[An initial experience of the use of sentinel lymph node biopsy in squamous cell cancer of the vulva].

OBJECTIVE: To evaluate the feasibility of sentinel lymph node biopsy (SLNB) in patients with vulvar cancer. METHODS: Twenty-one patients with vulvar squamous cancer undergoing radical surgery admitted in Cancer Hospital of Chinese Academy of Medical Sciences from Oct. 2004 to Apr. 2008, were enrolled in the study. SLNB procedure was performed with blue dye alone in the first eleven patients, while the later ten patients, a combination procedure with radioactive tracer and blue dye was used to detect sentinel lymph node (SLN). All resected nodes were submitted to the pathological examination, which was considered as the gold standard to determine the efficacy of SLNB. The complications related to SLNB were also observed during the study. RESULTS: The sentinel node was identified in 20 patients (95%), included 8 cases with unilateral SLNs and 12 cases with bilateral SLN. A total of 83 SLN were identified with a mean number of 4.2 per patient (range, 1 - 9) or 2.6 per groin (range, 1 - 6). Difference between the mean number of SLN (4.4 per patient, 2.5 per groin) identified by blue dye or by combined procedure (3.9 per patient, 2.7 per groin) was not statistically significant (t = 0.459, P = 0.652;t = -0.421, P = 0.717). Twenty patients were detected to positively superficial inguinal SLN and one of them also positively bilateral deep femoral SLN, 8 (10 groins) of them were detected positively nodal metastases. Among of eight patients, 7 (9 groins) of them were detected more than one SLN involved, while 1 of them were detected false-negative node involved. The false negative rate of was 10% (1/10), negative predictive value was 96% (22/23). No complications were attributed to the study. CONCLUSIONS: SLNB procedure in vulvar cancer is feasible and safe. SLN identification appears to be highly accurate for detecting metastases in the ipsilateral inguinal lymphatic basins.