Neuroendocrine differentiation in male breast carcinomas
The presence of neuroendocrine differentiation, as expressed by cellular chromogranin immunoreactivity, was investigated in paraffin‐embedded tissue material from 51 consecutive cases of male breast carcinoma. From six of these cases electron microscopic studies were included. Chromogranin‐immunoreactive cells were present in solid cords and delineated tubular structures. Ultrastructurally, dense