Benign pheochromocytoma and PTH-rp depended hypercalcemia

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: MON 37-82-Pheochromocytoma & Paraganglioma
Clinical
Monday, June 17, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board MON-79
Daniel Alberto Cadena*1, Naga Nalini Tirumalasetty1, Susana Laura Dipp2 and Brandy Ann Panunti3
1Ochsner Clinic Foundation, New Orleans, LA, 2Ochsner Medical Foundation, New Orleans, LA, 3Ochsner Med Cntr, New Orleans, LA
Pheochromocytoma is a rare neuroendocrine tumor, occurring in <0.2% of patients with hypertension. Its association with hypercalcemia has been documented in MEN 2A syndrome with parathyroid disease, benign and malignant pheochromocytomas. We are reporting a case of benign pheochromocytoma with hypercalcemia secondary to parathyroid hormone related protein secretion.

A 47-year-old Caucasian male with history of uncontrolled hypertension presented with severe headache, flushing, palpitations, sweating and chest discomfort associated with diffuse abdominal pain, polyuria and polydipsia for 6 weeks. Family history was negative for endocrine malignancies. Vitals signs were temp 38.2 °C, BP: 146/77 mmHg. An abdominal CT showed a 8.0 x 8.4 cm heterogenic right adrenal mass. His plasma free normetanephrine 2686 pg/ml (<148 pg/ml), plasma total metanephrine 2757pg/ml (<205 pg/ml) and 24 hr urine normetanephrine 3713 umol/mol CRT (0-247 umol/mol CRT) confirmed the diagnosis of pheochromocytoma. Patient also had hypercalcemia with calcium 11.9 mg/dl (8.7-10.5 mg/dl), PTH-rp 7.0 pmo/L (< 2.0 pmol/L), calcitonin 8.9 pg/ml (0.0-7.5 pg/ml), undetectable PTH and 1,25 vitamin D of 68 pg/ml (15-75 pg/ml). The patient was prepared preoperatively with phenoxybenzamine and IV fluids. His hypercalcemia was normalized with hydration. He successfully underwent laparoscopic right adrenalectomy. After surgery plasma free metanephrine, plasma free normetanephrine, and plasma total metanephrine became normal. Calcium levels decreased to 7.2 mg/dl (8.7-10.5 mg/dl), PHT-rp decreased to 0.2 mg/dl (8.7-10.5 mg/dl) and PTH significantly increased to 80 pg/ml (10–65 pg/ml). The pathology reported a large mass of 10 centimeters compatible with pheochromocytoma. Immunohistochemical stains were positive for chromogranin, S100 and synaptophysin. PTH-rp staining was not performed.

Discussion: Benign pheochromocytoma with hypercalcemia secondary to PTH-rp is very unusual. This case summarizes the clinical and biochemical findings of a pheochromocytoma co-secreting both metanephrine and PTH-rp. Although PTHrp was not measured in the tumor, the post operative changes of calcium, PTH and PTHrp strongly suggested hypercalcemia secondary to the tumor production of PTHrp.

A case of pheochromocytoma producing parathyroid hormone-related protein and presenting with hypercalcemia.Kimura S, Nishimura Y, Yamaguchi K, Nagasaki K, Shimada K, Uchida H.J Clin Endocrinol Metab. 1990 Jun;70(6):1559-63.

Nothing to Disclose: DAC, NNT, SLD, BAP

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm

Sources of Research Support: Production and secretion of parathyroid hormone-related protein in pheochromocytoma: participation of an alpha-adrenergic mechanism.Mune T, Katakami H, Kato Y, Yasuda K, Matsukura S, Miura K.J Clin Endocrinol Metab. 1993 Mar;76(3):757-62.