Characterization of Patients with Endometrial Cancer and Low-Volume Nodal Disease

Background: Isolated tumor cells (ITCs) are deposits measuring ≤0.2 mm, whereas micro metastasis (MM) measures >0.2 to ≤2 mm. The significance of these findings in endometrial cancer remains controversial. We sought to determine whether patient and disease characteristics correlate with ITCs/MM on sentinel lymph node (SLN) biopsy for endometrial cancer staging. Methods: We carried out an IRB-approved retrospective chart review of all women with endometrial cancer who underwent SLN biopsy during staging at two medical centers between 2013 and 2018. Results: A total of 472 patient charts met inclusion criteria. Among women included, 5.7% (n = 27) had ITCs/MM. The median age of women with ITCs/MM was 64 years and median BMI was 33.8. Neither was found to be related to ITCs/M. Lymphovascular space invasion (LVSI) was present in 73% (n = 19). Compared to patients without LVSI, those with LVSI were more likely to have ITCs/MM (OR = 7.61, 95% CI 3.00–19.32). Compared to patients with superficial invasion of the myometrium, those with a greater myometrial invasion were more likely to have ITCs/MM (OR = 6.37, 95% CI 1.90–21.37). Conclusion: ITCs/MM are relatively rare in women undergoing SLN biopsy for endometrial cancer. Additional data are needed to clarify risk factors and associated patient outcomes.