Vagina
Malignant tumors
Melanoma

Reviewer: Shweta Gera, M.D. (see Authors page)
Editor: Arzu Buyuk, M.D.

Revised: 3 May 2016, last major update August 2014

Copyright: (c) 2002-2016, PathologyOutlines.com, Inc.

PubMed Search: Melanoma [title] vagina
Cite this page: Melanoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/vaginamelanoma.html. Accessed December 4th, 2016.
Definition / General
  • Melanoma originating in vaginal wall without involvement of vulva, uterine cervix or other surrounding structures (Gynecol Obstet 3:183)
  • Terminology
  • Also called primary malignant melanoma of vagina
  • Epidemiology
  • Melanomas arising from female urogenital tract occur primarily in vulva (95%) and vagina (3%)
  • Primary melanoma of vagina is extremely rare and aggressive
  • Constitutes less than 3% of vaginal cancers and only 0.3-0.8% of all melanomas in women (Gynecol Obstet 3:183)
  • Occurs mainly in postmenopausal women, sixth and seventh decades of life (J Chin Med Assoc 2011;74:376)
  • Rare cases in young patients (Int J Pathol 2009;7:102)
  • Sites
  • More commonly in the lower third of vagina and on anterior vaginal wall (Gynecol Obstet 3:183, J Chin Med Assoc 2011;74:376)
  • Etiology
  • Appears to originate from melanocytes present in vaginal mucosa (Gynecol Obstet 3:183)
  • Clinical Features
  • Vaginal bleeding or discharge (J Chin Med Assoc 2011;74:376)
  • Diagnosis
  • Based on biopsy/resection specimen with clinical history and imaging
  • Radiology Description
  • Small tumors can be difficult to assess on CT scan
  • The use of fluorodeoxyglucose (FDG) as a glycolytic indicator in tumor-altered metabolism in PET/CT study can aid in early diagnosis and staging
  • Prognostic Factors
  • Common sites of recurrence of vaginal melanoma are vagina, vulva, groin
  • Prognosis poorer than cutaneous melanomas
  • Five year survival rate of 13-19% is poor compared to vulvar and cutaneous melanomas
  • Fifty percent have positive lymph nodes, and nearly 20 percent have distant metastases at presentation
  • Mean survival is 8.5 months after recurrence (Gynecol Obstet 3:183)
  • Case Reports
  • 31 year old woman with primary amelanotic melanoma (Onkologie 2008;31:474)
  • Melanoma of vagina (Indian J Pathol Microbiol 2003;46:71)
  • Primary amelanotic melanoma (Int J Gynaecol Obstet 1989;29:159)
  • Treatment
  • Many different treatment modalities have been tested, but there is no standard therapeutic approach
  • Surgery provides local control; procedures include wide local excision, radical surgery (total vaginectomy with or without vulvectomy), pelvic extenteration
  • Sentinel lymph node biopsy (SLNB) provides important prognostic and staging data with minimal morbidity
  • Routine lymph node dissection is not recommended because morbidity is high, and prophylactic lymphadenectomy has not been shown to improve survival (J Chin Med Assoc 2011;74:376)
  • It is difficult to get negative surgical margins without pelvic exenteration due to multifocality and anatomic constraints
  • Surgery may be combined with radiotherapy or chemotherapy
  • Cytotoxic chemotherapy, IFNα, IL2, ipilimumab, and vemurafenib have been used in some cases (Gynecol Obstet 3:183)
  • IFN is used as adjuvant therapy in patients without disease but at high risk of systemic recurrence (J Chin Med Assoc 2011;74:376)
  • Clinical Images

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    Diffuse black pigmentation

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    Colposcopic findings

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    Mass in posterior wall

    Gross Description
  • Can have raised, ulcerated and irregular appearance (Gynecol Obstet 3:183)
  • Can present as polypoid lesion or a nodule
  • Usually pigmented with black to brown gross appearance, but 40% cases are amelanotic
  • Gross Images

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    Nodular mass

    Micro Description
  • Diffuse infiltration of large, pleomorphic, epithelioid and spindle shaped tumor cells in vaginal mucosa
  • Cells have eosinophilic cytoplasm, large oval or pleomorphic hyperchromatic nuclei, may have multiple nuclei with distinct nucleoli (J Clin Pathol 2004;57:986)
  • Amelanotic melanomas can be difficult to diagnose on histology
  • Junctional activity, if present. raises suspicion for melanoma (Int J Pathol 2009;7:102)
  • Immunohistochemical stains are helpful if no melanin pigment or junctional activity (Gynecol Obstet 3:183)
  • Micro Images

    Images hosted on PathOut server:

    Contributed by Dr. Mayank Gupta, Christian Medical College, Vellore (India)
    60 year old woman with nodular growth on left lateral vaginal wall

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    Cytokeratin (10x)

    HMB45 (10x)

    Melan-A (10x)



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    Atypical tumor cells

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    Melanin granules

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    H&E, S100, HMB45

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    HMB45+

    Cytology Description
  • Loose aggregates of large, pleomorphic, polygonal to spindle shaped tumor cells with ill-defined cytoplasmic borders, granular hyperchromatic nuclei and conspicuous nucleoli
  • Multinucleated tumor cells and mitoses can be seen (J Clin Pathol 2004;57:986)
  • Cytology Images

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    Loose aggregates of
    pleomorphic tumor cells

    Positive Stains
  • S100, HMB45, vimentin
  • Melanin pigment can be demonstrated with Fontana-Masson silver staining (J Clin Pathol 2004;57:986)
  • MelanA, tyrosinase, MiTF
  • Negative Stains
  • Cytokeratin, epithelial membrane antigen (EMA), desmin, myoglobin, smooth muscle actin, CD34, CD68
  • Amelanotic melanomas are negative for melanin pigment (J Clin Pathol 2004;57:986)
  • Molecular / Cytogenetics Description
  • NRAS mutations and KIT amplifications occur in both vaginal and vulvar melanomas
  • KIT mutations appear to be more specific for vulvar melanoma
  • BRAF mutations are absent in both vaginal and vulvar melanomas originating from the vulva or vagina (Mod Pathol 2014 Mar 7 [Epub ahead of print])