We have often observed that patients with a histological diagnosis of skin cancer present for definitive treatment without clinical evidence of residual tumor. In the case of squamous cell carcinoma (SCC), there is a perceived need for more extensive treatment given the small, but real, possibility of metastasis. A second biopsy specimen can be obtained to assess the presence of residual tumor, but this approach was proved unreliable.1 Based on tumor location, these patients are often referred for Mohs micrographic surgery (MMS). Because MMS involves examination of the deep and lateral margins rather than cross-sectional evaluation of the entire biopsy specimen, the status of actual residual tumor at the time of surgery is often not known. We were surprised to find that among patients with SCC who presented for MMS with no clinical evidence of tumor, the vast majority showed no histological evidence of residual tumor on completely sectioned biopsy specimens.
McGovern TW, Grossman D, Fitzgerald D, Glusac EJ, Leffell D. Status of Residual Tumor in Patients With Squamous Cell Carcinoma Referred for Mohs Micrographic Surgery. Arch Dermatol. 1999;135(12):1557-1559. doi:10-1001/pubs.Arch Dermatol.-ISSN-0003-987x-135-12-dlt1299