Validation study of the s classification for melanoma patients with positive sentinel nodes: the Montreal experience.
BACKGROUND
Standard of care is to perform a complete lymph node dissection (CLND) in melanoma patients with positive sentinel lymph nodes (SLNs). However, less than 20% will have metastases in non-SLNs. The S classification was described to predict the non-SLN status, hoping to identify a subset of patients who can be spared the CLND. We tried to validate the feasibility and usefulness of this classification.


METHODS
We performed a retrospective chart review. All melanoma cases between 1996 and 2006 were included, and 359 patients with SLN biopsies were identified. All pathology slides were reviewed with an emphasis on the S classification.


RESULTS
There were 365 SLN biopsies performed. A total of 82 patients (22.8%) had positive SLNs, while 277 patients (77.2%) had negative SLNs. There were 22 patients classified as SI, 18 as SII, 37 as SIII, and 5 were unclassified. On CLND, only 10 patients (12.2%) had positive non-SLNs. None of these were classified as SI while 2 patients (11%) were classified as SII and 8 (22%) as SIII. The S category was found to be a predictor of non-SLN status, and this reached statistical significance (P = 0.044). On univariate analysis, only an increasing Breslow depth and ulceration were predictive of a non-SI status.


CONCLUSIONS
Our results suggest that the S classification is easily feasible and predicts the status of non-SLNs. No patient with SI status was found to have additional non-SLN positive nodes. A larger-scale, prospective trial should be done to confirm these results and possibly spare patients the morbidity of CLND with a positive SLN.
Younan
Rami
R
Department of Surgery, Surgical Oncology Unit, University of Montreal Health Center, Montreal, QC, Canada. rami.j.younan@umontreal.ca
Bougrine
A
A
Watters
K
K
Mahboubi
A
A
Bouchereau-Eyegue
M
M
Loutfi
A
A
Tremblay
F
F
Bouffard
D
D
Belisle
A
A
Leblanc
G
G
Nassif
E
E
Martin
G
G
Patocskai
E
E
Alenezi
M
M
Meterissian
S
S
D002170:Canada; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008545:Melanoma / Q000145:classification* / Q000473:pathology* / Q000601:surgery; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D021701:Sentinel Lymph Node Biopsy