Organ transplant recipients present unique challenges for skin cancer care

Atlanta - The treatment and management of skin cancers in organ transplant recipients (OTR) is challenging. Recent breakthrough medications and combination treatment approaches have resulted in more effective therapeutic options for this patient population.

Organ transplant recipients with or without associated predisposing factors are notoriously known for having a much higher risk of developing actinic keratosis (AK) and nonmelanoma skin cancers (NMSC) such as squamous cell carcinoma (SCC), due to the immunosuppressive medications that they are required to take.

Unfortunately, it is not uncommon that these patients also develop a “field cancerization” or multiple and confluent AKs particularly on sun-exposed skin regions, making treatment choices difficult.

“Field cancerization is a relatively new concept in transplant dermatology,” says Fiona O’Reilly Zwald, M.D., department of dermatology, Emory Health Care, Atlanta. She spoke at the annual meeting of the American Society of Dermatologic Surgery. “Many dermatologists, particularly in the private sector, may be surprised by the amount of tumor load and AKs that they see in OTR patients. Outlining the new clinical paradigms can be very helpful for clinicians in optimally treating their high-risk patients.”

Topical agents such as diclofenac, 5-fluorouracil (5-FU) and imiquimod are all readily used to treat singular lesions as well as field disease, Dr. Zwald says, albeit with varying therapeutic success.

Novel therapeutic

Ingenol mebutate (Picato gel, Leo Pharma) is one new addition to the armamentarium that is proving to be very useful in the treatment of AKs. Though this agent has not been studied yet in OTRs, Dr. Zwald says the medication is a significant breakthrough in terms of efficacy and efficiency of AK treatment.

Available in two different strengths (0.015 percent for face and scalp, and 0.05 percent for other body regions), ingenol mebutate needs only to be applied for three to five days, in contrast to the eight to 12 week protocol with agents such as imiquimod.

The results one can achieve with ingenol mebutate are excellent and due to the significantly shorter treatment phase, Dr. Zwald says. Compliance to the medication becomes less of an issue, which may translate into improved treatment outcomes.

Tailoring topicals

“Regardless of the topical agent used, one should tailor topical treatment choices to the individual patient and their expectations, because each patient may have a different degree of inflammatory response to the agents used,” Dr. Zwald says.

More invasive and aggressive lesions such as in situ SCC can be treated with more aggressive therapeutic measures, such as photodynamic therapy (PDT) used alone or in combination with medications like capecitabine, an orally administered therapeutic agent, Dr. Zwald says.

PDT, when used in combination with oral and/or topical agents, can be very useful and can be viewed as one of the most effective treatment approaches in patients with field disease, she says. Any lesion that persists despite such topical regimens requires an immediate skin biopsy to rule out invasive SCC.

“Combining both treatments at once may elicit too strong of an inflammatory response in the patient and therefore, I would suggest a combination treatment in cyclic rotation, i.e. a monthly course of PDT treatments for about 3 to 4 months, followed up with topical and/or oral therapy for 4 to 6 weeks, if necessary. Such combination treatments have been shown to help clear the field cancerization significantly,” Dr. Zwald says.

As many OTR patients will often present with a multitude of AKs, Dr. Zwald will try to treat as many lesions and as broad of any area as possible in one sitting. The remaining more invasive lesions that are recalcitrant to tried therapies can be removed with adjunctive surgical procedures. According to Dr. Zwald, this has become the gold-standard treatment approach for this high-risk patient population.

Multidisciplinary benefits

When considering treatment options in OTR patients with field disease, Dr. Zwald says a multidisciplinary approach between dermatologists and medical oncologists can help improve treatment outcomes, as well as overall patient care.

In addition to clinicians performing more frequent skin cancer screenings and early and frequent skin biopsies of suspected lesions, Dr. Zwald says that patients should have priority access to a transplant dermatology clinic where they can receive much needed patient education and appropriate treatment.

“The role of the dermatologist in managing skin cancer associated with transplant patients involves frequent emphasis on patient education, sun protection and skin cancer screening,” Dr. Zwald says. “Chemo-preventive strategies should be encouraged and tailored to the individual patient. More recent therapies such as PDT and use of capecitabine require long-term prospective studies to determine efficacy. Ongoing collaboration with transplant providers, especially with regard to revision of immunosuppression, is necessary to improve the prognosis in high-risk patients.” DT

Disclosures: Dr. Zwald reports no relevant financial interests.