Information AgeMedicine & Health Tamoxifen for breast cancer 1977Notable Tamoxifen, which blocks estrogen's effect on tumors, is approved for breast cancer, the first widely used targeted hormonal cancer therapy. ▲ MattersSaveShareTrace roots Longest chain: The Big Bang → First stars ignite → Supernovae seed heavy elements → The Sun forms → Earth forms → First oceans → First life → Photosynthesis evolves → Great Oxidation Event → Complex cells (eukaryotes) → Multicellular life → First animals → Cambrian Explosion → First vertebrates → Jawed fish → Fish walk onto land → The amniotic egg → The Great Dying → Dinosaurs appear → Asteroid ends the dinosaurs → Early primates → Apes split from monkeys → Human line splits from chimpanzees → Walking upright → First stone tools → Genus Homo appears → Homo erectus → Control of fire → Habitual fire and cooking → Homo sapiens appears → Complex language → Natufian villages → Oldest known bread → Agriculture begins → Irrigation → Uruk and the first cities → Cylinder seals → Writing (cuneiform) → Babylonian mathematics → Babylonian astronomical diaries → Thales and natural philosophy → Trial and death of Socrates → Plato's Academy → Aristotle's Lyceum → Alexander's conquests → Death of Alexander and the Hellenistic kingdoms → Seleucid Empire founded → Parthian Empire founded → Sasanian Empire → Birth of Muhammad → Muhammad's first revelations → The Hijra → Conquest of Mecca → Death of Muhammad and the Rashidun caliphate → Arab conquests → Abbasid Caliphate → Battle of Talas → Paper reaches the Islamic world → House of Wisdom → Ibn al-Haytham's Book of Optics → Bacon's Novum Organum → First controlled clinical trial → Vitamins → First chemotherapy remissions → Tamoxifen for breast cancer Community notesLoading notes… Learn more ranked by votesBookSiddhartha MukherjeeThe Emperor of All Maladies ↗Editor's pickVideoSearch on YouTubetamoxifen breast cancer history ↗Editor's pick