Animal-type melanoma

What is the animal type? melanoma?

Melanoma is a skin Cancer that arises from pigment cells (melanocytes)

Animal-type melanoma is a very rare form of melanoma with a dark brown / black appearance. The diagnosis is made from your histological appearance in biopsy. The name "animal type" arises from the close similarity with the pigmented melanocytic tumors found in gray horses. Also known as equine-type melanoma, pigment synthesis melanoma, and pigment pigment. epithelioid melanocytoma

Animal-type melanoma was first described by Darier in 1925.

Who gets animal-type melanoma?

Animal-type melanoma can occur at any age, even during childhood. Some studies have found that it is more common in young adults, but another reported that it is more common in middle-aged and older adults.

Males and females appear to be equally affected.

Patients with animal-type melanoma are no more likely than the general population to have well-known risk factors for common types of melanoma (such as fair skin, family history, and sun damage).

What does animal type melanoma look like?

Animal-type melanoma can develop anywhere in the body. It arises from normal skin (de novo), instead of a pre-existing nevus (Mole).

Animal-type melanoma usually presents as dark brown / back papule or nodule. At the time of diagnosis, it was likely present for a year or more.

In general, animal-type melanoma has the ABCDE criteria:

• Asymmetry
• Border irregularity
• Color variation
• Diameter more than 6 mm.

The clinic differential diagnosis includes blue naevus variants:

• Deep penetrating nevus
• Cellular blue nevus
• Evil one blue nevus
• Epithelioid blue nevus, which may be associated with the Carney complex, a family association of skin tumors with cardiac myxoma and psammomatous melanotic schwannoma. See myxoma syndromes.

What tests should be done?

After clinical evaluation has suggested a skin injury To suspect melanoma, the lesion should be examined with a dermatoscope. The dermoscopic appearance of animal-type melanoma may show an unstructured blue pattern, irregular whitish structures, and irregular, large blood vessels.

After the injury is removed by excision biopsy a histology The animal-type melanoma report may report:

• Strongly pigmented compound or dermal melanocytic tumor
• Epithelioid and spindle melanocytes.
• Malignant or soft cytological appearance
• Usually low mitotic activity and infrequent ulceration,
• There are no features to suggest regression.

the pathologist It can be difficult to make a definitive diagnosis of melanoma, since the characteristics of animal-type melanoma may resemble those of blue naevi. Therefore, there are equivocal and unequivocal cases.

What is the treatment for animal type melanoma?

Confirmed animal-type melanoma is widely removed, with a clinical margin depending on Breslow thickness.

Many centers offer sentinel lymph node biopsy if the melanoma has a Breslow thickness of 1 mm or more, or invader tumors that are less than 1 mm thick but have ulceration or a mitotic rate of 1 or more.

• In a review of 22 cases, Ludgate et al found that patients with equivocal animal-type melanoma were younger and sentinel lymph node biopsy tended to be negative, compared to those with unequivocal animal-type malignant melanoma.
• Antony et al reported that although animal-type melanoma has a regional tendency lymphatic spread, very unlikely to drive remotely metastasis and death

Staging

Staging melanoma means finding out if melanoma has spread from its original place on the skin. Most melanoma specialists refer to the American Joint Committee on Cancer (AJCC) cutaneous melanoma staging guidelines (2009). In essence, the stages are:

What happens at the follow-up?

The main goal of follow-up is to detect recurrences early, but it also offers the opportunity to diagnose a new primary melanoma at the earliest possible opportunity. A second invasive melanoma occurs in 5 to 10% of melanoma patients; An unrelated melanoma in situ affects more than 20% of melanoma patients.

The Australian and New Zealand Melanoma Management Guidelines (2008) make the following recommendations for the follow-up of patients with invasive melanoma.

• Self-examination of the skin
• Regular skin checks by the patient's preferred healthcare professional.
• Follow-up intervals are preferably half-yearly for five years for patients with stage 1 disease, quarterly or quarterly for five years for patients with stage 2 or 3 disease, and annually thereafter for all patients.
• Individual patient needs should be considered before offering adequate follow-up
• Provide education and support to help the patient adjust to his illness.

Follow-up appointments can be made by the patient's general practitioner or specialist or can be shared.

Follow-up appointments may include:

• A check from the scar where the primary melanoma was removed
• An idea of regional lymph nodes
• A general examination of the skin.
• A complete physical exam
• In those with many moles or atypical moles, base Whole body images and sequential macro and dermoscopic images of melanocytic lesions of interest (mole mapping)

In those with more advanced primary disease, follow-up may include:

• Blood tests, including LDH
• Images: ultrasoundX-rays Connecticut, Magnetic resonance me PET scan.

Tests are generally not worth it for patients with stage 1/2 melanoma unless there are signs or symptoms of the disease reappearance or metastasis. And tests are not considered necessary for healthy patients who have stayed well for 5 years or more after the removal of their melanoma, at any stage.

What is the prognosis for animal melanoma patients?

Since animal-type melanoma is rare, there is less information on forecast available compared to other types of melanoma. It is believed to have a better prognosis than superficially spreading malignant melanoma of a similar Breslow thickness.

• It can spread to regional lymph nodes and recur locally.
• Recurrences have been observed many years after presentation.
• Visceral Metastasis and death are extremely rare.
• Patients with equivocal animal-type melanoma have a lower risk of lymph node spread and death than those with unambiguous malignancy.