After surgery breast tissue was found ER+, What is the drug of choice
I. Bertram G Katzung. Basic and Clinical Pharmacology, 11th edition, page 716.
II. Goodman and Gilman. The Pharmacological Basis of Therapeutics, 11 th edition, page 1422.
Antiestrogen therapy of hormone-receptor positive breast cancer agents
Selective estrogen-Receptor modulators (SERMs) Selective estrogen-Receptor downregulators (SERDs) Aromatase inhibitors (AIs)
SERMS (Tamoxifen, toremifene, raloxifenE.
Compounds with tissue-selective actions (estrogen agonist on some tissues, antagonism on certain others.
Tamoxifen and toremifene
· Used for treatment of breast cancer
· Antagonist on breast but agonist on bone and endometrium; Increased risk of:
Deep vein thrombosis and pulmonary embolism Endometrial carcinoma
a. Estrogen agonist in bone - exerts anti resorptive effect.
b. Does not cause increased risk of endometrial carcinoma and is protective against breast cancer.
c. Do not alleviate the vasomotor symptoms associated with menopause. Metabolism by CYP insignificant
d. Reduces both total cholesterol and LDL.
a. Hot flashes and leg cramps
b. Increase in deep vein thrombosis and pulmonary embolism
a. Selective estrogen down regulator - SERD
b. Inhibits estrogen receptor dimerization and leads to receptor degradation
c. Efficacious in treating tamoxifen resistant breast cancers.