Cancer 12: Cancer as a disease- Breast Cancer Flashcards
(91 cards)
Leading cause of cancer death in female
Breast cancer is the leading female cancer
1 in 5 cancer deaths in females
Most common cancer in UK
What is happening to incidence of breast cancer
Currently, around 55,000 women develop breast cancer every year in the UK.
Breast cancer incidence is rising.
T/f breast cancer is the leading cause of cancer deaths in females in UK
F… In the UK breast cancer is the second most common cause of death from cancer in women after lung cancer and accounts for 7% of all cancer deaths.
What is the reason for the fall in breast cancer deaths since 1980s
Early Diagnosis, Chemo/Radiotherapies
Hormonal Therapies.
Most common type of breast cancer
Carcinoma (tumour of epithelial cells)
What is special about the breast as a gland
If is the only gland that develops post-natally.
Rudimentary gland before puberty.
The main spurt of growth occurs at puberty and is dependent on high levels of estrogen, as well as progesterone produced by the ovary
Following puberty, when might the breast develop more
Post pubertal growth…. cyclical increase in ductal branches (extensive branching into fat pad)
Occurs due to lactation cycle
AND
pregnancy
Conversion of the breast into a secretory gland requires differentiation and, interestingly, this is a reversible process such that milk is not continued to be secreted long after pregnancy
What happens to the breast in pregnancy
What occurs following pregnancy
Pregnancy is characterised by large increases in side branching and development of secretory acini from the terminal ductal alveoli. Following weaning the mammary gland regresses to a near pre-pregnancy state through a process involving extensive apoptosis .
T/f all breast development is dependent on oestrogen
F
Estrogen does not seem to be necessary for the prenatal development of the mammary gland, but is required for prepubertal and pubertal gland development.
Outline the cellular organisation of the ducts secreting milk
Lumen lined by epithelial cells
Then layer of myoepithelial cells
They make contact with the basement membrane
Outline the main two types of BC
invasive ductal carcinoma (up to 80% of all BC) and invasive lobular carcinoma (5-15%)
How do the most common breast cancers develop
The general picture that emerges for the most common BC types, invasive ductal carcinoma (up to 80% of all BC) and invasive lobular carcinoma (5-15%) is that these cancers all originate in the terminal duct lobular unit and progress from an
initial hyperproliferative stage,
to a pre-cancerous, in situ carcinoma stage
and then to invasive BC.
What does in situ refer to in breast cancer
Within in the duct
Which cells in the breast have oestrogen receptors
luminal epithelial cells have receptors required to respond to steroid hormones (particularly oestrogen). NOT all of the luminal cells have these receptors (they are expressed and down-regulated constantly). Between 10-20% of these luminal cells can response to oestrogen
What is benign carcinoma in situ
locally proliferating cells that may appear as a lump. They are easily diagnosed as non-cancer. However, this is a precursor state for the development of cancer
local proliferation of cells that are LUMINAL. They proliferate within the tubule, WITHOUT breaking away from the tube. There is no loss of the myoepithelial cells.
What is lobular carcinoma
So there are tumour cells have a tubular like arrangement (i.e. dervided from the lobule), but the myoepithelium has been lost because the carcinoma has now spread out of the lobule and is invasive
What is medullary carcinoma
The tumour cells are packed full of neuroendrocrine vesicles
neuroendocrine
This is a type of invasive ductal carcinoma
Outline the structure of the breast
The ducts are embedded in a fatty stromal tissue
T/F there is a cancer type for every cell type ijn the breast
T… including the stromal tissue
But most common are the ducts and the lobular carcinoma, which are epithelial
T/f most breast cancers are in the luminal epithelial cells, not in the myoepithelial cells
True, but myoepithelial cells are important cells for laying down the tubular structure of the breast (morphogenic) , and there are cancers of these cells too which are hard to treat
State the types of tumour cells in breast cancer
They can be lobular, medullary, but most (80%) are infiltrating ductal carcinoma
The carcinoma has no consistent structure in most cases and cannot be separated into subgroups (NOS= not otherwised specified)
In the not-otherwised specificied breast cancers (i.e. not lobular or medullary), how can you classify them
So this is 80% of breast cancers.
They are either oestrogen receptor positive or negative
The oestrogen receptors can be stained with antibodies.
If there are oestrogen receptors, it means the tumour grows in response to oestrogen
T/f most breast cancers are oestrogen positive
T! From the staining, pathologists can look at the strength of the staining and grade how oestrogen responsive it is (+,++,+++) for growth
What percentage of cancers are oestrogen receptor positive
80% (tested using staining)