Sentinel lymph node detection in patients with vulvar carcinoma; Feasibility of intra-operative mapping with technetium-99m-labeled nanocolloid.

AIMS: Sentinel lymph node (SLN) mapping appears to be feasible in patients with primary vulvar cancer. Previous protocols describe the injection of the technetium-99m-nanocolloid at least 3 h before surgery which involves two invasive procedures for the patient. In this study, we assessed the feasibility, safety, and accuracy of an intra-operative rather than preoperative SLN mapping in patients with primary vulvar cancer.
METHODS: Patients with histologically confirmed squamous cell vulvar cancer and clinically FIGO stage Ib disease underwent intra-operative SLN mapping by intradermal injection of the nanocolloid around the tumor. SLN were identified and removed before a complete inguinofemoral lymphnode dissection was performed. Surgical and pathologic data on all patients were prospectively entered into a database.
RESULTS: An SLN procedure was performed in 16 patients; 3 patients received unilateral lymphadenectomy, and 13 women underwent surgery on both groins. In all groins but 4 at least one SLN was clearly identified (detection rate 25/29, 86%). A median number of 2 SLN and 4 non-SLN per groin were removed. 3 of 16 patients (19%) had metastatic disease in the lymph nodes. There was no false negative SLN result.
CONCLUSION: Intra-operative SLN detection seems feasible in patients with early stage vulvar cancer. More patients need to be enrolled in this ongoing study before this more convenient technique can be considered safe.