Malignant Melanoma
The bottom layer of the epidermis in skin contains melanocytes that produce melanin, that is responsible for the skin colour. Besides the epidermal layer, melanocytes are found in the inner ears, bones, heart and in the middle layer of the eye. When skin with low melanin content is exposed to UV radiation, the nested melanocytes form moles on the face and the eyelids that may break into an aggravated form of skin cancer known as malignant melanoma. On the cancers affecting face and eyelids, malignant melanoma is one of the common cancers affecting people in the middle age.
Cause and Symptoms
Melanomas are caused by over exposure to UV radiations (315 – 280 nm) and, their absorption that leads to damage in the DNA. The degree of pigmentation, the age of the person and the amount of exposure to Sun determine the risk of being affected by malignant melanoma. Genetic mutations can also cause malignant melanomas.
The common symptoms of melanomas begin with appearance of moles that may itch and bleed. Very early signs of this cancer affecting the face and the eyelids can be observed by some changes in the existing mole in the body such as,
- Asymmetry of the mole
- Borders of the mole that are irregularly placed
- Colour in the mole is distributed unevenly
- Diameter of the mole is larger than ¼ inch
- Evolving period of the mole wherein, the colour, shape and the size keeps changing
Itching, bleeding and changing shape of the mole indicates the possibility of cancer that affects face and the eyelids. However, symptoms of malignant melanoma vary slightly for advanced melanomas wherein in the latter, the moles become firmer and continue to grow as elevated lumps on skin of face and eyelids. Such symptoms indicate the onset of nodular melanoma. People suffering from nodular melanoma experience acute symptoms such as nausea, loss of appetite and fatigue. If the melanomas are metastatic by nature, they can spread into surrounding lymph nodes, bones, abdomen and liver. Fair complexioned people are at a higher risk of being afflicted with malignant melanomas given the lower amount of melanin in their skin.
Nodular melanomas have a higher chance of occurrence in middle aged people. The other malignant melanomas on cancers involving face and eyelids are Lentigo Maligna Melanoma and Acral lantiginous melanoma. Lentigo Maligna melanoma affects the face and, spreads over to the other parts of the body slowly over the years. On cancers affecting the face and eyelids, malignant melanoma has been found to be more common in elderly people who have been exposed to Sun for most part of their lives. Another rare form of malignant melanoma is Acral lantiginous melanoma that affects palms, soles and toenails. They are known as the hidden melanomas and are prominent in people with dark complexion. They develop in areas that have had little exposure to Sun and, may occur under fingernails (Acral-lentiginous melanoma), genitals, GI tract, urinary tract and in the eye. Ocular melanomas can develop in the uvea beneath the sclera of the eye and, may lead to visual impairment.
Diagnosis
Diagnosis involves, screening tests and skin biopsies to evaluate the degree of this cancer affecting face and eyelids. A thorough skin examination is conducted to evaluate the changes in the size, colour and symmetry of the moles, birthmarks and freckles in the skin. Genitals, nails, scalp, soles of the feet and the space between the toes are also inspected to find anomalies, if any.
Prior to diagnosis of malignant melanomas, the stages of melanoma are assessed. To understand the spread of cancerous melanocytes into the layers of skin and to measure the thickness of the melanoma, Clark scale is used along with the Breslow scale. TNM staging is implemented if the melanoma has spread into the lymph nodes.
Malignant melanoma is categorised into five stages:
Stage 0 – Melanoma cells are found in the epidermal layer of the skin only.
Stage 1A – The cell thickness is less than 1mm. No sign of melanoma spreading into lymphatic system.
Stage 1B – The cell thickness is either less than 1 mm or somewhere between 1 mm and 2 mm. Melanoma on the skin is non-ulcerated. No indication of melanoma in lymphatic system.
Stage 2A – The cell thickness is less or equal to 2mm. Melanoma on the skin is ulcerated. No indication of melanoma in lymphatic system.
Stage 2 B – Melanoma cell thickness is between 2 mm and 4 mm. No sign of melanoma cells in the lymph nodes.
Stage 2C – Melanoma cell thickness is more than 4 mm and, is ulcerated. No sign of melanoma cells in the lymph nodes.
Stage 3A – Melanoma cells have spread into lymph nodes near the primary growth. Melanoma is non-ulcerated.
Stage 3B – Melanoma is ulcerated and has spread to more than 3 or 4 lymph nodes. No enlargement detected in lymph nodes. Ulceration may or may not be present in the melanoma
Stage 3C – Melanoma is ulcerated and is spread into more than three lymph nodes. Enlargement in the lymph nodes is detected.
Stage 4 – Melanoma has spread into lymphatic system and into internal organs of the body.
During the diagnosis, the thickness and size of the melanoma is assessed using a micrometer. If the thickness is more, a sentinel node biopsy is conducted to check if the tumour has spread beyond the epidermis into the lymphatic system. Malignant melanomas, if diagnosed at an early stage have a high success rate in treatment. However, if Stage IV is reached, the cancer has most probably spread into internal organs such as lungs and liver.
Biopsies are conducted to understand the degree of the malignant melanoma. In a Punch Biopsy, a piece of skin around the targeted mole is removed using a circular blade and, is examined thoroughly under a microscope to assess the division of melanocytes in the skin. In Excisional biopsy, the entire mole is removed with some skin around it. Whereas, in Incisional biopsy, the most asymmetrical section of the mole is removed.
Treatment
At an early stage, melanomas affecting face and eyelids are treated by surgically removing the affected moles on the skin. However, if they have spread into the lymphatic system, the affected lymph nodes are surgically removed to cull the further spreading of the cancer cells.
If the melanoma has advanced to Stage IV, chemotherapy is administered to the patient orally or, intravenously to kill the cancer cells. Radiation therapy is another effective means of treating malignant melanoma by engaging high powered X-ray beams on the site of treatment. It alleviates symptoms of melanoma if it has spread to other parts of the body. Certain medications are also administered through Targeted therapy to efface the cancer cells by targeting their vulnerability. However, targeted therapies work only if the cancer cells have undergone a certain kind of genetic mutation. Whether or not the cancer cells are vulnerable to the target therapy, is evaluated during the biopsy. Alternative treatments like Biological therapy also cull the spread of malignant melanocytes by boosting the immune system with externally made components that are usually made by the body. Patients treated with Biological therapy may experience chills, muscle aches, headache and fever as side effects of the treatment.
On cancers affecting face and eyelids as in malignant melanoma, the doctors usually advise the patients to avoid the Sun during its peak hours. Wearing sunglasses to protect the eyes and, wearing photo protective clothing aids in protection of the body from harmful UV radiations. A self examination of skin from head to toe, aids in early diagnosis of malignant melanoma, if any of the above mentioned symptoms are experienced.
Dr. Debraj Shome, an acclaimed oculoplastic surgeon has a vast expertise in treating dermatological cancers affecting face and eyelids such as malignant melanoma.