Skin Cancer Checks
The Ins and Outs of Skin Cancer
Dr. Chris Irwin, Dr. Anne Connell and Dr Mostafa Khalafalla are undergoing additional study towards a master’s degree in Skin Cancer and Dr. Elena Nefedova has professional certificates in skin cancer medicine. We hold weekly skin meetings and liaise extensively with academics in skin cancer. We actively teach junior doctors in skin cancer medicine as well. We believe we have one the most thorough skin checks in Melbourne.
Skin Cancer Is The Most Common Type Of Cancer.
Over 80% of all cancers in humans are skin cancers. Most (but not all) skin cancer is caused by radiation from the sun.
Australia the highest skin cancer rates in the world. 2 in 3 Australian’s are diagnosed with skin cancer by the age of 70.
The rate is even higher in those with white skin.
The most common types of skin cancer are:
- BCC (Basal cell carcinoma)
- SCC (Squamous cell carcinoma)
What does a skin cancer look like?
Unfortunately, skin cancer is so complex it is impossible to say in a few words. Any spot that is different to your regular spots should be reviewed by a doctor with special skills and experience in skin cancer
The most common concerning features patient describe to me
- Changing spots
- Itching or bleeding spots
- Sores or ulcers that don’t heal
- Spots that look different to everything else on your body
One of the most common misdiagnosed skin cancers I find are red itchy spots that are misdiagnosed (by skin specialists as well as GPs) as dermatitis or a simple skin rash.Any skin rash that stays in one spot and does not resolve with treatment (over weeks) should be considered as possible skin cancer until proven otherwise.
Melanoma is the most deadly skin cancer. It is one of the most deadly cancers in humans. 13,134 Australians were diagnosed with melanoma in 2014 alone (2). The majority of melanoma is caused by sunlight exposure (to UV), but can occur anywhere on the body including on the bottom and even between the toes.
One of the best things about melanoma is that most malignant melanomas arise as superficial tumors initially confined to the upper most layers on skin (the epidermis), where they remain for several months to years. During this stage, known as the horizontal or “radial” growth phase, the melanoma is almost always curable by surgical excision alone.
Melanoma can have many different appearances – some melanoma are not even pigmented and look to the untrained eye like a growing skin coloured pimple (amelanotic melanoma).
In general melanoma are pigmented (Brown, Black, Grey or Blue). Many people are worried about large and dark moles (naevi); but melanoma can has been diagnosed as small as 1-2 millimetres in size (6). In general technology like the skin mapping system we have is important in helping us diagnose melanoma as small as possible. This allows us to compare the smallest moles across your entire body to see if they have changed over time.
At our clinic the majority of melanoma we remove are superficial and small, the survival of these superficial tumours is excellent. Survival is mainly dependent on the depth of invasion of the melanoma into the skin. Doctors call this the “breslow thickness” – it is how deep the melanoma cells are as measured from one of the most superficial layers of skin – known as the “granular layer” of the epidermis. In general superficial melanoma (“melanoma in situ”) can be cured by minor skin surgery, and thin melanomas up to 1mm thick have very good chance of cure by minor surgery alone.
Sentinel Lymph Node biopsy (SLNB)
Lymph nodes are part of the immune system in the body. If a skin cancer spreads through the body, it will usually spread to a lymph node first. By performing a biopsy of the closest lymph node to a diagnosed melanoma, surgeons can give a patient better information about their survival. As of January 2018 there is no evidence that Sentinel Lymph Node Biopsy (SLNB) will help patient survival, but having it performed may allow patients access into drug trials at large melanoma centres.
Sentinel Lymph Node biopsy (SLNB) is a procedure where a surgeon injects blue dye and a mild radioactive substance into the area where a diagnosed melanoma was (the melanoma has usually already been removed). The surgeon then follows where the blue dye and mild radioactivity drains to (the first lymph node). This is called the sentinel lymph node. The surgeon then removes this lymph node and sends it to the lab to be examined under the microscope for any evidence of spread of the melanoma.
Most melanoma removed do not need a Sentinel Lymph Node biopsy. For those >0.75-1mm or over in thickness a conversation about SLNB will occur with your doctor.
Basal Cell Cancer (BCC)
Basal Cell Cancer (BCC) is the most common cancer in humans. It is a type of cancer that gets grouped into “Non-Melanoma Skin Cancer” or NMSC. Basal Cell Cancer (BCC) accounts for around 70% of all skin cancers.
The good thing about Basal Cell Cancer (BCC) is that it is (in general) the most curable skin cancer. It is very rare (but not impossible) for a BCC to metastasise (spread through the body). Sometimes (still rare) however BCC can grow down a nerve. This is called perineural spread. This can make a skin cancer very hard to treat and why even BCC should be treated early and with respect.
Risk Factors for Basal Cell Cancer
- Sun exposure is the most important environmental cause of BCC, and most risk factors relate directly to a person’s sun exposure habits or susceptibility to solar radiation. These risk factors include having fair skin, light-colored eyes, red hair, northern European ancestry, older age, childhood freckling, and an increased number of past sunburns [18-20].
