Interest of frozen section procedure in skin tumors other than melanoma

BACKGROUND

Skin tumors are common. Recommended treatment in most cases is surgery, with margins adapted. Except in the case of simple resection and suture, it is necessary to know the status of the margins before reconstructing the defect. A one-stage technique is possible with frozen section analysis, which gives the surgeon an intraoperative assessment of resection quality. The aim of our work is to study the reliability of the frozen section procedure.

METHOD

A retrospective study included 689 patients who underwent surgery for skin tumor (excluding melanoma) between January 2011 and December 2019 at the University Hospital of Caen, France.

RESULTS

In 639 patients (92.75%), the frozen section analysis found healthy margins. There were 21 cases of discrepancy between the frozen section analysis and final histology. Infiltrating and scleroderma-like basal cell carcinomas showed a significantly higher frequency of affected margins on frozen section analysis (p < 0.001). The tumor size and location played a significant role in the margin status.

CONCLUSION

In our department, the frozen section procedure is the reference examination indicating immediate flap reconstruction. The present study demonstrated its interest and overall reliability. However, it is to be used according to histologic type, size, and location.

Effectiveness of dermoscopy in the demarcation of surgical margins in slow Mohs surgery

There is a need for adjuvant imaging techniques that would allow reducing the number of slow Mohs stages. This study aimed to evaluate the use of dermoscopy in the demarcation of basal cell carcinoma (BCC) surgical margins for slow Mohs surgery. This was a retrospective study over 3 years (2016-2019), including patients with BCC excised using slow Mohs surgery. On the basis of the treatment received, the patients were divided into 2 groups: group 1 (28 BCC) and group 2 (26 BCC). In group 2, BCC margins were demarcated using dermoscopy. A total of 54 patients were enrolled in the study. The number of positive lateral margins was significantly lower in the group where BCC margins were demarcated using dermoscopy (19% vs 53%, P = .012). In this group, the number of Mohs stages needed to achieve complete clearance was significantly lower. However, the mean interval between the first Mohs excision and Mohs clearance was not significantly different between the 2 groups (9 ± 4 vs 12 ± 7 days). In conclusion, preoperative dermoscopy is useful for reducing the number of positive lateral margins and the number of slow Mohs stages in treating BCC especially pigmented tumors.