Figure 3b-6: Sparsely granulated somatotroph adenoma with neuronal metaplasia. Atypical large, neoplastic ganglion cells can be seen in rare sparsely granulated somatotroph adenomas (long arrows). These cells show true metaplasia, expressing GH (top right), neurofilament (bottom left) and cytokeratins (bottom right). Note that both types of intermediate filaments aggregate in fibrous bodies (notched short arrows).