Optimal timing of sentinel node detection using [99mTc]Tc-phytate lymphoscintigraphy: A study of 100 breast cancer patients

Introduction

Sentinel lymph node biopsy guided by preoperative lymphoscintigraphy is an established technique for axillary staging in breast cancer. However, the optimal timing for lymphoscintigraphic imaging remains unclear. Earlier acquisition may expedite surgery while later imaging improves detection rates by allowing radiotracer transit. Defining the timeframe maximizing accuracy and minimizing burden is needed.

Objective

To evaluate optimal acquisition timings for [99mTc]Tc-Phytate lymphoscintigraphy in sentinel lymph node mapping for breast cancer.

Methods

Hundred breast cancer patients underwent periareolar injection of 1–2 mCi [99mTc]Tc-Phytate and lymphoscintigraphy at 5,10, 30, 60 and 120 min post-injection. Lymph node visualization was assessed by experienced nuclear medicine physicians based on retrospective review of scintigraphy images. Descriptive statistics characterized patient demographics and time to sentinel lymph node detection. Correlation analyses evaluated relationships between visualization parameters and factors such as age, sex and surgical history.

Results

Lymph nodes were typically visible within 10 min (median). Regression found no significant predictors of prolonged transit time among age, sex, surgical history. Age is not a statistically significant predictor of node visualization (p = 0.129). Also sex and surgery history are not significant predictors of longer time (p > 0.05).

Conclusion

Sentinel lymph node biopsy guided by lymphoscintigraphy is an important technique for axillary staging in breast cancer. Standardizing acquisition timing could optimize the accuracy and efficiency of lymphoscintigraphy for axillary staging.