Melanoma Skin Cancer
Melanoma Skin Cancer
The skin in the largest organ in the human body. It is a protective shield that envelops the body and protects the delicate internal organs from the harshness of the outer world.
Layers of the Skin
Skin has three distinct layers:
- Epidermis:It is the outermost thin layer of skin that provides a waterproof barrier. It is mainly responsible for generating new skin cells, imparting skin colour and protecting the body. Melanin the colouring pigment is present in this layer.
- Dermis: It is situated beneath the epidermis. This layer contains tough connective tissues, hair follicles, and sweat glands. Its primary functions are sweat secretion, imparting sensation, hair growth, secreting sebum and bringing blood to the skin.
- Hypodermis: It is the innermost subcutaneous tissue made of fat and connective tissue. Hypodermis is responsible for attaching the dermis to muscles and bones, assisting the blood vessels and nerve cells, regulating body temperature and storing fats.
The skin is entrusted with three major functions: protection, regulation and sensation.
- The primary duty of the skin is to provide protection and shield the body from mechanical impacts and pressure, variations in temperature, micro-organisms, radiation and chemicals.
- Skin plays an important role in regulating body temperature. The sweat glands activate to cool the body down and blood vessels in the skin tighten to prevent heat loss.
- Skin is one of the five sensory organs in the human body. It has an extensive network of nerve cells that detect and relay changes in the environment. It has more than five different receptors that respond to touch, and pain. Damage to these nerve cells results in a loss of sensation in the affected areas.
Cancer occurs when normal healthy cells undergo a genetic transformation and continue to multiply rapidly without any control. Most of the times, this result in the accumulation of unhealthy cells forming a hard mass called tumor.
This tumor may be benign (non-cancerous) or malignant (cancerous) in nature. The benign tumors are less dangerous and its spread is restricted to the site of origin only, while the malignant tumors are deadly and gradually navigates to different parts of the body.
Skin cancer is caused by DNA damage in the cells of the skin. This DNA transformation triggers mutations and results in the cells multiplying uncontrollably and forming malignant tumors. These cancer cells can invade the neighbouring cells and navigate to distant organs. Skin cancer is the most common type of cancer in US and most of the western countries.
There are three major types of skin cancers:
- Basal cell carcinoma (BCC),
- Squamous cell carcinoma(SCC),
Melanoma Skin Cancer
Melanoma is rare but the most dangerous form of skin cancer. In Melanoma Skin Cancer, the cancer cells originate in the pigment-producing melanocytes that are located in the epidermis.
Also known as malignant melanoma and cutaneous melanoma, some mutated melanoma cells can still make melanin, so most of the melanoma tumors are brown or black in colour and appears like a mole on the skin. In some rare cases, they do not make melanin and the tumor appears to be skin-coloured, pink, red, purple, blue or white.
Melanoma can form anywhere in the skin, they are most likely to be found on the chest, back, legs, neck and face. However, in some rare cases, they may also form in other parts of the body including the eyes, mouth, genitals, and anal area.
Types of melanoma
The main types of melanoma are as follows:
- Superficial spreading melanoma: This is the most common type of melanoma cancer accounting for about 70% of all cases of melanoma. It mostly occurs in the legs of women and the backs of men and is more prone to people in the age range of 30-50 years. These melanomas are mostly flat and have a variety of colours. It is easy to detect at an early stage and can be removed easily in case of correct diagnosis.
- Nodular melanoma: It accounts for about 20% of melanomas. It begins as deeper, blue-black to purplish lumps. They are more aggressive and may evolve faster. Untreated superficial spreading melanomas may become nodular and invasive at later stages.
- Lentigo maligna: It mainly occurs in places which are mostly exposed to the sun. Lentigo maligna looks like a large, irregularly shaped skin infection. It develops at a slow pace and may take many years to evolve into a more dangerous melanoma or may never turn out to be invasive. But owing to its unpredictability, it is usually recommended to remove through surgery.
Occurrence Rate of Melanoma Skin Cancer in India
The occurrence rate of Melanoma Skin Cancer in India is comparatively low mostly because of high melanin in the skin but it is the most lethal among all types of skin cancer. Owing to the advancement in treatment facilities and increasing awareness about cancer the annual mortality rate from malignant skin melanoma in India has seen a considerable declination. Statistically, 7.8 deaths/100,000 in men and 3.6% for women per 100000 in 2003 the overall mortality due to melanoma has decreased considerably.
