Change in clinical management of sentinel lymph node location in early stage cervical cancer: the role of SPECT/CT

Objective

The aim of this study was to investigate the feasibility of the sentinel lymph node (SLN) identification with SPECT/CT lymphoscintigraphy imaging in the early stage invasive cervical cancer in patients undergoing radical hysterectomy and pelvic lymphadenectomy.

Methods

Between March 2007 and June 2009, a prospective consecutive study was designed for SLN mapping. Twenty-two patients with cervical cancer FIGO stage IB1 (n = 20) or stage IIA1 (n = 2) underwent SLN identification with preoperative SPECT/CT and planar images (technetium-99 m colloid albumin injection around the tumor) and posterior intraoperative detection with both blue dye and a handheld or laparoscopic gamma probe. Complete pelvic lymphadenectomy was performed in all cases by open (n = 2) or laparoscopic (n = 20) surgery.

Results

In the present series, a total of 35 SLN were detected with planar images and 40 SLN were identified and well located by SPECT/CT lymphoscintigraphy (median 2.0 nodes per patient). In 5/22 patients (22.7%) SPECT/CT procedure improves the number of localized SLN. Intraoperatively, 57 SLNs were identified, with a median of 3 SLNs per patient by gamma probe (a total of 53 hot nodes) and a median of 2 nodes per patient after blue dye injection (a total of 42 blue nodes). Microscopic nodal metastases (eight nodes, corresponding to four patients) were confirmed in 18.18% of cases; all these lymph nodes were previously detected as SLN. The remaining 450 nodes, including SLNs, following complete pelvic lymphadenectomy, were histologically negative.

Conclusions

Sentinel lymph node detection is improved by SPECT/CT imaging because of the increased number of SLN detected and the better tridimensional anatomic location, allowing easier intra-operative detection with gamma probe and showing, in this series, a 100% negative predictive value.