pigmented lesion

Pigmented lesions of oral cavity

طب فم \ خامس اسنان
د. وائل م(8)
26\ 4\ 2017


Pigmented lesions are commonly found in the mouth. Such lesions represent a variety of clinical entities, ranging from physiologic changes to manifestations of systemic illnesses and malignant neoplasm

Oral pigmentation may be exogenous or endogenous in origin.

Exogenous pigmentation is commonly due to foreign-body implantation in the oral mucosa.

Endogenous pigments include melanin, hemoglobin, hemosiderin and carotene.

The color of oral pigmentation can vary depending on the quantity and depth or location of the pigment. Generally, the surface shows brown pigmentation and those located deeper are black or blue.

Pigmented lesions caused by increased melanin deposition may be brown, blue, grey or black, depending on the amount and location of melanin in the tissues


Differential diagnosis of pigmented lesions of oral cavity


The history should include the onset and duration of the lesion


The presence of associated skin hyperpigmentation


The presence of systemic signs and symptoms


Use of prescription and nonprescription medications,


Smoking habits


The number, distribution, size, shape and colour of intraoral pigmented lesions should be assessed.


Clinical tests -diascopy and radiography and laboratory investigations


Diffuse And Bilateral Pigmentation
Physiologic (Racial) Pigmentation
Greater melanocytic activity
The colour ranges from light to dark brown.
The attached gingiva is the most common intraoral site of such pigmentation
Pigmentation of the buccal mucosa, hard palate, lips and tongue may
pigmentation is asymptomatic
Physiologic (Racial) Pigmentation









Phy-siological pigmentation increases with age, and color intensity can be influenced by smoking, hormones and systemic medications

Chloasma

Peutz-Jeghers Syndrome

Peutz-Jeghers Syndrome


Rare genetic disorder associated with mutation of the LKB1 gene


The melanotic spots of Peutz-Jeghers syndrome are characteristically small and multiple


Obvious around the lips.


The melanotic spots do not require treatment and are not associated with increased risk of melanoma.





Black-to-brown spots of less than 1 mm in size are typically localized on the lower lip and in the perioral are

Peutz-Jeghers Syndrome

Characterized by pigmented mucocutaneous macules,

intestinal hamartomatous polyposis and an increased risk of cancer in many organs, including the small intestine, colon, stomach, pancreas, breast and genital tract

Gastric polyps

Mucocutaneous symptoms

Addisons disease

Addison’s disease or primary hypoadrenalism



Progressive bilateral destruction of the adrenal cortex by autoimmune disease, infection or malignancy





Oral involvement presents as diffuse brown patches on the gingiva, buccal mucosa, palate and tongue





Addison’s disease can be fatal if left untreated


Oral mucosal pigmentation associated with Addison’s disease develops and progresses during adult life






Usually accompanied by systemic manifestations including weakness, nausea and vomiting, abdominal pain, constipation or diarrhea, weight loss and hypotension

ADDISONS DISEASE

The increased production of ACTH induces melanocyte-stimulating hormone, which results in diffuse pigmentation of the skin and oral mucosa
The disappearance of oral lesions may follow the treatment of the underlying condition

Heavy Metal Pigmentation

Increased levels of heavy metals in the blood represent a known cause of oral mucosal discolouration
common cause for such increased levels is occupational exposure
In children, possible sources of exposure include lead-contaminated water or paint and mercury- or silver-containing drugs

Lead, bismuth, mercury, silver, arsenic and gold ingestion and occupational exposure leads to pigmentation
Diffuse mucosal ulceration and a metallic taste may also be noted.

Lead line of gingiva

Bismuth line of gingiva

Kaposi’s Sarcoma
Multifocal vascular malignancy
Diagnostic of AIDS progression
KS in the oral mucosa most commonly affects the hard palate, gingiva and tongue
Early lesions appear as flat or slightly elevated brown to purple lesions that are often bilateral.
Definitive diagnosis requires biopsy
Advanced lesions appear as dark red to purple plaques or nodules that may exhibit ulceration, bleeding and necrosis

Kaposi sarcoma

Kaposi sarcoma (KS) is a cancer that develops from the cells that line lymph or blood vessels.
Appears as tumors on the skin or on mucosal surfaces
Kaposi sarcoma tumors usually manifest as bluish-red or purple bumps
Options for treatment include antiviral combination chemotherapy,
cryotherapy, or radiation therapy.

Drug-Induced Pigmentation

The pathogenesis of drug-induced pigmentation varies, depending on the causative drug
It can involve accumulation of melanin, deposits of the drug or one of its metabolites
Mucosal discolouration associated can be described as blue–grey or blue–black
In most cases only the hard palate is involved
Laboratory studies have shown that these drugs may produce a direct stimulatory effect on the melanocytes.
Cotrimazole was the most common drug associated to oral pigmentation followed by tetracycline

Drugs Associated With Oral Pigmentation

Post-inflammatory Pigmentation
Long-standing inflammatory mucosal diseases, such as oral lichen planus , pemphigus or pemphigoid can cause mucosal pigmentation
The pathogenesis of post inflammatory pigmentation remains unclear
Clinically, multiple brown–black pigmented areas are noted adjacent to reticular, erosive or vesicular lesions.
Generally, the resolution of the inflammatory process allows the cessation of oral pigmentation.

