Psoriasis is a common chronic autoimmune skin condition. Patients who have psoriasis have increased rates of depression and cardiovascular disease. Additionally, up to one third of patients who have psoriasis will suffer from psoriatic arthritis. A recent study in JAMA Dermatology investigated the association between cancer and psoriasis. It is hypothesized the chronic inflammation that plays a role in the development of psoriasis may also increase an individuals’ risk for cancer. Furthermore, it is theorized some of the treatments for psoriasis may increase the risk for development of cancer. The systematic review and meta-analysis included 58 observational studies and found the overall risk of developing cancer was significantly elevated in people with psoriasis.
In addition to the elevated risk for the development of cancer, the risk of cancer mortality was found to be elevated in those with severe psoriasis in this study. Severe psoriasis was categorized as individuals who received systemic treatment for their psoriasis or who had been hospitalized for their psoriasis. Patients with all severities of psoriasis were found to have an elevated incidence for lymphoma, keratinocyte, esophageal, liver and pancreatic cancers. For patients with severe psoriasis, they were found to have an increased risk of mortality from esophageal, liver and pancreatic cancer.
Although preliminary studies of the use of immunomodulatory agents have suggested little to no increased risk of cancer incidence in patients with psoriasis receiving these therapies, the authors of this study recommend greater follow up and increased power of these studies to further examine the risk. Of note is the increased prevalence of known cancer risk factors in people with psoriasis such as smoking, excessive alcohol consumption and obesity. The potential role of these lifestyle factors is strengthened by the increased risk of cancers, such as esophageal and liver cancer, associated with these risk factors . One of the limitations of this study include these potential confounders of the cancer risk factors. The authors recommend that given the evidence of this study, guidelines for lifestyle behavior changes might be considered in psoriasis patients to help attenuate some of the cancer risk.