SKIN CANCER (NON MELANOMA)
Skin cancer is the disease resulting from uncontrolled growth of skin cells. To understand well about this disease, it is important to at least have knowledge on structure and function of skin.
Skin is the largest organ in the body. It acts as a barrier to protect the body from injury and infection, storing water and fats, control of body temperature and production of vitamin D. like all other body tissues, skin is made up of different cells. Skin is made of three layers.
• Epidermis. The outer layer of skin.
• Dermis. The middle layer of skin.
• Subcutaneous layer. The inner most layer of skin containing fats.
Epidermis is the layer where most of skin cancers originate. Epidermis is mainly made up of four types of cells. Keratinocytes which is subdivided into basal cells and squamous cells, melanocytes, Langerhans cells and Merkel cells.
Skin cancer results from uncontrolled growth of those cells but most cases of skin cancer are as results of uncontrolled growth of the following cells that make up epidermis.
• Squamous cells. These are flat cells that are tightly parked together to make up the top layer of skin and form the thickest layer of the epidermis. These cells eventually die and become the surface of your skin. As time goes our body sheds these dead skin cells.
• Basal cells. These are the cells making the lower layer of epidermis. Basal cells multiply continuously and move upward to replace squamous cells that are shed out of the skin. As they move up, basal cells flattens and change into squamous cells.
• Melanocytes. These are melanin pigment producing cells. Melanin is the pigment that gives skin its color. On exposure to sun ultraviolet radiations, melanocytes make extra melanin to try to protect the skin from getting burnt. Melanocytes are the cells that can change and lead to development of melanoma.
Dermis is a layer of the skin below (underneath) epidermis. The dermis contains the roots of hairs (follicles), sweat glands, blood and lymph vessels, and nerves that are held in place by collagen, a protein that gives skin its elasticity and strength.
Types of skin cancer
There are three main types of skin cancers depending on their origin. These are squamous cell carcinoma (SCC), basal cell carcinoma (BCC) and melanoma. SCC and BCC are also called Keratinocytic or Non melanomas. The rare types of skin cancer include Merkel cell carcinoma and angiosarcoma.
• Squamous cell carcinoma (SCC). This type of skin cancer that develop from squamous cells of the epidermis. Usually appears on parts of the body most often exposed to the sun, such as the head, neck, hands, forearms and lower legs. It can also start anywhere on the body including lips, anus, woman vagina and other parts that have been damaged by chemicals, burned or exposed to radiations. Squamous cell carcinoma can grow quickly over several weeks or months and spread to other parts if left untreated.
• Basal cell carcinoma (BCC). Basal cell carcinoma is the type of skin cancer that develop from basal cells of the epidermis. This type of cancer commonly develops on areas of the body that receive high sun exposure, such as the head, face, neck, shoulders, back, lower arms and lower legs. It can also start anywhere on the body due to various reasons including long term side effects of radiation therapy to children. This type of skin cancer usually grows slowly and rarely spreads to other parts of the body.
• Melanoma. This type of skin cancer develops from melanocytes. Melanoma is considered to be the most serious type of skin cancer because it is more likely to spread to other parts of the body such as the lungs, liver, brain and bones. In this document, the discussion will be of Keratinocytic (Non melanoma) skin cancers (SCC and BCC), melanoma has been discussed on the other separate document. So for more information on melanoma please visit melanoma section.
Risk factors of skin cancers (Non melanoma)
When it comes to cancer, anything that increases your probability of developing cancer is called a risk factor. Risk factors only influence development of cancer but it does not directly cause cancer. Sometimes people with risk factors do not develop the disease while those with no risk factors do develop the disease. Knowing risk factors will help you live your life making some better healthy choices to reduce the risk. The following factors may increase your risk of developing non-melanoma skin cancers.
• Exposure to ultraviolet radiations. Ultraviolet radiations are naturally produced by sun but also can be produced by other artificial sources such as tanning beds. People who spend a lot of time exposed to sunlight have increased risk of developing skin cancers.
• Personal history of skin cancers. Those with the history of any form of skin cancers are at increased risk of developing another skin cancer at some point of their life.,
• Some inherited conditions. There are some conditions once inherited are said to increase a person`s chance of developing some skin cancers. These conditions include nevoid basal cell carcinoma syndrome, epidermolysis bullosa simplex syndromes, xeroderma pigmentosum and albinism.
• History of sunburns and fragile skin. Skin that has been burned, sunburned, or injured from disease has a higher risk of skin cancer. Squamous cell and basal cell carcinoma occur more often in people who have more exposure to the sun or other sources of UV radiation over their lifetime.
• Weakened immune system. Those with weakened immune system due to various reasons are said to be at increased risk of developing skin cancer especially squamous cell carcinoma.
• Fair skin. People with fair skin that burns easily rather than tan, are at increased risk of developing skin cancer.
