Prognostic value of the number and laterality of metastatic inguinal lymph nodes in vulvar cancer: Revisiting the FIGO staging system

摘要

Objective: Inguinal lymph node (LN) metastasis is an important prognostic factor in vulvar cancer. Our aims were to analyze the prognostic value of LN metastasis with regard to the number of LNs that were involved and their laterality and compare these results with the current FIGO staging system. Methods: A retrospective analysis was performed in a series of 234 individuals who underwent inguinal lymphadenectomy for vulvar squamous cell carcinoma from January 1980 to February 2010. Results: The mean age was 68 years. One hundred seven (45.7%) patients had LN metastasis. Despite the FIGO staging, we did not observe any significant difference in the risk of recurrence or death between patients with 1 positive LN and ≥2 positive LNs. Moreover, there was no difference in outcome between the presence of 1 and 2 positive LNs. On categorizing patients into 3 groups - absence of LN involvement, 1-2 positive LNs, and ≥3 positive LNs - we achieved a significantly better prognostic correlation for progression-free survival, disease-specific survival, and overall survival. Extracapsular spread retained a prognostic role for the risk of recurrence in multivariate analysis. Further, for patients with ≥2 positive LNs, the presence of bilateral positive LNs did not negatively impact the risk of recurrence or death compared with those with unilateral positive LNs. Conclusions: Our data suggest that the prognostic effect of bilateral LNs reflects the worse prognosis of multiple positive LNs. Regarding prognosis, LN involvement should be categorized into 2 groups - 1-2 positive LNs and ≥3 positive LNs.