Narod SA. Tamoxifen ChemopreventionâEnd of the Road?. JAMA Oncol. 2015;1(8):1033â1034. doi:10.1001/jamaoncol.2015.2247. Download citation file:
About Rare Diseases. A rare disease is defined by the European Union as one that affects less than 5 in 10,000 of the general population. There are between 6,000 and 8,000 known rare diseases. Around five new rare diseases are described in medical literature each week.
Medical Definition of Fibrodysplasia ossificans progressiva (FOP) Fibrodysplasia ossificans progressiva (FOP): A rare but dramatic genetic disorder that turns muscles, tendons and ligaments into bone, threatening to transform the victim into a statue of stone..