EORTC Updates Sentinel Lymph Node Biopsy Protocol in Melanoma
Posted: Friday, May 31, 2019
For pathologists conducting pathologic evaluation of sentinel lymph nodes for melanoma, the European Organisation for Research and Treatment of Cancer (EORTC) Melanoma Group has released an updated its protocol, in a report published in the European Journal of Cancer. Although the authors noted there is insufficient evidence to change sentinel lymph node biopsyprotocols fundamentally, considering the divergence of histopathologic protocols among physicians, the EORTC provided guidance through recommendations.
“This updated EORTC protocol is expected to clarify and simplify the existing procedures, ensuring a reasonable workload for the laboratory and for the pathologists resulting in cost saving with no loss, and possible increase, in accuracy,” concluded Martin G. Cook, MD, of the Royal Surrey County Hospital, Guildford, United Kingdom, and colleagues.
In proposing changes to the current protocols, the EORTC aimed to reduce the technical workload for pathologists and to make the sentinel lymph node procedure more sustainable in a routine diagnostic setting. Recommendations from the authors include extending the distance between steps according to the short axis dimension of the lymph nodes to optimize both conventional sectioning and staining procedures including immunohistochemistry. The proposed changes also provide guidance on the description of spatial localization of melanoma deposits in a sentinel lymph node biopsy.
According to the authors, the histopathologic features that should be reported are the presence or absence of the metastasis and the intranodal location of the metastasis, including subcapsular, parenchymal, combined, extensive confluent, and extensive multifocal. Other features to be reported are the number of metastatic deposits (1, 2–5, 6–10, 11–20, and > 20), the maximum dimensions of the largest metastasis (indicating its site), and the presence of extracapsular extension and of nevus cells.
Disclosure: The authors reported no conflicts of interest.