Endocrine Abstracts

A 73 year old man presented in 1995 with impotence and a bitemporal field loss. Endocrine testing revealed hyperprolactinaemia (2741 mU/L) and hypogonadotrophic hypogonadism. Pituitary imaging confirmed the presence of a macroadenoma with significant suprasellar extension. He underwent uncomplicated transsphenoidal surgery, which was successful in decompressing the optic chiasm. Histology revealed a pituitary adenoma that immunostained weakly for prolactin only. In 1998 routine MRI showed slight enlargement of the tumour remnant and he was referred for external beam radiotherapy. The tumour remnant remained unchanged in February 2000 but 4 months later he presented elsewhere with neck pain and weakness of both upper and lower limbs. He was unable to walk due to weakness and for 1 week prior to his presentation he complained of constipation and urinary incontinence. Objectively he had a global weakness graded 2/5, with neurological signs compatible with an upper motor neurone lesion. C-spine MRI revealed an intradural extramedullary mass. He underwent extensive cervical laminectomy to completely excise a soft, friable, purple tumour that was adjacent to but distinct from the cord. He made a full neurological recovery. Histopathological examination revealed a malignant tumour with scattered mitoses and positive immunostaining for neuroendocrine markers. The tumour also stained for prolactin, in a similar pattern to that observed in the previously excised pituitary adenoma. He was subjected to external beam radiotherapy to the C-spine. In July 2001 he presented with rapidly failing vision. MRI showed significant regrowth of the pituitary macroadenoma, which again exhibited suprasellar extension. He underwent further transsphenoidal debulking and the tumour again showed a similar immunostaining pattern with little evidence of mitotic activity. In light of the weak staining for prolactin, he has been commenced on dopamine agonist therapy and continues to be followed. Pituitary carcinomas are very rare and frequently metastasise within the cerebrospinal axis.