(LifeWire) - While much has been made of "the heartbreak of psoriasis" (the tagline of a popular 1960s commercial), is there additional heartbreak ahead for people with psoriasis, that is, in the form of an increased risk of lymphoma?
One study suggests that the risk for lymphoma cancer for the psoriasis patient is three times greater than people without psoriasis. Although these results are preliminary and different studies have found conflicting results in terms of the risks of lymphoma among people with psoriasis, many questions are raised for patients and physicians: Is there a link between lymphoma cancer and psoriasis? If there is an increased risk of cancer? Is it due directly to the effects of psoriasis? Is it a complication of psoriasis treatments? Is it the patient's own immune system?
What is Lymphoma?
Lymphoma, a cancer that affects the immune system, occurs when white blood cells develop abnormal features, reproducing rapidly and invading nearby tissues. The two types of lymphoma most often associated with psoriasis are Hodgkin's lymphoma and Cutaneous T-Cell Lymphoma (CTCL), which has been of particular interest to researchers, because the T-cells -- the cancerous immune cells found in CTCL -- play a key role in the chain of events that kick off the skin damage seen in psoriasis. The strongest neoplastic association exists between psoriasis and CTCL. Distinguishing between the skin manifestations of CTCL and those caused by psoriasis can be difficult, because CTCL is often misdiagnosed as psoriasis. In general, CTCL often causes flat or raised orange-red plaques with a wrinkly top. Common locations include the buttocks, skin folds and face. Over time, the patches may grow larger, more irregular in shape and may develop ulcers, sores or bumps on the surface (tumors).How Great is the Risk?
Researchers from the University of Pennsylvania conducted a study published in The Journal for Investigative Dermatology in 2006 and found that people with psoriasis are three times more likely to have lymphoma than people without the skin disorder. The researchers were careful to note, though, that more study is needed to understand the relationship.What May Influence the Risk?
Researchers are very interested in figuring out the answer to this question. Some of the possibilities include:
- Age - Older psoriasis patients (older than age 65) may have a slightly higher risk of developing lymphoma than younger psoriasis patients.
- Severity of the skin disease - People with more severe cases of psoriasis may be at a greater risk of future lymphoma than people with milder cases.
- Types of treatments used - Researchers are examining whether certain treatments, such as Oxsoralen (psoralen)-UVA (PUVA), Rheumatrex or Trexall (methotrexate), Neoral or Sandimmune (cyclosporine) or biologic therapies like Remicade (infliximab), may increase the risk of lymphoma in certain people.
Knowing that there may be a link between lymphoma risk and psoriasis allows you and your doctor to watch for possible signs of lymphoma. For example, any psoriasis plaques with an unusual appearance or location, such as in the groin or around the buttocks, should be reported to your doctor and may need to be biopsied to rule out cancer. If you use immune system-suppressing medications for your psoriasis, such as cyclosporine or methotrexate, or if you have been treated with PUVA, you'll want to watch for changes to your skin. You should ask your doctor to do comprehensive annual skin examinations and talk with your physician about factors that may influence your cancer risk and what you can do to lower that risk.
While awareness of this issue may cause feelings of anxiety or worry, try to let the information empower you to make choices known to reduce cancer risk instead, such as following sun exposure guidelines, maintaining a healthy weight, abstaining from tobacco use and avoiding excessive alcohol.
Gelfand, J.M., et al. "The Risk of Lymphoma in Patients with Psoriasis." The Journal for Investigative Dermatology. 126 (2006) 2194-2201.<http://www.nature.com/jid/journal/v126/n10/pdf/5700410a.pdf>
Kimball A.B., et al. "National Psoriasis Foundation Clinical Consensus on Psoriasis Comorbidities and Recommendations for Screening." Journal of the American Academy of Dermatology. 58.6 (2008): 1031-42.<http://www.mdconsult.com/das/article/body/96404164-25/jorg=journal&source=MI&sp=20676024&sid=712303251/N/644311/1.html?issn=0190-9622> (subscription)
Stern R.S. "Lymphoma Risk in Psoriasis: Results of the PUVA Follow-Up Study." Archives of Dermatology. 142.9 (2006): 1132-1135. <http://archderm.ama-assn.org/cgi/content/full/142/9/1132?ck=nck>