SURGERY FOR SKIN CANCER.
Let’s run through the types of basic Skin Surgery in order of Cost & Simplicity.
Let’s run through the types of basic Skin Surgery in order of Cost & Simplicity.
The spray-gun is a common sight at skin cancer clinics!
Cryotherapy is freezing treatment & often used in the skin cancer clinic. The temperate of Liquid nitrogen is -195.6°C. The skin cells are damaged both during the freezing treatment itself and the thaw. Different types of skin cell and skin cancer cell are killed at different temperatures.
The lesion freezes from the centre outwards. The skin directly under the targeted area is frozen at a deeper level than the skin at the edge of the frozen area.
How do does the skin cancer doctor know deep the freeze is going? By looking at the ice circle on the surface – the wider the ice circle, the deeper will be the freeze.
The most common technique of cryotherapy is spraying liquid nitrogen directly onto the lesion via a fine spray. The following factors influence how much tissue is frozen and at what depth:
As you can see, technique is important. It looks simple but the technique does involve attention to detail.
Cryotherapy is used to treat a huge variety of skin lesions including some types of skin cancer. The most common lesions treated are:
The procedure is normally well tolerated. However, deeper freezes required for large or malignant lesions may have significant side effects
Different types of skin cancer cells are killed at different temperatures.
Melanocytes are the pigment-carrying skin cells. Unfortunately, melanocytes are killed at lower temperatures than most other types of skin cell including all the types of cell which are being targeted during cryotherapy. Therefore, pale patches are common after cryotherapy.
Often performed during a skin check.
Shave Biopsy is probably the most commonly performed type of skin biopsy to establish a diagnosis of skin cancer. No sutures are involved, and it generally gives good pathology samples for most superficial skin lesions.
A type of razor- blade cuts through the upper layer of skin that approximates to the the epidermis and upper dermis.
A shave gives a better sample for the pathologist but does not allow for the “feel” of a curettage procedure (during curettage, the demarcation point between healthy and cancerous skin can be felt). So the decision to curet or shave a lesion will depend on the clinical certainty of the diagnosis using dermatoscopy.
The cosmetic outcome of a superficial shave is normally good – similar to the outcome of a curettage procedure.
Local anaesthetic is used before the blade is applied. The shave instrument is a disposable sterile surgical blade that allows skin to be cut through horizontally.
There are a range of benign lesions that may be removed with a shave excision, although some types of lesion are more likely to grow back than others. Curettage (with cautery) may be a better option for some lesions such as pyogenic granuloma.
Another type of shave biopsy is a deep shave biopsy – also called a saucerisation biopsy. This type of shave excision takes a deeper out a deeper layer of skin (well into the dermis) – and is therefore used when a deeper layer of skin will be required by the pathologist.
A saucerisation biopsy will leave a more pronounced scar than a superficial shave. A saucerisation biopsy is an alternative to formal surgical excision in the management of some pigmented skin lesions. Australian and International Guidelines do emphasise that formal surgical excision is generally the better option for initial sampling of a melanoma. There are situations where a shave sample of a possible melanoma might be considered because guidelines cannot cover every scenario.
As with a formal surgical excision, risks are infection, bleeding and scarring.
The degree of scarring, will depend on how deep the shave is performed, and factors such as age, location and physical activities. A saucerisation biopsy on the back of a physically active male is like take weeks to heal and is likely to scar significantly. A deep shave taken over the shoulders or front of the chest are most likely to cause a hypertrophic or keloid scar.
Shave excision below the knee in older people may take a long time to heal.
The main way of both sampling and treating a superficial skin cancer at the same time.
In dermatological surgery, Curettage is a method of removing lesions using a curet. Curettage is a widely used method of both treating and sampling superficial skin cancers with minimal scarring.
A curet is a sterile surgical instrument with a curved ending that allows a lesion to be scraped out. The cosmetic outcome is similar to that of a shave excision.
A curet allows a lesion to be scraped out by “feel” whereas a shave involves a flat cut along the base of the lesion.
Curettage is normally combined with Cautery and this is called “Curettage & Cautery”
Curettage is used for two purposes:
Curettage & Cautery is generally considered a low-risk procedure. The risks, though small, are the same as the risks of a formal surgical excision.
