Our study was concerned with evaluation of patterns of lymph flow from primary breast cancer. Radionuclide scintigraphy (RS) of lymph nodes was performed in 92 patients. Scinitigraphic images were obtained 30-60 and 240-360 min after intratumoral injection of 75-150 MBq (0,5-1 vl) of 99mTc nanocolloids. The pool sites of the radiodrug collection were as follows: axillary (Ax), sub-supraclavicular (SSCL) and internal mammary (IM). Imaging proved effective in 86 cases. No drug transport was recorded in 5 cases; 4 of them revealed macroscopic metaststases to the lymph nodes. External involvement of the axillary lymph nodes was visualized in 51 patients out of 52 while in 26 it occurred on the axillary site only. In another 25 patients, images of lymph nodes were obtained on 2 or 3 sites: drainage Ax+SSCL (12;23.1%), Ax+IM (6;11.6%) and Ax+SSCL+IM (7;13.4%). In patients with tumors in internal quadrants (34), the lymph flow patterns were as follows: Ax (12;35.3%), IM (2;5.8%), Ax+SSCL (8;23.5%), Ax+IM+SSCL (5;14.7%). Hence, the efficacy of lymph node visualization after intratumoral injection of nanocolloids was 98%. Visualization on Ax sites was further confirmed by lymph flow to SSCL and IM (29.1%) and (35.9%), respectively. The likelihood of lymph flow to IM is significantly higher in patients with internal localization of breast cancer (37.1%) but it is not negligible (22.9%) in cases of external quadrants.