The Pattern Analysis of Subclinical Invasion of Eyelid Basal Cell Carcinoma Using Mohs Micrographic Surgery

Jeong, J T; Seo, S H; McCall, M W; Kim, I H

Abstract

BACKGROUND: Mohs micrographic surgery(MMS) is frequently used to remove basal cell carcinoma(BCC). BCC involving the eyelid requires a minimal amount of normal tissue excision for the preservation of normal eyelid function and aesthetics. Several authors have reported the microscopic and clinical extent of BCC using MMS. However, no previous study for the patterns of subclinical invasion of BCC is available.
OBJECTIVE
To evaluate the patterns of subclinical invasion of basal cell carcinoma using Mohs micrographic surgery.
METHODS
Review of medical records of patients who underwent Mohs micrographic excision of eyelid BCC between 1993 and 1998 was done. Data analysis was conducted on histologic tumor type, anatomic location, size of tumor, type of Mohs excision for clear margin, pattern of Mohs excision, number of Mohs excisions that were required for clear margin
RESULTS
One hundred three patients(56 men, 47 women) with basal cell carcinoma were enrolled. The most frequent site of involvement is lower eyelid(77/103, 74.7 %). We classified Mohs micrographic excision for clear margin into 3 types according to the direction of positive margin in excised tissue by each stage. Type I removal(>three sides positive at each Mohs excision or first stage of Mohs excision) are the most common (56/103-54.4 %). Type II removal (one side positive at each Mohs stage) are 45/103 (43.7%) and type III (two sides positive at each Mohs stage) and mixed type removal are 2/103(1.9%). Using this removal type analysis, we classified the pattern of Mohs excision(Pattern I-III). Of 58 cases except for Mohs stage B, 47cases have a irregular subclinical infiltration pattern(Pattern II, III and mixed). Invasive type of BCC required the more Mohs stages and sections when compared with noninvasive type.
CONCLUSIONS
Our data showed basal cell carcinomas have a highly irregular infiltration pattern. We also found that pattern analysis of subclinical invasion of basal cell carcinomas is useful in planning surgery because it permits reduction of operative measures to a minimum.