It is not always possible to know in advance how deep the curettage procedure will need to be. Deeper procedures will leave a more prominent scar. Smaller and/or superficial curettage procedures typically leave small scars.
Used to Apple Core a lesion.
A Punch biopsy is a great way to take a sample of a large lesion or unusual skin rash. A surgical instrument called a punch biopsy is used to remove a “core” of skin. Local anaesthetic is injected before the punch instrument is applied.
Punch biopsies vary in diameter from 2mm to 8mm. A 2mm is suitable perhaps for an eyelid whereas a 3-4mm punch or more is typically preferred for skin cancer biopsy purposes. A complete small skin lesion (including a rim of normal skin called the margin) may be removed with an 8mm punch.
No suture is necessary for the smallest punch biopsies. An 8mm punch biopsy will require 2 to 3 sutures. The most common size used is a 4-5mm punch biopsy which will usually require a single suture.
Typical reasons to perform a punch biopsy might be:
What are the risks of a punch biopsy?
Punch biopsy is generally considered a low-risk procedure.
There is a risk of bleeding, and damage to underlying structures is a recognised but uncommon complication (e.g. nerve damage). These risks are small to extremely small.
‘Cut and Stitch’ is required for any type of deep skin cancer.
A formal surgical excision is commonly performed in the skin cancer clinic as a way to both remove and treat a suspected lesion. Surgical Excision provides the best possible full-thickness skin sample for the pathologist to work with. This method is usually the best way to diagnose a suspected melanoma.
There are three main issues to consider:
The cutting of a a standard formal surgical excision is in a diamond shape. The procedure is sterile procedure & performed under local anaesthetic.
Flaps and grafts require a higher level of surgical training and are carried out by some skin cancer doctors, some Dermatologists, and of course plastic surgeons.
The question is really – what is the length of the scar? For a standard excision, imagine a circle drawn around the lesion. This circle must include a margin of normal skin either side of the lesion (the margin is usually 2-4mm but may be considerably greater). Now measure the width (diameter) across this circle and multiple this figure by 3 to get the approximate length of scar.
For example, consider a lesion measuring 8mm across that is removed with margins of an additional 2mm either side. The total width of the skin to be removed is 8mm (the lesion itself) + 2mm (margin of skin one side) + 2mm (margin of skin the other side) = a diameter of 12mm across. The length of the scar will be approximately 3 x the diameter. In this example, 3 x 12mm = approximately a 36mm length scar.
So you can see how a small lesion (8mm) leaves a much longer scar (around 3.5cm). This often comes as a surprise.
The scar may be a little shorter or longer depending on factors such as the movement of the skin.
There are risks to everything medical (almost) – and doing nothing is rarely an option with skin cancer. However, there may other surgical or topical treatments that are appropriate, and these options should be discussed. However, it’s usually pretty clear when a skin cancer is is best removed in its entirety.
A rough guide only (it is an individual decision depending on factors such as ease of closure, age of patient & how physical the person will be afterwards)
The face heals quickly and early removal of sutures will reduce risk of suture scars. The lower legs need the longest time before removal of suture because of the tension of the skin in that area and the movement to be expected with day to day activities.
The wound is only at 10% of final strength at 2 weeks, and 50% at 4 weeks. Healing wounds are delicate and need to be respected!
The key is to keep it covered until the removal of the sutures. It’s proven that moist wounds heal faster and better than dry wounds. The old adage of “getting air to the wound” is not appropriate! Typically, a clean dry dressing may be put on and replaced when required until suture removal.
It’s a good idea not to over-do the physical activities soon after the procedure, particularly for complex closures or excisions on the limbs or back. Come to an agreement with your doctor and stick to it!
After the sutures are removed, it is proven that “taping” the wound for up to 3 months reduces scarring. This is particularly important in areas where the scars tend to spread over time eg the back. How do you tape the wound? Just use steristrips or fixomull tape from the pharmacy, cut to size and put over the wound. Fixomull is a breathable fabric that sticks to skin that you can buy from a pharmacy.
1st published 31/10/18
Dr Richard Beatty