practicaldermatology.com
With a theme of understanding the various options available for treatment of skin cancers and selecting the correct ones for each case, George Martin, MD, Ted Rosen, MD, and Emily Ruiz, MD, MPH, presented “Cutaneous Oncology Update 2025” at the Maui Derm Hawaii 2025 meeting in Maui, Hawaii.
Dr. Rosen noted the “Guidelines of care for the management of actinic keratosis” published in 2021.1
“This is a very old but reliable study,” Dr. Rosen said. “The more actinic keratoses you have, the more likely you are to get a squamous cell.”
The guidelines, Dr. Rosen said, leave much to be desired in the area of cryotherapy.
“There really wasn’t very much in terms of specifics in the guidelines for care,” Dr. Rosen said.
The doctors then discussed 5-Fluorouracil (5-FU) therapy, saying that 5-FU in standard use both looks bad and feels bad.
“Just use it for a week,” Dr. Martin suggested. “You push it to 2 weeks and 4 weeks, you’re not really gaining that much.”
The use of calcipotriol along with 5-FU was suggested as well, though Dr. Martin again cautioned against heavy use.
“If you overdo it … [patients] will call you for pain meds,” he said.
While calcipotriol is not approved for this use, Dr. Martin noted that it can be acquired affordably. It increases TSLP, which enhances the immune response during 5-FU treatments. There is generally no need to compound; equal parts can be mixed by hand and applied.
When using tirbanibulin 1% ointment, the doctors cautioned that patients should be urged to be patient.
“You get a lot of irritation and it peaks at about Day 8,” Dr. Martin said.
Dr. Rosen added that significant improvement can be seen after 15, 30, and 60 days.
“It is very tolerable,” Dr. Rosen said, noting that he is a user himself. He added that some actinic keratoses disappear even during the 5 days of therapy.
Despite the various benefits of tirbanibulin 1%—including a new mechanism of action that is “targeted,” better compliance, strong clearance numbers, and minimal irritation—one drawback is that it is not as efficacious on the scalp as on the face, and it should be avoided—as should 5-FU—during pregnancy.
Photodynamic therapym (PDT) was discussed, with the doctors noting that red or blue light can be used interchangeably when treating actinic keratoses, and that flat panels work best for the trunk while curved panels work best for the face and scalp. For nonmelanoma skin cancer, red light was suggested as a better option because of its deeper penetration.
“If you’re treating nonmelanoma skin cancer, and the cells travel down intrafollicle, you really want to get that light as deep as it will go,” Dr. Martin said.
Dr. Martin highlighted a study led by Edward V. Maytin, MD, PhD, about the evolution of in-office “painless” PDT.2 Dr. Maytin’s protocol involves a “split face” approach, with one side receiving simultaneous 30-, 45-, and 60-minute aminolevulonic acid (ALA) incubation plus blue light, and the other side getting standard 60-minute ALA incubation followed by 1,000 seconds of blue light.
The potential of adding oral vitamin D was discussed as well, as the doctors cited research indicating that PDT does not work well for patients who are deficient in vitamin D.3
“The take home point is: Add vitamin D,” Dr. Martin said.
This year, Dr. Martin said, his protocol will entail pre-treating with 10,000 units of vitamin D3 for 2 weeks prior to painless PDT; applying ALA; immediately turning on blue or red light; and illuminating for 30 minutes.
“If you’re not doing this, you’re really missing the boat,” Dr. Martin said. “You’re compromising your patient from having really good therapies.”
Dr. Martin then discussed imiquimod for continuous immune therapy, applying 3.75% or 5% imiquimod daily for one week with a 2-week “rest period.” He said that, in his experience, this therapy decreases actinic keratoses and reduces nonmelanoma skin cancers while increasing patient satisfaction.
Dr. Rosen cautioned that some patients try to get lower-cost imiquimod online from India or Bangladesh, but that it’s not the same drug.
“Make sure, if you have patients who have a tendency to do that, [that they] get the real thing,” he said.
Dr. Rosen also noted that he avoids using imiquimod on the chest because it can hyperpigment and scar.
The doctors also discussed ALA PDT for squamous cell carcinoma in situ (SCCis). They noted that SCCis on the face responds better to ALA PDT than SCCis on the trunk and extremities. Longer incubation (3 hours or more), they said, produces a higher clearance rate, and smaller lesions respond better to ALA PDT than larger lesions.
Imiquimod also can be used to treat SCCis. Dr. Rosen noted a retrospective study of 49 SCCis cases treated with imiquimod 5%, in which 46 achieved complete clearance.4
The use of acitrecin also was covered, with Dr. Martin noting: “Understand that nonmelanoma skin cancers will recur if you stop this drug.”
The doctors also discussed a trial in progress studying low-dose intralesional cemiplimab vs primary surgery for patients with early-stage cutaneous SCC.
“I can’t wait to see how this all wraps up,” Dr. Martin said.
Dr. Ruiz then presented her top 10 developments and points involving management of advanced nonmelanoma skin cancer in 2024: