title: Immunolymphoscintigraphy of pulmonary and mediastinal lymph nodes in dogs: a new approach to lung cancer imaging.
abstract: Despite improved resolution with new imaging techniques, surgical confirmation of mediastinal lymph node status is often required for reliable staging of patients with non-small cell lung cancer. Recent scintigraphic studies suggest that s.c. administration of radiolabeled antibodies can be more efficient than the i.v. route for targeting regional lymph nodes in animals and humans. To determine if this approach could be applied to the lymphatics of the lung, we injected both specific and irrelevant radiolabeled monoclonal antibodies via a flexible fiberoptic bronchoscope through the mucosa of lobar bronchi in normal dogs. The injected antibodies were expected to drain by way of local lymphatic vessels toward the central lymph nodes, in effect following the same pathway as do cells metastasizing to these nodes during early regional tumor dissemination. To accomplish this, anesthetized dogs were intubated and then coinjected with the two labeled antibodies [600 microCi/100 micrograms (total)] through a fiberoptic bronchoscope. The animals were serially imaged and then autopsied 14-36 h after injection. Individual hilar and carinal nodes contained over 1% of the injected 131I-labeled specific antibody dose and the average selectivity was 2.5:1 with respect to a coinjected irrelevant IgG. Distant organs (mesenteric lymph node, liver, spleen, bone marrow, and lung parenchyma other than the injection site) contained much less radioactivity, and those sites accumulated a greater fraction of the non-specific labeled antibody. The ratio of iodine-131 to iodine-125 counts between hilar/carinal lymph nodes and abdominal lymph nodes ranged from 15:1 to 100:1. These initial studies indicate efficient delivery of antibody to a subset of the regional nodes via pulmonary lymphatics. They suggest the feasibility of this technique which may be of use in the detection and perhaps therapy of human lung cancer metastases in regional lymph nodes.
authors.forename: J L
authors.initials: JL
authors.lastname: Mulshine
authors.forename: A M
authors.initials: AM
authors.lastname: Keenan
authors.forename: J A
authors.initials: JA
authors.lastname: Carrasquillo
authors.forename: T
authors.initials: T
authors.lastname: Walsh
authors.forename: R I
authors.initials: RI
authors.lastname: Linnoila
authors.forename: O D
authors.initials: OD
authors.lastname: Holton
authors.forename: J
authors.initials: J
authors.lastname: Harwell
authors.forename: S M
authors.initials: SM
authors.lastname: Larson
authors.forename: P A
authors.initials: PA
authors.lastname: Bunn
authors.forename: J N
authors.initials: JN
authors.lastname: Weinstein
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage; D001999:Bronchoscopy; D004285:Dogs; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D007279:Injections, Subcutaneous; D008099:Liver / Q000000981:diagnostic imaging; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D008198:Lymph Nodes / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D013154:Spleen / Q000000981:diagnostic imaging; D014018:Tissue Distribution
chemical_list: D000911:Antibodies, Monoclonal; D000949:Histocompatibility Antigens Class II