Use of Monoclonal Antibodies to Detect Metastases of Solid Tumors in Lymph Nodes

Abstract

Monoclonal antitumor antibodies provide the possibility of locating breast cancer metastases much smaller than those detectable by current non-invasive techniques. In the case of metastasis to axillary lymph nodes, a sensitive imaging technique might reduce the need for surgery. It might also detect small metastases in the internal mammary node chains, where surgical biopsy is not routinely performed. As an alternative to the more usual i.v. route of administration for monoclonal antibodies, we have been studying delivery via lymphatic vessels for detection of lymph node metastases. Using a metastatic hepatocarcinoma in guinea pigs, we find that subcutaneous injection for uptake by lymphatic capillaries leads to specific localization of antibody in lymph node metastases, as indicated by gamma camera imaging, double-label isotopic tracers, and autoradiography. When lymph nodes are the target, the lymphatic route offers higher efficiency, faster localization, and less systemic toxicity than does the i.v. route. In addition, there may be less cross-reaction with antigen expressed on normal cells.