Clinical course and endocrinological characteristics of pediatric pheochromocytoma

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: MON 596-630-Pediatric Endocrinology
Clinical
Monday, June 17, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board MON-623
Yoo-Mi Kim*, Ja-Hye Kim, Jin-Ho Choi, Beom Hee Lee and Han-Wook Yoo
Asan Medical Center Children's Hospital, Seoul, South Korea
Aim: Pheochromocytoma is a rare tumor that accounts for 1.7% in children diagnosed with hypertension. It is more prevalent in adults with an estimated incidence of 1/100,000, however, 10 to 20% of tumors were manifested during children and adolescents. The most common clinical manifestations are hypertension, diaphoresis and palpitation. This study investigated clinical and endocrine characteristics, and treatment outcome of pheochromocytoma in children and adolescents.

Methods: Five male patients with pheochromocytoma diagnosed before 15 years of age were included. The diagnosis and relapse of pheochromocytoma were confirmed by abdominal computed tomography (CT) and quantitation of both serum and urine cathecholamine and its metabolites. The clinical course, endocrinological characteristics, and radiologic findings were reviewed retrospectively.

Results: The mean age at diagnosis was 9.4 years (range, 1-14 years). All patients showed hypertension higher than 97th percentile for age- and sex-matched references. A one-year-old infant showed failure to thrive. One boy presented with visual disturbance due to occipital hemorrhage and two patients had hypertensive retinopathy. Echocardiography revealed left ventricular hypertrophy in three patients. The mean level of urine VMA, methanephrine and norepinephrine at diagnosis were 29.54 mg/day (0.7-6.9), 3.44 mg/day (0-0.8) and 1382.4 μgm/day (15-80). Only one patient had elevating urine epinephrine 2224 μgm/day (0-20). Adrenal CT demonstrated left adrenal mass in 5 patients. Hypertension was successfully controlled with labetalol in three patients, phenoxybenzamine in two patients, and prazocin and propranolol in one patient. The mean duration of medical treatment before surgery was 3.2 weeks (2-4 weeks). There were no surgical complications. After adrenalectomy, serum catecholamine and its metabolites were normalized and initial symptoms disappeared. Weight increased from –1.678 SDS to -0.68 SDS within 3 months after surgery. One patient had recurred pheochromocytoma twelve years after operation. As his father had pancreatic tumor, the patient investigated for VHL gene and was heterozygous for p.Arg167Gln.

Conclusion: Children and adolescents with pheochromocytoma exhibits wide spectrum of clinical presentations. In contrast to adult pheochromocytoma, biochemical finding showed a nor-adrenergic dominant pattern. Poor weight gain, sweating and noradrenergic dominant biochemical findings are typical findings in pediatric pheochromocytoma. The patients who have bilateral adrenal mass or family history needed genetic surveillance. Pediatric patients with hypertension should be screened for pheochromocytoma and long-term follow-up is needed in larger cohort of patients with pheochromocytoma in order to delineate clinical course and prognosis.

Nothing to Disclose: YMK, JHK, JHC, BHL, HWY

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