Lymphoscintigraphy in patients with breast cancer-related lymphedema after sentinel lymph node dissection and axillary radiation therapy.

The purpose of this study was to investigate lymphoscintigraphy pattern according to the presence or absence of axillary site radiation therapy (aRTx) in breast cancer-related lymphedema (BCRL) patients who underwent sentinel lymph node dissection (SLND). The participants were patients who visited our facility from July 2014 to June 2021 due to upper extremity edema. Among them, patients who underwent SLND after the diagnosis of breast cancer were included. The participants were divided into a group without aRTx (group A) and a group with aRTx (group B). In each patient's lymphoscintigraphy, axillary lymph node uptake (ALNU), lymphatic flow delay, dermal back flow, and the presence of any collateral pathway were checked. Thirty-three patients were enrolled. In all, 27 patients were classified in Group A, and 6 patients were classified in Group B. Between the 2 groups, we found a significant difference (P value < .05) between groups at ALNU and lymphatic flow delay. However, there was no significant difference between groups at the dermal backflow and the presence of a collateral pathway (P value > .05). And 24.2% of patients who developed lymphedema after SLND showed normal lymphoscintigraphy. In this study we suggest that SLND and aRTx affects the activity of the axillary lymph node and ultimately adversely affects lymphatic flow, becoming a risk factor for lymphedema. In addition, regardless of SLND or aRTx, lymphedema may eventually occur in the patient with normal lymphoscintigraphy.