LAUSR

We read the review article conducted by Crivellaro et al. and published online on 6 March 2018, to update the recent published literature on sentinel lymph node (SLN) procedures in endometrial cancer (ECs) [1]. Crivellaro et al. found that indocyanine green (ICG) and the combination of radiotracer/ blue dye resulted in the highest SLN detection rates: 95% (95% CI 86–100%) and 90% (95% CI 79–100%) with cervical injection, respectively. ICG demonstrated the highest values of bilateral nodal mapping 75% (95% CI 60–91%) with cervical injection [1]. However, Bodurtha Smith et al. in a systematic review found that the current data favor the use of cervical injection techniques with indocyanine green for SLNs detection, and they concluded that the use of indocyanine green increased the bilateral detection rate compared with blue dye [2]. Bodurtha Smith et al. also concluded that the cervical injection increased the bilateral SLNs detection rate, but decreased the para-aortic detection rate [2]. Regarding the methods of SLN detection in ECs, Favero et al. conducted a prospective study to determine the feasibility and accuracy of laparoscopic SLN biopsy in ECs obtained through hysteroscopic injection of technetium-99 (Tc-99) [3]. Favero et al. concluded that endoscopic SLN biopsy obtained through hysteroscopic injection of Tc-99 is a feasible and safe method with 73% (31/42) SLNs detection rate [3]. A prospective study conducted by Kataoka et al. to evaluate the diagnostic value of SLNs mapping using hysteroscopic sub-endometrial injection of 99 m-technetium labelled phytate (radioisotope; RI method), and sub-serosal indocyanine green (ICG) injection (dye method) in women with ECs [22]. Kataoka et al. concluded that their method for SLNs mapping in ECs revealed high detection rate with high sensitivity and negative predictive value (NPV) [4]. In addition, Nagi et al. found that the one-step nucleic acid amplification (OSNA) assay using CK19 mRNA was applicable for detecting lymph node metastasis in ECs [5]. Robova et al. conducted a review article to evaluate different techniques of injection, and histopathologic elaboration of SLNs in ECs. They found that the hysteroscopic injection is not easy to learn, and the exact peri-tumoral injection in large tumors is often impossible [6]. In addition, they found that the sub-serosal administration of tracer is difficult during laparoscopic or robotic surgery, and the cervical injection is a controversial technique because the distribution of SLNs in ECs is different from cervical cancers [6]. Although, the current data favors the use of cervical injection of indocyanine green for SLNs detection, others argue that this technique is controversial because the distribution of SLNs in ECs is different from cervical cancers. Please clarify to the readers how Crivellaro et al. found that the ICG demonstrated the highest values of bilateral nodal mapping in ECs 75% (95% CI 60–91%) with cervical injection [1], in spite of the previous conclusion of Bodurtha Smith et al. that cervical injection decreased the para-aortic lymph node detection rate in ECs [2] and the conclusion of Robova et al. that cervical injection is a controversial A response to these comments can be found at https ://doi. org/10.1007/s4033 6-018-0281-z.