Retrospective analysis of study results show use of the en face freezing technique of tumor excision yields low tumor relapse and guarantees negative surgical margins for patients with basal cell and squamous cell skin carcinomas.

“Mohs micrographic surgery (MMS) is one of the proposed techniques for high-risk basal cell carcinomas and squamous cell carcinoms … However, it is important to have an acceptable alternative to MMS, as this technique can be financially unfeasible and have limited availability,” wrote Ana Carolina Vasconcellos Guedes Otsuka, MD, A.C. Camargo Cancer Center, São Paulo, Brazil, and colleagues. “The intraoperative assessment of surgical margins using ‘en face’ frozen sections…is a possible alternative to MMS,” they explained.

The study included 397 patients with basal cell carcinomas or squamous cell carcinomas, from whom 542 skin carcinomas were excised, at the Skin Cancer Center of A.C. Camargo Cancer Center between January 1, 2013 and December 31, 2013. Of the carcinomas collected, 79.7% were basal cell carcinomas, and mostly from the head and neck (87.8%). Clinical epidemiological, anatomopathological, and treatment data was collected on all the patients, including the result of en face freezing technique and the final anatomopathological result after conventional hisopathological processing in paraffin blocks.

After a mean follow-up duration of of 38 months, en face freezing technique yielded a total tumor recurrence of 1.4% (7 of 542 lesions), with a 0.86% being recurrence of primary tumors and 3.7% being recurrent tumors. In 98% of the lesions, study results showed full agreement between en face evaluation and paraffin processing anatomopathological final examination.

Among the limitations of their study, the authors noted that the most notable was the mean follow-up time of approximately 3 years, while most tumor recurrences occur after the fifth year of treatment.

“The intraoperative ‘en face’ frozen section technique is a fast, safe and reliable technique to ensure tumor-free surgical margins for [basal cell carcinomas] and [squamous cell carcinomas]. The tumor recurrence rate in the present study is acceptable, according to the literature,” concluded Dr Otsuka et al.

Source:

Otsuka ACVG, Bertolli E, de Macedo MP, Pinto CAL, Duprat Neto JP. Intraoperative assessment of surgical margins using "en face" frozen sections in the management of cutaneous carcinomas. An Bras Dermatol. 2022;97(5):583-591. doi:10.1016/j.abd.2021.09.013