Melanoma skin cancer can develop anywhere in the body but are more prone in areas that are constantly exposed to the sun’s radiation. In most of the cases, the very prominent sign of melanoma skin cancer is either the development of a new mole or change in an existing mole. However, not all moles assure the presence of cancerous cells neither it is the only symptom of melanoma cancer.
Cancerous moles vary greatly in appearance. While some may appear as a normal mole some give a clear hint. Here are ABCDE signs that help in identifying a cancerous mole.
A - Asymmetry
Cancerous moles appear in irregular asymmetric shapes where the two sides look very different from each other.
A benign or normal mole has smooth, even borders, whereas in case of melanoma the moles have irregular, notched or scalloped borders.
Most benign moles are either brown or black in colour. Having a variety of colors is another warning signal. A melanoma may have different shades of colours including red, pink, white or blue.
Benign moles are generally small. Melanomas are usually larger in diameter generally over ¼ inches. However, at the initial stages they may be smaller.
Normal moles neither grow nor change their shape, they appear same even after years. If a mole starts to evolve or change in size, shape, color, elevation, or another trait, or any new symptom such as bleeding, itching or crusting it might be a malignant melanoma.
Symptoms of hidden melanomas
- Acral-lentiginous melanoma is a very rare form of melanoma that occurs under a fingernail or toenail. It can also be found on the palms of the hands or the soles of the feet.
- Mucosal melanoma develops in the mucous membrane that lines the nose, mouth, esophagus, anus, urinary tract and vagina. Mucosal melanomas are very hard to detect as they resemble many common conditions.
- Ocular melanoma, found in the uvea i.e. the layer beneath the white of the eye. An eye melanoma may cause vision changes and is generally diagnosed during an eye exam.
The exact cause of all melanomas isn't known to date. Multiple studies have revealed that melanoma cancer occurs when the melanin-producing cells called melanocytes gets mutated due to damage in its DNA. However what causes this damage in the DNA is not known to precision.
A number of factors including environmental and genetic factors may contribute to forming melanoma cancer. Another potent factor that might lead to melanoma is exposure to ultraviolet radiation from the sun and from tanning lamps and beds is the leading cause of melanoma.
Risk factors encompass those activities or incidences which increase the chance of getting melanoma cancer. Some of the potential risk factors for melanoma cancer include:
- Exposure to harmful rays: It is the most common risk factor for melanoma cancer. Use of tanning booths, beds or high exposure to sun’s ultraviolet radiation or even X-ray radiations is harmful for the skin.
- Chemical Exposure: Contact with certain chemicals, such as arsenic and hydrocarbons in tar, oils, and soot possesses a threat to the skin.
- Fair skin: Fair skin is due to the lack of melanin pigment in the skin. Melanin protects the skin from UV radiation, in absence of it the skin is prone to sunburn. However, melanoma can develop in darker complexions.
- Multiple moles: Having many moles in the body increases the risk of Melanoma cancer. Also, having an unusual type of mole increases the risk of melanoma.
- Familial history: Having a track record of melanoma in the immediate family member increases the risk of this cancer.
- Age: Aging increases the risk of developing melanoma cancer, especially in women.
- Genrtic disorder: Certain genetic disorders that deplete skin pigment, such as albinism and xeroderma pigmentosum increases the risk of Melanoma cancer
Since most of the risk factors of melanoma cancer are controllable, certain conscious decisions help in preventing the fatal disease.
- Avoiding the sun during the middle of the day.
- Reducing sun exposure
- Wearing sunscreen and protective clothing all year round.
- Avoiding tanning lamps and beds.
- Focusing on your skin’s health
- Keeping an eye on your moles
- Regular screening of high risk individuals
Once cancer is diagnosed, it is assigned a stage based on the spread and severity of the cancer cells. Staging is a very crucial part as it is based on the stage that the complete treatment is planned and a probable outcome is analysed. Staging also gives an idea of the survival chances and outlook of the disease.
Melanoma skin cancer is categorized into 5 stages starting from 0 to 4, 0 being the nascent stage and 4 is the final or terminal stage. Here is a detailed look at the stages of melanoma skin cancer.
