Red, inflamed skin is one of the symptoms of psoriasis. Beyond the symptoms of this skin condition, people with psoriasis might also be at risk for other major problems, including cancer.
A recent review of previous studies found that patients with psoriasis had a greater chance of developing cancers that involve the respiratory tract, digestive tract, urinary tract, liver and the skin.
The cancers that were linked to psoriasis have been associated with alcohol drinking and cigarette smoking, according to the researchers. But they said further research on related illnesses and treatments for psoriasis and cancer is needed to get a better understanding of the risk of cancer among psoriasis patients.
C. Pouplard, from the Dermatology Department at Paul Sabatier University in Toulouse, France, led this study investigating whether the chance of cancer was higher among patients with psoriasis compared to the general population.
The researchers looked at 37 previously published studies on psoriasis and cancer between 1980 and January 2012. Two reviewers who were not part of this study selected the previous studies.
For each study selected, the number of psoriasis patients, types of cancer involved and time spent following patients was tracked.
The researchers found a small increased risk of certain cancers in patients who had psoriasis.
The risk for developing urinary tract cancer, non-Hodgkin lymphoma or respiratory tract cancer increased by about 31 percent, 40 percent and 52 percent, respectively, among psoriasis patients compared to patients without the skin condition.
Psoriasis patients were also 90 percent more likely to get liver cancer compared to non-psoriasis patients.
The odds for developing upper aerodigestive tract cancer were three times higher among psoriasis patients.
With regards to certain skin cancers, psoriasis patients were more than twice as likely to develop basal cell carcinoma and five times more likely to develop squamous cell carcinoma. The risk for melanoma did not increase.
The researchers said that more information from ongoing psoriasis registries is needed to better define the risk of cancer in psoriasis.
"In conclusion, psoriasis patients tend to have a small increased risk of some solid cancers, especially those linked to alcohol drinking and cigarette smoking…" the researchers wrote in their report.
The researchers noted a couple of limitations of their investigation, including that they could not gather information on all patients' alcohol usage and whether they smoked.
This study, supported by AbbVie, was published online July 11 in the Journal of the European Academy of Dermatology and Venereology.
The authors were paid consultants of AbbVie, though AbbVie did not take any other role in the study beyond providing financial support.
Some of the authors served as speakers, consultants, investigators and advisors for AbbVie and other institutions related to the investigation.