To many, summer is all about the sun, sea and beaches giving rise to the annual chance for a tanned skin tone. However, it is seldom realized that the bronze skin could be lethal! The bronze tone is due to the melanin production post-suntan. In other words, the skin has been exposed and is impacted by the harmful UV rays, and so as a result, the chance of developing skin cancer has increased.
In the past, skin cancer occurred more commonly with Caucasians in the Western countries. Recently, there has been a rapid rise in the number of cases within Hong Kong. According to the Hospital Authority, the number of new skin cancer cases increased from 503 in the year 2000 to 1,063 in 2016. Despite this dramatic increase, this almost went by unnoticed. Currently, this disease ranks seven in Hong Kong's top ten common cancers. Don't you think it's time for us to take this more seriously?
Excessive sun exposure increases the risk of skin cancer
UV rays are released from the sun can generally be categorized into three types: UVA, UVB and UVC. Although UVC is absorbed by the Earth's atmosphere, UVA and small amounts of UVB manages to pass through which then causes skin cancer. UVA is the main culprit for aging skin and formation of wrinkles whereas UVB predominantly causes rashes and sunburns.
There are quite a few misunderstandings regarding skin cancer. One common misunderstanding is that excessive sun exposure is equivalent to the accumulated result of sunbathing. The truth is that even if the skin gets sunburnt once and produces blister, the chances of developing skin cancer in the future would have increased.
Another misunderstanding is that only the sun releases UV rays. In reality, indoor fluorescent lamps do as well. Currently there are no guidelines regarding the safety usage of fluorescent lamps. The more we use them, the greater the likelihood in developing skin cancer.
So how do we prevent skin cancer?
Sunscreen is the most effective method. When buying sunscreens, we should pay attention to the SPF and PA levels which represent the amount of protection against UVB and UVA respectively. We should be mindful that the scale of sun protection isn't linear. For example, SPF15 blocks 93% of UVB and SPF30 filters out 97% of UVB, this difference is minimal. Be advised that an SPF30 sunscreen is good enough for general outdoor activities. If you are going to be at the beach for an extended period of time, you should consider an SPF50 sunscreen and apply it to your whole body every 2 hours, or every hour if you’re playing water sports or sweating in great amounts.
Also, some may presume that having darker skin with more melanin means that it would be a good protector of UV rays therefore then assume darker skinned people wouldn't require sunscreen. Although it's true that melanin can prevent UV rays, but this is only possible to some extent. Any skin type and tone will still have the chance in developing skin cancer after having excessive exposure to the sun. To those who have a light skin tone and tend to get sunburn rather than suntan after basking in the sun, there is a higher risk of developing skin cancer.
Regular checks as a precaution
Apart from using sunscreens, regular precautionary check-ups for our skin is crucial. There are two types of skin cancer: non-melanoma and melanoma skin cancer. Over 90% of cases are non-melanoma and the most affected body parts include the head, neck, nose, arms and areas exposed to the sun. For melanoma skin cancer, over half of the cases were found in legs.
The early stage of skin cancer is commonly marked by new small moles in the skin which can easily be overlooked and thus, the golden period for treatment is often missed out. This is extremely unfortunate as during this period, skin cancer could be radically cured with surgery or radiotherapy. For cases in stage 3 or 4 where surgery is not possible, patients would be given a test to see if the cancer has genetically mutated. If yes, targeted therapy would be considered; if the results are negative, then the emerging immunotherapy would be an option to help extend the patients’ lifespan.
Dr. Choy Tim Shing, Specialist in Clinical Oncology