Facts about melanoma you should know
Lesions on various skin places used to be a sign of beauty. But until they are benign. As known about 50% of melanoma evolutes from benign lesions(congestion of melanocytes), other appear from unnatural growth of melanocyte cells. So both cases are based on melanocytes where they have invaded an epidermal and dermal layers of skin. There are normally about 10 to 40 lesions on human body. Some of them are native, inborn, some of them appear during 35 – 40 years. Later some of them may disappear.
Melanoma is not only a skin disease as it can also appear in eyes, respiratory system, even on cortex of brain. But most of cases (~90%) appears on skin.
As mentioned earlier it is hard to detect melanoma in early stages as it may appear as benign lesion. So if there is even a little suspicion about malignant lesions, it is necessary to attend screening at dermatologic specialist who usually photographs suspicious lesions and then analyses according to ABCD rule. Other non skin cases are even harder to detect. For instance if melanoma appears in lungs patient may have difficulties in breathing – like astma. Melanoma in bones may appear as bone ake.
Skin melanomas may be classified as follows:
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Radial melanoma (about 70% of skin melanoma cases) – appears from displastic lesions. Melanoma progress takes up to 5 years. Can be detected by using ABCD rule. More specific for elder ages. In early phases melanomas spreads in upper layer of skin – epidermis. Later it enters vertical growth phase after then cancer becomes dangerous as it starts to invade inner tissues;
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Nodular melanoma (about 15% of cases) – This type of melanoma rises very rapidly and is the most aggressive type of skin cancer. From the beginning this type of melanoma grows vertically up and down. So there is a danger from the beginning that melanoma will spread in to inner tissues. This type of melanoma appears to be dark black, blue, grey or red with smooth borders.
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Lentigoous maligna melanoma – appears usually in head and neck area bigger than 3 centimeters non symmetrical lesion. It takes long time to progress – up to 20 years. Most cases at 70 years old.
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Acral lentigous melanoma – more common for dar skinned people. It appears on palms of hands and foots – especially under nail of first finger. It takes short time to progress from 3 to 36 moths. Most common among 60 year age.
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Unclassified – other up to 5% of cases.
Generally speaking all melanomas growths in two phases: horizontal-radial and vertical. In radial phase lesion spreads in epidermis and papillary dermis without metastases. In this period patient can be easily cured. When growth enters vertical phase lesions spreads in to deeper tissues through dermis and deeper layers of skin. There begins metastases. In meny cases both phases come together. Most common metastases of melanoma are: in Dermis(50 -75%), Lungs(07 – 87%), Liver(54-77%), Brain(36 – 54%), Bones(23 – 49%), Digestive system(26 – 58%), Kidney(35 – 48%), Heart(40 – 45%).
How metastases are related to lesion size.
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<0.75mm – regional metastases(2-3%), far metastases(2-3%);
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0.76-1.5mm – regional metastases(25%), far metastases(8%);
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1.51-4mm – regional metastases(57%), far metastases(15%);
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>4mm – regional metastases(62%), far metastases(72%);
One of most important criteria is a number of metastases in lymphatic system. Depending on number of metastasis there is a statistics on survival from melanoma.
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No metastases in lymph – 73% to survive 5 years;
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1 - 3 metastases in lymph - 55% to live 5 more years;
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4 metastases in lymph - 26% to live 5 more years;
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macro metastases - 21% to life 5 more years and 12% to live 10 more years.
So number of metastases is proportional to survival.
When you should pay more attention to you skin lesions.
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Elder age people have to pay more attention as during age melanoma prognosis become more critical;
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Gender – man have more chances to get spreaded melanoma;
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Number of lesions on body – if there are more than average number of lesions on body;
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Skin color – white skinned people tend to have melanoma more offen than dark skinned people.
Main and only effective cure for melanoma stil is surgery when it is removed. But it is effective if there is no metastases. Otherwise complex treatment is taken without big chances. So it is important to diagnose melanoma in early stages before it has spreaded to other tissues.
References:
http://www.dermatologychannel.net/skincancer/melanoma/types.shtml
