Our Skin
Our skin is the largest organ of our body and its health is the easiest to monitor.
We can see and feel our skin, so we tend to be more familiar with the health of our skin than our other organs. We know when our skin is dry and when it starts to show signs of aging. The downside with our familiarity with our skin is that we tend to take it for granted, and we do not get particularly concerned when it is under distress. However, the body is an integrated system, in which our skin plays an important role; our tendency to underestimate the importance of healthy skin can be detrimental to our health.
The Sun and Your Skin
One of the goals of the Save Your Skin foundation is to increase awareness of skin cancer, and make information about it more available. The health benefits of vitamin D for our skin, and the potentially damaging consequences of sunscreens, are currently a matter of debate. This debate is an important one, which will lead to a better understanding of how we can best protect our skin and our health.
Contributing factors to melanoma and non-melanoma skin cancers include:
- unprotected and/or excessive exposure to ultraviolet (UV) radiation
- a fair complexion
- the tendency to freckle
- occupational exposures to coal tar, pitch, creosote, arsenic compounds, or radium
- some medications, such as immunosuppressants
- family history of skin cancers
- multiple or atypical moles
- severe sunburns, especially as a child
If you have any concerns about your skin and possible skin cancer, contact your physician immediately. More information about the diagnosis process can be found here.
Types of Skin Cancer
Cancer is a disease of the cells, thus skin cancer is a disease of our skin cells.
There are 3 types :
Types of Melanoma
There are three different types of melanoma: cutaneous melanoma, mucosal melanoma, and ocular (or uveal) melanoma.
Cutaneous Melanoma
There are four different types of cutaneous melanoma, which are determined by microscopic examination of a biopsy sample.
Mucosal Melanoma
Mucosal melanoma develops in the lining of the respiratory, gastrointestinal, and genitourinary tracts. It is a rare form of melanoma, making up only about 1% of melanoma cases and is often seen in the elderly and diagnosed at an advanced stage. Approximately 50% of mucosal melanomas begin in the head and neck region, 25% begin in the ano-rectal region and 20% begin in the female genital tract. The remaining 5% include the esophagus, gallbladder, bowel, conjunctiva and urethra.
More information about mucosal melanoma:
Melanoma Research Foundation
Ocular Melanoma
Ocular melanoma is rare, affecting only five in a million people. While it represents only 5% of melanomas, it is rapid and aggressive, accounting for 9% of melanoma deaths. There are no established risk factors but it often occurs in blue-eyed, fair-skinned people over sixty years old. Treatment can be successful if the tumours in the eye are caught early. 50% of tumours will metastasize, usually in two to five years. Ask your doctor about a gene profile of the tumour to determine if it will metastasize. Metastasis is to the liver in 90% of cases, but can also appear in the lungs, bones, brain or abdomen.
More information about ocular melanoma:
Eye cancer Forum UK
Ocular Melanoma Foundation
Alberta Health Service: Uveal Melanoma Guideline
Canadian Cancer Society
BC Cancer Agency
Studies in uveal melanoma with Selumetinib:
1. A Randomised, Double-Blind Study to Assess the Efficacy of Selumetinib (AZD6244: ARRY-142886) (Hyd-Sulfate) in Combination With Dacarbazine Compared With Placebo in Combination With Dacarbazine as First Systemic Therapy in Patients With Metastatic Uveal Melanoma (SUMIT) clinicaltrials.gov: NCT01974752. This is a Phase 3 Global clinical trial that has recently closed in Canada, the study is ongoing but not recruiting patients
2. Effect of selumetinib vs chemotherapy on progression-free survival in uveal melanoma: a randomized clinical trial. Carvajal, R.D., JAMA. 2014 June 18; 311(23): 2397–2405.
3. Therapeutic Implications of the Emerging Molecular Biology of Uveal Melanoma, Patel, M. et al, Clinical Cancer Research, 2011, 17; 2087. This is a retrospective analysis of 20 patients with uveal melanoma treated in a completed study of selumetinib vs. TMZ.
Study examining addition of Dacarbazine to Selumetinib:
1. Selumetinib plus dacarbazine versus placebo plus dacarbazine as first-line treatment for BRAF-mutant metastatic melanoma: a phase 2 double-blind randomised study, Robert C, et al. Lancet Oncology, 2013.[/ordered_list]
Actinic Keratosis and Bowen’s Disease
Precancerous conditions of the skin have the potential to develop into non-melanoma skin cancer. The most common precancerous conditions of the skin are actinic keratosis and Bowen’s disease.
Actinic Keratosis
Actinic keratosis is also called solar keratosis. It is often found on sun-exposed areas of the skin in middle aged or older people. Actinic cheilitis is a related condition that usually appears on the lower lips. A person with one actinic keratosis will often develop more. The number of actinic keratoses often increases with age. The presence of an actinic keratosis indicates that a person’s skin has suffered sun damage.
