The diagnostic value of SLN biopsy is one of the most critical aspects of this technique. It has been demonstrated that bilateral negative SLN strongly predicted the absence of pelvic node involvement.[74,75] The main current challenge of this technique is to achieve maximal sensitivity and lowest false-negative rates. The false negativity rate is of paramount importance since the majority of node-negative patients do not receive adjuvant treatment and the nodal recurrence worsens severely the prognosis. Based on simple criteria such as early stage (IA2, IB1, IIA1 2018 FIGO stage), no suspicious pre-, and per-operative lymph nodes, and bilateral negative SLNs after ultrastaging, the false-negative rate may be very low at 0.08% in eligible patients.
Due to its central topography, historic anatomic work has proven that the uterine cervix has in fact a bilateral lymphatic drainage and both hemipelvises have to be considered regarding two distinct lymphatic drainage pathway. Bilateral SLN detection is therefore of utmost importance to be fully reliable.[74,75,77] However, bilateral SLN detection is obtained in 60% of cases only. In a large prospective cohort of 405 patients, lower bilateral SLN detection rate was associated with Age ≥70 years, tumor size larger than 20 mm and Body-mass index higher than 30 kg/m2. As previously mentioned, a learning-curve for SLN biopsy is required and the experience of the surgeon is essential.
Applying the MSKCC algorithm that is based on bilateral detection and sampling of all labeled nodes appears as a pertinent strategy since the majority of involved nodes are more likely diagnosed from the SLN removed rather than the non SLN ones. Following an anatomically-based surgical algorithm, a precise and careful dissection of the retroperitoneal space may help to find SLN in atypical localization. Moreover, the SLN status may be considered to predict the parametrial involvement and to determine the type of radical hysterectomy to be performed.[78,79]
Chin Clin Oncol. 2021;10(2):18 © 2021 AME Publishing Company