Women who smoke are more likely to suffer from skin cancer, according to a new study.
A team of researchers from the Moffitt Cancer Center in Tampa, Florida discovered that females are at greater risk than men of being diagnosed with a form of the disease that can spread to other organs.
They investigated the link between cigarette smoking and non-melanoma skin cancers, including basal cell carcinoma (BCC) and squamous cell carcinomas (SCC).
The study's 698 participants were asked about their smoking behaviour in terms of years smoked, how many cigarettes per day they smoked, and when those who once smoked quit smoking.
Results revealed that the risk of non-melanoma cancers increased with numbers of cigarettes smoked per day and total number of years smoking.
Although most of the associations were not statistically significant, SCC was found to be twice as likely in women who had smoked for 20 years or more.
SCC has a significant risk of spreading from one organ to another. Developing on the face, predominantly around the lips or ears, it can erode and completely destroy the nose or ear if left untreated. However, this is uncommon in the early stages and most are treated before any spread occurs.
Lead author of the study Dr Dana Rollinson said among men, positive associations with smoking of equal magnitude were observed for BCC and SCC, although none of the associations were statistically significant.
"However, among women, smoking was not associated with BCC, while highly statistically significant associations were observed with SCC. Women with SCC were almost four times more likely than controls to have smoked for 20 or more years."
Researchers said it was not clear why women smokers would be more likely than men to be diagnosed with SCC.
"Observations from the lung cancer literature may provide possible explanations for why smoking was a higher risk factor for SCC in women," said Rollison.
"Female current smokers have higher lung cancer risks than men. Women have been shown to have more active CYP enzyme activity in the lung, where CYP is responsible for metabolising 70 to 80 percent of nicotine. In addition, the up-regulation of CYP by oestrogen may play a role."
Women have been shown to have higher levels of DNA adducts and lower levels of DNA repair in the lung as compared to men, said Rollison.
"Further study is needed to shed more light on the sex-based differences and the role of smoking in non-melanoma skin cancers."