Sentinel Lymph Node Biopsy in Endometrial Cancer--Comparison of 2 Detection Methods.

Objectives: Sentinel lymph node biopsy (SLNB) can identify patients with nodal metastases who are eligible for tailored treatment. The aim of study was to compare the SLN detection rates using cervical and subserosal administration of 2 tracers.
Results: In group 1 (82 patients), SLNB was performed using radiocolloid injected to the cervix and blue dye administered to the fundus. In group 2, blue dye was injected to cervix and fundus (106 patients). Only SLNB was performed in 128 (68.1%) women. In the remaining 60 (31.9%) patients, pelvic/para-aortic lymphadenectomy together with SLNB was performed. Groups 1 and 2 did not differ with regard to the frequencies of SLNB and lymphadenectomy. The detection rate for both groups was 90.9%. Bilateral detection was achieved in 72.5%. Para-aortic SLNs were found in 9.6%. Detection rates in groups 1 and 2 were 95.1% and 87.7% (P = 0.065). In comparison of cervical administration of radioisotope and subserosal injection of blue dye in group 1, we found a significant difference for total SLN detection (91.5% vs 74.4%, P < 0.05) and no significant difference for bilateral detection (73.3% vs 59.1%, P = 0.776). We did not find differences in the para-aortic SLN detection rates achieved after administration of a radiotracer and injection of a blue dye (4.9% vs 9.8%, P = 0.184). Eighteen patients (9.6%) presented with nodal disease, including 15 women with SLN involvement. The false-negative rate, calculated for patients subjected to lymphadenectomy, was 12.5% (1/8); using the SLNB surgical algorithm, it was 10% (1/10).
Conclusions: Cervical administration of a tracer, especially radioisotope, results in high SLN detection rates. In turn, the subserosal injection can be used only as an adjuvant method for SLNB. Low para-aortic SLN detection rates observed after cervical administration of a tracer do not seem to be a serious limitation of this technique.