MAMMARY LYMPHOSCINTIGRAPHY IN BREAST-CANCER

Lymphoscintigraphy has previously been used to define lymph drainage p atterns and locate sentinel lymph nodes, prior to surgery, in patients with cutaneous melanoma. The aim of this study was to apply this tech nique to patients with breast cancer using intramammary injections pla ced around the primary tumor in the breast. Methods: Lymphoscintigraph y using Tc-99m-labeled antimony sulphide colloid was performed in 34 p atients with a suspected primary breast cancer. Images were recorded i mmediately and at 2.5 hr using a LFOV digital gamma camera. Sentinel l ymph node location was marked when possible. Results: Lymphatic draina ge patterns were successfully recorded in all but three patients. Lymp h drainage was to the axillary, internal mammary, supraclavicular and, in one patient, infraclavicular node fields in various combinations b ut 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 o r internal mammary nodes in 32% of patients with inner or outer quadra nt lesions. Direct drainage to supraclavicular or infraclavicular node s occurred in 20% of upper quadrant lesions. Drainage to the ipsilater al axilla occurred in 85% of patients, where a single sentinel node wa s seen in all cases. Conclusion: Intramammary lymphoscintigraphy can b e 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 measure d. It should therefore be possible to use lymphoscintigraphy, along wi th a blue dye injection technique or the gamma probe at surgery, to lo cate sentinel lymph nodes in patients with breast cancer.