title: Selective sentinel lymph node dissection for melanoma: importance of harvesting nodes with lower radioactive counts without the need for blue dye.
abstract: BACKGROUND
  Determining how many sentinel lymph nodes (SLNs) should be removed for melanoma is important. The purpose of this study is to determine the frequency at which nodes that are less radioactive than the "hottest" node (which is negative) are positive for melanoma, how low of a radioactivity should warrant harvest, and if isosulfan blue is necessary.
  
  
  METHODS
  We reviewed 1,152 melanoma patients who underwent lymphoscintigraphy with technetium, with or without blue dye, and SLN dissection from 1996 to 2008. SLNs with radioactivity ≥10% of the "hottest" SLN, all blue nodes, and all suspicious nodes were removed and analyzed. The miss rate was calculated as the proportion of node positive cases in which the "hottest" SLN was negative.
  
  
  RESULTS
  SLNs were identified in 1,520 nodal basins in 1,152 patients. SLN micrometastases were detected in 218 basins (14%) in 204 patients (18%). In 16% of SLN-positive patients (33/204 patients), the positive SLN was found to have a lower radioactive count than the "hottest" SLN, which was negative. In 21 of these cases, the positive SLNs had radioactivity ≤50% of the "hottest" SLN. The 10% rule significantly reduced the miss rate to 2.5% compared with removal of only the "hottest" SLN (miss rate = 16%). Also, blue dye did not significantly decrease the miss rate compared with radiocolloid alone using the 10% rule.
  
  
  CONCLUSIONS
  To decrease the miss rate, all SLNs with ≥10% of the ex vivo radioactivity of the "hottest" SLN should be removed and blue dye is not essential.
authors.affiliation: Department of Surgery, University of California, San Francisco, CA, USA.
authors.forename: Liang-Chih
authors.initials: LC
authors.lastname: Liu
authors.forename: Brian M
authors.initials: BM
authors.lastname: Parrett
authors.forename: Tyler
authors.initials: T
authors.lastname: Jenkins
authors.forename: Wayne
authors.initials: W
authors.lastname: Lee
authors.forename: Eugene
authors.initials: E
authors.lastname: Morita
authors.forename: Patrick
authors.initials: P
authors.lastname: Treseler
authors.forename: Laura
authors.initials: L
authors.lastname: Huang
authors.forename: Suresh
authors.initials: S
authors.lastname: Thummala
authors.forename: Robert E
authors.initials: RE
authors.lastname: Allen
authors.forename: Mohammed
authors.initials: M
authors.lastname: Kashani-Sabet
authors.forename: Stanley P L
authors.initials: SP
authors.lastname: Leong
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004396:Coloring Agents; D005188:False Negative Reactions; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis; D061305:Lymphoscintigraphy; D008297:Male; D008545:Melanoma / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D008875:Middle Aged; D061206:Neoplasm Micrometastasis; D011379:Prognosis; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012394:Rosaniline Dyes; D021701:Sentinel Lymph Node Biopsy; D012878:Skin Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary* / Q000601:surgery; D013671:Technetium Tc 99m Sulfur Colloid; D055815:Young Adult
chemical_list: D004396:Coloring Agents; D019275:Radiopharmaceuticals; D012394:Rosaniline Dyes; C025484:iso-sulfan blue; D013671:Technetium Tc 99m Sulfur Colloid