Reticular lichen planus with pigmentation

Smoker’s Melanosis
Increased production of melanin, provide a biologic defence against the noxious agents present in tobacco smoke
Smoker’s melanosis occurs in up to 21.5% of smokers.
The intensity of the pigmentation is related to the duration and amount of smoking
The brown–black lesions most often involve the anterior labial gingiva followed by buccal mucosa



Characterized by discrete or coalescing multiple brown macules that usually involve the attached mandibular gingiva on the labial side

Unlike heavy-metal pigmentation, which affects the free gingival margin, smoker’s melanosis develops on the attached gingiva



Diffuse grayish white pigmentation of palate with red pin point areas- smokers palate

Focal Pigmentation

Hemangioma
Hemangioma is a benign proliferation of the endothelial cells that line vascular channels.
Hemangioma regresses as the patient ages
The lesion may be flat or slightly raised
Varies in color from red to bluish purple depending on the type of vessels involved

Vascular malformation

Vascular malformation is a structural anomaly of blood vessels without endothelial proliferation
Vascular malformation persists throughout life

Haemangioma

VM






In the mouth, the tongue is the most common site of occurrence, and the clinical features are similar for hemangioma and vascular malformation

Varix and Thrombus

Varices are abnormally dilated veins
The most common intraoral location is the ventral surface of the tongue
If the varix contains a thrombus, it presents as a firm bluish purple nodule that does not blanch on pressure

multiple bluish purple, irregular, soft elevations that blanch on pressure

Amalgam Tattoo and Other Foreign-Body Pigmentation

Amalgam tattoo is caused by the presence of metallic material in the oral tissues.

Amalgam tattoos are painless, gray-blue macules that range in size from a few millimeters to greater than 1 cm.

The gingiva and alveolar mucosa are the most common sites of involvement

No signs of inflammation are present at the periphery of the lesion



Accidental implantation of dental filling material into the gingival or buccal mucosa

Graphite accumulation

Melanotic Macules
The labial melanotic macule is a benign pigmented lesion
oral melanotic macule is the same lesion seen inside the oral cavity, most commonly on the gingiva, buccal mucosa and palate
Melanotic macules are usually smaller than 1 cm in diameter and show a well-demarcated smooth border
The colour may be light or dark brown and is homogeneous within each lesion.
They usually occur as single lesions

Labial melanotic macule.

Increased numbers of melanocytes along the junctional zone
Intraoral melanocytic nevus
Nevus cells located within the connective tissue


Pigmented Nevi



Junctional nevi are flat and dark brown in color because the nevus cells proliferate at the tips of the rete pegs close to the surface.


Intramucosal and compound nevi are typically light brown, dome-shaped lesions


Melanocytic nevi constitute benign neoplasms of cutaneous melanocytes


Proliferation of benign neoplastic melanocytes along the sub mucosal junction -=junctional nevus


Migration of these cells to the underlying mesenchyme tissue =compound nevus


Loss of the junctional component of the nevi, so that all remaining melanocytes are located within the sub epithelial connective tissue stroma = sub epithelial nevus
Pigmented Nevi


Blue nevus
A blue nevus is a benign, acquired melanocytic lesion that typically presents as an asymptomatic, blue-black smooth-surfaced macule or papule and usually measures less than 6 mm in diameter.

Two thirds of all intraoral blue nevi are found on the hard palate, and the buccal mucosa is the second most common site of presentation.

The common blue nevus, which is the most frequent subtype seen in the oral cavity is characterized by an Intramucosal proliferation of elongated, bipolar, spindle-shaped melanocytes.

Blue nevus on hard palate

Blue nevi are characterized by proliferation of dermal melanocytes within the deep connective tissue at some distance from the surface epithelium, which accounts for the blue color

Oral Melanoacanthoma

Oral melanoacanthoma is an uncommon benign pigmented lesion of the oral mucosa
characterized by proliferation of dendritic melanocytes scattered throughout the thickness of an acanthotic and hyperkeratotic surface epithelium
Clinically, the lesion appears flat or slightly raised and is hyper pigmented, the color ranging from dark brown to black.
The buccal mucosa and soft palate are the most common sites of occurrence.

Melanoacanthoma on the right buccal mucosa

Proliferation of benign dendritic melanocytes scattered throughout the epithelium.

Oral Melanoma

It is characterized by proliferation of malignant melanocytes along the junction between the epithelial and connective tissues, as well as within the connective tissue
The most common site is the palate, followed by the gingiva
oral melanoma may present as an asymptomatic, slow-growing brown or black patch with asymmetric and irregular borders or as a rapidly enlarging mass associated with ulceration, bleeding, pain and bone destruction








Histopathology of oral melanoma with atypical melanocytes, nuclear pleomorphism and hyperchromatism

They tend to be more aggressive than their cutaneous counterparts

Treatment involves radical surgical excision with clear margins
Radiation and chemotherapy are ineffective

SUMMARY