An illustration of breast cancer
Nolvadex (tamoxifen) 20 mg tablets.
Breast cancer showing an inverted nipple, lump, and skin dimpling
Crystallographic structure of afimoxifene (carbon = white, oxygen = red, nitrogen = blue) complexed with ligand binding domain of estrogen receptor alpha (ERα) (cyan ribbon).
Early signs of possible breast cancer
Tumor in the breast visualized by Breast-Computertomography (Breast-CT)
All types of alcoholic beverages, including beer, wine, or liquor, cause breast cancer.
Ducts and lobules, the main locations of breast cancers
Overview of signal transduction pathways involved in programmed cell death. Mutations leading to loss of this ability can lead to cancer formation.
Histopathologic types of breast cancer, with relative incidences and prognoses
A mobile breast cancer screening unit in New Zealand
Chest after right breast mastectomy
Internal radiotherapy for breast cancer
Breasts after double mastectomy followed by nipple-sparing reconstruction with implants
An extreme example of an advanced recurrent breast cancer with an ulcerating axillary mass
Breast cancer surgery in 18th century
Radical mastectomy, Halsted's surgical papers
The pink ribbon is a symbol to show support for breast cancer awareness.
MRI showing breast cancer
Excised human breast tissue, showing an irregular, dense, white stellate area of cancer 2cm in diameter, within yellow fatty tissue
High-grade invasive ductal carcinoma, with minimal tubule formation, marked pleomorphism, and prominent mitoses, 40x field
Micrograph showing a lymph node invaded by ductal breast carcinoma, with an extension of the tumor beyond the lymph node
Neuropilin-2 expression in normal breast and breast carcinoma tissue
F-18 FDG PET/CT: A breast cancer metastasis to the right scapula
Needle breast biopsy
Elastography shows stiff cancer tissue on ultrasound imaging.
Ultrasound image shows irregularly shaped mass of breast cancer.
Infiltrating (invasive) breast carcinoma
Mammograms showing a normal breast (left) and a breast with cancer (right)
Stage T1 breast cancer
Stage T2 breast cancer
Stage T3 breast cancer
Metastatic or stage 4 breast cancer
Stage 1A breast cancer
Stage 1B breast cancer
Stage 2A breast cancer
Stage 2A breast cancer
Stage 2B breast cancer
Stage 2B breast cancer
Stage 2B breast cancer
Stage 3A breast cancer
Stage 3A breast cancer
Stage 3A breast cancer
Stage 3B breast cancer
Stage 3B breast cancer
Stage 4 breast cancer

Tamoxifen, sold under the brand name Nolvadex among others, is a selective estrogen receptor modulator used to prevent breast cancer in women and treat breast cancer in women and men.

- Tamoxifen

The medications tamoxifen or raloxifene may be used in an effort to prevent breast cancer in those who are at high risk of developing it.

- Breast cancer
An illustration of breast cancer

8 related topics

Alpha

The location and development of endometrial cancer.

Endometrial cancer

Cancer that arises from the endometrium .

Cancer that arises from the endometrium .

The location and development of endometrial cancer.
The autosomal dominant inheritance pattern seen in Lynch syndrome
Immunohistochemistry of endometrial endometrioid carcinoma with wild-type pattern of p53 expression, with variable proportion of tumor cell nuclei staining with variable intensity.
Vaginal ultrasonography with an endometrial fluid accumulation (darker area) in a postmenopausal uterus, a finding that is highly suspicious for endometrial cancer
Polypoidal endometrial carcinoma
Relative incidences of endometrial carcinomas by histopathology.
Endometrioid endometrial adenocarcinoma—very high magnification—H&E stain
A keyhole hysterectomy, one possible surgery to treat endometrial cancer
alt=A diagram of stage IA and IB endometrial cancer|Stage IA and IB endometrial cancer
alt=A diagram of stage II endometrial cancer|Stage II endometrial cancer
alt=A diagram of stage III endometrial cancer|Stage III endometrial cancer
alt=A diagram of stage IV endometrial cancer|Stage IV endometrial cancer

Risk factors for endometrial cancer include obesity, diabetes mellitus, breast cancer, use of tamoxifen, never having had a child, late menopause, high levels of estrogen, and increasing age.

A dimer of the ligand-binding region of ERβ (PDB rendering based on ).

