Mammary Lymphoscintigraphy in Breast Cancer

Lymphoscintigraphy has previously been used to define lymph drainage patterns and locate sentinel lymph nodes, prior to surgery, in patients with cutaneous melanoma. The aim of this study was to apply this technique to patients with breast cancer using intramammary injections placed around the primary tumor in the breast. Lymphoscintigraphy using 99mTc-labeled antimony sulphide colloid was performed in 34 patients with a suspected primary breast cancer. Images were recorded immediately and at 2.5 hr using a LFOV digital gamma camera. Sentinel lymph node location was marked when possible. Lymphatic drainage patterns were successfully recorded in all but three patients. Lymph drainage was to the axillary, internal mammary, supraclavicular and, in one patient, infraclavicular node fields in various combinations but always on the same side of the body as the breast tumor. There was unexpected drainage across the center line of the breast to axillary or internal mammary nodes in 32% of patients with inner or outer quadrant lesions. Direct drainage to supraclavicular or infraclavicular nodes occurred in 20% of upper quadrant lesions. Drainage to the ipsilateral axilla occurred in 85% of patients, where a single sentinel node was seen in all cases. Intramammary lymphoscintigraphy can be used to define the lymphatic drainage patterns of individual breast cancers. The surface location of sentinel lymph nodes in the draining node fields can be marked and in the axilla their depth can be measured. It should therefore be possible to use lymphoscintigraphy, along with a blue dye injection technique or the gamma probe at surgery, to locate sentinel lymph nodes in patients with breast cancer.