Oral cavity
Other malignancies

Author: Nat Pernick, M.D. (see Authors page)

Revised: 16 March 2017, last major update November 2013

Copyright: (c) 2002-2017, PathologyOutlines.com, Inc.

PubMed Search: melanoma[title] oral cavity

Cite this page: Melanoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/oralcavitymelanoma.html. Accessed April 30th, 2017.
Definition / general
  • Rare; annual incidence of 1.2 cases per 10 million; more common in Japanese, black Africans, Native Americans and Hispanics
  • Median age 61 years, 78% men
  • Differs from cutaneous melanoma due to lack of association with sun damage, family history or atypical nevi, and difference in prognostic factors
  • Nodal and distant metastases are common
  • References: Am J Surg Pathol 2001;25:782, Am J Surg Pathol 2002;26:883
Prognostic factors
  • Extremely poor prognosis, with median survival 2-3 years; some lower grade tumors without vascular invasion had median survival of 8 years
  • Poor prognostic factors: vascular invasion, polymorphous tumor cell population and necrosis
  • No prognostic value: tumor thickness, ulceration and level of invasion
Case reports
Gross description
  • Mucosa covering maxillary bone (62%), labial mucosa (13%) and lower gingiva (8%)
  • Usually flat, erythematous or pigmented, less commonly presents as a mass
Microscopic (histologic) description
  • Mean 3 mm thick; pigmented or frequently amelanotic; morphology includes epithelioid, fusiform and polymorphous cells
  • Some tumor giant cells in almost all cases; 90% have associated melanoma in situ; usually mitotic figures
  • Frequent ulceration, necrosis, vascular invasion and perineural invasion; may have desmoplastic features, particularly if lower lip
Microscopic (histologic) images
Images hosted on PathOut server:

PAP - COW #419

Giemsa - COW #419

HMB45 (cell block) - COW #419

Nests and nodules
of tumor cells with
melanin pigments
- COW #419

Tumor cells with
extensive necrosis
and melanin pigments
- COW #419

Images hosted on other servers:

In situ and invasive

H&E and stains

Positive stains
Negative stains
Differential diagnosis
  • Amelanotic melanomas: large cell lymphoma, poorly differentiated carcinoma
Board review questions
What do primary mucosal melanoma and cutaneous melanoma have in common:

A. Both commonly have BRAF mutations.
B. Both use the same staging criteria.
C. Sun exposure is a risk factor for both.
D. They have a similar prognosis.
E. They have the same immunohistochemical profile.
Board review answers
E. They have the same immunohistochemical profiles.

Primary mucosal melanomas share histologic and immunohistochemical features with cutaneous melanomas, but differ in terms of risk factors, aggressiveness, molecular profiles and staging criteria.