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Lmax and imiquimod 3.75% in daily clinical practice
1Department of Dermatology, Monklands Hospital, Airdrie, Lanarkshire, UK.
Background:
Lmax, the maximum lesion count during treatment, is a new concept for evaluating the efficacy of field-directed treatments for actinic keratosis (AK) against clinical and subclinical lesions. Imiquimod 3.75% is a field-directed AK treatment, which can detect and clear clinical and subclinical lesions across an entire sun-exposed field such as the full face or balding scalp.
Objectives:
To evaluate the importance of integrating Lmax into daily clinical practice by describing the clinical features and outcomes obtained in the first 10 patients who were treated with imiquimod 3.75% in a UK dermatology department.
Methods:
Ten AK patients were treated with imiquimod 3.75% in two 2-week treatment cycles separated by a 2-week treatment-free interval. Lesions were counted before, during and 2 months after treatment was completed. Patients compared the imiquimod 3.75% regimen with their previous AK therapies in terms of treatment duration and side-effect profile.
Results:
All 10 patients in this cohort had used two or more prior AK treatments including 5-flurouracil, diclofenac, imiquimod 5% and photodynamic therapy. The patients had a median of 10 AK lesions on clinical presentation and a median Lmax of 14. The median lesion count was zero 2 months after treatment was completed. All patients thought that imiquimod 3.75% was easy-to-use and that the duration of treatment was better than that of previous AK therapies. Seven of the patients considered the side-effect profile of imiquimod 3.75% to be better than that of their prior AK treatments.
Conclusions:
Imiquimod 3.75% in daily clinical practice enables dermatologists to detect and clear clinical and subclinical AK lesions across a large sun-exposed area. Patients generally find imiquimod 3.75% easy-to-use with a better side-effect profile than other AK treatments.

