Promising results using sentinel node biopsy as a substitute for radical lymphadenectomy in endometrial cancer staging.

Introduction: The objective of this study was to evaluate the efficacy of the sentinel node (SN) procedure in endometrial cancer patients.

Material And Methods: This was a prospective follow-up study including patients referred to Herlev Hospital, Denmark, to be treated for endometrial cancer in the period from October 2005 to December 2008. Hysteroscopy was performed with a 4.5 mm hysteroscope. Injections of 100-150 MBq (99m)Tc-traced colloid were administered subendometrially, and a dynamic scintigram was made. SN(s) identified with a gammaprobe were resected at the operation, and frozen sections were performed, followed by radical pelvic and para-aortic lymphadenectomy.

Results: A total of 32 patients were included. Among patients without clinical macro-metastases (n = 27), the SNs were detected by gamma probe in 23 (85.2%), and in most patients (n = 17, 74.0%) one (n = 12) or two (n = 5) SNs were found. The consistency between the scintigram and peroperative findings increased from 50.0% to 78.9% when the dose of (99m)Tc was increased to 150 MBq, mostly because the detection failure rate was lower at the higher dose: 4.8% versus 18.2%. By frozen section all macro-metastases were confirmed, but only one micro-metastasis was diagnosed. All subsequent lymph node metastases found in the final histology were found in SNs, i.e. no false negative SNs were found.

Conclusion: The SN procedure can be used for endometrial cancer and it has a high detection rate and no false negative SNs were detected. The sensitivity of the SN procedure may be increased by the use of single-photon emission computed tomography (SPECT)/computed tomography (CT) and peroperative cytokeratin (CK) staining of the SN(s).

Funding: External funding was received from the following University Foundation, Copenhagen County Research, Manufacturer Einar Willumsen's Memorial Foundation, Toyota Foundation Denmark, Lilly Benthine Lund Foundation.

Trial Registration: The study was registered with the Danish Data Protection Agency.