Themost sensitive and specific parameter for determining the HER2/neu status inthe mALNs of BC patients using [99mTc]Tc-(HE)3-G3 was themALN-to-background ratio: AUC of 0.83 (95% CI 0.63–1.00), sensitivity of80%, and specificity of 80%; a threshold value of > 12.25 a.u. For themALN-to-LDM ratio, these parameters were as follows: AUC of 0.78 (95% CI0.58–1.00), sensitivity of 70%, and specificity of 70%; a threshold valueof > 10.25 a.u. (Fig. 5). The gene discussed is ERBB2; the disease is breast cancer.