Sentinel Node Biopsy in Melanoma: An Update Estado actual del ganglio centinela en el melanoma

Sentinel node (SN) biopsy, a procedure based on the identification and histologic examination of the first lymph node on the direct drainage pathway from the tumor, is widely used to stage melanoma and other, non-cutaneous, malignancies, such as breast cancer. The technique was introduced by Morton et al1 in 1992 as a new standard in the surgical treatment of localized melanoma. Several later studies confirmed that in most cases in which SN biopsy was negative the other nodes in the same drainage basin were also free of metastatic disease, implying that complete lymphadenectomy could be reserved for use only when the SN was found to be tumor-positive.2--4 This approach to lymph node excision, based on the state of the SN, is known as selective lymphadenectomy. The same technique is currently being introduced into the management of other types of skin tumors, such as high-risk squamous cell and Merkel cell carcinomas.5,6 However, the use of selective lymphadenectomy in the treatment of melanoma is still controversial. The influence of this procedure on survival rates amongmelanoma patients was studied in a randomized, prospective, multicenter study by Morton et al7 published in 2006. Since both the critics and the advocates of selective lymphadenectomy often refer to the design, results, and interpretation of this study, we consider it useful to review the basic issues involved. In an article published in 2007 in the Evidence-Based Dermatology section of the Archives of Dermatology, Urbà González made a case that this study by Morton et al was an example of how the opinion held by a group of researchers concerning the