Introduction:
Double-Hit lymphoma (DHL) is a type of high-grade B cell lymphomas with rearrangements of MYC with BCL2 or BCL6 genes. DHL are more aggressive and carry and worst prognosis compared to other Non-Hodgkin lymphomas. Although CNS involvement at diagnosis is frequent and estimated at 10%, isolated involvement of the hypothalamus-pituitary axis is very rare and estimated at a frequency of <0.5% among systemic lymphomas.
Case description:
This case describes a 46 year old female presenting acutely with pituitary failure characterized by headache, fatigue and dizziness. Laboratory test showed severe hyponatremia at 128 mmol/L and acute kidney injury. Emergency CT scan of the head showed abnormal thickening and enhancement of the pituitary infundibulum later confirmed on MRI, with the impression of lymphocytic hypophysitis with a broad differential aetiology. She was prompted started on appropriate hormonal replacement with significant clinical improvement.
Multiple indurate lesions skin over face, shoulders and lower abdomen were ntoed, and preliminary histology suggested likelihood of B cell non-Hodgkins lymphoma. Fluorescence in situ hybridisation (FISH) later confirmed rearrangements for MYC and BCL2 genes. Staging CT revealed cardiac and retroperitoneal involvement with obstructive hydronephrosis requiring stenting.
Patient was promptly started on short intensive chemotherapy in view of then performing autologous stem cell transplant. PET scan prior to stem cell transplant confirmed complete remission and patient is regularly monitored while recovering.
Discussion:
Acute panhypopituitarism can be caused by a broad spectrum of aetiologies. Most of them are usually slow to progress, commonly managed in the outpatient settings and often untreatable. This case illustrates an aggressive type of Non-Hodkin lymphoma diagnosed after presenting with pituitary infiltration that responded completely to prompt aggressive chemotherapy.