Endocrine Abstracts

Case: An 81-year-old man with type 2 diabetes, cerebrovascular disease and hypertension presented with a sudden onset of headache. CT scan and MRI scan of the head did not show any significant abnormality. Headache improved spontaneously and he was discharged with no cause for his headache being identified. Four months later he was diagnosed to have pan-anterior hypopituitarism at another hospital and was commenced on appropriate replacement therapy. Serum prolactin was not elevated. A repeat MRI scan done did not show any pituitary abnormality. Two months later he again presented to us with worsening headache, nausea and diplopia with a partial third nerve palsy. A repeat unenhanced MRI scan showed a pituitary lesion which was 20 mm×19 mm×13 mm in size abutting the optic chiasm with evidence of lateral extension to the left where the soft tissue surrounded the left internal carotid artery. The radiological appearance was not suggestive of metastatic deposits. In view of rapid development of this lesion he went on to have a biopsy of the lesion. Histological examination confirmed the diagnosis of a primary high grade B cell lymphoma. He was deemed unfit for chemotherapy in view of his co-morbidities and he is awaiting palliative radiotherapy.

Discussion: Primary pituitary lymphoma is rare with only a few case reports in the literature. It is predominantly observed in males around the 6th decade of age. Usual presenting features are headache, cranial nerve abnormalities and about half of cases have anterior hypopituitarism at diagnosis. Chemotherapy should be considered as the first line of therapy. Neurosurgical decompression of the mass does provide symptom benefit. Our case was unusual as hypopituitarism preceded the diagnosis at least by a few months.

Conclusion: Primary pituitary lymphoma should be considered as a possible diagnosis in patients presenting with rapidly progressing pituitary lesion.