Abstract:

Objective

To explore the direction, route and number of SLCs (Sentinel Lymphatic Channels) and their relationship with SLNs by using subareolar injection of technetium 99m sulfur colloid (⁹⁹Tc^m-SC).

Methods

Lymphoscintigraphy was performed in 91 breast cancer cases of stages Ⅰ～Ⅱ, and SLCs were identified successfully in 79 cases, in which the exit angle (θ_e) was tested.

Results

One SLC was identified in 74 cases, holding 93.67% and two SLCs were identified in 5 cases, holding 6.33%. And 6.33% of SLCs exited the areola with θ_e =0° ～30°( n =5),35.44% exited the areola with θ_e = 31° ～60°( n =28),and 56.96% exited the areola with θ_e = 61° ～90°( n =45); 98.73% of SLCs traveled through the upper, outer quadrant ( n =78), and terminated at an axillary SLN. No false negative or false positive was demonstrated by pathological analysis of SLNs which were identified according to SLCs.

Conclusions

Most SLCs exit the areola, traveled through the upper, outer quadrant and terminate at axillary SLNs. By using subareolar injection of ⁹⁹ Tc^m-SC, SLCs and SLNs can be identified preoperatively and dissected carefully during operation. The detection rate of SLCs can be improved and the false negative rate of SLNB can be reduced.

Key words: Breast neoplasm, Sentinel lymph node biopsy, Sentinel lymphatic channels, Technetium 99m sulfur colloid