Dr John Chaplin – Head and Neck Surgeon. Auckland. NZ
Skin Cancer of the face, scalp and neck is a very common condition in New Zealand for two main reasons: The first is that a high percentage of the population are orginally immigrants from England, Ireland, Scotland and Wales and have fair skin and the second is the the intensity of the ultraviolet sunlight is among the highest in the world. This combination of factors ensures that we have a rate of 250 skin cancers per 100,000 population per year. The most common are basal cell cancers (BCC) followed by squamous cell cancers (SCC) and then less frequently but more deadly Melanoma and rarely Merkel cell cancers.
The majority of these skin cancers present on the skin of the face and head and neck as these areas are exposed to the sun year round. They tend to be more common in people who have worked outdoors particularly if they have not used protective clothing or sunscreens. They are more common in older people as the sun exposure has a cumulative effect and they are very common in people who have immune deficiency. In this situation the skin cancers tend to be more aggressive also.
SCC and BCC
BCC and SCC of the face, scalp and neck are usually small and and the majority are completely cured by simple excision however, there are some features that make these cancers higher risk. in SCC these features include: depth>2mm, Perineural invasion (PNI), lymphovascular space invasion (LVI), certain anatomical eg. ear, high tumour grade, and established metastases. In BCC these features include: Large size (>20mm), perineural invasion, recurrent BCC, certain anatomical sites eg. embryonic fusion planes. BCC rarely spread to lymph nodes but SCC does this around 5-20% of the time depending on whether the above features are present. The pattern of spread is largely predictable based on the anatomical site of the primary lesion.