Malignant melanoma

oral manifestation of malignant melanoma

1. Malignant Melanoma
Presented by: Stéphanie Chahrouk
Introduction
 Malignant Melanoma Accounting for about 3 to 4% of all diagnosed skin cancers,
 melanoma begins in the melanocytes cells within the epidermis that give skin its color.
 The incidence is rising by 3% a year
 Melanoma is a cancer of melanin producing cells
 It can arise from
 Skin
 Mucosa of oropharynx, nasopharynx, proximal esophagus, anorectum ,female genitalia
 Eyes-Retina, uvea
 Leptomeninges (arachnoid, piamater)
AETIOLOGY
 The cause is unknown.
 Excessive exposure to sunlight
 Genetic predisposition
RISK FACTORS FOR MELANOMA
 Large numbers of benign naevi
 Clinically atypical naevi
 Severe sunburn
 Early years in a tropical climate
 Family history of MM
Clinical features
 Occur anywhere on the skin
 Females (commonest is lower leg)
 Males (back).
 Early melanoma is pain free.
 The only symptom if present is mild irritation or itch.

2. AIDS IN CLINICAL DIAGNOSIS
GLASGOW SYSTEM
Major:
 Change in size
 Irregular pigment
 Irregular outline
Minor:
 Diameter >6mm
 Inflammation
 Oozing/bleeding
 Itch/altered sensation
AMERICAN ‘ABCDE’ SYSTEM
 A symmetry
 B order
 C olour
 D iameter
 E xamination

3. 1- SUPERFICIAL SPREADING


•–70% of cases
The most common type of MM in the white-skinned population
•–lower leg in females and back in males
Commonest sites
In early stages may be small, then growth becomes irregular
TYPES OF MELANOMA
1-Superficial spreading Malignant melanoma
2-Nodular melanoma
3-Letingo maligna melanoma
4-Acral malanoma

4. 2- Nodular Melanoma
Common in males
Trunk is a common site
Rapidly growing
Usually thick with a poor prognosis
Black/brown nodule
Ulceration and bleeding are common

3- ACRAL LENTIGINOUS MELANOMA
In white-skinned population this accounts for 10% of MMs, but is the commonest MM in
nonwhite-skinned nations
Found on palms and soles
Usually comprises a flat lentiginous area with an invasive nodular component

5. 4- SUBUNGAL MELANOMA
Rare
Often diagnosed late – confusion with benign subungal naevus, paronychial infections, trauma
Hutchinson’s sign – spillage of pigment onto the surrounding nailfold

5- LENTIGO MALIGNA MELANOMA
Occurs as a late development in a lentigo maligna
Mainly on the face in elderly patients
May be many years before an invasive nodule develops

6. Diffenrential diagnosis !!
 Superficial spreading melanomas
 Benign melanocytic naevi
 Nodular melanomas
 Vascular tumor
 Histiocytoma
 Latingo maligna melanoma
 Seborrhic keratoses


Characteristic histologic findings include the following:

 Cytologic atypia, with enlarged cells containing large, pleomorphic, hyperchromic
nuclei with prominent nucleoli
 Numerous mitotic figures
 Pagetoid growth pattern with upward growth of the melanocytes

7. Primary Oral Mucosal Melanoma (POMM)
 Aggressive and rare disease
 Like cutaneous melanomas, they arise from melanocyte precursors and nevus cells.
Mucosal melanomas are much
 Less common than cutaneous melanomas.
 no sex predilection
 Occur in individuals, generally older than 50 years, than do skin melanomas.
Sites:
o Most common sites: the hard palate and upper gingiva,
o Less common sites: Followed by mandibular gingiva, lip mucosa, and other oral
sites.
Its appearance
 membranes follows the same ABCD recognition algorithm as skin melanomas
 Asymmetry, border irregularity, color variegation, and diameter enlargement

8. Clinical types
 of cutaneous melanoma—superficial spreading, nodular, and acral lentiginous— may also
occur on mucous membranes.
 However, lentigo maligna and lentigo maligna melanoma do not.
Rate: rapid advancement and spread.
Prognosis: has little relevance to treatment or prognosis.

