P. Tran Ba Huy

Natural History of Malignant Head and Neck Paragangliomas: Comparison of Malignant and Nonmalignant Cases

Objective: To report on 11 cases of malignant paragangliomas and provide further information on the natural history of these rare tumors. Design: Retrospective and comparative analysis. Participants: Retrospective and comparative analysis of 11 cases of malignant and of 131 cases of nonmalignant HNPGLs referred between 2001 and 2008 and followed up to June 2009 or death. Main Outcome Measures: Data were collected on sex, age at diagnosis, localization of the primary tumor, existence of extra-HNPGL and/or metastases (confirmed by histology and assessed by imaging, including CT-scan, MRI, and somatostatin receptor scintigraphy, FDG-PET, I-MIBG), catecholamine/metanephrine levels, family history, and genetic testing. Results: The 131 patients with nonmalignant HNPGLs were mostly female, had predominantly tympanojugular localizations (followed by carotid body and vagus nerve), had a mean age at diagnosis of 45 years, and had a rate of secreting and multicentric tumors of 5% and 20%, respectively. Eleven patients (7.7%) fulfilled the criteria of malignancy. They were of either sex, had mostly primary carotid body lesions, were a younger mean age (38 years) at diagnosis, and had a higher rate of secreting tumors and multicentric tumors (27% and 46%, respectively). Bone and lymph nodes were the main sites of metastases. No patient with a single tympanic PGL exhibited a malignant form. Conclusion: Malignancy seems greater in young patients presenting multicentric tumors, especially carotid body lesions, and is mostly related to mutations of the SDHB subunits. Accordingly, staging of disease in patients at risk should include whole-body scintigraphy and spine MRI. Malignancy is not necessarily associated with poor short-term prognosis.

Endoscopic Resection for Ethmoid Adenocarcinomas and Olfactory Neuroblastomas Involving the Anterior Skull Base

Objectives: The treatment of ethmoid malignant tumors combines a surgical combined approach with radiotherapy, at the cost of significant morbidity. Compared with the gold standard of craniofacial resection, the minimally invasive endoscopic resection may provide satisfactory results. The aim of this work is twofold: (1) to evaluate the quality of tumoral resection in the case of endoscopic anterior skull base resection and (2) to measure the morbidity of this technique. Patients and Methods: From 2000 to 2008, selected cases of patients presenting with ethmoid adenocarcinomas or olfactory neuroblastomas underwent surgery performed through an exclusive transnasal endoscopic approach with unilateral or bilateral removal of the anterior skull base. They were all preoperatively evaluated by CT scan and MRI, and then followed with repeated MRI. The study focused on analysis of the surgical margins and local control and on morbidity of the combined treatment. Results: Sixteen patients (11 with ethmoid adenocarcinoma and 5 with neuroblastoma) were operated on through a purely endoscopic approach with skull base removal; 12 of the cases also involved resection of the dura mater. The cribriform plate was invaded in 6 cases (37.5%), although it was not suspected from imaging data in 3 cases (sensitivity 50%). The only perioperative complication was 1 subdural hematoma, which was looked after. After radiotherapy, there was 1 case of encephalocele, which required a subfrontal approach, and 1 case of extended frontal brain radionecrosis. Local control was good except for 1 case with fulminant progression along the V nerve. One case is alive with metastases. Conclusion: Compared with craniofacial resection, these early results point out a minimal morbidity with dural resection. The rate of unsuspected invasion of the cribriform plate underlines the need for extensive resection. As far as local control is concerned, results require validation with long-term follow-up.