Parathyroid tumors and related disorders

Abstract

Primary hyperparathyroidism (P-HPT) is a common endocrine disorder that occurs as a result of adenomas (80-85%), hyperplasias (10-15%) or carcinomas (o1%) of the parathyroid glands. Molecular genetic analyses of heritable P-HPT syndromes have provided considerable insight into the understanding of sporadic parathyroid tumors and hyperplasias. This review will focus on the criteria for classification of parathyroid proliferative disorders and will highlight our understanding of these lesions at the molecular level. Advances in radiological imaging techniques together with the rapid intraoperative parathyroid hormone assay will be reviewed with respect to current treatment approaches for P-HPT.

Soft Tissue Metastasis of Parathyroid Carcinoma: Description of a Difficult Case

“…Given the multitude of abnormalities described this finding is not totally unexpected. There was the distinct possibility of a HRPT2 mutation since the clinical syndrome more commonly includes parathyroid carcinoma and is associated with renal abnormalities -renal hamartomas, renal cell carcinoma, Wilms tumor and cystic kidney disease [2,3,6,11,12]. MENIN and RET mutations seem to be particularly associated with parathyroid hyperplasia and adenoma formation, although parathyroid carcinoma may occasionally occur.…”

“…The APC protein probably acts through the oncoprotein β-catenin [16]. These data have generally been interpreted according to the "two-hit" Knudson's hypothesis of oncogenesis [1][2][3].…”

“…However an indolent course is common, local growth being generally slow and regional lymphatic (30%) or blood-borne long distance metastasis, mostly in the lung (40%) or liver (10%) being less common and later events [1,2]. The pathological distinction between benign and malignant tumors may be difficult: only local invasion and/or distant metastasis unequivocally establish malignancy [1][2][3]. Surgical treatment is the only potential curative therapy.…”

“…Radiotherapy and chemotherapy are uniformly ineffective, even if new calcimimetic agents may offer some help in controlling hypercalcemia [1][2][3][4]. Parathyroid carcinoma has been described in relation to multiple endocrine neoplasia (MEN) type 1 MENIN mutation (locus 11q13), type 2 RET mutations (locus 10q11.2), the hyperparathyroidism-jaw tumor (HPT-JT) syndrome and familial isolated primary hyperparathyroidism HRPT2 mutations (locus 1q21-q31) [1][2][3][4]. All of them are autosomal dominant disorders, with constitutional mutations [1,2].…”

Parathyroid carcinoma

“…Most parathyroid carcinomas also exhibit aberrant immunohistochemical staining for parafibromin, the protein product of CDC73; complete loss of parafibromin expression is the most common staining pattern. As the large majority of benign parathyroid tumors (except in the setting of germline CDC73 mutation) display normal parafibromin staining, parafibromin immunohistochemistry may be considered as a diagnostic adjunct for parathyroid cancer in otherwise equivocal cases [22][23][24] but aberrant parafibromin staining alone is insufficient as a diagnostic marker of parathyroid carcinoma [25] .…”