Test Catalog

Test ID: PFIB    
Parafibromin, Immunostain, Technical Component Only

Useful For Suggests clinical disorders or settings where the test may be helpful


Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Parafibromin is a protein encoded by the HRPT2 oncosuppressor gene, and the expression is reported to be decreased or absent in parathyroid carcinomas. Parafibromin is expressed in the nucleus of benign parathyroids, parathyroid adenomas, and other normal tissues, but shows loss of expression in parathyroid carcinomas, making it a good diagnostic tool to identify parathyroid carcinomas and distinguish them from parathyroid adenomas.

Interpretation Provides information to assist in interpretation of the test results

The positive and negative controls are verified as showing appropriate immunoreactivity. If a control tissue is not included on the slide, a scanned image of the relevant quality control tissue is available upon request. Contact 855-516-8404.


Interpretation of this test should be performed in the context of the patient's clinical history and other diagnostic tests by a qualified pathologist.

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

No significant cautionary statements

Clinical Reference Recommendations for in-depth reading of a clinical nature

1. Gill A, Clarkson A, Gimm O, et al: Loss of nuclear rxpression of parafibromin distinguishes parathyroid carcinomas and hyperparathyroidism-jaw tumor (HPT-JT) syndrome-related adenomas from sporadic parathyroid adenomas and hyperplasias. Am J Surg Pathol 2006 Sept:30(9):1140-1149

2. Juhlin C, Hoog A: Parafibromin as a diagnostic instrument for parathyroid carcinoma-lone ranger or part of the posse? Int J Endocrinol 2010

3. Kim HK, Oh YL, Kim SH, et al: Parafibromin immunohistochemical staining to differentiate parathyroid carcinoma from parathyroid adenoma. Head and Neck 2012 Feb;34(2):201-206. doi 10.1002/hed.21716