Technetium Tc 99m tilmanocept fails to detect sentinel lymph nodes in endometrial cancer

•Indocyanine green (ICG) is effective for sentinel lymph node detection (SLN) in endometrial cancer.•Technetium Tc 99m tilmanocept is FDA-approved for SLN detection in breast cancer, melanoma, and head and neck cancers.•We aimed to determine the SLN detection rate in endometrial cancer with concurrent technetium Tc 99m tilmanocept and ICG use.•Technetium Tc 99m tilmanocept failed to detect sentinel lymph nodes in endometrial cancer patients in our prospective study.•ICG alone remains a standard SLN detection technique in endometrial cancer, while limiting burdens from a dual agent.