Surgical Margins for Melanoma in Situ

Murad Alam, MD, MSCI


Journal Watch 

In This Article


This study is a major contribution to the establishment of standard margins for excision of melanoma in situ. The authors work from the reasonable conceit that Mohs surgery with repeated narrow margins can be used to estimate the true extent of a tumor. Operating from this logic, the researchers showed that 9-mm margins (i.e., 3 consecutive 3-mm "stages") were far superior to 6-mm margins (2 consecutive 3-mm stages). The difference in clearance was not only statistically significant but also very clinically significant: The slightly larger margin was associated with a recurrence rate less than one-tenth the rate with the smaller margin. This is a single-center study, and more confirmatory studies may be required to generalize the result and alter the standard of care. On the other hand, the conclusions are intriguing given the extraordinarily large cohort and the high quality of the Mohs practice that produced the data, as evidenced by the extremely low recurrence rate.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.