Paraganglioma. (section Endocrine Pathology)
Paraganglioma normally occurs in sites that parallel the sympathetic and parasympathetic chain ganglions. Common locations of paraganglioma include tumours of paraganglionic system in head and neck region like carotid body paraganglioma and jugulotypmanic paraganglioma. There are also paragangliomas that occur outside the usual distribution of sympathetic and parasympathetic paraganglia. Pathological diagnosis of paraganglioma depends on the characteristic histological features and immnohistochemical detection of neuroendocrine marker(s). Composite paragangliomas (paragangliomas with features of ganglioneuroma or ganglioneuroblastoma) are sometimes noted. The malignant potential of paraganglioma is difficult to be assessed. Assessment systems have been proposed in the pathology reporting of paraganglioma in order to predict the malignant behaviour of the tumour. In this context, proliferative activity obtained from Ki-67 immunohistochemical staining should be provided in the reporting of paraganglioma. Recent developments in molecular genetics have expanded the spectrum of disorders associated with paragangliomas. The relevant clinical impact in pathology is the role of pathologist in the detection of SDHB by immunohistochemistry in paraganglioma as SDHB mutations are strongly correlated with head and neck paraganglioma, presence of metastasis and poor prognosis. A high index of suspicion should be applied as paraganglioma occur in diverse sites. Also, awareness of the need of updated pathological and immunological data are essential for proper management of patients with paraganglioma.
Congress of the International Academy of Pathology 2014.
Medical and Health Sciences