Objective: The aim of the study was to determine the diagnostic accuracy and feasibility of sentinel lymph node (SLN) detection using a gamma probe in patients suffering from vulvar cancer.
Methods: From May 1998 to November 2000, 26 patients with early vulvar cancer, planned for local wide excision or vulvectomy including groin dissection, were eligible for the study. Two to 3 h before the planned procedure we injected technetium(99) m-labeled microcolloid intradermally at four locations around the tumor. Dynamic and static images were recorded using a gamma camera. SLN locations were marked on the overlying skin. In the operating theater SLNs were identified at the beginning of the procedure using a handheld gamma-detection probe. After resection of suspected SLNs a standard unilateral or bilateral groin dissection was performed, subsequently followed by local wide excision or, if indicated, radical vulvectomy. Sentinel node detection using technetium(99) m-labeled microcolloid was compared with final histopathological and immunohistochemical results.
Results: Scintigraphy showed focal uptake in all 26 patients. Intraoperatively we detected all sentinel nodes by handheld gamma probe. In 20 patients, one sentinel node was identified unilaterally, while in 6 patients two or more nodes were identified bilaterally. Histologically positive SLNs were found in 9 patients. In our preliminary series we did not find any false-negative SLN.
Conclusion: Identification of sentinel nodes in vulvar cancer is feasible with preoperatively administered technetium(99)m-labeled microcolloid. We confirm the results of previous studies and improve the evidence that the SLN procedure could be implemented in future therapy concepts.