ECTOMESENCHYMOMA OF THE MEDULLA-OBLONGATA IN A CALF

An ectomesenchymoma was found in a 62-day-old female calf, and examine d immunohistochemically. The neoplastic cells were characterized by po sitive immunostaining for neurofilaments, glial fibrillary acidic prot ein, alpha smooth muscle actin, myoglobin, and keratin. This tumour, w hich displayed neurocytic, astrocytic, and myoblastic differentiation map have arisen from pluripotential ectomesenchyme. Brain rumours show ing multidirectional phenotypic expression presumably occur mainly in fetuses or calves.