title: Deep lymph node metastases in the groin significantly affects prognosis, particularly in sentinel node-positive melanoma patients.
abstract: BACKGROUND
  In order to define patients eligible for only a superficial groin dissection or a combined superficial and deep groin dissection, this study aimed to determine the incidence of deep lymph node metastases (LNM) in patients with melanoma metastasized to the groin, to identify patient and melanoma factors that predict deep nodal involvement, and to analyze the impact of deep nodal involvement on survival and recurrence.
  
  
  METHODS
  Patients who underwent a combined superficial (inguinal) and deep (iliac and obturator) complete (CLND) or therapeutic lymph node dissection (TLND) of the groin between 1994 and 2012 were analyzed.
  
  
  RESULTS
  QueryDeep LNM were found in 8 of 62 CLND patients (13 %) and in 21 of 67 TLND patients (31 %). More than three superficial LNM was the only independent predictor for deep LNM in both CLND and TLND patients. The 5-year melanoma-specific survival (MSS) for CLND and TLND patients with deep LNM was 14.3 and 16.6 %, respectively, and was significantly worse (hazard ratio [HR] 3.39, 95 % CI 1.34-8.58, p = 0.010; and HR 2.01, 95 % CI 1.04-3.88, p = 0.039) compared with CLND and TLND patients without deep LNM (5-year MSS: 54.1 and 37.2 %, respectively). Distant recurrence was significantly associated with deep LNM in CLND patients (p = 0.032).
  
  
  CONCLUSIONS
  The present study showed that LNM in the deep area of the groin are fairly common in both CLND and TLND patients and significantly affect prognosis, especially in CLND patients. The number of superficial LNM is the only factor that was found to predict a finding of deep nodal metastases.
authors.affiliation: Department of Surgical Oncology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, PO Box 30.001, 9700, Groningen, The Netherlands.
authors.forename: M G
authors.initials: MG
authors.lastname: Niebling
authors.forename: K P
authors.initials: KP
authors.lastname: Wevers
authors.forename: A J H
authors.initials: AJ
authors.lastname: Suurmeijer
authors.forename: R J
authors.initials: RJ
authors.lastname: van Ginkel
authors.forename: Harald J
authors.initials: HJ
authors.lastname: Hoekstra
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006119:Groin / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008545:Melanoma / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D009367:Neoplasm Staging; D016609:Neoplasms, Second Primary / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D011379:Prognosis; D021701:Sentinel Lymph Node Biopsy; D012878:Skin Neoplasms / Q000401:mortality / Q000556:secondary* / Q000601:surgery; D015996:Survival Rate; D055815:Young Adult