From Victor Prieto at MD Anderson-Sentinal lymph nodes in cutaneous melanoma

http://www.archivesofpathology.org/doi/pdf/10.1043/2009-0502-RAR.1

Prieto VG
Sentinal lymph nodes in cutaneous melanoma
Arch Pathol Lab Med. 2010;134:1764–1769

Abstract:
Context.—Within the last 15 years, evaluation of sentinel
lymph nodes (SLNs) has become the most popular method
of early staging of several malignancies, including melanoma. Sentinel lymph nodes are usually examined on
formalin-fixed, paraffin-embedded sections and by routine
histology/immunohistochemistry (research protocols have
used other techniques such as polymerase chain reaction).
Approximately 20% of patients with cutaneous melanoma
have metastasis in the SLN. In most studies, detection of
positive SLN conveys a poorer prognosis for patients with
cutaneous melanoma.
Objective.—To review the morphologic patterns of
melanoma metastasis in the SLN, the differential diagnosis,
and the quantification of tumor burden as a prognostic factor.
Data Sources.—Personal observations and review of the
pertinent literature.
Conclusions.—Evaluation of sentinel lymph nodes is
certainly becoming a widespread technique and most
authors agree on its prognostic power for staging patients
with cutaneous melanoma. Current studies are evaluating
the possible therapeutic value of removal of positive SLNs.