Melanoma

Serious skin cancer, which may be superficial or invasive
Caused by a proliferation of melanocytes, and may be caused by various factors, including sun damage to skin and heredity
Initially presents as a newly formed mole or freckle or one which has changed in appearance, or grows quickly

Melanoma is a serious cancerous condition, which may be superficial or invasive. The condition initially presents as a newly formed or recently changed mole or freckle. Lesions may change color, shape and size, and may be accompanied by inflammation, discharge, and changes to sensation in the area. To be classified as a melanoma, lesions must possess the following traits: A: asymmetry, B: irregular borders, C: variable coloring, D: size (diameter over 6mm), and E: evolution (growing, changing in shape or texture). Some doctors add F: for funny looking mole (ugly duckling mole or soldier marching out of step).Lesions typically grow quickly, and usually affect the back in men, and the legs in women. Lesions may also appear in mucosal surfaces such as the lips, genitals, or eyes, and in rare cases the brain.

Melanomas are further classified by type, typically based on their development and progression. Types which develop as flat patches (horizontal growth phase) include superficial spreading melanoma, lentigo maligna melanoma, acral lentiginous melanoma. These types tend to grow slowly and may be accompanied by thickening or the development of a nodule in the affected area, indicating entry into the vertical growth phase. Types which indicate involvement of deep tissue include nodular melanoma (consists of a quickly growing nodule), mucosal melanoma, and desmoplastic Melanoma (fibrous tumors which form on the nerves). Differing types may develop in conjunction with each other.

Melanomas form because of proliferation of melanocytes (pigment producing cells in the skin). This excess production may be due to various factors, including sun damage, heredity, large numbers of moles, atypical moles, and previous melanoma. Those persons with fair skin, or who experience excessive sun exposure or damaging sunburns are more likely to develop the condition. Additionally, invasive melanoma may metastasize and spread to internal organs through the lymphatic system once it penetrates the lower layers of skin.

Differential Diagnosis (Other conditions with similar appearance)
Basal cell carcinoma
Lentigo Maligna Melanoma
Mycosis fungoides
Benign melanocytic lesions
Dysplastic nevus
Squamous cell carcinoma
Metastatic tumors to the skin
Blue nevus
Epithelioid (Spitz) tumor
Pigmented spindle cell tumor
Halo nevus
Atypical fibroxanthoma
Pigmented actinic keratosis
Sebaceous carcinoma
Histiocytoid Hemangioma

Diagnosis
Key Points
Initial diagnosis based on appearance of the affected area
Dermoscopy and/or skin biopsy will be performed to confirm diagnosis and rule out other conditions
Invasive melanomas may require imaging tests to determine the extent of involvement

Melanomas are initially diagnosed based on the appearance of the lesion. A dermoscopy or biopsy of the lesion will confirm the diagnosis and rule out other conditions. In the case of invasive melanomas, imaging tests may be performed to determine the extent of lesion involvement.

Treatment
Treatment typically consists of removal of lesions
Invasive or widespread lesions may require more aggressive treatment
*Recurrence is a possibility, so regular examinations of skin are important

Treatment of melanomas usually consists of removal via surgical excision, typically removing the lesion and a small part of the healthy skin surrounding it to ensure full removal of cancerous cells. In larger and/or thicker lesions, skin grafts and lymph node removal may be necessary. Invasive and/or widespread lesions may require more aggressive cancer treatments, but may not always resolve completely. Regular skin examinations are important after treatment to detect the presence of further lesions.