• History of radiation therapy. Those that had radiation therapy at some point of their life especially during childhood, are at increased risk of developing other cancers including skin cancer at some point of their life.
Prevention of skin cancers
To prevent something you need first to know what causes it. Since the specific cause of skin cancer is still not clear, then there is no proven way to completely prevent development of skin cancer but there are ways that may help to lower the risk of developing it. These include the following,
• Avoid and reduce exposure to ultraviolet radiations. This is trough reducing time you while exposed to the sun and avoid using tanning beds.
• Use sun protective clothing. This involve wearing wide-brimmed hat that shades the face, neck, and ears. Clothes made from fabric labeled with UV protection factor (UPF) may provide better protection. UV-protective sunglasses are also recommended
• Avoid weakening your immune system. Since low immunity increase your chance of developing melanoma then avoiding to weaken your immune system will reduce your risk of developing the disease. This include avoiding practices that may lead to HIV infections such as having unsafe sex.
• Regular examination of skin. Regular examination of skin may help you notice any changes that may be dangerous if left unattended.
Early detection and screening
When it comes to cancer, early detection normally provide better treatment outcome. When skin cancer is found early, chances for better treatment outcome are very high. For most cancers, early detection has been greatly contributed by the presence of screening processes
Screening is the process of running some tests to someone with no symptoms of the disease with the intention of determining presence or absence of the disease. Although some people have a higher risk of getting skin cancers than others, but it’s important to know that anyone can develop skin cancer. There are two main ways that may help in early detection of the disease.
• Self-examination. It is good to examine your skin to check for presence of anything abnormal including abnormal moles. It is crucial to know the pattern of moles, blemishes, freckles, and other marks on your skin so that you’ll notice any changes. It is recommended to perform Self-examinations in front of a full-length mirror in a brightly lit room. Also it helps to have another person check the scalp and back of the neck.
• Medical examination. This is done by health care professionals. If your doctor finds something abnormal from your skin including abnormal moles, he/she may recommend that you visit a doctor specialized in skin diseases (dermatologist) for more examination.
Signs and symptoms of non-melanoma skin cancers
People with non-melanoma skin cancer may experience the following signs and symptoms. Sometimes, people with non-melanoma skin cancer do not have any of these changes. Or, the cause of those symptom may be another medical condition that is not cancer, hence seeing your doctor upon experiencing any of those symptoms is advised.
• Spots and sores that do not heal for several weeks
• Sores that is crusty which may/may not bleed.
• Growth which may be itch, irritated or sore.
• Wart like growths
• raised lumps that indent in the center
• raised and scaly patches
Diagnosis of non-melanoma skin cancers
Diagnosis is simply an identification of nature of an illness. Doctors use tests to find tests to find illness including cancer. Through tests doctors are able to determine if cancer has spread to other organs in the body or not. Tests can help doctors to decide suitable treatment for the disease and predict prognosis (outcome of treatment).
When running those diagnostic tests, your doctor will consider some of the factors including;
• Results of your previous tests
• Your general health condition
• Type of cancer suspected
• Your age
Diagnostic tests for non-melanoma skin cancer include the following;
• Physical examination and medical history. Physical examination is first done by you (self-examination). When you notice anything suspicious, your doctor will examine you, paying particular attention to any spots you have identified as changed or suspicious. The doctor will ask if you or your family have a history of the disease.
• Biopsy. This involve taking sample of tissue for assessment of cells under the microscope in the laboratory. This is done by a pathologist (specialized doctor in assessing cells under microscope). During this procedure, the suspected skin lesion is removed, usually after a local anesthetic helps numb the area. The doctor also removes an area of healthy tissue around the lesion, which is called the margin.
• Imaging. Although are not the main diagnostic tests for skin cancers, but imaging tests like CT scan, MRI scan and PET scan can be used to examine lymph node and other organs involvement which is normally very rare.
Staging of non- melanoma skin cancers
Staging is a standard way used by cancer care team to explain how far the cancer has grown or spread. Once diagnostic tests has helped to establish a probable diagnosis of non-melanoma skin cancer, the next issue is deciding suitable treatment option for the disease. Staging has enabled oncology team to decide on the suitable treatment option and predict patient`s prognosis which is chance of recovery.
Basal cell and squamous cell carcinoma usually do not spread to other parts of the body. On rare occasions, a person’s lymph nodes may be removed to find out if the cancer has spread, or metastasized. Due to that reason, non-melanoma skin cancers are normally not staged.
Treatment of non-melanoma skin cancers
After being diagnosed with skin cancer, your doctor will give you the news and most of times it is very difficult for people to accept the news due to the nature of disease itself. After hearing the news, many will start asking themselves different questions like,
• Am I going to be covered with marks all over the body?
• Am I going to infect others who contact me?br
• What should I do?
• Is there treatment for this?
Those are some of the first question many will start to ask themselves. Your doctor will be there to help you with answers.