Actinic keratoses are considered slow growing. They often go away on their own, but they may come back. Approximately 1% of actinic keratoses develop into squamous cell carcinoma (SCC) if left untreated. Treatment is required because it is difficult to tell which keratoses will develop into cancer.
Risk Factors:
The following risk factors may increase a person’s chance of developing actinic keratosis:
- overexposure to ultraviolet B (UVB) radiation from the sun
- increased age
- fair skin
- weakened immune system
- previous PUVA (psoralen + UVA) therapy
Signs and Symptoms:
Actinic keratosis is most often seen on skin that is frequently exposed to the sun, such as the face, the backs of hands or a balding scalp. The signs and symptoms of actinic keratosis may include:
- small, rough patches that may be pink-red or flesh coloured
- an initially flat surface that becomes slightly raised and wart-like
Diagnosis:
Actinic keratosis is diagnosed during an examination of the growth. If it does not go away with treatment or shows signs of developing into SCC, a skin biopsy will be done.
Treatment:
Treatment options for actinic keratosis depend on the number and location of keratoses. The treatment may include one or a combination of the following:
- topical chemotherapy
- 5-fluorouracil (5-FU, Efudex)
- ingenol mebutate (Picato)
- topical biological therapy
- imiquimod (Aldara or Zyclara)
- cryosurgery
- often used on single spots
- may also be used for many small, raised spots
- surgery
- simple surgical excision
- curettage and electrodesiccation
- may be used on many large spots
- chemical peeling
- laser surgery
- photodynamic therapy
Treating actinic keratosis:
The main types of treatments for actinic keratosis are:
- Topical therapy
- Liquid nitrogen / cryotherapy
- Photodynamic therapy
Sometimes a combination of these therapies are used. The choice of treatment may vary with the location, type and extent of the lesions, experience with previous treatments, the presence of subclinical lesions, patient preference, and changes in a lesion that may indicate malignancy.
Bowen’s Disease
Bowen’s disease is an early form of squamous cell carcinoma (SCC). It may be called squamous cell carcinoma in situ. Bowen’s disease involves cancer cells in the epidermis or outermost layer of the skin. Although it can’t spread to the lymph nodes, Bowen’s disease can spread into the deeper layers of the skin if left untreated. When it spreads, it becomes an invasive SCC that then has the potential to spread into the lymph system.
Risk Factors:
The following risk factors may increase a person’s chance of developing Bowen’s disease:
- overexposure to ultraviolet B (UVB) radiation from the sun
- increased age
- previous radiation therapy
- weakened immune system
- Infection with human papillomavirus (HPV) is associated with Bowen’s disease of the anus and genital skin.
- arsenic exposure
Signs and Symptoms:
Bowen’s disease is most often seen on the legs, backs of hands, fingers or face. The signs and symptoms of Bowen’s disease may include:
- a reddish scaly patch, which is sometimes crusted – may be a single patch or multiple areas
- a windblown appearance of the skin
- larger, redder and scalier patches than actinic keratoses
Diagnosis:
If the signs and symptoms of Bowen’s disease are present, or if the doctor suspects Bowen’s disease, a biopsy will be done to make a diagnosis. The type of biopsy may be:
- shave biopsy
- punch biopsy
Treatment:
Treatment options for Bowen’s disease depend on the number and location of spots. The treatment may be one or a combination of the following:
- surgery
- simple surgical excision
- curettage and electrodesiccation
- topical chemotherapy
- 5-fluorouracil (5-FU, Efudex)
- topical biological therapy
- imiquimod (Aldara or Zyclara)
- cryosurgery
- photodynamic therapy
BRAF (gene)
BRAF is a human gene that makes a protein called B-Raf. The gene is also referred to as proto-oncogene B-Raf and v-Raf murine sarcoma viral oncogene homolog B, while the protein is more formally known as serine/threonine-protein kinase B-Raf.[2][3]
The B-Raf protein is involved in sending signals inside cells, which are involved in directing cell growth. In 2002, it was shown to be faulty (mutated) in some human cancers.[4]
Drugs that treat cancers driven by BRAF mutations have been developed. Two of these drugs, vemurafenib[5] and dabrafenib are approved for treatment of late-stage melanoma. Vemurafenib was the first drug to come out of fragment-based drug discovery.
Health Canada has approved Tafinlar™ (dabrafenib mesylate) and Mekinist™ (trametinib) for patients with unresectable (melanoma that cannot be removed by surgery) or metastatic (melanoma which has spread to other parts of the body) melanoma.
