The injected activity would depend on the interval between injection and surgery. In my centre, the elective surgery is only done the next day; about 20-24hr post-injection. So, the dose we used is about 37MBq, injected  at 9 O'clock using peri-areolar approach (single dose/ site).  Image acquisition is performed after 5min post-injection.

We  use  30 MBq for same day imaging. Injecting  intracutan gives tue fastest results.