Injection Methods in Finding the Sentinel Lymph Node During Lymphatic Mapping and Sentinel Lymph Node Biopsy in Patients With Invasive Breast Cancer

OBJECTIVES: * Compare subareolar injection with peritumoral injection in identifying the sentinel node during breast lymphatic mapping in patients with invasive breast cancer. * Compare the lymphatic drainage patterns using lymphoscintigraphy of the breast with subareolar injection vs peritumoral injection. OUTLINE: At least 2 days before scheduled surgery, patients receive technetium Tc 99m sulfur colloid by peritumoral injection followed by lymphoscintigraphy. Images are obtained at 30 minutes and after 2 and 3 hours, provided no drainage is noted. Patients then receive technetium Tc 99m sulfur colloid by subareolar injection followed by another lymphoscintigraphy. At the time of surgery, patients receive isosulfan blue by subareolar injection. A handheld gamma probe is used to locate the sentinel node. If the sentinel node is identified, it is excised and the scheduled breast surgery is performed. If the sentinel node cannot be identified, patients undergo the scheduled breast surgery. PROJECTED ACCRUAL: A total of 100 patients will be accrued for this study within 12.5 months.