Endocrine Abstracts

Background: PTHrP related hypercalcemia is a common cause of humoral hypercalcemia of malignancy associated with carcinoma of the lung, prostate, and breast and uncommonly in haematological malignancies and malignant pheochromocytoma.

We present a case with an unusual finding of micrometastases within a benign paraganglioma and PTHrP release from micrometsatses.: Case presentation

72 years old lady presented with tiredness, poor appetite, generalized body aches, and constipation. She had a past history of hypertension, hypercholesterolemia, and carcinoma of left breast treated 5 years ago, no recurrence and was discharged a month before her current presentation. Staging CT scan at diagnosis of breast cancer showed a left adrenal mass 3.8×3.3 cm which remained unchanged on follow-up images. 24 h urine catecholamines at that time were normal.

Investigations: FBC, U&E, CXR normal. Corr Ca. 3.91 mmol/l, PO4 0.79 mmol/l, ESR108 mm/h, and PTH 0.3 pmol/l. Protein electrophoresis, TSH, prolactin, ACE, and vitamin D normal. CT scan showed left mastectomy and left adrenal mass which remained unchanged. Bone scan showed no metastases, USS parathyroid glands normal, urinary metadrenaline 5895 nmol/24 h, normetadrenaline 3997 nmol/24 h, and 3-methoxytyramine 1086 nmol/24 h. PET scan showed left adrenal mass. MIBG scan showed increased activity in left adrenal gland. PTHrP elevated 31.9 pmol/l. Patient treated for pheochromocytoma but hypercalcemic again few days after adrenalectomy. Histology showed paraganglioma with micrometastases from previously treated breast cancer. Micrometastases also confirmed on bone marrow biopsy.

Discussion: Adrenal incidentaloma on staging CT scan diagnosed as adenoma was a paraganglioma. The delay in diagnosis of paraganglioma caused complications and the presence of paraganglioma mislead the team as the likely cause of hypercalcemia which caused further delay in diagnosis of micrometastatses.

Conclusion: Not all adrenal incidentalomas are adenomas. The proportion of pheochromocytoma among incidentalomas has been reported upto 11%. As many of these individuals have no typical clinical symptoms, a careful biochemical evaluation is necessary by the endocrinologists to avoid a delay in diagnosis and complications.