Treating lentigo maligna with imiquimod 5% cream before conservatively staged excisions results in a median final margin of 2 mm with negative histologic margins, according to results published in JAMA Dermatology.
Without imiquimod, the staged excision of lentigo maligna can often require multiple stages and result in significant cosmetic morbidity.
The researchers performed a retrospective medical record review of patients with biopsy-confirmed lentigo maligna tumors who were treated with imiquimod before undergoing staged excision from June 2004 to January 2012 (n=334).
Participants were treated with off-label imiquimod 5% cream for 5 nights per week during a period of 2 to 3 months. Participants who had an inadequate inflammatory response were also treated with tazarotene 0.1% gel 2 times per week. Participants were then treated with conservatively staged excisions beginning with 2-mm margins.
After a mean follow-up of 5.5 years, there were 12 local recurrences (a rate of 3.9%), similar to reported recurrence rates with standard staged excisions via Mohs surgery or en face permanent sections.
“These results support our opinion that neoadjuvant topical imiquimod allows for the confirmation of a negative histologic margin for [lentigo maligna], with a smaller mean surgical margin requirement with consequential lessened cosmetic penalty associated with the surgery,” the researchers wrote.
Donigan JM, Hyde MA, Goldgar DE, et al. Rate of recurrence of lentigo maligna treated with off-label neoadjuvant topical imiquimod, 5%, cream prior to conservatively staged excision [published online May 30, 2018]. JAMA Dermatol. doi: 10.1001/jamadermatol.2018.0530