Pediatric Parathyroid Carcinoma: A Case Report and Review of the Literature

Abstract

Primary hyperparathyroidism (PHPT) is a rare endocrine disease in the pediatric population. Sporadic parathyroid adenomas remain the most common cause of pediatric PHPT. Parathyroid carcinoma (PC) is an extremely rare cause of pediatric PHPT. We report a 16-year-old boy presenting with a nonhealing fragility fracture of the right leg along with florid features of rickets. Examination revealed a neck mass, mimicking a goiter. Biochemical findings were consistent with PHPT. Imaging was suggestive of a right inferior parathyroid mass infiltrating the right lobe of thyroid. The patient underwent en bloc surgical excision of the parathyroid mass along with the right lobe of thyroid. Histopathology was suggestive of a PC. He achieved biochemical remission with normalization of serum calcium and parathyroid hormone levels. At follow-up, there was no biochemical or imaging evidence of recurrence or metastasis. Genetic analysis revealed heterozygous germline deletion of CDC73. An extensive literature search on PC was conducted, with an emphasis on the pediatric population. Thirteen cases of pediatric PC were identified. The median age of presentation was 13 years; there was no sex predilection. All cases were symptomatic; 31% had a visible neck mass. The median serum calcium and intact parathyroid hormone levels were 14.3 mg/dL and 2000 pg/mL, respectively. All patients underwent surgical excision, with 27% showing metastatic relapse. Our findings indicate that the preoperative features that could point toward a diagnosis of PC in a child with PHPT are a tumor size of >3 cm, thyroid infiltration on imaging, and severe hypercalcemia at presentation.

A Pediatric Parathyroid Carcinoma: An Unusual Clinical Presentation and Mini-review

“…Another form of PC is familial, which can occur in HPT-JT and FIHP. Besides, MEN1 and MEN 2A are rare causes of PC ( 6 , 23 ).…”

“…The range of serum calcium and iPTH was 12 - 20.7 mg/dL and 300 - 8638 pg/mL, respectively. IHC had been reported in two cases, which were both positive for parafibromin ( 6 ). Three cases had deletion mutation of CDC73, and another case was negative with regard to menin gene mutation.…”

“…Approximately 80% of pediatric PHPT cases result from PAs ( 5 ). Other causes include different genetic syndromes, namely multiple endocrine neoplasia 1 (MEN1), MEN 2A, hyperparathyroidism-jaw tumor syndrome (HPT-JT), and familial isolated hyperparathyroidism (FIHP) ( 6 ). PC is a rare cause of PHPT (< 1%), with only a few case reports describing this carcinoma in pediatric PHPT cases ( 5 - 8 ).…”

Primary Hyperparathyroidism Presenting as Posterior Reversible Encephalopathy Syndrome: A Report of Two Cases

“…Hence, a clinical diagnosis of PHPT was made; hypertension and PRES were attributed to the hypercalcemic crisis. In view of severe hypercalcemia, iPTH level more than 10 times upper limit of normal, young age, male gender, concomitant bone, and renal involvement, a possibility of parathyroid carcinoma was considered ( 16 , 17 , 18 ). Lack of similar family history, normal serum prolactin, and age/pubertal status matched serum IGF-1 levels, normal sella (on CEMRI), absence of any thyroid nodule and non-visualization of any jaw lesion on imaging made syndromic causes of PHPT less likely.…”

Primary Hyperparathyroidism Presenting as Posterior Reversible Encephalopathy Syndrome: A Report of Two Cases

“…Hence, a clinical diagnosis of PHPT was kept; hypertension and PRES were attributed to hypercalcemic crisis. In view of severe hypercalcemia, iPTH level more than 10 times upper limit of normal, young age, male gender, concomitant bone and renal involvement, a possibility of parathyroid carcinoma was kept (16)(17)(18). Lack of similar family history, normal serum prolactin and age/pubertal status matched serum IGF-1 levels, normal sella (on CEMRI), absence of any thyroid nodule and non-visualization of any jaw lesion on imaging made syndromic causes of PHPT less likely.…”