Surgical treatment of vulvar cancer: Impact of tumor-free margin distance on recurrence and survival. A multicentre cohort analysis from the francogyn study group.

OBJECTIVE: In vulvar cancer, it is admitted that tumor-free margin distance is one of the most important element for locoregional control. It is currently recommended to surgically remove the tumor with at least an 8 mm tumor-free margin. The aim of this study was to evaluate the impact of tumor-free margin distance on recurrence and survival in vulvar cancer.

MATERIAL AND METHODS: From 2005 to 2016, 112 patients surgically treated for a vulvar squamous cell cancer were included in a retrospective multicenter study. Overall, disease-free and metastasis-free survivals were analyzed according to tumor-free margin distance.

RESULTS: Patients were divided into three groups: group 1 (margin <3 mm, n = 47); group 2 (margin ≥3 mm to < 8 mm, n = 48) and group 3 (margin ≥8 mm, n = 17). During the study, 26,8% patients developed recurrence (n = 30) after a median of 8 months (1-69). Analysis of 5-year overall survival, as well as disease-free and metastasis-free survivals, did not reveal a difference between groups. We performed a subgroup analysis in patients with a tumor-free margin <8 mm (group 1 and 2). It showed that histological lesions observed closest to the edge of the specimen were more often invasive or in situ carcinoma lesions in group 1 than in group 2, in which VIN lesions were mainly observed at this location. After re-excision, no patients in group 1 and 50% (n = 2) patients in group 2 developed recurrence.

CONCLUSION: This study did not reveal a significant impact of tumor-free margin distance on recurrence and survival in vulvar cancer. Moreover, the benefit of re-excision seems stronger when tumor-free margins are positive or very close (<3 mm), cases in which invasive or in situ lesions are often present closest to the edge of the specimen.