Immunocryosurgery for non-superficial basal cell carcinomas ≤ 20 mm in maximal diameter: Five-year follow-up

To report the five-year follow up results of a prior prospective clinical trial (NCT01212562) on immunocryosurgery for the treatment of non-superficial basal cell carcinoma (BCC) ≤20 mm in diameter.

Immunocryosurgery consists of five weeks daily 5% imiquimod cream and a cryosurgery session on day fourteen. This combination cleared 95 ± 2% of BCCs at the eighteen month follow up. Herein, we present the results of the five year follow-up or per last available information of the aforementioned cohort. The primary study outcome was treatment failure (non-complete response or relapse); failure rates were calculated per intention to treat and per protocol.

Data for at least five years after initial treatment were available for 55% of the patients (53.4% of per protocol treated tumors) as actualized up to 31th July 2016. Age at recruitment was the only significant predictor of follow-up availability. Nine treatment failures were documented after one immunocryosurgery cycle. The five-year tumor free rate after one immunocryosurgery cycle was 91.4 ± 2.8% and 87.7 ± 3.1% according to per protocol and per intention to treat analysis, respectively. Sex, tumor size or high-risk anatomical localization within the 'H-area' of the face did not affect treatment outcome. With repeat immunocryosurgery cycles only 3 sites were not tumor free at last follow up (effectiveness: 97.1 ± 1.6% per protocol or 93.2 ± 2.3% per intention to treat analysis). Immunocryosurgery is an effective, minimally invasive treatment alternative to surgical modalities for most BCC ≤20 mm in diameter, including those in high risk localizations.