[Investigation of individualized treatment based on sentinel lymph node biopsy for early-stage vulvar cancer]

To evaluate the feasibility and outcomes of different surgical approaches on the basis of sentinel lymph node biopsy (SLNB) in treating early-stage vulvar cancer, and discuss the proper strategy for individualized treatment.

The medical charts of patients with early-stage vulvar cancer treated in Sun Yat-sen University between January 2004 and December 2013 were retrospectively collected. A total of 74 patients who received sentinel lymph node (SLN) detection in primary surgery were enrolled (average age 55). The surgical approaches contained SLNB, inguinal lymphadenectomy (IL), and extensive vulvectomy. The SLN were examed on intraoperative frozen sections. The treatment protocols, lymphatic metastasis, postoperative recovery condition, recurrence and survival data were collected and analyzed.

At least one SLN was successfully detected in 68 (92%, 68/74) patients. SLN were positive in 21 patients, of whom 12 (group A) underwent bilateral IL, and 9 (group B) received radiotherapy without performed IL. SLN were negative in 47 patients, of whom 26 (group C) underwent bilateral IL and one of them had a non-SLN metastasis, and 21 (group D) were advised to follow-up. The coincidence of pathological results between frozen and paraffin sections was 100%. The sensitivity and specificity of SLNB for diagnosis of lymph node metastasis were 95% and 100%, respectively. A total of 44 complications happened in patients underwent SLNB and IL (group A and C), including 16 poor wound healing, 14 lymphedema, 8 lymphatic fistulas, 3 phlebothrombosis and 3 infections. There were no complications happened in patients underwent SLNB alone (group B and D), among whom the operation time, bleeding amount, and hospital stay were also significantly less than those in patients underwent SLNB and IL. The median follow-up time was 41 months and the 3-year overall survival rate was 85% in the whole series. Recurrences were observed in 11 patients and 9 of them died of the tumor with the median survival time of 15 months. In patients with positive SLN (group A and B), the 3-year overall survival rate was 58% with 8 patients died of the disease, including 4 in group A and 4 in group B. In patients with negative SLN (group C and D), the 3-years overall survival rate was 97% with one patient in group D died of the tumor, and significantly higher than that of patients with positive SLN (P = 0.003). The 3-year overall survival rate was significantly difference. In univariate analysis by log-rank test showed that, neither in patients with nor without SLN metastasis the prognosis differed with respect to surgical approaches (group A vs B, P = 0.709; group C vs D, P = 0.253). Univariate analysis by log-rank test showed that, lymph node metastasis, pathological grade, depth of invasion, and tumor location could significantly affected survival (P < 0.05), whereas age, tumor diameter, and surgical approach didn't (P > 0.05). Multivariate analysis showed that lymph node metastasis (RR = 21.57, 95% CI: 2.68-173.10, P = 0.002) and tumor location (RR = 7.85, 95% CI: 1.79-34.50, P = 0.024) were the independent factors for overall survival.

Lymph node metastasis is an independent prognosis factor for patients with early-stage vulvar cancer. SLNB could accurately diagnose the status of lymph nodes and help to decide subsequent treatment. The omissions of IL in patients with negative SLN avoid surgical morbidity and shorten postoperative recovery period without an increased risk of recurrence.