A set of novel findings from a group of John Hopkins researchers suggests that patients who have previously experienced non-melanoma-type skin cancer are continuing to be sunburned at the same rate as people who have never experienced skin cancer. The research points to poor use of sun protection, excess sun exposure, and similar skin care practices as being behind this trend.
This particular bit of research was a survey study that questioned 758 people with a history of non-melanoma skin cancer along with 34, 161 people who had no history of skin cancer. Participants were asked about any sun-protective practices, which were defined as how often they used sunscreen when going out on a sunny day for more than an hour, wore long sleeves or wide-brimmed hats, or how often they stayed in the shade when going outside in the sun for over an hour. Sun avoidance was also assessed, which was measured as how often on sunny days participants didn’t go outside. Sunburns were also inquired after in order to determine relative rates.
Among participants with a history of skin cancer, 44.3% reported using shade, 20.5% wore long sleeves, 26.1% wore a wide-brimmed hat, and 53.7% wore sunscreen. By comparison, those without a history of skin cancer the rates were 27%, 7.7%, 10.5%, and 33.1%, respectively. Despite this distinctive difference, however, the rates of sunburn between the two groups remained relatively close, with the skin cancer history group having a 29.7% rate of recent sunburns compared to 40.7% of the non-history group. This difference was described by the authors as “not significant”, which they mean in the sense of size, rather than in the sense of statistical significance.
While it is good to know that those who best understand the skin cancer risk posed by sunburns are employing proper precautions, the fact that these methods don’t seem to be working as well as would be hoped is concerning. The survey was not capable of assessing causes of this trend but there are some theories that were proposed. It is possible, for instance, that people were not employing sun protection methods effectively. Since the data was collected via survey and is subject to all the limitations that entails, it is also possible that people were over reporting how much they actually used sun-protective measures, meaning they didn’t actually protect themselves as much as they claimed. There was also a large difference in size between the non-melanoma skin cancer group and the no history group, and this difference could have distorted the comparison.
Regardless of why the results happened, however, doesn’t change the underlying fact. The John Hopkins researchers found that people with a history of non-melanoma skin cancer are still getting sunburned at a rate comparable to those who have never experienced skin cancer. Whether this means more refined data collection or better patient education is needed, especially in the area of sunscreen application, remains to be determined.
Fischer, A., et. al., sunburn and sun-protective behaviors among adults with and without previous nonmelanoma skin cancer (NMSC): A population-based study, ・ Journal of the American Academy of Dermatology, 2016; http://dx.doi.org/10.1016/j.jaad.2016.02.1236