Estrogen receptor

Estrogen receptors (ERs) are a group of proteins found inside cells.

Estrogen receptors (ERs) are a group of proteins found inside cells.

A dimer of the ligand-binding region of ERβ (PDB rendering based on ).
The domain structures of ERα and ERβ, including some of the known phosphorylation sites involved in ligand-independent regulation.
A dimer of the ligand-binding region of ERα (PDB rendering based on ).
Nolvadex (tamoxifen) 20 mg
Arimidex (anastrozole) 1 mg

The ERα is found in endometrium, breast cancer cells, ovarian stromal cells, and the hypothalamus. In males, ERα protein is found in the epithelium of the efferent ducts.

Selective estrogen receptor modulators (e.g., tamoxifen, clomifene, raloxifene)

A bottle of raloxifene.

Raloxifene

Medication used to prevent and treat osteoporosis in postmenopausal women and those on glucocorticoids.

Medication used to prevent and treat osteoporosis in postmenopausal women and those on glucocorticoids.

A bottle of raloxifene.

It is also used to reduce the risk of breast cancer in those at high risk.

In the Study of Tamoxifen and Raloxifene (STAR) trial, 60 mg/day raloxifene was 78% as effective as 20 mg/day tamoxifen in preventing non-invasive breast cancer.

Anastrozole, a non steroidal aromatase inhibitor and a widely used drug in the treatment of breast cancer.

Aromatase inhibitor

Anastrozole, a non steroidal aromatase inhibitor and a widely used drug in the treatment of breast cancer.
Often used as a cancer treatment in postmenopausal women, AIs work by blocking the conversion of androstenedione and testosterone into estrone and estradiol, respectively, which are both crucial to the growth of developing breast cancers (AIs are also effective at treating ovarian cancer, but less commonly so). In the diagram, the adrenal gland (1) releases androstenedione (3) while the ovaries (2) secrete testosterone (4). Both hormones travel to peripheral tissues or a breast cell (5), where they would be converted into estrone (8) or estradiol (9) if not for AIs (7), which prevent the enzyme CYP19A1 (also known as aromatase or estrogen synthase) (6) from catalyzing the reaction that turns androstenedione and testosterone into estrone and estradiol. In the diagram, Part A represents the successful conversion of androstenedione and testosterone into estrone and estradiol in the liver. Part B represents the blockage of this conversion by aromatase inhibitors both in peripheral tissues and in the breast tumor itself.
Arimidex (anastrozole) 1 mg tablets

Aromatase inhibitors (AIs) are a class of drugs used in the treatment of breast cancer in postmenopausal women and in men, and gynecomastia in men.

Although tamoxifen (a SERM) traditionally was the drug treatment of choice, but the ATAC trial showed that AI gives superior clinical results in postmenopausal women with localized estrogen receptor positive breast cancer.

Tamoxifen, a nonsteroidal triphenylethylene antiestrogen and a widely used drug in the treatment of breast cancer.

Selective estrogen receptor modulator

Selective estrogen receptor modulators (SERMs), also known as estrogen receptor agonist/antagonists (ERAAs), are a class of drugs that act on the estrogen receptor (ER).

Selective estrogen receptor modulators (SERMs), also known as estrogen receptor agonist/antagonists (ERAAs), are a class of drugs that act on the estrogen receptor (ER).

