Pathological factors associated with non-sentinel lymph node metastasis in early stage cervical cancer

Objective: To analyze the predictive factors for non-sentinel lymph node (non-SLN) metastasis in early-stage cervical cancer. Methods: We analyzed a series of 113 patients who underwent sentinel lymph node (SLN) mapping for cervical cancer. The SLNs were examined by immunohistochemistry (IHC) when the hematoxylin-eosin stain was negative. Results: The overall bilateral detection rate was 81.5%, with a median of two SLNs resected. The study ultimately included 92 patients with SLNs that were mapped who had also undergone systematic pelvic lymph node dissection. Thirteen (14.1%) patients had positive SLNs, with a median of one positive SLN. Regarding the size of SLN metastasis, one (1.1%) had isolated tumor cells (ITC), seven (7.6%) had micrometastases, and five (5.4%) had macrometastases. Notably, 46.1% (6/13) had lymph node metastases detected only after IHC. Five (38.5%) cases had positive non-SLNs, with a median count of one positive lymph node. Parametrial invasion was the only risk factor for positive non-SLN (p = .045). Regarding the size of SLN metastasis, non-SLN involvement was present in the only case with ITC (1/1), 42.9% (3/7) of cases with micrometastases, and in 20% (1/5) with macrometastases. Conclusions: Our data suggest that parametrial invasion correlates with the risk of non-SLN metastasis in cervical cancer.