Gastrointestinal stromal tumor historical perspective

History
Until the 1990s, all non-epithelial tumors of the gastrointestinal tract were called "gastrointestinal stromal tumors" from smooth muscle origin. Histopathologists generally did not distinguish between the types, as this did affect neither therapy nor prognosis. Subsequently, CD34, and later CD117 were identified as markers that could distinguish the various types.