Chemodectomas
Etiology
- derived from neural crest tissue of the second branchial arch associated with either cranial nerve IX or X.
- also called glomus tumors or paraganglioma
- pheochromocytomas that develop in paraganglia other than adrenal medulla are designated paragagliomas
Pathology
- Histologically benign tumors resembling the parent tissue
- criterion of malignancy is based on clinical progression rather than histology
Clinical Presentation
- lesions are rare before age of 20
- originate anywhere glomus bodies are found
Routes of Spread
- slow growing but can be problematic due to their location
- low potential for metastatic disease
Diagnostic Studies
- biopsy can lead serious hemorrhage due to their high vascularity
Treatment
Surgery
Site of Origin | Surgery | Comments |
gloumus tympanicum | approach through the eardrum | conductive lose may be correctable |
glomus jugulare | • mastoidectomy or • subtotal temoral bone resection |
surgery is reserved for radiation failure |
carotid body | standard neck incision |
- LCR: local control rate
- major risks of surgery include
- hemorrhage
- CN injury
Radiation
- 45 Gy in 1.8 Gy/fraction to tumor volume
Chemotherapy
- not sensitive to chemotherapy
Outcome
from Devita 7th, p 722; and Gunderson 2nd, p 556
Tumor location | Local Control w/ Surgery | Local Control w/ RT |
temporal bone | 89% to 95% at 5 years | 91% |
carotid body | 89% at 7 years | 97% |
Bibliography
1. Cox J, Ang K. Radiation Oncology: rationale Technique Results. 8th ed. New York: Mosby, 2003.
2. Gunderson L, Tepper J: Clinical Radiation Oncology. 2nd ed. China: Elsevier 2007.
3. Devita V, Hellman S, Rsenberg S: Cancer: Principles and practice of Oncology. 7th ed. Philadelphia: Lippincott, 2005.
page revision: 3, last edited: 06 Jul 2007 03:25