The results of sentinel lymph node imaging and biopsy with a novel lymphoscintigraphy agent 99 Tc m -Rituximab in 247 breast cancer patients

Objective The feasibility, reliability and influence factors of sentinel lymph node (SLN) imaging and biopsy with a new imaging agent 99Tcm-Rituximab were investigated in 467 breast cancer patients. Methods The SLN imaging was taken after peritumoral and subdermal injection of 99Tcm-Rituximab guided by ultrasound. Based on the image, the SLN were identified by a gamma probe and removed, the resected SLN were examined pathologically with both HE and immunohistochemical staining. Results The success rate of SLN imaging was 99.14% (463/467). A total 837 SLN (1.79 per case) were visualized, which located in axilla, internal mammary, subraclavicular and breast region. The success rate of SLN biopsy (SLNB) was 99.57% (465/467), a total 1182 SLN (2.53 per case) were identified. Pathological examination showed that there were 131 patients with 194 metastatic axillary SLN; one case of micrometastases was confirmed by immunohistochemical staining, whose result of HE staining was negative. The following factors, such as age, image time, biopsy history, pathologic type and clinical stage, had no effect on the resuits of SLN imaging and SLNB. But the SLN metastasis rates were different in patients with different pathologic type and clinical stage(x2=14.134, 29.184, all P <0.05). Conclusion 99Tcm-Rituximab showed potential in both SLN imaging and identification in breast cancer patients. Key words: Breast neoplasms;  Lymph nodes;  Radionuclide imaging;  Technetium;  Rituximab