Cryosurgery Effective Against BCC Relapse, but Further Study Required

Promising findings from an analysis of immunocryosurgery to treat basal cell carcinoma (BCC) that relapsed following surgery—be it standard excision or a Mohs procedure—call for this minimally invasive combination procedure to be further evaluated for use as the definitive treatment for selected facial BCC in the relapsed setting.

Findings were published recently in Current Oncology. To be included in the analysis, patients were required to have had their BCC tumors treated with the standard 5-week immunocryosurgery cycle—defined as daily application of the topical imiquimod for 5 week and a cryosession on day 14. Twenty-seven BCC cases were evaluated.

“In the past decade, we had sporadically treated relapsed BCC with immunocryosurgery, with promising efficacy and adequate tissue-sparing results,” study authors wrote. “In the present retrospective study, based on the compilation of these latter cases, we sought to evaluate the feasibility of immunocryosurgery as performed in a tertiary hospital and an ambulatory clinic.”

Approximately three-fourths (74.1%; n = 20) of the 27 tumors had clearance after 1 treatment cycle with immunocryosurgery. Of the remaining 7 cases that did not demonstrate clearance, a repeat cycle was needed for 2 and 1 patient preferred surgery. Four cases of BCC did not clear even with additional immunocryosurgery cycles. Of these 4 cases, surgery was chosen by 1 patient after a second cycle of immunocryosurgery did not lead to satisfactory clearance; for the 3 other patients who achieved partial remission, this outcome was held constant via occasionally repeating immunocryosurgery (a 6 and 44 months for 1 patient each) or until chemotherapy was initiated with vismodegib at 67 months of follow-up.

The investigators determined immunocryosurgery’s feasibility to induce relapsed BCC tumor clearance to be a mean (SD) of 81.5% (7.5%), and their results show that for the 22 tumors showing complete clearance after immunocryosurgery—20 after 1 cycle, 2 after 2 cycles—there were 3 instances of relapse that occurred at 9, 28, and 50 months. Overall, a mean (SD) of 66.7% (12.4%) remained tumor free by the end of a 5-year follow-up following just immunocryosurgery, with a “respective mean time in sustained tumor control of 101.9 (14.2) months,” the authors noted.

Among the 27 BCC cases, an aggressive histology was seen in 22% (n = 6); among these, the micromorphology was basosquamous in 4 and mixed (basosquamous and micronodular) or keratotic in 1 each.

Considering the tumor relapses and cases of BCC that never cleared, the authors determined overall 5-year efficacy to be a mean (SD) of 60.2% (13.4%) over a mean (SD) progression-free survival of 94.6 (15.1) months.

Following use of a Cox proportional hazards model, only total relapses before immunocryosurgery were shown to be an indicator for tumor progression after the procedure; the other factors investigated as potential predictors were patient age, maximal tumor diameter, average tumor growth rate, and risk factors for relapse before surgery. And treatment effectiveness was equivalent between younger and older (75 years and older) patients.

The investigators note that despite their positive findings on immunocryosurgery, their own previous data show BCC tumor size to be predictive of disease outcomes among patients with tumors larger than 2 cm, with effectiveness of immunocryosurgery sharply dropping when tumors are 2 to 4 cm. Therefore in these patients, “individualized approaches are required.”

Further, they stress the need for “universal predictive ‘tumor-specific factors’ for the response of BCC to treatment, common to all different therapeutic modalities, destructive or not, and on the other, of modality-specific predictive factors of treatment failure.”

Reference

Gaitanis G, Zampeta A, Tsintzou, et al. The feasibility of immunocryosurgery in the treatment of non-superficial, facial basal cell carcinoma that relapsed after standard surgical excision: an experience report from two centers. Curr Oncol. 2022;29(11):8475-8482. doi:10.3390/curroncol29110668