After proper anesthesia, liquid nitrogen is sprayed over the entire affected surfaces with depth of destruction controlled by the operator.
This results in not only the removal of advanced precancers but also early precancers and those that are barely visualized or have not yet emerged. Actinic keratoses "recurrence rates" are much lower than after use of chemical peel or 5-Florouracil (5-FU).
Beyond its superior efficacy other advantages include elimination of incidental lentigos, seborrheic keratoses, verruca, etc. the cosmetic results are also remarkable with virtual disappearance of dyschromia and fine wrinkles.
In a follow up study of 351 patients followed anywhere from six months to over five years post cryopeeling the incidence of new or old actinic keratoses reemerging was less than 14 percent over one-year period and less than 27 percent over a three-year period. This is in contrast to a recent study in which after one year there was an incidence of 25 percent emergents of new or recurrent actinic keratoses in 5-FU and TCA chemically peeled patients. Furthermore, at the end of three years, the incidence of recurrence of new actinic keratoses was 75 percent with the TCA peels and 55 percent with 5-FU. Thirtyone thousand (31,000) actinic keratoses were removed. The total number of squamous cell carcinomas detected over the treatment period was 26. Although, not all patients were followed-up, these numbers are approximately one-third of the predicted number of squamous cell carcinomas that should appear on a yearly basis! This comparison data was taken from one of the most conservative estimates of squamous cell carcinomas evolving from untreated actinic keratoses.