Lung
Other tumors
Paraganglioma
Author: Roseann I. Wu, M.D., M.P.H.
Last author update: 1 December 2015
Last staff update: 7 June 2023
Copyright: 2003-2024, PathologyOutlines.com, Inc.
PubMed Search: Paraganglioma [title] lung
Table of Contents
Definition / general | Essential features | Terminology | Epidemiology | Sites | Etiology | Clinical features | Diagnosis | Laboratory | Radiology description | Radiology images | Prognostic factors | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Cytology description | Positive stains | Negative stains | Electron microscopy description | Molecular / cytogenetics description | Differential diagnosisCite this page: Wu R. Paraganglioma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/lungtumorparaganglioma.html. Accessed December 3rd, 2024.
Definition / general
- Very rare neuroendocrine tumor in lung
- Usually benign
- Metastases to lung are more common than a lung primary
Essential features
- Classic "zellballen" / organoid pattern with S100+ sustentacular cells, similar to pheochromocytoma
- Primary pulmonary paraganglioma is extremely rare and requires ancillary studies to differentiate from carcinoid tumor
- Considered malignant if metastasis is demonstrated
Terminology
- Extra-adrenal pheochromocytoma
- Historical names have included glomus tumor, carotid body-like tumor, chemodectoma (Thorac Cardiovasc Surg 2009;57:375)
Epidemiology
- Extremely rare (< 25 case reports)
- Thoracic paragangliomas comprise 1 - 2% of all paragangliomas (including pheochromocytomas)
- Middle aged males predominate in sporadic cases, but middle aged females predominate in MEN 2 syndromes and present earlier
Sites
- Various organs
- Thoracic paragangliomas mostly in mediastinal compartment but can also be primary intrapulmonary mass
- Rarely may be endobronchial
Etiology
- Arise from paraganglion cells; neural crest origin
- Intrapulmonary paragangliomas may arise from paraganglia-like structures in interstitium
Clinical features
- Mostly asymptomatic or non-specific symptoms
- Obstructive symptoms if endobronchial
- May show symptoms depending on specific neuropeptide production, if functional (i.e. hypertension from elevated norepinephrine)
- May invade bronchus and metastasize to lymph nodes
Diagnosis
- Usually solitary nodules discovered incidentally
- Diagnosis requires histologic examination with ancillary studies
Laboratory
- May show elevated serum levels of specific neuropeptide
Radiology description
- Xray: abnormal lung shadow
- CT: well circumscribed to slightly irregular, solid mass
- PET scan: may show FDG avid mass
Radiology images
Images hosted on other servers:
Pulmonary nodule
Prognostic factors
- Mostly benign behavior
- If metastases, call "malignant paraganglioma", which may show reduced sustentacular cells and decreased neuropeptide markers
- Features most predictive of malignancy: extra-adrenal location, coarse nodularity of tumor, confluent tumor necrosis, absence of hyaline globules (Hum Pathol 1990;21:1168)
Case reports
- 37 year old woman with pulmonary paraganglioma manifesting as an endobronchial mass (Korean J Radiol 2008;9:87)
- 38 year old woman with primary paraganglioma of the lung (J Int Med Res 2012;40:1617)
- 69 year old woman with pulmonary metastases in a bilateral carotid body paraganglioma (Interact Cardiovasc Thorac Surg 2004;3:578)
- Middle mediastinal paraganglioma mimicking metastatic neuroendocrine tumor (Ann Thorac Surg 2015;100:702)
Treatment
- Surgical resection (local excision or lobectomy)
Gross description
- Solitary or multiple, usually peripheral mass, often microscopic but may be several centimeters
- Round to lobulated, well circumscribed but may show infiltrating border
- Grey, pink, tan to orange color, may show areas of hemorrhage
Gross images
Images hosted on other servers:
Bulging mass
Microscopic (histologic) description
- Organoid, trabecular and alveolar patterns, variable "zellballen"
- Zellballen pattern (nested islands of chief cells) with inconspicuous sustentacular cells and capillary network at periphery (Am J Surg Pathol 2004;28:825)
- Variable nuclear size, some cells with pleomorphism or hyperchromasia
- Round to oval nuclei, prominent nucleoli, clear to eosinophilic and finely granular cytoplasm
- Nuclear pseudoinclusions, intercellular hyaline globules, spindle cell or oncocytic changes may be seen
- Presence of mitoses and vascular invasion not helpful for distinguishing benign and malignant
- Necrotic foci may be seen
- May show partly infiltrating border of lymphocytes
Microscopic (histologic) images
Images hosted on other servers:
Histology of nodule
Lung tumor cells
Cytology description
- Papillary-like clusters of epithelioid cells with round to oval nuclei, evenly dispersed chromatin, micronucleoli, occasional anisonucleosis (Acta Cytol 2001;45:459)
- Abundant cells with round or oval nuclei and marked anisokaryosis with tendency to form acini or follicular structures
- Binucleation and intranuclear cytoplasmic inclusions (Acta Cytol 1988;32:386)
Positive stains
- CD56, synaptophysin, chromogranin, NSE, some neurofilament (chief cells)
- S100 (sustentacular cells)
Electron microscopy description
- Dense core granules with internal, submembranous, eccentric halo emanating in a bubble-like fashion ("norepinephrine-type" granules)
Molecular / cytogenetics description
- Mutations in RET gene on chromosome 10
Differential diagnosis
- Carcinoid tumor: cytokeratin+, TTF1+; ribbons, festoons, rosettes
- Metastatic tumors
- Pulmonary gangliocytic paraganglioma: cytokeratin+, 3 cell types (endocrine, ganglion-like, spindle-shaped)
