R Rajagopalan Iyer

Sentinel SENECA risk factors for unsuccessful bi-lateral sentinel lymph node mapping in endometrial cancer

Our study aims to assess the risk factors associated with bi-lateral sentinel lymph node (SLN) mapping failure in endometrial cancer. The SENECA study was a retrospective multi-center international observational study that reviewed data from 2139 women with clinical stage I-to-II endometrial cancer across 64 centers in 17 countries. Between January 2021 and December 2022, patients underwent surgical treatment with SLN assessment, following the guidelines of the European Society of Gynaecological Oncology. Risk factors associated with the absence of bi-lateral mapping were analyzed using χ Among the 2139 patients, the bi-lateral lymph node detection rate was 82.7%, whereas the unilateral detection rate was 97.3%. In multi-variate analysis, 5 risk factors remained statistically associated with unsuccessful bi-lateral lymph node mapping: high-grade histology (OR 1.35, 95% CI 1.02 to 1.79, p=.03), myometrial invasion >50% (OR 1.37, 95% CI 1.07 to 1.75, p=.012), low-volume surgeon <20 cases/year (OR 2.11, 95% CI 1.55 to 2.89, p<.01), open surgical approach (OR 1.72, 95% CI 1.06 to 2.78 , p=.03), and non-indocyanine green tracer (OR 4.59, 95% CI 2.64 to 7.99, p<.01). The addition of bi-lateral pelvic lymphadenectomy and/or paraaortic lymphadenectomy to SLN biopsy caused an increased rate of intra-operative complications (2% vs 8.4%, p<.01) and all-grade post-operative complications (4.1% vs 11.2%, p<.01). Our study identifies 5 risk factors associated with unsuccessful lymph node mapping in endometrial cancer. Efforts should be made to perform this technique with indocyanine green, through minimally invasive surgery, and performed or supervised by an experienced surgeon with ≥20 endometrial cancer cases per year.

SENECA study: staging endometrial cancer based on molecular classification

Management of endometrial cancer is advancing, with accurate staging crucial for guiding treatment decisions. Understanding sentinel lymph node (SLN) involvement rates across molecular subgroups is essential. To evaluate SLN involvement in early-stage (International Federation of Gynecology and Obstetrics 2009 I-II) endometrial cancer, considering molecular subtypes and new European Society of Gynaecological Oncology (ESGO) risk classification. The SENECA study retrospectively reviewed data from 2139 women with stage I-II endometrial cancer across 66 centers in 16 countries. Patients underwent surgery with SLN assessment following ESGO guidelines between January 2021 and December 2022. Molecular analysis was performed on pre-operative biopsies or hysterectomy specimens. Among the 2139 patients, the molecular subgroups were as follows: 272 (12.7%) p53 abnormal (p53abn, 1191 (55.7%) non-specific molecular profile (NSMP), 581 (27.2%) mismatch repair deficient (MMRd), 95 (4.4%) POLE mutated (POLE-mut). Tracer diffusion was detected in, at least one side, in 97.2% of the cases; with a bilateral diffusion observed in 82.7% of the cases. By ultrastaging (90.7% of the cases) or one-step nucleic acid amplification (198 (9.3%) of the cases), 205 patients were identified with affected sentinel lymph nodes, representing 9.6% of the sample. Of these, 139 (67.8%) had low-volume metastases (including micrometastases, 42.9%; and isolated tumor cells, 24.9%) while 66 (32.2%) had macrometastases. Significant differences in SLN involvement were observed between molecular subtypes, with p53abn and MMRd groups having the highest rates (12.50% and 12.40%, respectively) compared with NSMP (7.80%) and POLE-mut (6.30%), (p=0.004); (p53abn, OR=1.69 (95% CI 1.11 to 2.56), p=0.014; MMRd, OR=1.67 (95% CI 1.21 to 2.31), p=0.002). Differences were also noted among ESGO risk groups (2.84% for low-risk patients, 6.62% for intermediate-risk patients, 21.63% for high-intermediate risk patients, and 22.51% for high-risk patients; p<0.001). Our study reveals significant differences in SLN involvement among patients with early-stage endometrial cancer based on molecular subtypes. This underscores the importance of considering molecular characteristics for accurate staging and optimal management decisions.