EXPERT ANALYSIS FROM THE AAD SUMMER ACADEMY 2016
BOSTON (FRONTLINE MEDICAL NEWS) – Surgery is the standard of care for most skin cancers, but nonsurgical and adjuvant treatments can be good options for certain skin cancers when surgery would be neither curative nor feasible, according to Anthony Rossi, MD.
“Whether you’re treating a superficial basal cell or superficial squamous cell carcinoma, I think first and foremost, if you’re going to use nonsurgical treatment options, it’s important to have a good biopsy diagnosis,” Dr. Rossi said at the American Academy of Dermatology summer meeting. He also advised that the biopsy capture the entire lesion or a good portion of it to get a good representation. “You don’t want to be surprised by any hiding, high-risk subtypes,” said Dr. Rossi, of the Memorial Sloan Kettering Cancer Center in New York.
Deciding on a nonsurgical treatment option should be based on knowing the patient. For example, know the patient’s concerns about cosmetic deformities, willingness to undergo surgery or not, and ability and willingness to do follow-up self-care.
For superficial basal cell or squamous cell carcinomas in situ and even lentigo maligna in situ not amenable to surgery, imiquimod may be an appropriate treatment. Dr. Rossi said his practice is to use it in an incremental fashion, starting with application five times per week, going to every day if there is no response after 1 to 2 weeks. If the response remains inadequate, he recommended adding a topical retinoid, such as tazarotene, in an effort to increase penetration.
For basal cell carcinomas and squamous cell carcinoma in situ, he uses imiquimod for a total of 6 to 8 weeks, starting from the time of the first reaction. For melanoma in situ, he uses it for more than 60 applications (12 weeks).
To show patients where they should be applying any topical treatment, Dr. Rossi marks the skin, photographs it, and prints out a picture for the patient. Sometimes he uses the patient’s phone to take the picture. For a basal cell or squamous cell carcinoma in situ, he indicates an area at least 5 to 10 mm beyond the margin of the tumor. The area is even larger for melanomas.
Dr. Rossi studies confocal microscopy to detect skin cancers. He uses it before treating a lesion to define the clinical boundaries of the lesion and the boundaries for the nonsurgical treatments, and then he uses it on follow up to look for any recurrences.
New anti-tumor agents
Two oral inhibitors of the sonic hedgehog pathway have been approved within the past 5 years for locally advanced or metastatic basal cell carcinomas. “In the right person, they can be quite beneficial if surgery would leave them with a very large cosmetic deformity or if surgery would be not curative,” Dr. Rossi said. “We’re seeing good results” with acceptable adverse events, specifically taste disturbances, muscle cramps, and hair loss. The first such drug, vismodegib (Erivedge), was approved in 2012, and sonidegib (Odomzo) came on the market about 1 year ago.
Besides oral agents, photodynamic therapy (PDT) with photosensitizers are another option for certain skin tumors. Dr. Rossi said his practice is to keep the treatment room fairly warm to assure good blood flow to the skin and thus good penetration of the drug. Because PDT acts by generating singlet oxygen to kill tumors, good blood flow to the tumor is necessary. To minimize discomfort, he uses pretreatment acetaminophen if patients can take it. After a skin reaction occurs, cool compresses are used, along with dilute acetic acid soaks on crusted or scaling lesions in an effort to prevent infection.
And while these treatments can produce quite angry-looking lesions in the short term, very good healing usually occurs if patients are diligent about wound care. However, Dr. Rossi cautioned that they may need “more hand holding with these nonsurgical treatments, because it is a longer duration of treatment.”
In general for counseling patients on nonsurgical treatments, Dr. Rossi said it is advisable to have good pretreatment and post-treatment plans. “They have to know that they will need to be following up to make sure that there is no recurrence,” he said. “We don’t have clear surgical margins if we’re using these topical treatments, so we have to make sure that they have good, constant follow-up.”
Dr. Rossi reported consulting relationships with Merz, DynaMed, and Novartis.