Salivary glands

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Schematic showing the major salivary glands. (WC)

The salivary glands help digest food. ENT surgeons excise them if a malignancy is suspected.

The cytopathology of the salivary glands is covered in the Head and neck cytopathology article.

Normal salivary glands

Types of salivary glands

Types of glands:[1]

  1. Serrous - eosinophilic cytoplasmic granules, acinar arrangement - vaguely resembles the acinar morphology of the pancreas.
  2. Mucinous - light eosinophilic staining.

Identifying the glands

The three main glands:

  1. Parotid:
    • Serous glands - lower viscosity, acini (lobules).[2]
    • Most tumours in this gland are benign.
  2. Submandibular:
    • Serous and mucinous glands.
      • Serous ~90% of gland.
      • Mucinous ~10% of gland.
    • Serous demilunes = mucinous gland with "cap" consisting of a serous glandular component.
  1. Sublingual:
    • Mucinous glands.


  • Adipose tissue is found between the glands.
    • It increases with age.


Memory devices:

  • The parotid gland vaguely resembles the pancreas.
  • Submandibular = glands are mixed.


Benign tumours

Tabular form - adapted from Thompson[5]

Entity Architecture Morphology Cell borders Cytoplasm Nucleus DDx Other Image
Pleomorphic adenoma var. mixed pop.; must include: (1) myoepithelium, (2) mesenchymal stroma, and (3) epithelium (ductal cells) or chondromyxoid stroma var. var. (1) plasmacytoid adenoid cystic carcinoma occ. encapsulated,
mixed pop. of glandular,
myoepithelial and mesenchymal cells
PA. (WP)
Warthin tumour papillary,
cuboid (basal), columnar (apical) clearly seen eosinophilic, abundant unremarkable sebaceous lymphadenoma AKA papillary cystadenoma lymphomatosum
PCL. (WP/Nephron)
Basal cell adenoma var., islands surrounded
by hyaline bands, lesion encapsulated
basaloid subtle scant,
granular basal cell adenocarcinoma - -
Canalicular adenoma chains of cells cuboid or columnar subtle scant,
granular basal cell adenoma exclusively oral cavity, 80% in upper lip; IHC: p63-
CA. (WC)
Sialoblastoma var., islands surrounded
by loose fibrous stroma
basaloid subtle scant, hyperch. granular basal cell adenocarcinoma - -

Malignant tumours

Tabular form - adapted from Thompson[6]

Entity Architecture Morphology Cell borders Cytoplasm Nucleus DDx Other Image
Mucoepidermoid carcinoma cystic & solid epithelioid distinct fuffy, clear,
nuclei sm. SCC (?) IHC: p63+
Adenoid cystic carcinoma (AdCC) pseudocysts,
cribriform, solid,
hyaline stroma
epithelioid subtle scant,
pleomorphic adenoma, PLGA Stains: PAS+ (pseudocyst material), CD117+, cyclin D1+
AdCC. (WC/Nephron)
Acinic cell carcinoma (AcCC) sheets, acinar (islands) epithelioid clear granular abundant stippled, +/-occ. nucleoli adenocarcinoma not otherwise specified, oncocytoma of salivary gland Stains: PAS +ve, PAS-D +ve; IHC: S-100 -ve, p63 -ve
AcCC. (WC/Nephron)
Salivary duct carcinoma glandular, cribriform columnar subtle/clear hyperchromatic columnar metastatic breast carcinoma similar to ductal
breast carcinoma; male>female
SDC. (WC/Nephron)
Polymorphous adenocarcinoma (previously polymorphous low-grade adenocarcinoma) variable, often small
nests, may be targetoid
epithelioid indistinct eosinophilic ovoid & small with
small nucleoli
AdCC minor salivary gland tumour,
often in palate,
cytologically monotonous; IHC: S-100+, CK+, vim.+, GFAP+/-, BCL2+/-
PLGA. (WC/Nephron)
Epithelial-myoepithelial carcinoma nests (myoepithelial) with tubules (epithelial) epithelioid not distinct eosinophilic cytoplasm; epithelial: scant; myoepithelial: moderate focal clearing AdCC, pleomorphic adenoma rare
EMCa. (WC/Nephron)
Basal cell adenocarcinoma var., islands surrounded
by hyaline bands, lesion not encapsulated
basaloid subtle scant,
granular basal cell adenoma rare, usu. parotid gland, may arise from a basal cell adenoma
BCA. (WC/Nephron)



Benign parotid tumours

Oncocytic tumours

Clear cell tumours

Basaloid neoplasms

IHC overview


  • Usually has limited value.


  • Luminal markers: CK7, CK19, CAM5.2 (LMWK).
  • Basal markers: p63, HMWK, CK14.
  • Myoepithelial markers: calponin, actin.
  • Uncommitted: S-100.


  • p63 and S-100 are sometimes call myoepithelial.


  • Calponin, S-100, Ki-67 may be useful as per Nagao et al.[8]
  • Most salivary gland tumours are p40 positive and p63 positive; polymorphous adenocarcinoma is p63 positive and p40 negative.[9]


General DDx:

  • Inflammation.
  • Neoplasm.
  • Ductal obstrution.

Chronic sialadenitis

Salivary gland mucocele

Pleomorphic adenoma


Basal cell adenoma


  • ~2% of salivary gland tumours.
  • May be multifocal.
  • Usually parotid gland, occasionally submandibular gland.
  • Female:male = ~2:1.
  • May be seen in association with dermal cylindromas in the context of a genetic mutation.[10]
  • Malignant transformation - rarely.



  1. Basal component.
    • Basophilic cells - key feature.
    • Usu. in nests.
    • Large basophilic nucleus.
    • Minimal-to-moderate eosinophilic cytoplasm.
  2. Stromal cells.
    • Plump spindle cells without significant nuclear atypia - distinguishing feature.
      • Stromal cell nuclei width ~= diameter RBC.
    • Dense hyaline stroma.
  3. Tubular component.
    • Within basal component, may be minimal.
  4. Lesion is encapsulated - key feature.


  • No chondromyxoid stroma.
  • Neoplastic cells embedded in stroma ("stromal invasion") = basal cell adenocarcinoma.
    • Basal cell adenocarcinoma may be cytologically indistinguishable from basal cell adenoma, i.e. "bad" architecture makes it a basal cell adenocarcinoma.




  • Luminal stains +ve: CK7 +ve, CAM5.2 +ve.
  • p63 +ve -- basal component.
  • S-100 +ve -- spindle cells in the stroma.

Canalicular adenoma

Warthin tumour

Sebaceous adenoma

Sebaceous lymphadenoma

Oncocytoma of the salivary gland

  • AKA salivary gland oncocytoma.


One approach:

  • Differentiate -- luminal vs. myoepithelial vs. basal (mucoepideroid).

Mucoepidermoid carcinoma

Acinic cell carcinoma

Adenoid cystic carcinoma

Note: The breast tumour is dealt with in adenoid cystic carcinoma of the breast.

Salivary duct carcinoma

Intraductal carcinoma of the salivary gland

Polymorphous adenocarcinoma

  • Abbreviated PAC.
  • Previously known as polymorphous low-grade adenocarcinoma, abbreviated PLGA.

Carcinoma ex pleomorphic adenoma

  • Abbreviated Ca ex PA.

Epithelial-myoepithelial carcinoma

Basal cell adenocarcinoma

Sebaceous carcinoma

It is similar to the tumour found in the skin.

Hyalinizing clear cell carcinoma

See also


  3. URL: Accessed on: 19 August 2011.
  4. URL: Accessed on: 19 August 2011.
  5. Thompson, Lester D. R. (2006). Head and Neck Pathology: A Volume in Foundations in Diagnostic Pathology Series (1st ed.). Churchill Livingstone. pp. 295-319. ISBN 978-0443069604.
  6. Thompson, Lester D. R. (2006). Head and Neck Pathology: A Volume in Foundations in Diagnostic Pathology Series (1st ed.). Churchill Livingstone. pp. 325-357. ISBN 978-0443069604.
  7. 7.0 7.1 7.2 Chhieng, DC.; Paulino, AF. (Dec 2002). "Basaloid tumors of the salivary glands.". Ann Diagn Pathol 6 (6): 364-72. doi:10.1053/adpa.2002.37013. PMID 12478487.
  8. Nagao, T.; Sato, E.; Inoue, R.; Oshiro, H.; H Takahashi, R.; Nagai, T.; Yoshida, M.; Suzuki, F. et al. (Oct 2012). "Immunohistochemical analysis of salivary gland tumors: application for surgical pathology practice.". Acta Histochem Cytochem 45 (5): 269-82. doi:10.1267/ahc.12019. PMID 23209336.
  9. Sivakumar N, Narwal A, Pandiar D, Devi A, Anand R, Bansal D, Kamboj M (February 2022). "Diagnostic utility of p63/p40 in the histologic differentiation of salivary gland tumors: A systematic review". Oral Surg Oral Med Oral Pathol Oral Radiol 133 (2): 189–198. doi:10.1016/j.oooo.2021.07.010. PMID 34518135.
  10. Choi, HR.; Batsakis, JG.; Callender, DL.; Prieto, VG.; Luna, MA.; El-Naggar, AK. (Jun 2002). "Molecular analysis of chromosome 16q regions in dermal analogue tumors of salivary glands: a genetic link to dermal cylindroma?". Am J Surg Pathol 26 (6): 778-83. PMID 12023583.
  11. URL: Accessed on: 25 October 2011.