OVERVIEW

What are congenital melanotic macules of the tongue?

Congenital melanotic macules of the tongue (CMMT) is a relatively rare benign condition first reported in medical literature in 2003.

Individuals with this condition have single or multiple pigmented spots (usually multiple) on the tongue present at birth, which do not cause discomfort or other symptoms.

The condition rarely becomes malignant and does not affect normal life, so treatment is unnecessary. Regular follow-ups as advised by a doctor are sufficient.

Are congenital melanotic macules of the tongue common?

They are rare, with few cases reported in literature. However, since the condition is asymptomatic from birth and does not interfere with daily life, some individuals may not seek medical attention, meaning the actual number of cases may be higher than reported.

Are congenital melanotic macules of the tongue the same as black hairy tongue?

No.

Black hairy tongue, also known as hairy tongue, is characterized by elongated filiform papillae on the tongue surface, several millimeters in length, appearing gray-brown or black. It not only affects appearance but may also cause discomfort while eating, leading to significant psychological distress for patients.

Typically, black hairy tongue occurs on the central dorsum of the tongue, with darker pigmentation toward the center. The lesions may gradually expand but can fade, desquamate, and disappear completely within weeks to months, leaving no traces.

In contrast, congenital melanotic macules are present at birth, asymptomatic, and the dark patches only enlarge proportionally with body growth without disappearing on their own.

SYMPTOMS

What are the manifestations of congenital lingual melanotic macules?

• The pigmented macules may be single or multiple.
• The macules can be located on the sides or the midline of the tongue.
• The diameter of the macules ranges from 3 mm to 3 cm, increasing proportionally with the child's growth, maintaining a consistent size-to-tongue surface area ratio.
• The color of the macules may be uniform or uneven, appearing as ring-shaped, brown spots.
• Patients usually have no history of bleeding, ulceration, or trauma, nor a family history of the condition.
• The macules typically persist throughout the patient's lifetime and rarely undergo malignant transformation.

CAUSES

What is the cause of congenital lingual melanotic macules?

The cause is unknown. No association has been found with maternal conditions during pregnancy.

Are congenital lingual melanotic macules hereditary?

No hereditary tendency has been identified so far.

DIAGNOSIS

How is congenital lingual melanotic macule diagnosed?

For infants with asymptomatic, no lymphadenopathy, and no family history of systemic diseases related to mucosal pigmentation, the presence of a melanotic macule on the tongue at birth without abnormal discomfort can be preliminarily confirmed as congenital lingual melanotic macule.

If the infant exhibits crying or discomfort due to other concurrent conditions, making the diagnosis uncertain, a biopsy of the affected tongue area may be required for definitive diagnosis.

The characteristic histological features of congenital lingual melanotic macule include: increased melanin deposition in the basal cell layer, a normal number of melanocytes, scattered subepidermal pigment-laden macrophages, and varying degrees of hyperkeratosis.

What precautions should be taken for a tongue biopsy in congenital lingual melanotic macule?

• Due to the newborn's poor cooperation, the biopsy procedure may be more challenging and may require anesthesia. Parents should understand and cooperate.
• Since newborns have weak immunity and are prone to infection, oral hygiene must be maintained before the biopsy. Postoperatively, the wound should be closely monitored and kept clean. Avoid excessive sucking by the infant to prevent infection and more severe complications.

What conditions should congenital lingual melanotic macule be differentiated from?

Congenital lingual melanotic macule should be distinguished from other conditions or diseases causing oral mucosal pigmentation, such as pigmented fungiform papillae, black hairy tongue, Laugier-Hunziker syndrome, Peutz-Jeghers syndrome, pigmented nevi, and malignant melanoma.

Among these, congenital lingual melanotic macule is the only condition present at birth. Other diseases have different etiologies or develop later due to unknown causes, leading to tongue pigmentation.

TREATMENT

Which department should I visit for congenital tongue melanotic macules?

Department of Stomatology or Oral Mucosal Diseases.

Does congenital tongue melanotic macule require treatment?

No treatment is usually necessary if the diagnosis is confirmed.

Is follow-up required for congenital tongue melanotic macule?

Yes.

Congenital tongue melanotic macule is a benign lesion and generally does not require specific treatment, including biopsy, which should also be avoided if possible.

However, after diagnosis, regular follow-up is necessary. If significant changes occur during follow-up, a tongue biopsy should be performed to rule out malignant transformation, such as congenital melanocytic nevus. In all current literature reports, only two cases of oral congenital melanotic macules have progressed to melanoma. If malignancy is confirmed by biopsy, prompt surgical or other treatments are required.

DIET & LIFESTYLE

What should patients with congenital lingual melanotic macules pay attention to in their diet?

• For newborns, breastfeeding or formula feeding is the primary method, so it is only necessary to maintain food hygiene and avoid oral trauma.
• For those who have started eating normally, a healthy, regular, and balanced diet is recommended, with more vitamin-rich foods and minimal consumption of spicy or irritating foods.

What should patients with congenital lingual melanotic macules pay attention to in daily life?

• Both adult and minor patients should avoid trauma and infection at the affected site.
• Patients with psychological concerns about the special color of their tongue may require psychological counseling to alleviate cancer-related fears.
• Maintain oral hygiene, and those with dentures should keep them clean.
• Schedule regular follow-up examinations to prevent malignant transformation.

PREVENTION

Can congenital tongue melanotic macules be prevented?

Since congenital tongue melanotic macules is a disease with unknown etiology, it cannot currently be prevented.