Results of a standardized protocol for sentinel node imaging in breast cancer with Tc-99m labeled nanocolloidal albumin

Aim of this study was to evaluate the results of a standardized protocol fa r sentinel node (SN) detection in breast cancer using Tc-99m labeled nanoco lloidol albumin and a combined intra- and subdermal infection technique Met hods: One hundred and fifiy-five women with proven breast cancer (disease s tages Tis-TP) were included. Four infections of 10 to 15 NiBq of Tc-99m non ocolloid in 0.1 ml physiologic saline were administered intra- and subderma lly at the 3, 6, 9 and 12 o'clock positions in the skin overlying the tumor . Planer scintigraphic images in lateral and anterior projections were obta ined once between 2.5 and 18 hours after tracer administration. Guided by a gamma probe, all radioactive lymph nodes in the axilla were resected, then complete dissection followed. Results: In 151 of the 155 women (97.4%), no dal tracer uptake (range 1-7 foci, overage 2.2) was scintigraphically revea led. In one of there cases, drainage was only to the internal mammary lymph atic chain. Three of the 4 women with detection failure presented with hist ologically proven tumor infiltration of the lymphatics and axillary involve ment In 49 of the patients with visualized axillary lymph nodes (32.7%), at least one SN was metastatic. in 21 cases, this SN was the only positive no de. The remaining 101 patients with negative SN included 4 cases with axill ary involvement. The sensitivity of the SN with respect to the histological status of the entire axillo was thus 92.5%, the negative predictive value was 96.0%. The overall accuracy of The method was 97.3%. There was a signif icant difference between the number of totally detected radioactive nodes i n the groups with and without nodal metastases (3.49 vs. 2.57, p <0.01). Co nclusion: The described protocol represents an easy reproducible and reliab le method for SN detection in breast cancer that additionally allows flexib le timing of surgery Further, we found evidence that the number of scintigr aphically visualized nodes also reflects the histological status of the axi lla.