove primary estrogen receptor-positive breast cancer, patients will receive hormone therapy for five to 10 years. Designed to kill any remaining cancer cells.

“We know this doesn’t work for all patients, as their breast cancer may come back years or even decades later.

“We want to better understand why breast cancer comes back so we can hopefully find ways to stop it – so people don’t have to live in fear or face the devastating news of recurrence.

“Our study uncovers a key mechanism by which cancer cells evade treatment by remaining dormant, hibernating before ‘waking up’ and starting to divide rapidly again years later.”

The study, published in the journal Cancer Discovery, found that inhibiting an enzyme called G9a prevents cancer cells from entering a dormant state and kills cells that have already hibernated.

Read more from Sky News:
What is preventive chemotherapy?
Kate and William ‘touched’ by public’s ‘warmth’
Kim ‘frustrated’ by speed of cancer recovery

Dr Tayyaba Jiwani, scientific engagement manager at Cancer Research UK, which funded the study, said: “Survival rates from breast cancer have doubled in the UK over the past 50 years due to improvements in detection and screening, but more than 11,000 people still die from it. Types of cancer by year.

“Although still in its early stages, the findings reveal potential new targets for developing innovative treatments to prevent breast cancer recurrence.”

Cancer Research UK says breast cancer is the second most common cause of cancer death among women in the UK, after lung cancer, with around 11,400 people dying from breast cancer every year (2017-2019).

Nearly 19,000 women across England will be diagnosed with the disease in 2022-23 as a result of the NHS screening programme.