Melanoma is perhaps the most known type of skin cancer. Interestingly, it is the rarest but most deadly type. Only about 6% of all skin cancers are caused by melanoma. This small percent however results in about 80% of all skin cancer-related deaths.
The last several decades have seen a tremendous increase in the number of melanoma diagnoses according to melanoma statistics. This thought to be due to accumulative sun exposure, which plays a major role in development of lentigo maligna melanoma in adulthood.
Since melanoma develops in the cells that give color to the skin (melanocytes), it mostly appears as dark brown moles, spots or patches on the skin. This is however not always the case. There are several variations of melanoma, most of which are discussed in this article. More details can be found here what is melanoma cancer.
Red melanoma is of the amelanotic melanoma type. It occurs when affected melanocytes fail to produce melanin. About 70% of amelanotic melanomas are red in color and account for about 4% of all melanomas.
Melanomas of this type are often misdiagnosed or caught in later stages. Since the ABCDEs may not be very effective in identifying melanomas of this form, the 3Rs can be used instead.
The 3Rs stand for red, recent changes and raised. Red describes the common coloration that is present in melanoma tumors of this from. Ulcerated melanomas may also appear red. Recent changes describe any change in physical state of the tumor. Such changes may include shape, size, texture and coloration. Raised describes the tendency of malignant moles to be dome-shaped or elevated.
Red melanoma may also be a nodular melanoma. This is an aggressive type with very poor prognosis. Its main characteristic is appearance of a red lesion that rapidly gains mass.
It is very important that a moles, lesions or spots displaying suspicious signs of malignancy be checked by a doctor. A biopsy will be needed to confirm diagnosis and rule out other conditions such as eczema and basal cell carcinoma. After diagnosis, treatment can begin immediately.
Internal melanoma is often of the mucosal melanoma type. It can also be a complication of advanced cutaneous melanoma.
Mucosal melanoma is rare. It develops on mucosal body surfaces and cavities. Commonly affected body parts include oral cavity, nasal passages, anus and vagina.
Mucosal membranes contain small numbers of melanocytes. This means that melanoma can develop in these membranes too. The exact reason as to why the disease develops in these areas is still not known.
Internal melanoma can be hard to catch in its early stages. Signs and symptoms depend on the affected region. They may include;
- Oral cavity – white spot inside mouth, dentures falling out of place, presence of a lump
- Nasal passages – nasal blocks, lump inside nose, blood in mucus
- Vagina – vaginal discharge, pain during/after sex, bleeding, presence of a lump
- Anus – bleeding, presence of a lump, changes in bowel habits
Internal melanoma can also develop as a result of melanoma cells that have spread from a primary tumor. The most commonly affected organs are the lungs, brain, liver and abdominal organs. Signs and symptoms depend on malignant melanoma stages and the affected organ. They may include;
- Lungs – difficulty breathing, chronic cough, blood in cough
- Liver – reduced liver function, loss of weight, vomiting, nausea, lump in upper abdomen
- Brain – seizures, headaches, numbness in extremities
- Bones – frequent fractures, loss of bone density, pain in bones
- Lymph nodes – swelling of lymph nodes
White melanoma is very rare. It can be caused by mucosal melanoma in the oral cavity. Melanoma in mouth mostly shows up in gums and inside cheeks. Ill-fitting dentures are thought to be a major risk factor.
Most melanomas in mouth appear as spots rather than tumors. It for this reason may be hard to spot them. A common characteristic that may help with identification is tendency to ulcerate. If you notice a sore that doesn’t heal in the mouth, it is best that it gets checked by a doctor.
White melanoma can also be a result of a differently colored melanoma. It is common for melanomas to have more than one color. Black and brown are usually the primary colors. Secondary colors may include blue, orange, pink, grey and white.
Brown and Black melanoma
Most cutaneous melanomas are brown or black. As more melanocytes accumulate on affected skin areas, more pigment is present hence the brown or black appearance. The ABCDEs can be used to identify early signs of malignancy in black melanoma. The following types can pose as black melanoma;
Superficial spreading melanoma
It accounts for most cases of melanomas. This type is most common in middle aged adults. It tends to spread across the skin before becoming invasive. In most cases, it will start with an elevated growth with no regular borders.
Accumulative sun exposure is the main cause of this melanoma. It for this reason appears in later years of life. In most cases, it will start as a flat spot or slightly raised growth that is black or brown in color. The symptoms will show up in areas that are usually exposed to the sun.
Acral lentiginous melanoma
This type affects hands and feet. Most cases of this melanoma are reported in colored people. It for this reason is not associated with UV radiation. Black or brown spots or patches of skin discoloration are usually the first signs. Most people tend to ignore such signs, mistaking them for blood blisters or skin lesions. The main unique feature is that blood blisters and other blemishes usually fade away and disappear before long. A subtype of this melanoma that develops under nails is known as subungual melanoma. It mostly occurs in the big toe and thumb although any nail can be affected. A vertical streak that runs from the cuticle to the tip of the nail is the main early sign. With time, discoloration will spread to the nail bed. On subungual melanoma pictures, the streak may appear on the nail matrix or in the nail bed. Melanoma under toenail sometimes requires that part of the affected toe be amputated.
Pink melanoma is another variation of amelanotic melanoma. It is very hard to detect and thus has poor prognosis. The variation accounts for about 5% of all melanomas.
The same trick mentioned as potentially helpful in identifying red melanoma can also help in this case. First, be on the lookout for recent changes in a spot, lesion or skin growth that has recently showed up. From there, start looking for signs of malignancy such as elevation, ulceration and itchiness.
Stage 2 melanoma is the last of the safest melanoma stages. Once tumors are past this stage, they reach lymphatic vessels and blood vessels. It will be only a matter of time before several malignant cells break free and spread. The good thing is that most melanomas will have exhibited a number of noticeable signs before advancing beyond this stage.
Note that some melanomas can take a while before exhibiting noticeable melanoma signs. It is therefore very important to closely monitor lesions or spots that weren’t there sometimes back.
Small melanoma may also be what is commonly referred to in situ melanoma. In simple terms, these are tumors that are confined to the epidermis. Epidermis is the upper layer of the skin. Melanocytes are contained in this layer. Tumors confined to the epidermis are the easiest to treat.
The only way to know if a melanoma is small or not is by going for medical diagnosis. Melanomas are measured in thickness. Breslow thickness and Clark level are commonly used to describe the thickness of a melanoma.
- Breslow thickness – it describes the measurement of a melanoma from the granular layer to the bottommost part of the tumor. The measurement is given in mm. small melanomas or stage 0 tumors are less than 1mm in thickness. Large ones are larger than 6mm.
- Clark level – this method uses 5 levels to describe the anatomical invasion of a tumor. Small tumors are yet to leave the epidermis while large ones have reached the subcutaneous layer.
A small melanoma is removed with excision surgery. This is after a margin has been set with the help of imaging tests. Melanoma in situ excisional margins are usually 5mm but can be as large as 2cm for large tumors. 9mm margins have a higher success rate compared to 5mm margins. Other metastatic melanoma treatment such as chemotherapy and immunotherapy are usually necessary when dealing with large tumors.
While most melanomas form lesions, moles or start in existing moles, some begin as spots on skin. Such can be particularly dangerous. A good example is the melanoma that develops in feet and hands.
But whether a melanoma begins as a spot or a growth, it will keep spreading across the skin or gaining mass in a short timeline.