Breast Cancer Sentinel Lymph Node Detection Rate: First Large Scale Multi-Centric Data for Technetium Phytate

Sentinel lymph node biopsy (SLNB) with injection of radiopharmaceuticals is now the standard of care for staging the axilla in patients with breast cancer. Sulfur or antimony colloids labeled with ^99mTechnetium (Tc) are used globally for the procedure, with a detection rate of 94%. However, in Iran, Tc phytate has been used because it is more easily producible in the country. The detection rate with Tc phytate has not been well determined in large-scale studies. Objective: We performed this study to report the detection rate of SLNB with Tc phytate, its advantages and disadvantages using large multicentric data.

This is a retrospective cross-sectional multicenter study. Participants were breast cancer patients without previous history of axillary surgery, who underwent sentinel node biopsy using Tc phytate on the morning of surgery or the day before. The detection rate was calculated as the number of patients with histologically positive sentinel nodes to all patients with histologically positive lymph nodes; we compared those injected on the day of surgery and those injected on the day before.

Overall, 2663 women aged 50.2±11.6 years were included. The detection rate was 91.8% (806 out of 878). The false negative rate was 8.2% overall, and statistically similar for injections on the day or the day before surgery (2.9 vs 2.1; P=0.32).

Tc phytate has a good detection rate for breast radio-guided SLNB with similar result for injections on the surgery day or the day before it.