Tamoxifen, a nonsteroidal triphenylethylene antiestrogen and a widely used drug in the treatment of breast cancer.
Figure 2: Nolvadex (tamoxifen) 20-milligram tablets (UK)
Figure 3: The domain structures of ERα and ERβ, including some of the known phosphorylation sites involved in ligand-independent regulation.
Figure 4: Structural basis for the mechanism of estrogen receptor agonist and antagonist action. The structures shown here are of the ligand binding domain (LBD) of the estrogen receptor (green cartoon diagram) complexed with either the agonist diethylstilbestrol (top, ) or antagonist 4-hydroxytamoxifen (bottom, ). The ligands are depicted as space filling spheres (white = carbon, red = oxygen). When an agonist is bound to a nuclear receptor, the C-terminal alpha helix of the LBD (H12; light blue) is positioned such that a coactivator protein (red) can bind to the surface of the LBD. Shown here is just a small part of the coactivator protein, the so-called NR box containing the LXXLL amino acid sequence motif. Antagonists occupy the same ligand binding cavity of the nuclear receptor. However antagonist ligands in addition have a sidechain extension which sterically displaces H12 to occupy roughly the same position in space as coactivators bind. Hence coactivator binding to the LBD is blocked.
Figure 5: 4-hydroxytamoxifen (red) overlaid with 17β-estradiol (black)
Figure 6: Trans-form of clomifene with the triphenylethylene structure in red.
Figure 8: Chemical structure of toremifene
Figure 9: Raloxifene has a benzothiophene group (red) and is connected with a flexible carbonyl hinge to a phenyl 4-piperidinoethoxy side chain (green).
Figure 10: Chemical structure of nafoxidine with the dihydronapthalene group in red.
Figure 11: Chemical structure of lasofoxifene shows cis-oriented phenyls.
Figure 12: Bazedoxifene includes an indole system (red) which is connected to an amine through a benzyloxyethyl chain (green).
Figure 13: Chemical structure of ospemifene. Ethoxy side chain ends with a hydroxy group (red) instead of a dimethylamino group as with first-generation SERMs.
Figure 14: The ABCD steroid ring system in 17β-estradiol.
Figure 15: "A ring" (A) and "D ring" (D) marked in raloxifene.

Tamoxifen is a first-line hormonal treatment of ER-positive metastatic breast cancer.

Toxicological issues prevented long term use of clomifene and further drug development for other potential applications such as breast cancer treatment and prevention.

A coronal CT scan showing a malignant mesothelioma
Legend: → tumor ←, ✱ central pleural effusion, 1 & 3 lungs, 2 spine, 4 ribs, 5 aorta, 6 spleen, 7 & 8 kidneys, 9 liver

Cancer

Group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body.

Group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body.

A coronal CT scan showing a malignant mesothelioma
Legend: → tumor ←, ✱ central pleural effusion, 1 & 3 lungs, 2 spine, 4 ribs, 5 aorta, 6 spleen, 7 & 8 kidneys, 9 liver
Symptoms of cancer metastasis depend on the location of the tumor.
The GHS Hazard pictogram for carcinogenic substances
Share of cancer deaths attributed to tobacco in 2016.
The incidence of lung cancer is highly correlated with smoking.
Cancers are caused by a series of mutations. Each mutation alters the behavior of the cell somewhat.
The central role of DNA damage and epigenetic defects in DNA repair genes in carcinogenesis
Chest X-ray showing lung cancer in the left lung
Three measures of global cancer mortality from 1990 to 2017
Engraving with two views of a Dutch woman who had a tumor removed from her neck in 1689
University of Florida Cancer Hospital
CancerTreeMammal
An invasive ductal carcinoma of the breast (pale area at the center) surrounded by spikes of whitish scar tissue and yellow fatty tissue
An invasive colorectal carcinoma (top center) in a colectomy specimen
A squamous-cell carcinoma (the whitish tumor) near the bronchi in a lung specimen
A large invasive ductal carcinoma in a mastectomy specimen

The benefits of screening for breast cancer are controversial.

Daily use of tamoxifen or raloxifene reduce the risk of breast cancer in high-risk women.

Femara 2.5 mg oral tablet

Letrozole

Femara 2.5 mg oral tablet

Letrozole, sold under the brand name Femara ) among others, is an aromatase inhibitor which is used in the treatment of hormonally-responsive breast cancer after surgery.

Tamoxifen is also used to treat hormonally-responsive breast cancer, but it does so by interfering with the estrogen receptor.

Her2 and Her3 distribution on a breast cell, (3D Dual Colour Super Resolution Microscopy SPDMphymod / LIMON, marked with Alexa 488 and 568)

HER2/neu

Protein that in humans is encoded by the ERBB2 gene.

Protein that in humans is encoded by the ERBB2 gene.

Her2 and Her3 distribution on a breast cell, (3D Dual Colour Super Resolution Microscopy SPDMphymod / LIMON, marked with Alexa 488 and 568)
Her 2 staining on patient breast cancer tissue identified as stage 3
The staining is seen as a cell membrane with continuous brown color.

Amplification or over-expression of this oncogene has been shown to play an important role in the development and progression of certain aggressive types of breast cancer.

Normally, estradiol and tamoxifen acting through the estrogen receptor down-regulate the expression of HER2.