Sweaty and flustered, my breast cancer patient was experiencing hot flushes. The lack of good treatment is frustrating

The Guardian

17-06-2025

'Doctor, stop!' she abruptly commands me. 'I can't process a thing.'
I halt mid-sentence, and in the pause that follows, watch the evolution of a hot flush (also called a hot flash) in real time.
First her face flushes pink, then her neck and the part of her chest visible over the tank top she is wearing on a blistering winter morning. Beads of sweat form over her forehead. Her burning ears might warm my still-cold fingers. But most notable is her expression, changing from composed to flustered in a split second. She is like a defeated firefighter, battling to bring the conflagration under control before resorting to simply biding her time.
'Sorry about that,' she grimaces.
Going by the clock at the bottom of my screen, the 'event' takes two minutes from start to finish. In that time I have had a front seat to a dramatic version of the adverse effect that oncologists often mention in passing to breast cancer patients using anti-oestrogen therapy.
'How often do you experience this?'
'A dozen times on a good day,' she shrugs.
Roughly three-quarters of breast cancers are oestrogen-receptor positive, which means the cancer cells are stimulated by oestrogen. Women with this type of cancer benefit from oestrogen suppression, achieved via different methods including a pill, an injection and removal of the ovaries. This induces menopause in younger women and more complete oestrogen suppression in the already menopausal.
With more than 20,000 Australian women and 2 million women worldwide diagnosed with breast cancer every year, anti-oestrogen medication is akin to the penicillin of oncology. Each week, I write, renew and replace multiple scripts.
But while every prescriber mentions the anticipated side-effect of hot flushes, it strikes me that no one (including me) quite explains the living horror that many patients go on to experience.
Why is that?
Women who have concluded an arduous trek of chemotherapy and radiation for early breast cancer express the hope of 'never having to go through this again'.
Women with metastatic breast cancer harbour the hope that their cancer, while not curable, may remain at bay for years.
Every woman's risk profile warrants a tailored conversation but, broadly speaking, imagine giving this advice: 'There is an effective medication to reduce recurrence risk and improve survival. Over the many years you will be on it, you could experience hot flushes, stiff joints, disturbed sleep, low mood, weight gain and sexual dysfunction.'
If it sounds like punishment served at the end of a punishing diagnosis, it is. However, when a drug works, oncologists want to encourage adherence and hope that the side-effects either don't occur or can be managed.
'Vasomotor symptoms', the medical term for hot flushes, affect up to 90% of women with breast cancer and are often severe. Up to half of all women prescribed anti-oestrogen medication stop taking the drug – and they are just the ones who tell us. Every oncologist knows the heart-sink moment when a high-risk patient declines treatment. But we also know all too well the toll that led them to do so.
Given the ubiquitous nature of hot flushes, the lack of good treatments is frustrating. Of the panoply of advertised options such as cognitive behavioural therapy, acupuncture, hypnosis, diet, exercise and off-label use of antidepressants and anticonvulsants, none has been shown to help in a meaningful way.
Then there is the irony of taking one medication to counter the side-effect of another and gaining weight and its associated complications in the process.
As a result, most women just put up with the trailing cost of having breast cancer.
Now, there is hope. In a randomised controlled trial of drug versus placebo, a once-daily pill meaningfully reduced hot flushes in women taking anti-oestrogen therapy for breast cancer. Elinzanetant works by affecting the brain signals involved in temperature regulation.
At baseline, women experienced a mean of a dozen daily episodes. By one month, 61% of women on active treatment reported a reduction of at least 50% in the daily frequency of moderate-to-severe hot flushes compared with 27% on placebo. Sleep quality improved, as did overall quality of life. Crossover from placebo to the active drug resulted in similar findings.
No drug is without side-effects. More than 60% of women in each group reported at least one mild adverse event but severe ones were rare. Somnolence, fatigue and diarrhoea were reported more frequently in the active therapy group but they can also be caused by cancer therapy. More than 90% of women who completed one year of treatment chose to continue for an optional two years, suggesting a high rate of acceptability.
The drug is yet unapproved and oncologists will seek more details before widespread prescribing.
Breast cancer outcomes are poorer in non-white women but 88% of the participants were white. Will this drug be effective in, and tolerable for, all eligible patients.
Does taking the 'remedy' drug improve adherence to the primary one that reduces cancer risk? This would be the point of prescribing it.
Finally, patients on clinical trials are strictly selected and heavily monitored. Will the real-world experience match the clinical trial experience? We know that it rarely does.
On the way out, I commend my patient's determination to persevere with difficult treatment, and she smiles gratefully at the acknowledgement.
She is only two years into treatment. I allow myself to envision a day when there will be room for reprieve.
Ranjana Srivastava is an Australian oncologist, award-winning author and Fulbright scholar. Her latest book is called A Better Death