lUMINAL-A (eSTROGEN RELATED) BREAST CANCER
LUMINAL A – ESTROGEN RELATED BREAST CANCER
Estrogen is a female sex hormone produced by the ovaries, adrenal gland, placenta and fat. Too much Estrogen in the body can cause cells to divide, proliferate and mutate to cause breast cancer.
ESTROGEN TUMORS CAN BE UNDERSTOOD AS EITHER,
- A sub-type in and of itself, or
- A sub-sub type breaking it down into molecular categories (stuff to do with the genes).
I remember the oncologist telling me almost immediately that my breast cancer was Estrogen related though it meant little to me at the time. However, I had taken an HRT contraceptive pill when I was younger and then later when suffering from menopause. A flash of guilt passed through me though I was strongly advised not to blame myself and I’m passing that onto you whether you took those pills or not.
Anyway, it turns out that the speed of the dividing cells determines the seriousness of breast cancer. Estrogen-positive breast cancer is deemed to be less serious because the mutated cells do not split as fast as other types like, for example, Triple Negative Breast Cancer (TNBC).
On the other hand, Estrogen tumors from an East African perspective, might not be the same as that for white Europeans. In Ethiopia, Estrogen breast cancer is said to be quite aggressive but once again, we don’t have sufficient research nor data to be sure.
THERE ARE TWO TYPES OF ESTROGEN BREAST CANCER:
- Estrogen Positive (ER+) and
- Estrogen Negative (ER-)
In general, Estrogen-positive is not as serious as the other one because Estrogen-negative does not have a receptor and that is not a good thing for those diagnosed with ER-negative breast cancer.
WHAT IS A RECEPTOR?
Receptors sit on top of cancer cells like little light switches that can be flicked off or on. By way of these switches (read receptors), communication is made to the cancer cells telling them to multiply, or not. In the case of Estrogen positive (ER+), the light switch is turned ‘on’ so the mutated cells keep dividing and will do so unless the switch is turned ‘off’.
Luckily, there are drug treatments that can turn off the ER+ receptor. The drug doesn’t necessarily kill the cancer so much as blocks the mutated cell from growing. Unfortunately, ER- tumors do not respond to anti-Estrogen therapy so have poor outcomes.
Treatments can be personally targeted because of the presence of those receptors. This means the lack of a receptor makes it difficult to treat the tumor because the signals that identify cancer cell growth go unseen. The speed at which the cells mutate in breast cancers that don’t have receptors is also much faster and therefore is more dangerous. In effect, a fire starts from an unknown source, and nobody knows how to put it out properly. That’s what you’ve got with Estrogen-negative breast cancer.
HOW COMMON IS ESTROGEN RELATED BREAST CANCER?
Estrogen status is more distinguishable by race/ethnicity than any other type of breast cancer. ER+ is also the most common form of breast cancer among white European women – about 80 per cent. Even though a great deal has been said about TNBC as being more prevalent in black women (compared to all ethnic groups including white women), most black women with breast cancer in the UK and the US, have hormone-receptor-positive tumors.
I say hormone receptor positive instead of ER+ because this also includes the hormone progesterone (PR) which frequently mirrors Estrogen. When ER+ is present so too is PR+ often present. At the same time,
- ER+ is lower among Black women (compared to white women), by about 20 per cent.
- ER+ tumor incidences are higher in black women than any other non-white racial/ethnic group in the US and UK for reasons that remain unknown.
ER-NEGATIVE BREAST CANCER IS COMMON AMONG:
- African Americans by 31.7% and
- European Americans by 17.5%.
TO EMPHASIS THE AFRICAN HERITAGE ER+ POINT
- ER+ is the most common breast cancer for black and white women in the UK and the US
- ER+ is the most common breast cancer in urban Soweto SOUTH AFRICA
- ER+ is the most common breast cancer in EAST AFRICA
- ER+ is the most common breast cancer in ZAMBIA
- ER+ (aggressive) is the most common breast cancer in ETHIOPIA
- ER+ is the most common breast cancer in TOGO
- ER+ is the most common breast cancer (under 50 years) in NIGERIA
- ER+ is the most common breast cancer in JAMAICA
- ER+ is the most common breast cancer in HAITI
THE GENERAL GLOBAL PATTERN IS SIMILAR TO THE US
- White women have the highest ER+ tumors in the US and
- Black women have the highest ER – tumors in the US.
ALSO
- In a large African review, comparisons consistently reported a lower frequency of ER+ tumors in indigenous women in Africa relative to Western white women, or in black relative to white women in South Africa, consistent with documented ethnic differences in the US – (2014)
- In a Zambian study, the most common receptor types were Estrogen+ or Progesterone+ receptors at (57%), followed by TNBC with (31%) – (2020)
- In East Africa, the estimated 5-year survival from ER, PR (or HER2) receptor tumors is (37.7%) and far lower than the US average of (90%) – (2021)
- The estimated 5- year BC survival for receptor-defined breast cancer in East Africa is 37.7%, and compares with 35.2% for West Africa and 48.1% in South Africa – (2021)
- In the Sudan and Eritrea (54%) of women with BC had ER negative and 62% PR negative tumors – (2017)
OTHER POSSIBLE LINKS TO ER TUMORS INCLUDE:
- A large cohort study of AA women, suggested TYPE 2 DIABETES gave a 40% increased risk of developing ER- breast cancer. The association was observed primarily among women who were not obese. Type 2 diabetes was not associated with incidence of ER+ breast cancer.
- BREAST FEEDING – Some studies have argued that a lack of breast feeding has links to an increase in developing breast cancer.
- GENETIC VARIATIONS – Hormone-dependent breast cancers arising in black women are more resistant to treatment than tumors from their white peers. This in part maybe due to genetic variations between black and white women.
- AGE OF MENOPAUSE – A number of studies make clear distinctions between pre and post menopause. Susceptibility to BC invariably affects young women and those postmenopausal.
- AGE OF MENARCHE – During women’s reproductive years (broadly the time between menarche and menopause) the ovary produces steroid hormones affecting development and function of the breast. Early menarche and late menopause are known to increase women’s risk of developing breast cancer.
- HORMONAL REPLACEMENT THERAPY – HRT is associated with a small increase in the risk of breast cancer. The length of time on HRT increases the risk of breast cancer and falls after you stop taking it. If you’re taking HRT, it is extra important that you attend all breast screening appointments.
