Assertion: fibrosis's disease | /r/HasProperty | unknown or spontaneous origin
Facets:
value: in these cases
type: TEMPORAL
Source sentences:
text: The term myelofibrosis alone usually refers to primary myelofibrosis (PMF), also known as chronic idiopathic myelofibrosis (cIMF); the terms idiopathic and primary mean that in these cases the disease is of unknown or spontaneous origin.