Sir:FigureWe would like to respond to Dr. Zitelli and colleagues' comments on the optimal treatment for melanoma of the lentigo maligna subtype. We agree that the treatment goal is clear surgical margins before complex reconstruction. An excision technique and pathologic processing that methodically assesses surgical margins is essential to avoid unnecessary excisions and reduce recurrence risk. The best way to achieve compete excision with histologically negative margins, however, is dependent on multiple factors, including practical issues such as locale of the physician, association with a dermatopathologist, and laboratory workflow. Different methods for tissue processing including permanent or frozen sections can yield acceptable results with low recurrence rates in the right hands with appropriate quality assurance methods. What works best very much depends on the available infrastructure and personnel. Although Dr. Zitelli and colleagues have full confidence in the assessment of melanocytic proliferations using frozen sections, many melanoma experts recognize the limitations of frozen sections and prefer to render a diagnosis based on formalin-fixed paraffin-embedded tissue. A group of experienced dermatopathologists compared permanent and frozen sections and concluded that “en face frozen sections are not suitable for accurate surgical margin assessment of melanocytic lesions.”1 Smith-Zagone and Schwartz report that “the distinction of actinically related atypical melanocytic hyperplasia from malignant melanoma in situ is difficult enough on permanent sections, let alone with the superimposed artifacts of frozen sections,” and conclude that “frozen sectioning of melanocytic lesions should, therefore, be strongly discouraged.”2 Furthermore, immunostaining with melanoma-associated antigen recognized by T cells is not always more accurate than high-quality hematoxylin and eosin staining, as false-positive labeling of nonmelanocytic cells has been documented. Therefore, many Mohs' surgeons choose a staged excision technique with rush permanent sections for melanoma of the lentigo maligna subtype to avoid frozen section pitfalls. In the issue of Archives of Dermatology published in May of 2012, Abdelmalek and colleagues describe a staged excision technique with rush permanent sections in 293 cases, with low recurrence rates.3 If the Mohs' surgery technique is used, it is critical that the Mohs' surgeon have expertise in reading frozen sections of melanoma arising in sun-damaged skin, a high volume of such cases, and a technically excellent laboratory with histologic technicians accredited in immunohistochemistry. Only in these selective situations is the Mohs' technique for melanoma of the lentigo maligna subtype truly accurate as Dr. Zitelli and colleagues state. We respectfully disagree that Mohs' surgery is the most accurate method of treating melanoma of the lentigo maligna subtype. As evidenced in Tables 2 and 3 of our publication,4 there is no agreement even among experts regarding whether Mohs' surgery or staged excision is superior. Irrespective of the differences between Mohs' and staged excision techniques, these two techniques are far superior to standard excision and pathology bread-loaf technique. However, the staged excision technique does not require expertise in Mohs' surgery and can be used by plastic surgeons with a thorough understanding of this melanoma subtype and access to a dermatopathologist experienced in tissue-processing techniques outlined in our publication. Lindsay K. McGuire, M.D. Joseph J. Disa, M.D. Erica H. Lee, M.D. Klaus J. Busam, M.D. Kishwer S. Nehal, M.D. Memorial Sloan-Kettering Cancer Center, New York, N.Y. DISCLOSURE The authors have no financial interest to declare in relation to the content of this communication.