Despite all these data, SLN biopsy alone is not considered as gold-standard for SLN staging yet. The critical endpoint is the long-term survival of patients with bilateral negative SLN who are deemed to be free of nodal involvement and who did not receive adjuvant treatment. The survival and the oncologic outcomes of patients who underwent SLN biopsy alone are poorly reported in the literature. In the retrospective analysis of Lennox and Covens, there was no difference between patients who underwent bilateral SLN biopsy alone and those who underwent bilateral pelvic lymphadenectomy in terms of 2-year DFS (97% vs. 95%) and 5-year DFS (93% vs. 92%). In a post-hoc analysis of both SENTICOL I and SENTICOL II cohorts presented at the ASCO 2020, the DFS patients with bilateral negative SLN were similar to that of node-negative patients who underwent bilateral pelvic lymphadenectomy, 85.1% vs. 80.4%, P=0.24 respectively. However, both of these studies were not designed to demonstrate the non-inferiority of SLN biopsy in terms of survival.
Therefore, prospective clinical trials with large cohort are mandatory to validate the oncologic safety of SLN biopsy alone in cervical cancer. The results of the LACC trial have proven that only randomized clinical trial thoroughly conducted can evaluate medical and therapeutic techniques.[107,108]
To date, three ongoing prospective clinical trials aim to assess the oncological outcomes of SLN biopsy in early stage cervical cancer: the SENTIX trial, the PHENIX trial and the SENTICOL III trial. The SENTIX trial (NCT02494063) is a prospective multicentric observational trial which aims to assess the 2-year recurrence rate after SLN biopsy alone. The PHENIX trial (NCT02642471) is multi-center randomized controlled trial which aim to compare the oncological outcomes of SLN biopsy with pelvic lymphadenectomy in patients with (2-year DFS) and without (3-year DFS) SLN metastasis. The SENTICOL III trial is a prospective multicentric randomized trial which aims to compare 3-year disease-free survival between SLN biopsy alone and SLN biopsy with pelvic lymphadenectomy.
Chin Clin Oncol. 2021;10(2):18 © 2021 AME Publishing Company