Skin Cancer

The information below is general in nature and should be read as a guide only. It is not definitive medical advice. Dr. Anderson will discuss patient specific requirements based on their medical history and diagnosis during a consultation.

​

Melanoma  

Melanoma is an aggressive skin cancer arising from the pigment cells in the skin (melanocytes). Here in Northland, we have amongst the highest rates of melanoma in the world.  The group most at risk is fair skinned men. In our region, the life-time risk is approximately 10% for this group. 

​

The key risk factors for melanoma are age, skin type, family history and UV exposure. Fair skinned individuals have a ten times higher risk of developing melanoma than dark skinned individuals. However, it is important to be aware that melanoma can affect anyone and any changing pigmented skin lesion should always be checked by a GP or skin specialist.

​

The 5 SunSmart measures recommended by the Cancer Society are designed to minimise UV exposure and therefore cancer risk.

 

1. Slip on protective clothing 

 

Wear densely woven, loose‑fitting clothing that covers as much skin as possible. If you can see light through the fabric, UV can reach the skin.  

​

2. Seek the shade

Stay in shade during peak UV times from 10 am until 3pm. Shade reduces direct UV exposure but does not eliminate reflected UV, so it should be combined with other measures.  

​

3. Slop on broad‑spectrum sunscreen 

Use SPF 50 or 50+ broad‑spectrum sunscreen, applied 20 minutes before going outdoors and reapplied every four hours or after swimming. Sunscreen should be used on all exposed skin. 

​

4.  Slap on a hat 

Choose a wide‑brimmed, bucket, or legionnaire‑style hat that shades the face, ears, neck, and eyes. Caps and visors do not provide adequate UV protection.  

​

5. Wrap on sunglasses 

Wear close‑fitting, wrap‑around sunglasses that meet UV‑protection standards to protect against UV‑related eye damage.  

​

Melanoma typically presents as a new or changing pigmented lesion on the skin. Given the high risk of melanoma in our region, we recommend that any such lesion should be urgently assessed by a professional and biopsied if required.  

 

Surgical Excision 

Once diagnosed, melanomas require treatment with a wide local excision to remove the cancer with a margin of surrounding tissue from 1-2 cm. This is done because melanoma can spread in the small network of channels under the skin called lymphatics and if not adequately excised this can leave cancer cells behind leading to a recurrence. 

​

Sometimes this surgery leaves a large defect that can’t be closed by bringing the skin together (primary closure). In this instance we can employ a local flap to redistribute tension in the soft tissues and achieve closure of the wound. If this is not possible, then we may use a skin graft. This is where a shave of skin is taken from elsewhere on the body (donor site) and fixed into the defect to cover it. Over 5 days, new blood vessels grow into this thin layer of skin or ‘graft’ and re-establish a blood supply. Skin grafts require very careful looking after especially in the first week.

 

Nodal Surgery  

How aggressive a melanoma is can be judged by how thick it is under the microscope. Intermediate (1-4mm) and thick melanomas (>4mm) require both re-excision locally and sampling of the first draining lymph node from the cancer (sentinel lymph node biopsy). Lymph nodes process tissue fluid and are where the lymphatic channels drain to. You can think of them as big filters that sort through all the cells and fluid being brought back from the body. We have lymph nodes all over the body but we have large groups of them at specific locations, namely the groin, armpit and neck. These lymph nodes are the first place that melanoma spreads to. Sentinel node involvement with cancer cells is an important marker of risk and is used as an indicator for extra treatment such as immunotherapy. By injecting a tracer into the melanoma excision site we can localise this first draining lymph node and remove it. This allows the pathologist to then accurately assess if there is any cancer in the lymph node.  

​

For patients who have involved lymph nodes at diagnosis, often staging is required with a whole body scan (PET-CT).  This is usually followed by treatment with immunotherapy and then surgery on the nodes. This can either involve removal of all the nodes (regional lymph node dissection) or removal of the most abnormal node on its own which is called an index node excision. 

 

Non-melanoma skin cancer (NMSC) 

 

Non-melanoma skin cancers are incredibly common in Northland, especially in those with fair skin. Early detection and treatment minimises the surgery required for these cancers. Some early types of NMSC can even be treated with topical therapy alone.  For this reason, it is very important to be aware of your skin and to have any new or concerning lesions investigated promptly. These types of skin cancer can often present as a non-healing ulcer, so any non-healing wound persisting past 6 weeks should be checked out by a professional and biopsied if required. It is also recommended that you should have a routine full skin check every 2 years from the age of 40 or annually if you have had previous skin cancers.  

​

Most NMSC can be managed by surgical excision removing the lesion and a small cuff of surrounding tissue to give a clear margin. This can either be closed in a straight line or with local flaps or grafts to reconstruct a defect after surgery is complete. 

​

As an experienced melanoma surgeon, Dr Anderson provides assessment and management of melanoma and non-melanoma skin cancer. When required, for more advanced cancers, he works with oncology and radiology professionals in the northern region melanoma multidisciplinary meeting to plan appropriate additional treatments such as immunotherapy and radiotherapy.