Paragangliomas of the larynx

Paragangliomas of the Head and Neck: An Overview from Diagnosis to Genetics

Paragangliomas (PGL) develop from the parasympathetic system in the head and neck (HN) and arise primarily in four distinct areas: Carotid body, vagal, middle ear, and larynx. Globally, the diagnosis and morphologic features are the same regardless of anatomic site, however the incidence, frequency of genetic alterations/syndromes and differential diagnosis vary. It is now recognized that nearly 40% of all HN PGLs are hereditary, including a significant subset without a known family history. Now pathologists are central to the evaluation for diagnosis and further management of patients with HNPGLs. Specifically, SDHB immunohistochemical evaluation is an excellent screening tool to detect tumors with alterations in the SDH family of genes that represent the majority of hereditary cases in HNPGL. Similarly, SDHB immunohistochemical analysis allows for screening of PGL syndrome associated tumors (gastrointestinal stromal tumor (GIST), renal cell carcinoma (RCC), and pituitary adenomas) that have now been linked by their overlapping gene alterations. Awareness of the spectrum of these syndromes, and their associated tumors, positions the pathologist to augment patient care and surveillance.

Neuroendocrine neoplasms of the larynx: Advances in identification, understanding, and management

While 85-90% of laryngeal malignancies prove to be squamous carcinomas, the second most common tumour type found in the laryngeal region will prove to be a member of the family of neuroendocrine tumours. Laryngeal carcinoid tumours have a capacity for metastasis, and so are more aggressive tumours than their light microscopic features might imply--5-year survival rates are in the vicinity of 50%. Laryngeal atypical carcinoid tumours are lesions with a well-recognized capacity for local recurrence as well as metastasis, with a 5-year survival of just under 50%. Laryngeal small cell neuroendocrine carcinomas are particularly aggressive tumours, with a 5-year survival of no more than 5-10%. Laryngeal paragangliomas are lesions without any real capacity for metastasizing. Surgical excision is the mainstay of treatment of carcinoid tumours, atypical carcinoid tumours, and paragangliomas. Small cell neuroendocrine carcinomas are chiefly treated by way of radiation and chemotherapy; the role of adjuvant therapy in the treatment of atypical carcinoid tumours remains to be established.

A review of neuroendocrine neoplasms of the larynx: update on diagnosis and treatment

Neuroendocrine neoplasms of the larynx have been divided into those of epithelial or neural origin. The latter consist of paragangliomas while the epithelial origin group can be divided into the typical and atypical carcinoids and small cell neuroendocrine carcinomata, the latter consisting of the oat cell type, the intermediate cell type and the combined cell type. There are now over 500 cases of neuroendocrine neoplasms of the larynx in the literature. The diagnosis is primarily based on light microscopy, and, in some instances, it may be supported by special histochemical studies. It should be confirmed by immunocytochemical and/or ultrastructural investigation. The different biological behaviour of neuroendocrine neoplasms of the larynx makes a specific diagnosis of paramount importance, since treatment depends on diagnostic accuracy. Typical carcinoid is an extremely rare lesion. It is treated preferably by conservative surgery; elective neck dissection is not necessary because of the lack of lymph node metastases at diagnosis. Chemotherapy and/or radiotherapy have not been effective in the limited number of patients treated thus far. Prognosis is excellent with cure following surgery. Atypical carcinoid is the most frequent non-squamous carcinoma of the larynx. The mainstay of treatment is surgery. Elective neck dissection should be performed because of the high likelihood of cervical lymph node metastases. Primary radiation therapy with adjuvant chemotherapy is not indicated. The survival rate is 48 per cent at five years and 30 per cent at 10 years. Although the larynx is one of its most common extrapulmonary sites, small cell neuroendocrine carcinoma is still a rare tumour. Surgical results for this tumour have been disappointing and is reserved for cases of local relapse with no evidence of metastasis. Chemotherapy and radiotherapy currently appear to offer the least disabling and most effective forms of therapy. The two- and five-year survival rates are 16 per cent and five per cent, respectively. Paraneoplastic syndromes have occasionally been reported in association with carcinoid tumours (typical and atypical) and small cell neuroendocrine carcinoma. There have been also rare reports of an elevated neuropeptide serum level. Paraganglioma is the only laryngeal neuroendocrine neoplasm with a female preponderance (3:1). Confusion with atypical carcinoid has led to incorrect diagnosis and inappropriate classification schemes, erroneously suggesting that laryngeal paraganglioma has the potential for aggressive behaviour. Conservative surgery represents the treatment of choice; elective neck dissection is not necessary, and the prognosis is excellent.

Atypical carcinoid tumour of the larynx

The case of an atypical carcinoid tumour of the larynx is described in a 65-year-old man. This rare tumour may present diagnostic difficulties, but the diagnosis should be considered in a patient presenting with symptoms of local or referred pain and an apparently small, non-ulcerating supraglottic tumour. Immunocytochemistry has an important role in establishing the diagnosis. A very unusual feature of this case was positive staining for S-100 protein by sustentacular cells. Atypical carcinoid tumours do not respond well to radiotherapy so the primary treatment should be surgical resection.

Identification, classification, treatment, and prognosis of laryngeal paraganglioma. Review of the literature and eight new cases

This study details the clinicopathologic features of 62 cases of laryngeal paraganglioma (LP), including 54 acceptable cases identified in the literature (although clinical information is lacking on 7 of these) and 8 previously unpublished cases identified from the Registry of Otolaryngic-Endocrine Pathology at the Armed Forces Institute of Pathology. Demographic findings show that the overwhelming majority of cases affect women (41:14), mainly in the fourth to sixth decades of life (age range, 14 to 83 years; median, 44 years), with a prevalence in the supraglottic larynx. These neoplasms are treated by surgical resection and are benign. Despite the characteristic pathologic features associated with LP, it is sometimes confused with other neoplasms, particularly neuroendocrine carcinomas of the larynx, and this confusion leads to unfortunate designations such as malignant paraganglioma and metastasizing paraganglioma of the larynx. Judging from the cases reported in this study and those identified in the literature, we conclude that malignant biologic behavior associated with LP is extraordinarily rare (< 2%). Because of the misdiagnoses of LP, the prognosis associated with this entity has been skewed to suggest that LP may behave aggressively. This has led to the inappropriate classification of LP among the malignant categories of laryngeal neuroendocrine neoplasms. The goal of this study is to detail the features diagnostic of LP and to discuss the appropriate treatment, prognosis, and classification of these neoplasms.