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Published on: March 25, 2020
Tumor detection after inflammation or fibrosis on Mohs levels
Jillian Macdonald1, Jason R Sneath, Bryce Cowan
1The Ottawa Hospital, Ottawa, Ontario, Canada. jmacd3@dal.ca
Background:
In Mohs micrographic surgery (MMS), many surgeons will take an additional level based solely on the presence of inflammation or fibrosis.
Objective:
To determine the frequency with which this occurs and parameters predicting tumor discovery on successive levels.
Materials And Methods:
A retrospective study was performed on 22,419 cases treated with MMS between 1996 and May 2011. The surgeons reviewed their own slides in cases where tumor was detected after a level was taken for inflammation or fibrosis.
Results:
An additional level was taken for inflammation or fibrosis in 6,233 cases (27.8%), resulting in tumor detection in 121 cases (1.9%). Additional levels were taken for inflammation in 66.6% and fibrosis in 63.0%. Fourteen collision tumors were identified and were preceded by inflammation in 71% of cases.
Discussion:
Factors that may predict the presence of tumor at subsequent levels include eccentrically placed or shallow first levels failing to completely encompass a previous surgical scar. The presence of dense inflammation may signal an adjacent collision tumor.
Conclusion:
Taking an additional Mohs level when dense inflammation or fibrosis is present may be warranted to ensure complete tumor removal.