TafinlarTM, a BRAF-inhibitor, is indicated as a monotherapy oral treatment for unresectable melanoma or metastatic melanoma in adult patients with BRAF V600 mutation. MekinistTM, a first in class MEK-inhibitor, is also indicated as a monotherapy oral treatment for unresectable or metastatic melanoma in adult patients with BRAF V600 mutation. For both treatments, a validated test is required to identify BRAF V600 mutation status.
Health Canada has also just approved Cotellic (cobimetinib) in combination with Zelboraf (vemurafenib) for the treatment of patients with unresectable or metastatic melanoma with a BRAF V600 mutation. Melanoma – a type of skin cancer that develops in the cells (melanocytes) that produce the pigment that gives skin its colour1 – impacts close to 7,000 Canadians each year, and approximately 50 per cent of all cases are BRAF-positive. More than 1,150 people in Canada died last year as a result of the disease, making it the most serious type of skin cancer today.
The new combination therapy offers physicians a treatment option that builds on their experience with Zelboraf, another Roche medicine approved for the treatment of and shown to improve survival for people with BRAF V600 mutation-specific unresectable or metastatic melanoma. When used in combination, Cotellic (a MEK inhibitor) and Zelboraf (a BRAF inhibitor) has been observed to reduce cancer cell growth longer than with Zelboraf alone.
Steps of a Skin Cancer Self-Exam
- Using a mirror in a well lit room, check the front of your body -face, neck, shoulders, arms, chest, abdomen, thighs and lower legs.
- Turn sideways, raise your arms and look carefully at the right and left sides of your body, including the underarm area.
- With a hand-held mirror, check your upper back, neck and scalp. Next, examine your lower back, buttocks, backs of thighs and calves.
- Examine your forearms, palms, back of the hands, fingernails and in between each finger.
- Finally, check your feet – the tops, soles, toenails, toes and spaces in between.
Canadian Dermatology Association, patient handout “Melanoma Skin Cancer: Know the Signs, Save a Life” 2009.
Detection
Moles, spots and certain growths on the skin are usually harmless, but not always. That is why it is important to examine the skin all over your body once a month, and have a physician check your skin once a year.
Look for the following “ABCDE” warning signs:
- Asymmetry: Do the two halves not match if you imagine drawing a line through the mole?
- Borders: Are the edges uneven, scalloped or notched?
- Colours: Is there a variety of shades (brown, red, white, blue or black)?
- Diameter greater than 6mm: Is the mole the size of a pencil eraser or larger?
- Evolution: Has there been a change in size, shape, colour, or height? Has a new symptom developed (such as bleeding, itching or crusting)?
If you detect any of these warning signs, see a physician promptly. It is particularly important for you to select a physician who specializes in skin cancer and is trained to recognize a melanoma at its earliest stage.
Canadian Dermatology Association, patient handout “Melanoma Skin Cancer: Know the Signs, Save a Life” 2009.
Follow-Up and Monitoring
Follow-up after melanoma treatment depends on the stage of the melanoma. A melanoma diagnosis increases the risk of another melanoma. Therefore, your doctor will perform a full-body skin examination, at least every year, for the rest of your life.
Self-monitoring
Your doctor will also teach you how to examine your skin and lymph nodes. You should examine your skin at least monthly. Make sure you check the back of your body. Use a mirror or have someone check for you. Look for changes in moles, any new growths, sores that do not heal, and abnormal areas of skin.
Contact your doctor right away if you notice any abnormalities. Your doctor may also recommend that you examine your lymph nodes every month. A schedule like the following one is followed if you have no signs or symptoms of melanoma.
If you do develop new signs or symptoms, your doctor will investigate them and determine appropriate treatment and follow-up based on your test results.
More information about melanoma staging can be found here.
The UV Index
The UV index is a simplified measurement system for the sun’s damaging rays and a guideline to protection.
UV Index:
- 0-2 – Low Risk – minimal sun protection required (unless near water or snow). Wear sunglasses if bright.
- 3-5 – Moderate Risk – take precautions – wear sunscreen, sunhat, sunglasses, seek shade during peak hours of 11 am to 4 pm.
- 6-7 – High Risk – wear sun protective clothing, sunscreen, and seek shade.
- 8-10 – Avoid the sun – seek shade – wear sun protective clothing, sun screen & sunglasses. White sand increases UV radiation exposure.
- 11 + – Take full precautions. Unprotected skin can burn in minutes. Avoid the sun between 11 am and 4 pm, wear sunscreens & sun protective clothing.
Sources: Health Canada – Canadian Cancer Society – Shade Foundation – BC Cancer Foundation – AIM at Melanoma
monthly self-exams are key to early detection
Making awareness and education available is crucial. Since 2006, the Foundation has worked to raise awareness of melanoma and non-melanoma skin cancers focusing on education, prevention and the need for improved patient care.[/action]
