Early Dynamic Versus Late Static Lymphoscintigraphy for the Identification of Sentinel Lymph Nodes in Breast Cancer

Purpose: Sentinel lymph node (SLN) biopsy is an established method for the identification of early breast cancer metastases. SLN lymphoscintigraphy is pivotal in many cases, but the diagnostic value of early dynamic versus late static imaging procedures remains unclear. The objective of this study was to evaluate the diagnostic value of early dynamic versus late static imaging in the identification of SLN in breast cancer patients. Materials and Methods: A total of 104 consecutive female patients who were referred for SLN scintigraphy prior to breast cancer surgery were included in this retrospective study. All patients underwent both a 20-minute dynamic lymphoscintigraphy and a 2-hour static acquisition. The images were independently evaluated for the presence, location, and numbers of SLN and echelon nodes in a blinded and random manner by 2 trained observers. Any discrepancy was solved by a third party arbitrator. Results: SLN was identified in 101 of 104 (97%) patients on the static images versus 41 of 104 (39%) of the patients based on the dynamic acquisition. The combined use of dynamic and static images did not increase the diagnostic performance versus late lymphoscintigraphy alone. Conclusions: Identification of SLN by lymphoscintigraphy in breast cancer can be performed using a 2-hour static image alone.