Endocrine Abstracts

Case history: A 59 year old woman presented to hospital with severe abdominal pain, diarrhoea and vomiting. Her past medical history included end stage renal failure of unknown cause, renal transplant with antithymocyte globulin (ATG) induction ten years prior, treated pulmonary tuberculosis, hypertension and new onset diabetes after transplant (NODAT).

Investigations: A CT scan of the abdomen demonstrated an 85 x 74 x 96mm heterogenous mass arising from the right adrenal gland and infiltrating the liver. This was suspicious for adrenocortical carcinoma or phaeochromocytoma and she was referred to the endocrinology team. The patient had hypertension which was well controlled on a single oral agent, but she described paroxysmal episodes of anxiety associated with flushing and headache. There were no clinical features of cortisol or androgen excess. 24hour urine cortisol levels were normal (21nmol/day), and plasma and urine metanephrine levels were all within normal limits. The potential for an additional differential for her adrenal mass was considered on the basis of her history of immunosuppression and a very high serum level of Epstein Barr Virus (>200,000 copies): post-transplant lymphoproliferative disorder. An US-guided biopsy was undertaken to establish a histological diagnosis. She received alpha-blockade with doxasosin in preparation for this.

Results and treatment: Histology from the adrenal biopsy demonstrated an EBV positive high grade lymphoma, consistent with post transplant lymphoproliferative disease. No adrenal tissue was identified in the mass. Immunochemistry was positive for CD20 and CD79a. There was no evidence of metabolically active nodal disease or metastases above or below the diaphragm on FDG-PET CT. She was initiated on R-CHOP chemotherapy following oncology review.

Conclusions and points for discussion: This case demonstrates a rare cause of adrenal mass. Post transplant lymphoproliferative disorder is a common cause of malignancy in solid organ transplant patients, although a rare cause of isolated adrenal mass. Biopsy of adrenal masses is rarely undertaken due to the risk of seeding or causing hypertensive crises. However, this patient had a history of renal transplant, high cumulative immunosuppressive dosing and a high EBV titre. This in conjunction with normal metanephrines justified the biopsy in this case, and was imperative for confirming the diagnosis.