Sentinel lymph node detection following the hysteroscopic peritumoural injection of 99mTc-labelled albumin nanocolloid in endometrial cancer.

PURPOSE: The purpose of this study was to assess the feasibility of sentinel lymph node (SLN) detection in endometrial cancer patients with a dual-tracer procedure after hysteroscopic peritumoural injection.
METHODS: Twenty-six women with previously untreated endometrial adenocarcinoma underwent the hysteroscopic injection of 111 MBq 99mTc-Nanocoll and blue dye administered subendometrially around the lesion. On the same day, all 26 patients underwent lymphoscintigraphy, followed 3-4 h later by hysterotomy with bilateral salpingo-oophorectomy and pelvic lymphadenectomy. Para-aortic lymphadenectomy was also performed in cases of either serous or papillary carcinoma (n=7/26). All SLNs were removed and examined with haematoxylin and eosin staining and immunohistochemical techniques.
RESULTS: The procedure was well tolerated by patients, only two experiencing transient vagal symptoms. The sensitivity of this technique for correct identification of SLNs was 100%. Lymph node metastases were found in 4 out of the 26 patients (15%), bilaterally in the external iliac region (n=1), unilaterally in the external iliac region (n=1), unilaterally in the common iliac region (n=1) and unilaterally in the para-aortic region (n=1). In all four cases, nodal metastases were located within SLNs detected by lymphoscintigraphy. Only 10 of the 26 patients (38%) had significant blue dye staining. All blue-stained SLNs were radioactive.
CONCLUSION: In patients with endometrial cancer, it is feasible to use lymphatic mapping and SLN biopsy to define the topographic distribution of the lymphatic network and also to accurately detect lumbo-aortic and pelvic metastases within SLNs. In the majority of patients with early stage endometrial cancer, this procedure may avoid unnecessary radical pelvic lymphadenectomy. It may also guide para-aortic lymph node dissection on the basis of the SLN status.