- Stage 0: Also known as melanoma in situ, the cancerous cells at this stage are found only in the epidermis. It has not spread to nearby lymph nodes or distant sites. This stage is.
- Stage I: The cancerous cells are still restricted to the skin and their size is no more than 2 mm thick. Depending on the thickness, the mitotic rate, and state of ulceration this stage is further categorized into two subgroups.
- Stage II: At this stage the melanoma has grown thicker and has penetrated through the epidermis into the dermis. The thickness ranges between 1.01mm to 4.0 mm. Depending on the thickness and state of ulceration this stage can be further divided into 3 subgroups.
- Stage III: At this stage, melanoma has spread through the lymphatic system, either to a regional lymph node or to a skin site on the way to a lymph node, called “in-transit metastasis.” Depending on the size and number of lymph node involved and the state of ulceration this stage is further categorized into three subgroups.
- Stage IIIA: The cancer size is less than 2.0 mm thick and has spread to 3 or less lymph nodes. It has not spread to distant sites and the cancer may or may not be ulcerated.
- Stage IIIB: The cancer size is less than 4.0 mm thick and has spread to one or more lymph node(s) and has spread to nearby skin or to skin lymphatic channels around the tumor. It has not spread to distant sites and the cancer may or may not be ulcerated.
- Stage IIIC: The cancer size is less than 4.0 mm thick and the cancerous cells have spread to one or more lymph nodes or to very small areas of nearby skin or to skin lymphatic channels around the tumor. It has not spread to distant sites.
- Stage IIID: The cancer size is thicker than 4.0 mm and is ulcerated. The cancerous cells have spread to 4 or more lymph nodes or have spread to very small areas of nearby skin or to skin lymphatic channels around the tumor. It has not spread to distant sites.
- Stage IV: At this stage, melanoma has spread to other parts of the body, such as distant locations on the skin or soft tissue, distant lymph nodes, or other organs like the lung, liver, brain, bone, or gastrointestinal tract. The cancer can be any thickness and might or might not be ulcerated.
- Recurrent: Recurrent melanoma is melanoma that has come back after treatment. It might be the recurrence of new tumor at the site of a previous tumor or in other body sites. Recurrence is most likely to occur within the first five years, but new tumors felt to be recurrences may show up decades later.
Malignant melanoma is a highly aggressive cancer that tends to spread to other parts of the body and may be fatal if not treated early. Apart from the stage, there are a number of other factors like the patient's age, overall health, location of the tumor, results of biopsy, and the depth of the tumor that plays an important role in determining the survival rates for melanoma.
Survival statistics are generalized numbers that has been accumulated based on five-year survival rate of many patients with the same condition in the past.
|Stage||5 year survival Rate|
|Stage 1 (thin melanoma, Localized)||100%|
|Stage 2 (thicker melanoma, local only)||80-90%|
|Stage 3 (local and nodal metastasis)||50%|
|Stage 4 (distant metastasis)||10-25%|
Survival rates give a generalized view but the outlook for cancer treatment depends on various factors that are unique to each individual. Hence, the survival rates cannot be used to precisely predict the outcome of a particular patient.
If melanoma skin cancer originates in the visible part of the body then being aware about the condition helps in early diagnosis. However, melanoma cancer can also occur in areas less visible or not accessible to us, in those cases regular health check-ups and tests can aid in detecting the hideous disease.
Here are some of the recommended tests and procedures to detect melanoma skin cancer.
- Physical Examination: Regular self exams may help to learn about the developments in moles, freckles and other skin marks that might be an indication of cancer. Check the areas more prone to skin cancer very minutely. During regular health check-ups, the physician would inspect your skin from head to toe and if anything suspicious is detected then other tests are suggested to confirm the abnormality.
- Biopsy: Biopsy is a procedure in which a small part of the skin would be taken out for investigation under a strong microscope. Biopsy procedures that are usually adopted to diagnose melanoma include:
- Punch biopsy: In this procedure, a tool with a circular blade is used to remove a round piece of skin around a suspicious mole.
- Excisional biopsy: In this procedure, the entire mole is removed along with a small border of normal skin.
- Incisional biopsy: In incisional biopsy, only the irregular part of a mole or growth is taken for laboratory analysis.
- Shave (tangential) biopsy: In this procedure, the top layer of the skin is shaved with a small surgical blade. An ointment is applied to the site to stop bleeding and soothe pain.
