Is the Sentinel Lymph Node Biopsy Safe and Accurate After Previous Surgery for Vulvar Squamous Cell Carcinoma? A Systematic Review

: Lymphadenectomy for vulvar carcinoma is characterized by many complications. Studies have demonstrated the diagnostic accuracy of sentinel lymph node biopsy (SLNB) as a valid alternative to lymphadenectomy in the early stages of vulvar squamous cell carcinoma (VSCC). Objective: To evaluate the feasibility, safety, and accuracy, as well as the oncological outcomes of SLNB following scar injection; in addition, to assess the role of a repeat sentinel node procedure in patients with local vulvar recurrence after primary treatment. Materials and Methods: A systematic computerized search of the literature was performed in the main electronic databases (MEDLINE, EMBASE, Web of Science, Pub Med, and Cochrane Library) from 2010 to August 2024. Only scientific publications in English were included. Risk of bias assessment was performed. Results: Five articles were included in the study: four retrospective and one prospective observational studies. All patients' characteristics, including type of surgery, postoperative morbidities, adjuvant therapy, and recurrence, as well as SLN detection and oncological outcomes, have been reported. Four studies compared the scar-injection group (cases) with the tumor-injection group (controls); only one study described the SLNB after vulvar recurrence (second procedure), comparing it with SLNB during primary vulvar surgery (first procedure). Conclusions: SLNB is a feasible and safe option in patients who have had previous excision of the vulvar tumor and in patients with a recurrence of VSCC who are not able or willing to undergo lymphadenectomy. Moreover, it accurately reflects the nodal status in these patients.