Melanoma
Melanoma is one of the most common cancers, especially among people in Western countries. Melanoma occurs when pigment cells called melanocytes become malignant.
Melanocytes are found throughout the lower part of the epidermis. They produce melanin, the pigment that gives skin its natural color. When skin is exposed to the sun, melanocytes produce more pigment, causing the skin to tan, or darken.
These pigment cells are mostly present in the skin. When melanoma starts in the skin, the disease is called cutaneous melanoma. It is the most serious type of skin cancer.
Melanoma may also occur in other parts of the body. When it occurs in the eye, it is called ocular melanoma or intraocular melanoma. In rare cases, it also occurs in the meninges, the digestive tract, lymph nodes, or other areas where melanocytes are found. But in most cases Melanoma arises in the skin.
Though this disease affects people of all ages, the chance of developing it increases with age. In men, melanoma is often found on the area between the shoulders and the hips, or the head and neck. In women, it often develops on the lower legs. Melanoma is rare in black people and others with dark skin. When it does develop in dark-skinned people, it usually occurs under the fingernails or toenails, or on the palms or soles.
Groups of lymph nodes are found throughout the body. These lymph nodes trap bacteria, cancer cells or other harmful substances that may be in the lymphatic system. As melanoma spreads, cancer cells may show up in nearby lymph nodes. When this happens, cancer cells spread to other parts of the body such as the liver, lungs, or brain, through the lymphatic fluid. In such cases, the cancer cells in the new tumor are still melanoma cells, and the disease is called metastatic melanoma, not liver, lung, or brain cancer.
Causes
The exact causes of melanoma are yet to be determined. However, there are certain factors that play a role in increasing a person's chance of developing melanoma:
Numerous moles (more than 50):
A number of even ordinary moles can increase the probability of developing melanoma.
Dysplastic nevi:
These are abnormal moles. Though dysplastic nevi are common, they are more likely than ordinary moles to become cancerous. And people with a large number of dysplastic nevi are at greater risk of developing melanoma. The risk is especially high for people with a family history of both dysplastic nevi and melanoma.
Fair skin:
People with fair skin, who get freckled or sun burnt easily, are more likely to develop melanoma than those with dark skin. This is probably because light skin is more easily damaged by the sun. This condition is also more prevalent in people who have red or blond hair and blue eyes.
Personal history of melanoma or skin cancer:
Melanoma can recur. People who have been treated for melanoma have a high risk of a second melanoma. Some people develop more than two melanomas. People who had other skin cancers such as basal cell carcinoma or squamous cell carcinoma are also at increased risk of developing melanoma.
Family history of melanoma:
Melanoma can be genetic. If close relatives develop melanoma, it increases the person's chance of developing this disease. In fact, when a person is diagnosed with melanoma, the family members should also be checked for melanoma. About 10 percent of all patients with melanoma have a family member with this disease.
Weakened immune system:
When diseases like cancers or HIV, and the drugs used to treat these diseases, weaken a person's immune system, there is an increased risk of developing melanoma.
Severe, blistering sunburns:
People who have had a severe case of sunburn are at increased risk, even if it had occurred during childhood or adolescence. Sunburns in adulthood are also a risk factor for melanoma.
Ultraviolet (UV) radiation:
Exposure to UV radiation from natural as well as artificial sources can increase the chance of melanoma. UV radiation from the sun causes premature aging of the skin and skin damage that can lead to melanoma. This is why this disease is more common in people who live in places that get large amounts of UV radiation from the sun. Artificial sources of UV radiation, such as sunlamps and tanning booths, can also cause skin damage and increase the risk of melanoma.
Signs & Symptoms
The characteristics such the size, shape, or color of moles on one's body can indicate melanoma:
Irregular edges or borders
More than one color
Asymmetrical (if the mole is divided in half, the 2 halves are different in size or shape)
Itchiness
Oozing, bleeding, or ulceration
Change in pigmentation
Satellite moles, which are new moles that grow near an existing mole
Self-Exam
The ideal time to do a skin self-exam is after a shower or bath. Check your skin in a well-lit room using a full-length mirror and a hand-held mirror. It's important to be familiar with your birthmarks, moles and blemishes and how they look and feel like.
Check for anything unusual from head to toe, including the back, the scalp, between the buttocks, the genital area, the toenails, the soles and the spaces between the toes:
A new mole that looks abnormal
A change in the size, shape, color, or texture of an existing mole
A sore that does not heal
A black or blue-black area
Newly formed fine scales and itching in a mole
A comb or a blow dryer could help move your hair, enabling you to see clearly. Alternatively, you could also have a relative or friend check through your hair because this is difficult to do yourself.
Melanomas can vary greatly in appearance. They usually do not cause any pain.
Diagnosis
A biopsy is the only way to make a definite diagnosis of melanoma. If the suspicious-looking growth being examined is entirely removed, it is called an excisional biopsy. But if the growth is too large to be removed entirely, only a sample of the tissue is removed. In any case, a growth that is suspected to be cancerous is never shaved off or cauterized.
A biopsy is usually done using local anesthesia. The tissue is then examined to check for cancer cells. And if the diagnosis is melanoma, the extent or stage, of the disease is determined before planning treatment.
There are few other tests, which are conducted to ascertain how deeply the melanoma has invaded the skin, and whether melanoma cells have spread to nearby lymph nodes or other parts of the body:
X-ray
CT scan
MRI
PET (positron emission tomography) scan
Laboratory tests of tissue, blood, urine or other bodily substance
Lymphadenectomy, where the lymph nodes are removed and examined to see whether they contain cancer
Accurate staging of the disease helps plan treatment and monitor the condition over time:
Stage 0: In stage 0, the melanoma cells are found only in the epidermis, the outer layer of skin cells, and have not invaded deeper tissues. This stage is also called melanoma in situ.
