Role of pre-sacral sentinel lymph nodes in endometrium and cervical cancer: experience with minimally invasive indocyanine green sentinel lymph node mapping.

OBJECTIVE

The aim of this study was to examine the role of pre-sacral sentinel lymph nodes (SLNs) in patients with uterine cancer.

METHODS

This retrospective cohort study includes patients with endometrial or cervical cancer who underwent minimally invasive indocyanine green SLN mapping at the Bern University Hospital from December 2012 to December 2022. A complete ultra-staging of the SLNs was performed in all cases.

RESULTS

A total of 616 patients with uterine cancer were included in this study. The mean age was 61.6 years (standard deviation ± 13.8) and mean body mass index 28.2 kg/m2 (standard deviation ± 7.3). Endometrial cancer was present in 466 patients, and 150 patients were diagnosed with cervical cancer. The overall SLN detection rate was 97.7%. In total, 2462 SLNs were removed, with a median number of 3 SLNs (range; 0-20) per patient. In 95 patients, the SLN showed tumor involvement comprising macro-metastasis in 74 patients (12.0%), micro-metastasis in 17 patients (2.8%), and isolated tumor cells in four patients (0.6%). In 170 patients, 384 pre-sacral SLNs were removed. Pre-sacral SLNs were more often seen in patients with cervical cancer (35.3%) than in those with endometrial cancer (25.1%) (p = .021); Three patients had macro-metastasis in the pre-sacral SLNs, accounting for 0.5% of the entire cohort. These three patients had high-grade endometrial cancer, and all had a concurrent positive pelvic SLN mapping result.

CONCLUSION

In our study, indocyanine green SLN mapping revealed pre-sacral SLN in one-third of patients with cervical and one-fourth of those with endometrial cancer. Pre-sacral SLN metastasis was present in 0.5% of all study patients. The relevance of pre-sacral SLNs seems to be limited to patients with high-risk endometrial cancer.