Localization of malignant melanoma using monoclonal antibodies
J. Wasselle, J. Becker, W. Cruse, C. Espinosa, C. Cox and D. Reintgen
Department of Surgery, University of South Florida, Tampa 33682-0179.
Finding a screening test to evaluate patients with cancer for occult
metastatic disease, as well as imaging all known disease, is a goal of
research efforts. Twenty-nine evaluable patients with deeply invasive
(stage I), regional nodal (stage II), or systemic (stage III) melanoma
underwent imaging by administration of a preparation of the antimelanoma
antibody labeled with technetium 99m. Scan results indicated that 28 of 32
confirmed metastatic sites were imaged with this technique (88%
sensitivity). Analysis of the individual positive sites revealed that nodal
basins and visceral metastases accounted for the highest percentage of
metastatic sites imaged, with 14 (88%) of 16 nodal basin metastases and all
four visceral metastases being detected through imaging. Occult nodal
disease was detected in the iliac nodal chain in two of the 29 patients.
The imaging of benign tumors and nodal basins not containing disease
accounted for a confirmed false-positive rate of 21%. Three (10%) of the 29
scan results were confirmed to be false-negative. In vivo tumor
localization with monoclonal antibodies showed a sensitivity similar to
that of other roentgenographic procedures for identifying metastatic
disease and was useful in two of three patients in identifying occult iliac
nodal disease, a region that is difficult to evaluate with physical
examination and other imaging modalities.