Lung tumor
Other carcinoma
Adenoid cystic carcinoma

Author: Roseann Wu, M.D. (see Authors page)

Revised: 14 April 2017, last major update February 2017

Copyright: (c) 2003-2017, PathologyOutlines.com, Inc.

PubMed Search: adenoid cystic carcinoma lung
Cite this page: Adenoid cystic carcinoma. PathologyOutlines.com website. http://pathologyoutlines.com/topic/lungtumorACC.html. Accessed October 20th, 2017.
Definition / general
  • #2 most common salivary gland-type carcinoma of lung
  • Usually in large bronchi, may involve the trachea
  • Prolonged course, but overall prognosis is poor
Essential features
  • See also Salivary glands - Adenoid cystic carcinoma
  • Primary pulmonary adenoid cystic carcinoma is rare, and metastasis from salivary glands must be excluded
  • Morphology is similar to adenoid cystic carcinomas in other sites, with cribriform, tubular and solid patterns
  • These tumors tend to arise in association with central airways and spread along neurovascular bundles
Terminology
  • Formally called bronchial adenoma, but now considered malignant
ICD-10 coding
  • Use code specific for location of tumor
  • C34.90 Malignant neoplasm of unspecified part of unspecified bronchus or lung
Epidemiology
  • Primary pulmonary adenoid cystic carcinoma is very rare, < 0.2% of lung cancers
  • Typically adults
Sites
  • Usually central / endobronchial but may be peripheral
Pathophysiology
  • Slow growing but persistent, with recurrences over years, potentially with metastasis to lymph nodes and distant sites
Etiology
  • Unclear, probably arise from submucosal bronchial glands
Clinical features
  • Obstructive symptoms, i.e., pneumonia, dyspnea, cough, wheeze, hemoptysis
  • Peripheral lesions asymptomatic
Diagnosis
  • Exclude metastasis from salivary glands
Radiology images

Images hosted on other servers:

Adenoid cystic carcinoma
obstructing right upper
lobar bronchus

Prognostic factors
  • Variable by tumor stage
Case reports
Treatment
Clinical images

Images hosted on other servers:

Various images

Gross description
  • Large, centrally located, polypoid, intrabronchial mass
  • May grow along bronchi (subepithelial) causing thickened bronchial wall
  • Circumscribed, soft, yellowish white
Gross images

Images hosted on other servers:

75 year old woman with 1 cm lung lesion

Microscopic (histologic) description
  • Propensity for tracking along nerves and cartilaginous plates → bronchial margins more often positive than in other lung cancers
  • Infiltrative growth, cribriform / cylindromatous (islands and nests, with luminal matrix), tubular (gland-like spaces) or solid (insular, with scant matrix) - usually a mix of patterns are seen
  • Defining features are pseudocysts (rounded extracellular space containing basal lamina), intercellular spaces, basal lamina and true glandular lumens (Hum Pathol 1982;13:916)
  • Monotonous, polygonal, basaloid cells
  • Absence of mitoses, nuclear pleomorphism, necrosis and hemorrhage in most cases; solid type may show more mitoses
Microscopic (histologic) images

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ACC show cribriform-like structures with mucus

Focal tubular structure in ACC

Various images

14 year old girl with 11 cm lung mass


Various images


75 year old woman with 1 cm lung lesion: H&E, TTF1

Cytology description
  • Cylinders or spheres of myxochondroid matrix within epithelial groups
  • Diagnosis more difficult if matrix is scarce, as in solid type
  • Cellular uniformity, distinct nucleolus, granular cytoplasm, distinct cell border, organoid cluster, hyaline globule and hyaline basement membrane material (J Pathol Transl Med 2015;49:511)
Cytology images

Images hosted on other servers:

Cytomorphology of pulmonary adenoid cystic carcinoma

Immunohistochemistry
  • Usually not necessary for diagnosis
  • Luminal cells: c-kit/CD117+, p63-, actin-
  • Basal (myoepithelial) cells: c-kit/CD117-, p63+, actin+
  • Tumor cells are usually positive for keratin and S100, and negative for neuroendocrine markers
  • Basement membrane material is positive for collagen type IV or laminin
Electron microscopy description
  • May show evidence of partial myoepithelial differentiation
Molecular / cytogenetics description
Differential diagnosis