Researchers say that the risk of non-melanoma skin cancers could be increased with alcohol consumption.
Researchers found that every 10-gram increase in alcohol consumed each day was associated with a greater risk of basal cell carcinoma and squamous cell carcinoma, which are the two main types of non-melanoma skin cancers.
Senior study author Dr. Eunyoung Cho - of Brown University in Providence, RI, and Harvard Medical School in Boston, MA - and colleagues say that their findings indicate that alcohol consumption could be an important public health target to reduce the burden of skin cancer worldwide.
The researchers recently reported their results in the British Journal of Dermatology.
According to the American Cancer Society, there are around 5.4 million basal and squamous cell skin cancers diagnosed in the United States every year.
Basal cell skin cancer, or basal cell carcinoma, is by far the most common form of skin cancer, accounting for around 8 in 10 cases. This cancer begins in basal cells situated in the lower part of the epidermis, or the top layer of skin.
Squamous cell skin cancer, or squamous cell carcinoma, accounts for around 2 in 10 skin cancers. This cancer begins in squamous cells in the outer layer of the epidermis.
Alcohol intake and skin cancer
Exposure to ultraviolet radiation from the sun or tanning beds is considered the primary risk factor for basal and squamous cell carcinomas, but previous studies have suggested that lifestyle factors may also play a role.
One such factor is alcohol intake. A 2012 study published in the European Journal of Dermatology, for example, found that drinking alcohol may increase the risk of aggressive basal cell carcinoma. However, other studies have found no such link.
To gain a better understanding of the link between alcohol consumption and basal and squamous cell carcinomas, Dr. Cho and colleagues conducted a systematic review and meta-analysis of 307 studies that previously investigated this association.
The final analysis included 13 case-control and cohort studies, which involved 91,942 cases of basal cell carcinoma and 3,299 cases of squamous cell carcinoma.
The results revealed that for every 10-gram increase in alcohol intake each day (for comparison, a "standard drink" in the U.S. contains 14 grams of alcohol), the risk of basal cell carcinoma increased by 7 percent, while the risk of squamous cell carcinoma increased by 11 percent.
The researchers say that their findings should be "interpreted with caution, due to potential residual confounding." However, they believe that the results could have significant public health implications.
"[...] because alcohol drinking is a prevalent and modifiable behavior, it could serve as an important public health target to reduce the global health burden of NMSC [non-melanoma skin cancer]."