!!The thin lamina propria and the absence of a reticular dermis allow mucosal melanomas to
spread peripherally and to gain access to the richest lymphatic and vascular networks more
quickly.

9. Physical:
 Because oral malignant melanomas are often clinically silent, they can be confused with a
number of asymptomatic, benign, pigmented lesions.
 Oral melanomas are largely macular, but nodular and even pedunculated lesions occur.
 Pain, ulceration, and bleeding are rare in oral melanoma until late in the disease.
 The pigmentation varies from dark brown to blue-black; however, mucosa-colored and
white lesions are occasionally noted, and erythema is observed when the lesions are
inflamed.
Causes:
 The cause of oral melanoma or melanoma of any mucosal surface remains unknown,
 No link has been established with denture wearing, chemical or physical trauma, or
tobacco use.
 Melanocytic lesions, such as blue nevi, are more common on the palate.
 Oral blue nevi are not reported to undergo malignant transformation.
Differentials to be considered
 Addison Disease
 Blue Nevi
 Ephelides (Freckles)
 Kaposi Sarcoma
 Oral Nevi
 lymphangioma
Other Problems to be Considered:
 Amalgam tattoo
 Graphite tattoo
 Oral melanotic macule
 Peutz-Jeghers syndrome
 Physiologic pigmentation

10. Histologic Findings:
oral melanomas have characteristics of the acral lentiginous (mucosal lentiginous) and,
occasionally, superficial spreading types.
 proliferation of neoplastic melanocytes
 variable phenotypes epithelioid, spindle, and plasmacytoid tumor cells
 arranged in a sheet-like, organoid, alveolar, solid, or desmoplastic architecture.
Tumors with mixed cell phenotypes
 are more aggressive
 associated with a higher prevalence of vascular invasion and metastasis.
 Usually the neoplastic proliferation lies along the junction between the epithelial and
lamina propria, but in advanced, ulcerated lesions, this might be difficult to be detected.
 Melanin pigment is noted in almost 90% of lesions
The melanoma cells have
 large nuclei, often with
 prominent nucleoli, and show
 nuclear pseudoinclusions due to nuclear membrane irregularity.
The abundant cytoplasm may be uniformly
 eosinophilic or
 optically clear.
 cells become spindled or neurotize in areas.
Leukocyte common antigen and Ki-1 are used to identify the lymphocytic lesions.
Cytokeratin markers can be used to help in the identification of epithelial malignancies.

12. Staging:
 The American Joint Committee on Cancer does not have published guidelines for the
staging of oral malignant melanomas. Most practitioners use general clinical stages in the
assessment of oral mucosal melanoma as follows:
 Stage I- Stage II- Stage III
 Tumor thickness and lymph node metastasis are reliable prognostic indicators.
 Lesions thinner than 0.75-mm rarely metastasize, but they do have the potential to do so.
On occasion, a small primary lesion is discovered after a symptomatic lymph node is
harvested.


StageI–Localizeddisease
neoplasticnestsatthe
epithelial/laminapropria
junction.
StageII–Regionallymphnode
metastasis
invasivemelanoma with
neoplasticcellsdetectedinthe
laminapropria
StageIII–Distantmetastasis
deeplyinvasivemelanomaupto
thebonestructures.

13. Treatment
 Complete surgical resection.
 In patients with recurrent disease and without distant disease, a second surgical procedure is
considered as the best option
 Malignant melanoma has been regarded as a radioresistant tumor, radiotherapy has become
utilized as adjuvant treatment, considering the tumor heterogeneity.
 no systemic therapy has been recognized as effective for metastatic mucosal melanoma
Prognosis
 poor prognosis
 Few long-term survivors.