Making treatment decision
When helping you with some of your questions that you may have, one of the things that you will talk about with your doctor is availability of any possible solution for your case. So here comes the crucial part that include making treatment decision as there are many treatment options and in order to decide what is the right choice for you, you will need to be careful and get all the help you can get in making decision.
Talk with your doctor
Your doctor will discuss with you about all the treatment options available for your case. During the discussion you will talk about their goals and possible side effects. Among other things that your doctor will consider when presenting to you the options are;
• Your age
• Any other serious health conditions you have
• Type and stage your cancer
• Chances that the treatment option will cure you or help in some any way
• How do you feel about the possible side effects from treatment options?
After listening to the doctor, do not rush to make the decision but take your time to absorb the information that you have just received and ask questions if there is anything that you have not understood or not sure about. Many people prefer to have a family member or friend with them in order to take part in the discussion making, taking notes or simply listen.
After hearing all the options available from your doctor, you may want to get a second opinion from another specialist to confirm or seek more clarification on your doctor’s recommendations or reassurance that you have explored all of your options. Some doctors can even send you together with your initial results to another specialist for more opinions on your case.
Take part in clinical trials
Clinical trials are new drugs or modified mode of treatment or new treatment combination for cases like yours that are to be tested if they are effective to be used as standard care treatment options or not. Your doctor or nurse will discuss with you if you want to take part in clinical trial.
Over the years, trials have improved treatments and led to better outcomes to people diagnosed with various diseases including cancer. If you have decided to take part in clinical trial, you can also withdraw at any time
Treatment of skin cancer requires a team of doctors and other health care professionals. This team work together and it is called multidisciplinary team. Team may vary depending on the treatment option for a particular case. But generally multidisciplinary team for treatment of skin cancer includes, surgical oncologist, medical oncologist, radiation oncologist, dermatologist, pathologist and other health care professionals like oncology nurses, reconstructive surgeon, physiotherapist and palliative care team
Surgery is the treatment option that involve removing the affected area through operation. For cases at an early stage, surgery is the preferred treatment option. But for advanced cases it can be given in combination with other treatment options like radiotherapy. Surgery is done by surgical oncologist. Depending on the stage of the disease, surgery of skin cancer can be done in the following ways;
• Wide excision. Involve cutting out the affected area of the skin as well as small amount of surrounding normal-looking skin. Removing more tissue around the cancer than was cut out during the biopsy reduces the risk of cancer coming back. Pathologist has to verify if the removed skin surrounding melanoma doesn`t have cancer cells.
• Cryosurgery (freezing). This involve the use of liquid nitrogen to freeze the tumor. The liquid nitrogen will sting when it is first applied to the skin, and then the skin will blister and shed off. With this option, more than 1 freezing may be needed.
• Mohs` surgery. This is a microscopically controlled surgery. The doctor removes the cancer little by little, checking each section of tissue under a microscope. They keep removing tissue until they see only healthy tissue under the microscope, and then close the wound with stitches or, sometimes, a skin flap or graft.
• Skin flap – Loose skin or tissue is taken from an area close to the wound and placed over it using stitches.
• Skin graft – A thin piece of skin from another part of the body is stitched over the wound.
Side effects of surgery
The side effects of surgery will depend on the location and extent of surgery. The possible side effects include the following;
• Wound pain. After surgery, it is common to have pain after surgery. Sometimes pain can go away as wound heals but sometimes pain can stay for a longer period and can be relieved by medication.
• Lymphedema. If lymph nodes have been surgically removed, swelling of the neck, arm or leg is the most common problem that can occur. Lymphedema happens due to a build-up of lymph fluid in the affected part of the body. Sometimes this fluid needs to be drained by having a needle inserted into the fluid-filled cavity.
Radiation therapy is the use of high energy x-ray or other radiation particles to kill cancer cells. It is normally used on skin cancers that that are hard to treat with surgery such as, cancer has spread too deep and having surgery alone cannot help, or after surgery so as to prevent cancer from coming back, or it is for palliation purpose to those at very advanced stage and there is no possibility of cure.
When dealing with skin cancer, external beam radiotherapy is a type of radiation therapy used. External beam radiation therapy involve irradiation of tumor from the source or machine which is outside the body.
Side effects of radiation therapy
Side effects of radiation therapy depends on the site of irradiation and dose used. The side effects normally disappears soon following completion of treatment. But the side effects can also be managed if they become too severe. Side effects of radiation therapy include the following;
• Skin reactions (sunburn like) and change in color.
• Loss of hairs at the site where radiations enters the body.
Some skin cancers can be treated using creams, lotions or gels prescribed by a doctor that you apply yourself. Those creams or gels or lotions that you will be given are chemotherapy drugs made in form of cream or lotions or gels.
Chemotherapy is the use of drugs to destroy cancer cells, usually by stopping the cancer cells’ ability to grow and divide. These drugs are usually applied to the skin every day for several weeks. They may cause skin inflammation or irritation, which will go away once treatment is finished