Histologic Margin Involvement by Cutaneous Basal Cell Carcinoma Stroma: A Retrospective Cohort Study for Residual or Recurrent Carcinoma

Track
Clinical Studies
Abstract

Background

The clinical significance of histologic margin involvement by cutaneous basal cell carcinoma (BCC) stroma has not been previously studied. Pathologists’ reporting as well as clinical management of lesions with this finding are not standardized.  The aim of this study is to determine the incidence of residual BCC in immediate re-excision specimens or recurrence rate in lesions that were not re-excised.

Methods

58 cases of BCC with histologic margins involved by stroma identified from 2016 to 2020 were studied. 50 cases underwent immediate re-excision, and the remaining 8 cases were followed for recurrence for 2+ years. BCCs were classified according to subtype. Margin involvement by tumor stroma was classified as peripheral, deep or both. The presence of residual carcinoma in re-excision specimens or recurrence within 2 years of diagnosis was determined for each case. 

Results

Residual carcinoma was found in 7% (4/50) of re-excision cases. Superficial BCC subtype on original biopsy was associated with presence of residual carcinoma on re-excision (p = 0.01, Fischer’s exact test). Stromal margin involvement on biopsy (peripheral, deep, or both) was not associated with likelihood of residual carcinoma on re-excision (p = 0.13, Fischer’s exact test). In cases that were not re-excised, there were no clinical recurrences (0/8). 

Discussion

Previous studies have reported recurrence rates of 33-41% in basal cell carcinoma cases with positive margins involved by tumoral epithelium.  This study reveals that margin involvement by BCC stroma is rarely associated with residual BCC in re-excision specimens or local recurrence.

Published in: ASDP 61st Annual Meeting

Publisher: The American Society of Dermatopathology
Date of Conference: November 4-10, 2024