Stage I-a: Here, the tumor is no more than 1 millimeter (1/25 inch) thick. The outer layer of skin may appear scraped, which is called an ulceration.
Stage I-b: This is when the tumor is between 1 and 2 millimeters (1/12 inch) thick. And the melanoma cells have not spread to nearby lymph nodes. Here again, there is no ulceration.
Stage II-a: The stage is similar to the previous one with the tumor between 1 and 2 millimeters thick, and no ulceration found.
Stage II-b: Here, the thickness of the tumor is more than 2 millimeters and there may be ulceration. With the melanoma cells still not spread to nearby lymph nodes.
Stage III: In this stage, the tumor may be of any thickness, with or without ulceration. With the melanoma cells spread to one or more nearby lymph nodes; or have spread to tissues just outside the original tumor but not to any lymph nodes.
Stage IV: In the final stage, the melanoma cells are detected in other organs, apart from lymph nodes and skin areas far away from the original tumor.
Recurrent: This is when the disease comes back after it has been treated. It may recur in the original site or in another part of the body, such as the lungs or the liver.
Prevention
Precautionary steps can be taken to help avoid or reduce the risk of melanoma caused by UV radiation:
Avoid exposure to the midday sun (from 10 a.m. to 4 p.m.) whenever possible. A simple way to gauge exposure risk is to see if your shadow is shorter than you are. If so, then remember to protect yourself from the sun.
When outdoors, wear long sleeves, long pants and a hat with a wide brim to prevent direct exposure. Wear sunglasses that have UV-absorbing lenses that block at least 99 percent of UVA and UVB radiation. Sunglasses can protect both the eyes and the skin around the eyes.
Take care to shield yourself from UV radiation that can penetrate light clothing, windshields, and windows; also from UV radiation reflected by sand, water, snow and ice. Use sunscreens with a high sun protection factor (SPF). Those lotions, creams, or gels that contain SPF of 30 or higher provide the most protection against sunburn.
Treatment
Treatment for melanoma is planned with a team of specialists, which may include a dermatologist, a surgeon, a medical oncologist, a radiation oncologist and a plastic surgeon. A combination of different methods of treatment is used depending on the extent of the disease, the patient's age as well as general health and other factors.
Treatment may involve surgery, chemotherapy, biological therapy, or radiation therapy.
At any stage, patients may be treated to control pain and other symptoms of the cancer, to relieve the side effects of therapy, and to ease emotional and practical problems. This kind of treatment factors in symptom management, supportive care and palliative care.
Treatments used for each stage can vary according to a patient's preference and prognosis:
Stage 0
Minor surgery may be required to remove the tumor and some of the surrounding tissue.
Stage I
Surgery is used not only to remove the tumor, but it may also be necessary to remove as much as 2 centimeters (3/4 inches) of tissue around the tumor. To cover the wound, the patient may have skin grafting.
Stage II or Stage III
Again surgical removal of the tumor is mandatory. It may also be necessary to remove nearby lymph nodes and as much as 3 centimeters (1 1/4 inches) of nearby tissue. Skin grafting may be done to cover the wound.
Stage IV
Palliative care is often required here. Which may include radiation therapy, biological therapy, or chemotherapy to relieve symptoms. This are for helping the patient feel better physically and emotionally. This type of treatment is also intended to control pain and other symptoms and relieve the side effects such as nausea that occur due to certain therapies.
Though the treatment helps boost the immune system to fight the cancer cells, it does little to aid in prolonging the life of the patient at this stage.
Surgery may also be recommended to remove lymph nodes that contain cancer cells or to remove tumors that have spread to other areas of the body.
Recurrent Melanoma
Treatment for recurrent melanoma depends on factors such as the location where the cancer has recurred and methods of treatment used previously.
As with Stage IV melanoma, treatment cannot be aimed at curing the disease. Here again, palliative care, often becomes an important part of the treatment plan.
A combination of radiation therapy, biological therapy, chemotherapy is used to ease symptoms while patients are getting anticancer treatments to slow the progress of the disease. In certain cases, heated chemotherapy drugs are injected directly into the tumor.
For some, palliative care is advised only to improve their quality of life by easing pain and controlling nausea and other symptoms. Surgery may also be used to remove the tumor.
Nutrition and Follow-up Care
Nutrition
Patients undergoing treatment for melanoma may have poor appetite, due to fatigue and discomfort caused by symptoms such as nausea, or vomiting. Their taste buds might also not function effectively.
However, it%u2019s important for patients to eat well during cancer therapy, as they need enough calories to maintain a good weight and protein to build strength. A good nutritious diet also helps patients feel better and have more energy.
Follow-up Care
Patients face a high risk of developing new melanomas or a recurrence of the original melanoma in nearby skin or in other parts of the body. For an early diagnosis of a new or recurrent melanoma, patients should diligently follow the schedule for regular checkups.
Especially patients with dysplastic nevi and a family history of melanoma should have frequent checkups. A monthly self-test for abnormal growth is also impotant. The chance of recurrence is greater for patients whose melanoma was thick or had spread to nearby tissue than for patients who have had very thin melanomas. Follow-up care for those who have a high risk of recurrence may include x-rays, blood tests, and scans of the chest, liver, bones, and brain.
Risks
Treatment for melanoma may damage healthy cells and tissues, causing adverse side effects. These side effects depend on many factors, including the location of the tumor and the method and extent of the treatment. And the effects may not be the same for each person. In fact, they may even change from one treatment session to the next.
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