A homogeneous hypoechoic mass of a submucosal origin can be observed with echoendoscopy. Histological studies show that these lesions are composed of spindle-shaped cells that intertwine with inflammatory infiltrate which has a striking abundance of eosinophils.
En estudio histológico está formada por células fusocelulares que se entremezclan con infiltrado inflamatorio, con una llamativa abundancia de eosinófilos; no suele encontrarse eosinofilia periférica.