Pituitary metastasis from CLL – an extremely rare case

K Jeyaraman, Z Vakil, R Kaushal

Department of Endocrinology, West Middlesex Hospital.

We report an 84 year old lady with chronic lymphatic leukemia diagnosed in 2002. She is under the care of haematologists for stage A CLL that has always been stable. She presented to emergency department earlier this year with 3 days history of worsening frontal headache. She did not report visual disturbance or weakness. She was hemodynamically stable. Cranial nerve examination revealed right sided homonymous hemianopia with no other neurological deficit.

White cell count and lymphocytes were 53.9x10e9/L and 42.0x10e9/L respectively. CT head showed an abnormally enlarged pituitary gland measuring 1.7cm in diameter with features suggesting recent hemorrhage. MRI confirmed the above findings and revealed optic chiasmal compression on the left with edema on the right side of chiasm. CSF analysis showed elevated protein, normal glucose and no organisms were seen.  CSF cytology was not performed. Her anterior pituitary function tests including electrolytes were normal at that point.

The scans were reviewed by the neurosurgeons who decided to perform transphenoidal hypophysectomy. The pituitary gland and associated hematoma were evacuated successfully with no immediate post operative complications. Histology showed necrotic and haemorrhagic adenoma. Pathological features were consistent with apoplexy. Immunocytochemistry showed features diagnostic of leukemic infiltrate and consistent with chronic lymphocytic leukemia. It was thought in our case that the pituitary vessels were clogged by CLL cells which then left to the apoplexy. Post operatively she developed hypopituitarism with diabetes insipidus. She is currently on life long hormone replacement that includes hydrocortisone, thyroxine and desmopressin. She has residual right sided homonymous hemianopia. Haematologists are continuing to monitor her as usual.

Tumour metastasis to the pituitary gland is unusual and pituitary metastasis from CLL is extremely rare. Only 1% of the pituitary surgeries are performed to treat pituitary metastasis. Autopsy series have stated pituitary metastasis in approximately 5% of patients with malignant tumours. Only 7% of pituitary metastasis are reported to be symptomatic with Diabetes insipidus  being the most frequent presenting symptom in 50% of cases. Their rarity as well as the lack of specific clinical and radiological features impede their differentiation from other more common sellar lesions. The prognosis depends on the course of the primary neoplasm.