Sentinel lymph node mapping using indocyanine green in patients with uterine and cervical neoplasms: restrictions of the method

Abstract

Purpose To establish the surgical, demographic and histopathological factors associated with inaccurate sentinel lymph nodes (SLNs) identification using indocyanine green (ICG) and near-infrared (NIR) fluorescence imaging in uterine and cervical neoplasms during both open and laparoscopic surgery. Methods We reviewed patients with atypical endometrial hyperplasia (AEH), clinical stage I and II cervical cancer or uterine malignancies who underwent primary surgery with SLN mapping between September 2015 and January 2018. An analysis of patients’ demographics, tumor factors and surgical approach was conducted. Bilateral and overall detection rates were calculated and univariate analysis was performed to estimate factors associated with failed SLN mapping. Results A total of 32 patients with uterine and cervical neoplasms were included in the study. The overall detection rate of the SLN was 84% and bilateral detection rate was 75%. There were no statistically relevant differences in overall and bilateral SLN detection rates by BMI, surgical approach or age. Regarding endometrial cancer, there were no differences in SLN detection rates when comparing tumor grade, histology nor myometrial invasion. For SLN detection failure, only the presence of metastatic lymph nodes and lack of surgical experience significantly increased the disability to detect SLNs ( p = 0.03, p = 0.04, respectively). Conclusions SLN mapping technique using NIR fluorescence imaging with ICG appears to be accurate method in most of the patients with cervical or endometrial carcinoma, regardless of demographic characteristics, tumor-related features and surgical approach. Surgeons’ expertise in that field allows obtaining excellent detection rates.

Defining the learning curve for successful staging with sentinel lymph node biopsy for endometrial cancer among surgeons at an academic institution

“…Higher SLN detection rates have been reported to be associated with intra-cervical injection and the use of indocyanine green 7 15. Additionally, patient- and tumor-related factors, including increased body mass index, clinically enlarged lymph nodes, and metastatic lymph nodes, have been associated with decreased bilateral mapping rates 12 13 16 17…”

Technetium-99m-indocyanine green versus technetium-99m-methylene blue for sentinel lymph node biopsy in early-stage endometrial cancer

“…Finally, a reduction in the factors associated with bilateral detection failure when using an isolated tracer. In the case of Tc-99m, mapping failure by both pre-operative SPECT/CT imaging and intra-operative gamma probe is mainly associated with incorrect tracer injection,14 30 that leads to major venous drainage or peritoneal extravasation. With regard to ICG, incorrect tracer injection is reported less frequently as a cause of mapping failure since the injection can be repeated if necessary.…”

“…There is increasing concern about the phenomenon of ‘empty node packet’. Bedyńska et al reported that almost 40% of the detection failure with ICG was due to ‘empty packets’ 30. Thomaier et al found that in the first 25 procedures the ‘empty node packet’ rate was 20%, compared with 7% in subsequent procedures 18.…”

The role of lymph node dissection in endometrial cancer: a systematic scoping review.

“…It reported reduced rates of readmission as well as decreased incidence of postoperative complications in the SLND group. In contrast, high grade and non-endometroid EC patients (confirmed on final histology) displayed failure in the mapping process (61) . Overall, SLND has shown promising results in early-stage EC however, better recognition and adoption may aid optimisation of SLN algorithms (3,60) .…”