- The frequency and intensity of sun exposure may also be important. Solar exposure in intermittent, intense increments increases the risk of BCC more than a similar dose delivered more continuously over the same period of time
- Tanning Beds / Solarium use
- Arsenic exposure – usually in occupations
- Arsenic compounds, which are designated hazardous substances, are used in agriculture (as an additive to feed), and insecticides, herbicides, larvicides, and pesticides; in pigment production; in the manufacture of glass and enamels, textile printing, tanning, taxidermy, and anti-fouling paints; to control sludge formation in lubricating oils; as an alloying agent to harden lead base bearing materials; with copper to improve its toughness and corrosion resistance; and in a number of laboratory procedures. Arsenic compounds are also used to preserve wood (eg in the treatment of telecommunications poles).
- Medical light treatment for skin diseases such as psoriasis
- Previous radiation treatment – usually for skin conditions (in the past doctors used radiation to treat fungal infections and acne) and childhood radiation treatment. Usually there is a gap of around 20 years between radiation exposure and subsequent BCC growth.
Treatment for Basal Cell Cancer
Usually Basal Cell Cancer (BCC) can be removed simply via minor surgery under local anaesthetic. When removed with a good margin (at least 0.5mm) there is a 97% cure rate. This does mean however that 3% of BCC will recur in the same spot despite the best treatment.
Imiquimod(Aldara) – Sometimes low risk BCC lesions can be treated with a cream for 6-12 weeks. Imiquimod works by stimulating the immune system causing inflammation, which can destroy the cancer cells. In general it is less effective than surgical removal which is the preferred treatment method.
Cryotherapy and curettage (C&C) or Diathermy and curettage (D&C) – for low risk lesions sometimes the doctor may recommend C&C or D&C. This involves “scraping” out the cancer with a tiny curette and then freezing (cryotherapy) or “burning” (electrocauterising) the base of the lesion. This technique relies on the fact that cancer is less firm than the surrounding normal skin, in many cases allowing you to completely “scrape” it out. For added safety the base is then either “frozen” or “electrocauterised”. It should be noted that cure rate is in most cases higher with complete surgical excision and you should talk to your doctor about the best method for you.
Squamous Cell Carcinoma (SCC)
Squamous cell cancer (SCC) is the second most common type of skin cancer after Basal Cell Cancer (BCC). While Basal Cell Cancer is thought to come from the hair follicles in skin, Squamous Cell Cancer (SCC) comes from the skin cells themselves.
Squamous cell cancer is not as “bad” as melanoma, but unfortunately too many people still die of this curable disease. In 2015 the skin cancer council states that there were 642 deaths in Australia attributed to Non-Melanoma Skin Cancer (NMSC). The Majority of these deaths were from SCC.
SCC often grows rapidly over weeks to months, different to Melanoma and Basal Cell Cancer (BCC) which often grow more slowly.
Symptoms of SCC may include:
- thickened red, scaly spot
- rapidly growing lump
- looks like a sore that has not healed
- may be tender to touch.
Risk factors for SCC
The most important risk factor for Squamous cell cancer (SCC) is sunlight exposure – specifically UVB. A notable difference with other skin cancer (BCC and melanoma) is that cumulative sun exposure is the most important cause. BCC and melanoma are more caused by intense intermittent sun exposure (eg sunburns or sunblistering).
Medical light treatment for skin conditions eg. Psoriasis
Previous radiation – eg for previous cancer
Immunosuppression – eg after organ transplant (kidney or heart), long term prednisolone use, or any other cause
Chronic inflammation of the skin – sometimes Squamous Cell Carcinoma (SCC) can be caused by chronic inflammation of the skin – eg an old scar or burn
Smoking – cigarette smoking may increase SCC risk by 1.5x
Treatment for SCC
- Surgical – The main treatment of SCC is surgical excision. When a cancer has been surgically removed with adequate margins the chance of cure is very high (but not 100%). Even with the best treatment around 5% of surgically removed Squamous Cell Carcinomas regrow in the same location. That is one of the reasons why it is important to continually be aware of your own skin and have regular skin checks after a diagnosis.
- Cryotherapy & Curettage (C&C) or Diathermy & Curettage (D&C) (see treatment for BCC)
- Radiation – Sometimes Squamous Cell Carcinoma (SCC) is treated with radiation. This is not a commonly used treatment today, and when it is used often it is because the patient is otherwise not a good candidate for surgery (eg. old age, poor health, limited life span for other reason). Radiation has
- Efudix (5-FU/ 5- Fluro-Uracil) – Efudix is a cream that interferes with DNA synthesis or copying. Cancer cells tend to divide more often than normal cells and therefore have their DNA copied more often. Cancer cells also tend to not be as good at repairing mistakes in the DNA copying compared to normal cells. This means that cancerous and precancerous skin cells are affected more by efudix than normal cells. We do not use efudix for invasive Squamous Cell Carcinoma, but sometimes (after discussing the pros and cons) may use efudix to treat Squamous Cell Carcinoma in situ (SCCis) which is also known as Bowen’s disease. We also use it to treat Actinic Keratosis (AK) – a lesion that is precancerous towards SCC.
- A full-face course has been shown to substantially reduce the risk of cutaneous squamous cell carcinoma (SCC) developing in the treated site during the following year. (1)