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.