Paragangliomy léčené na Klinice ORLa chirurgie hlavy a krku1. LF UK v letech 1990-2000

Paragangliomas Treated atthe Clinic for ENT and Surgery of Head and Neck of the First Medical Faculty Charles Universityin 1990-2000

Paragangliomas or chemodectomas are according to their origin classified asneuroectodermal tumours. As to their basis and structure they are near to ganglioneuromas whichis differentiated near to the structure of the adrenal medulla. In the ENT area, contrary to classicalpheochromocytoma, we encounter the achromaffine extraadrenal variant which develops fromtissue of sympathetic and parasympathetic ganglia. In the area of head and neck evidence of pressorsubstances produced by tumours is rare in the same may as malignant variants of these tumours.Macroscopically glomus tumours can be characterized as encapsulated, lobular, redish to violetcoloured formations depending on the vascularization of the tumour. Microscopically similarly asin paraganglia there are two types of cells, the main (eptheloid) - type I and sustentacular - type II.The basic structural unit is a defined agglomeration of main cells which is called Zellballen. Theextraadrenal variant of the tumour is characterized in addition to inadequate argentaffinity bya good and sharply defined separation of alveolar tumourous foci connective tissue strips with widesinusoid capillaries. Only rarely it is possible to observe a periteliomatous pattern. In the microscopic structure of these tumours participates the axial ending of a nonmyelinized nerve immersedinto cells of the Schwann type. When investigating the incidence of glomus tumours within theframework of genealogical studies a certain hereditary relationship was found whereby the prob-able transfer between different generations is autosomally dominant. There is also an increasedpredisposition of the incidence of paragangliomas in women and an increased incidence (up to 50%)of multiple incidence of tumours in different affected members of the family, while in patientswithout a family load of the basic disease the multifocal incidence is slightly lower, ca by 10%. Theauthors observed also a tendency of the multiple incidence of these tumours in conjunction withadvancing age of the patients and a tendency of a possibly higher incidence of paragangliomas inchildren of affected men. Genetic predisposition of familial glomus depends on one allele. The mostfrequent familial type of chemodectoma is the glomus caroticum tumour (up to 80%). A typicalmanifestation of paragangliomas is slow progression of growth. The first clinical signs of theseneoplasias are usually observed several years after development of the tumour. Only about 3% ofthese cases can be considered malignant, in particular because of metastases. These tumours areknown by their very slow locoregional spread.The authors present a group of patients examined and treated at a clinical ENT department in thecourse of 10 years on account of the diagnosis of paraganglioma. The group comprises a total of 15patients, incl. 11 women (73.3%) and 4 men (20.7%). The average age of the operated patients was37.5 years, range 20 tp 73 years. As to sites, tympanojugular chemodectomas were found in 33.3%,a glomus vagale tumour in five instances (26.7%), a paraganglioma of the carotid sinus was provedin five instances (33.3%) and in one case the finding was described as a metastasis of a paraganglioma which was originally in the aortic arch and which was already previously treated at a surgicaldepartment. In two patients (13.3%) anamnestically multiple incidence of paragangliomas wasdescribed incl. one female patient who was treated previously at another department on account ofchemodectoma at another site, primarily by radiotherapy with two relapses in this area which weresubsequently treated by a combination of surgery embolization and radiotherapy. In anotherpatient in the past repeatedly surgery was used at the same site for of chemodectoma, in anotherdepartment. However ther was multicentric incidence, i.e. first a glomus vagale tumour and latera carotid paraganglioma which was confirmed on operation and histological examination. Thepreoperative diagnosis of glomus tumours was based on a detailed case-history, clinical picture andimaging methods. In the cervical region ultrasonography was used, digital subtraction angiographytwice supplemented by CT examination. In the area of the cranial base always digital subtractionangiography was used supplemented by CT or possibly MR examination. In three patients withsuspected endocrine activity catecholamine breakdown products were examined in urine and inone case raised levels were found in a female patient with netastases of an aortal paraganglioma inthe cervical region. All patients were treated primarily by radical removal of the tumour.After surgery in none of the patients actinotherapy was indicated nor treatment with Leksell’sgammaknife. In conjunction with surgery no inflammatory complications were observed in the areaof the operational field. Postoperative clinical complications involved discontinuation of anatomical structures which the tumour infiltrated and which had to be removed to achieve a primaryradical operation. The follow-up in the investigated patients is on average 2.8 years with a range of7 months to 10 years and during the follow-up period no relapse of the basic disease was observedin conjunction with the administered treatment.

Key words:
paragangliomas, surgical treatment, complications, Leksell’s gammaknife, actinotherapy.