Menopause is one of many factors that can influence the risk of breast cancer in women. — Shutterstock
Breast cancer remains a pressing health concern for women across the globe, and there has been much discussion on how it may impact a woman entering the menopause phase in life.
In Malaysia, breast cancer holds the unfortunate distinction of being the leading cancer among women.
One in 19 Malaysian women face the risk of developing breast cancer at some point in their lives, resulting in approximately 3,500 lives lost annually.
Amidst these sobering figures, there is a critical need for comprehensive awareness and understanding of the risk factors that contribute to this disease.
Related to age
First and foremost, it is essential to understand that menopause itself does not inherently increase the risk of developing breast cancer.
Rather, the risk of breast cancer increases with age, and different seasons in a woman’s life bring about distinct hormonal changes.
Consultant clinical oncologist Dr Hafizah Zaharah Ahmad shares that these changes do play a significant role in breast cancer risk, primarily due to the influence of hormones like oestrogen and progesterone on the breast tissue.
High levels of oestrogen, especially over a prolonged period, can stimulate the growth of breast cells and increase the risk of mutations that may lead to cancer.
This is why factors such as early onset of menstruation, late onset of menopause and hormone replacement therapy (HRT) are associated with a higher risk, as they expose the breast tissue to oestrogen for longer durations.
In addition, obesity can also play a role in increasing the levels of female hormones in the body.
Dr Hafizah explains that fat in a woman’s body converts certain substances in the blood into oestrogen, increasing its concentration in the body.
In addition, she says: “Obesity disturbs the hormonal balance in the body.
“As we gain excess weight, more insulin – a hormone produced by an organ known as the pancreas – has to be secreted to prevent an excessive rise in sugar level.
“Apart from controlling the sugar level, insulin increases cell production and reduces cell death.
“That means there is more opportunity for something to go wrong in the body and for cancer to develop.”
Thus, eating well, staying active and maintaining a healthy weight decreases the risk for cancer development.
She adds: “Pregnancy and breastfeeding temporarily reduce a woman’s exposure to oestrogen and may have a protective effect against breast cancer.
“However, the risk may increase slightly after giving birth if the first full-term pregnancy occurs later in life.”
Consultant breast, endocrine and general surgeon Dr Suziah Mokhtar notes that this risk can be categorised into two types:
- Pre-menopausal, which is associated with a higher risk for hormone receptor-positive (HR+) breast cancer, and
- Post-menopausal, where there is an increased risk for hormone receptor-negative (HR-) breast cancer.
“Breast cancer tends to be more aggressive in younger, pre-menopausal women than in older, post-menopausal women,” she says.
“Menopause matters in terms of the specific treatments that might work for a patient.
“Pre-menopausal HR+ women may benefit from medicines that block the action of oestrogen.
“Fortunately for post-menopausal HR+ women, alternative medicines that lower oestrogen levels may also be used.
“When pre-menopausal HR+ women are considered to benefit from oestrogen-lowering medicine, chemical menopause can be achieved by using a drug that acts on the brain to suppress ovulation and the production of ovarian hormones.”
Still a danger
Due to the decrease of oestrogen associated with menopause, some may be of the impression that it acts as a shield against breast cancer, or that mammograms are no longer necessary for menopausal women.
“Breast cancer risk does increase with age, and the risk is higher for women who have not experienced menopause, but it does not mean that menopausal women are completely immune – in fact, breast cancer can and does occur during and after menopause.
“Another dangerous misconception about mammograms no longer being necessary is far from the truth.
“Regular mammograms remain a crucial part of breast cancer screening for menopausal women, and early detection through mammograms can be life-saving,” Dr Hafizah says.
Another misconception that causes many women to panic when they discover a breast lump is the assumption that it must be cancer.
However, not all breast lumps are malignant (cancerous).
In fact, the majority of breast lumps found during menopause are benign (non-cancerous).
Nevertheless, any new lump should be evaluated by a healthcare provider to rule out cancer.
Dr Suziah recounts the experience of a patient in her early 70s who was diagnosed with early breast cancer after her children brought her for a screening mammogram and ultrasound.
“Through staging investigations, we were able to confirm that the cancer was only localised in her breast.
"She was sent for a cardiorespiratory (heart and lung) assessment and subsequently counselled for surgery.
“As her cancer was small, her surgery was uncomplicated and she recovered well.
“Laboratory testing showed that her cancer was HR+, hence she was started on hormone therapy.
“Now, after a few years, she is still free of cancer and living her life to the fullest among her loved ones,” she shares.
Detection and prevention
Dr Suziah notes that regardless of menopausal status, early diagnosis methods for breast cancer do not differ.
Mammograms and breast ultrasounds are pivotal for early detection, often identifying cancer years before it becomes palpable (i.e. detectable by touch).
And a definitive diagnosis requires a tissue biopsy.
Treatment for breast cancer typically involves a combination of surgery, chemotherapy, radiotherapy, hormone therapy and targeted therapy, tailored to the specific characteristics of the cancer.
Says Dr Hafizah: “It’s essential to remember that while hormonal factors are significant, breast cancer risk is multifactorial.
“Genetics, family history and other environmental factors also play roles in determining an individual’s risk.
“Regular breast cancer screening and consulting with healthcare professionals can help assess and manage this risk effectively.”
Adopting a healthy diet that is high in fibre and low in fat, may indirectly lower a woman’s risk of getting breast cancer through the lower incidence of obesity.
Women who had early stage breast cancer are also less likely to suffer a relapse of the cancer if they adopt a healthy lifestyle with such a diet.
Together with adequate exercise and avoiding excessive weight gain, women of any age can reduce their risk of getting breast cancer.