Here are a few more biopsies that may be recommended once cancer is diagnosed.
- Punch biopsy: In this procedure, a tool with a circular blade is used to remove a round piece of skin around a suspicious mole.
- Fine needle aspiration biopsy: In this procedure a thin, hollow needle is used to remove very small pieces of a lymph node or tumor. FNA biopsies are not invasive and do not causes much discomfort nor they leave any scar.
- Surgical (excisional) lymph node biopsy: In this procedure an enlarged lymph node is removed through a small incision in the skin. This type of biopsy is helpful when the size of the lymph node suggests the melanoma has spread there.
- Sentinel lymph node biopsy: A sentinel lymph node biopsy is done to confirm if the cancer has spread to nearby lymph nodes. In this procedure a small amount of a radioactive substance is injected into the area of the melanoma and after some time a special camera is used to see if it collects in one or more sentinel lymph nodes.
Once the radioactive area has been marked, the patient is taken for surgery, and a blue dye is injected in the same place as the radioactive substance. A small incision is then made in the marked area, and the lymph nodes are then checked and if any malicious node is detected then it is removed and looked at under a microscope.
Melanoma skin cancer is highly curable when it is detected at an early stage before the cancer cells has metastasized and spread to other parts of the body. The treatment opted for melanoma skin cancer depends on a number of factors including the stage of the cancer, patient’s health, age, past records and preference. Here we have discussed the treatment options according to the stage of the cancer.
Treating early-stage melanomas
Early stage melanomas are generally restricted to the site of origin only and the cancerous cells can be easily removed through a surgery.
Treating melanomas that have spread beyond the skin
If melanoma has spread beyond the skin, treatment options may include:
- Surgery: Surgery is the most preferred and effective line of treatment. The layer of skin along with the affected lymph nodes is removed through surgery.
- Chemotherapy: Chemotherapy is the process of using drugs to kill the cancer cells or inhibit the growth of such cells. Chemotherapy can be given intravenously or orally to the patient. Utmost care is to be taken while administering chemotherapy treatment as these are very strong drugs and may lead to a number of adverse effects.
- Radiation therapy: This treatment involves the use of high-powered energy beams to kill the cancer cells. Radiation therapy may be recommended after surgery to remove the lymph nodes. Care should be taken during radiation therapy as it increases the risk of several other cancer types.
- Biological therapy: Biological therapy boosts the immune system to fight cancer. These treatments are made of substances produced by the body or similar substances produced in a laboratory. Biological therapies used to treat melanoma include interferon and interleukin-2, ipilimumab, nivolumab, and pembrolizumab.
- Targeted therapy: Targeted therapy uses medications designed to target specific vulnerabilities in cancer cells. Some of the drugs used for targeted therapy to treat advanced melanoma are Vemurafenib, dabrafenib and trametinib. These drugs are only effective if your cancer cells have a certain genetic mutation.
Cancer treatment is a complex process and may involve high risk and toxic drugs that can trigger a cluster of other problems in the body. However, side effects of a particular drug or therapy varies from person to person as it depends on the body’s response, patient’s age and health as well as the immune system of the patient.
- Side effects of Biological therapies may include chills, fatigue, fever, headache and muscle aches.
- Side effects of targeted therapies vary, but tend to include skin problems, fever, chills and dehydration.
- Side effects of chemotherapy include damaging of nerves and pain, burning, tingling, or weakness or increased sensitiveness to heat or cold. Other side effects include hair loss, mouth sores, infection, bruising or bleeding.
- Radiation therapy may increase the risk of several other cancer. It also causes fatigue and weakness in the body.
In case the patient experiences any side effect of the treatment, he/she must report to the doctor immediately without any delay. Proper medications can be given to control these side effects and in case of more severe actions the treatment plan might also be changed.
Melanoma skin cancer is highly curable when it is recognized and treated early. But a delay in the treatment deems the chances of cure. As the cancer advances and spreads to other parts of the body, it becomes hard to treat and may result in fatal conditions. Though it is not the most common of the skin cancers, it causes the most deaths.
Regular health check-ups have shown phenomenal results in detecting cancer at an early stage. Apart from meticulous self examination, it is recommended to go for a complete health check up at least once a year. In case of high risk individuals the check up should be done in every six months.