Hypercalcemia and local production of parathyroid hormone-related protein by a perisellar rhabdomyosarcoma after remote pituitary irradiation.

Abstract

OBJECTIVE:

To describe a case of metastatic rhabdomyosarcoma originating from the sphenoid sinus in a patient previously treated with conventional irradiation for a prolactinoma, presenting as hypercalcemia in the setting of a normal level of serum parathyroid hormone-related protein (PTHrP).

METHODS:

We report the case of a patient who underwent remote pituitary irradiation for a prolactinoma and then presented decades later with hypercalcemia of unknown cause. His clinical course, the initial biochemical and radiologic investigations, and the results of examination of pathology specimens are reviewed.

RESULTS:

The patient was found to have a mass in the sphenoid sinus. The pathologic features were consistent with alveolar rhabdomyosarcoma. Although he had a normal serum PTHrP level, staining of his tumor with an antibody against PTHrP revealed local production of PTHrP at the tumor margins. His bone marrow biopsy specimen showed 100% involvement with rhabdomyosarcoma.

CONCLUSION:

PTHrP staining of pathology specimens might explain hypercalcemia of undetermined cause in patients with a known malignant lesion, in whom elevated serum PTHrP levels cannot be demonstrated.

• Authors: Jose C Florez, Doug W Burton, Paula M Arnell, Leonard J Deftos, Anne Klibanski
• Journal: Endocrine practice : official journal of the American College of Endocrinology and the American Association of Clinical Endocrinologists (Endocr Pract) 2005 May-Jun Vol. 11 Issue 3 Pg. 184-9 ISSN: 1530-891X [Print] United States
• PMID: 16239205 (Publication Type: Case Reports, Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Diphosphonates
• Imidazoles
• Parathyroid Hormone-Related Protein
• Zoledronic Acid
• Pamidronate

Topics

• Aged
• Bone Marrow Neoplasms (metabolism, secondary)
• Brain Neoplasms (metabolism, secondary)
• Diphosphonates (therapeutic use)
• Fatal Outcome
• Humans
• Hypercalcemia (drug therapy, etiology)
• Imidazoles (therapeutic use)
• Immunoenzyme Techniques
• Immunohistochemistry
• Male
• Pamidronate
• Parathyroid Hormone-Related Protein (biosynthesis)
• Pituitary Neoplasms (pathology, radiotherapy)
• Rhabdomyosarcoma (metabolism, secondary)
• Sphenoid Sinus
• Zoledronic Acid