AAD Conference Preview: Topical and Intralesional Therapy

In this feature interview with The Dermatologist, Dr Stacy McMurray discussed her session, “Topical and Intralesional Therapy,” before its presentation at the 2023 AAD Annual Meeting.

Stacy McMurray, MD, FAAD, is an assistant professor in the department of dermatology and a member of the Mohs surgery & reconstruction at the Hospital of the University of Pennsylvania in Philadelphia, PA.

Can you give us a preview of the key points your session will cover?

The session focuses on nonsurgical treatment options for actinic keratosis, and keratinocyte carcinomas in the solid organ transplant population. We will review the pertinent literature regarding the efficacy of the topical treatments, which includes the use of field directed therapies for widespread keratinocytic dysplasia. This is often referred to as field cancerization. Finally, we will examine the current evidence for intralesional therapy of nonmelanoma skin cancer in the immune suppressed population, with a focus primarily on methotrexate and 5-fluorouracil.

How can topical and intralesional therapy aid in the treatment of nonmelanoma skin cancer?

The efficacy of nonsurgical treatments for nonmelanoma skin cancer has been demonstrated in the literature since the 1970s. Nonsurgical treatment options are generally reserved for patients who refuse surgery, or who can’t tolerate a surgical procedure. A 2013 review examined the efficacy and associated cost of common nonsurgical treatment modalities, excluding light-based devices such as PDT. This was in the immunocompetent population, and now solid organ transplant recipients have a markedly increased risk of developing actinic keratosis and nonmelanoma skin cancer when compared with the general population. This is secondary to their long-term immunosuppression and impaired DNA repair mechanisms. Precursor lesions, like actinic keratosis, have an increased risk of progression to malignancy, and a lower likelihood of spontaneous regression.

Now, while surgical treatment is ideal for many nonmelanoma skin cancers, given the pathological margin control, transplant patients often have areas of field cancerization, which is diffuse actinic keratosis and nonmelanoma skin cancer. These necessitate treatment tailored to large anatomical areas. There are few high quality randomized controlled trials for topical and intralesional therapy of keratinocyte carcinomas and actinic keratosis.

The limited evidence for specific regimens in the transplant population presents a therapeutic challenge. The safety profiles and efficacy of the individual treatments may vary when compared with those in the immunocompetent population. This session focuses on nonsurgical treatment options in the immune suppressed population. In addition to the topical and intralesional therapies discussed in the 2013 review, we will also briefly discuss use of photodynamic therapy, or PDT, for both treatment and prevention of nonmelanoma skin cancer. We will also discuss some newer treatment options, notably combination therapy with 5-fluorouracil and calcipotriol or calcipotriene. This combination has demonstrated synergistic effects and has shown a potential role in chemo prevention. It's worth mentioning that all these treatments are considered off-label in the immune suppressed population.

What do you hope your colleagues take away from your session?

The goals of this educational session are to review the best available evidence for nonsurgical treatment options for keratinocyte carcinoma in the solid organ transplant population. Additionally, it’s to emphasize the importance of field directed therapy for widespread disease and for chemo prevention. Finally, it’s to equip physicians with recommended dosing regimens and application and injection techniques that are intended to maximize efficacy and minimize patient discomfort.

Are there any more insights you’d like to share about your session and/or AAD?

There are many factors that may be weighed when considering nonsurgical treatment options for nonmelanoma skin cancer. These include approval by the FDA, efficacy, level of evidence for treatment, patient and physician preferences, cost, side effects, and, of course, expectations regarding patient adherence to treatment. Regardless of the selected treatment, a frank and thorough discussion with the patient regarding the risks and benefits of nonsurgical therapy is critical. These topical and intralesional agents provide a valuable alternative to surgical therapy in the correct setting, or an adjunctive treatment for those patients with field disease. The goals of these therapies are similar to those of immunocompetent patients, to prevent invasive disease and to optimize patient quality of life. We're excited about this session, and we look forward to seeing you all at New Orleans and AAD.

Reference
McMurray S. Topical and intralesional therapy. Presented at: AAD Annual Meeting; March 17–21, 2023; New Orleans, LA.