347P - Relationship between modified surgical margin and prognosis of cutaneous squamous cell carcinoma

Background

Controversy exists regarding the optimal margin of surgical excision for cutaneous squamous cell carcinoma (cSCC). Japanese clinical practice guidelines for skin cancer (second edition) recommend an excision with a 4–6-mm clinical margin for low-risk cSCC and >6-mm clinical margin for high-risk cSCC. However, it is difficult to follow this guideline for all cSCCs because high-risk cSCCs frequently occur on the face or in older patients. The purpose of this study was to investigate the correlation between surgical margin and prognosis in patients with cSCC.

Methods

Patients with cSCC who underwent surgical excision of the primary site between 2011 and 2019 at Saitama Medical University International Medical Center were included in this retrospective observational study. Patients were divided into two groups: group A (standard surgery with guideline-recommended margin) and group B (modified surgery with narrow margin). Overall survival (OS), relapse-free survival (RFS), local recurrence-free survival (LRFS), regional metastasis-free survival (RMFS), and distant metastasis-free survival (DMFS) were compared between the two groups.

Results

A total of 107 patients with cSCC were included in this study: 39 in group A and 68 in group B. There were no significant differences in patient characteristics such as sex, tumor border, and risk factors; age and tumor size differed between groups. There were no statistically significant differences in OS (p=.470), LRFS (p=.631), RMFS (p=.502), and DMFS (p=.475) between the two groups. However, RFS was significantly lower in group A than in group B (p=.049).

Conclusions

This study did not reveal a significant impact of clinical margin on OS in patients with cSCC. Although this conclusion may have been limited by selection bias, excision with narrower margins than those suggested by current guidelines may be appropriate.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.