Scintimammography with 11 beta-methoxy-(17 alpha,20Z)-[I-123]iodovinylestradiol: A complementary role to Tc-99m-methoxyisobutyl isonitrile in the characterization of breast tumors

The aim of this study was to investigate a possible relationship between Tc -99m-methoxyisobutyl isonitrile (MIBI) uptake and the estrogen receptor (ER ) status of breast tumors as determined by 11 beta-methoxy-(17 alpha,20Z)-[ I-123]iodovinylestradiol (MIVE) scintimammography. Methods: Thirteen patien ts referred for MIVE scintimammography after abnormal mammography or findin g of a suspect mass on physical examination were injected intravenously wit h MIVE. Planar images of the breasts and axillary region were taken with bo th radiopharmaceuticals and compared with pathologic examination of the tum or tissue and in vitro ER quantification. Results: The presence of cancerou s tissue, as indicated by MIBI uptake, is a prerequisite for the accumulati on of MIVE by the breast tumors. There was no statistically significant cor relation between the MIBI and MIVE tumor uptake ratios. However, the latter correlate well with the presence of ER, as determined by an in vitro assay . Conclusion: MIVE scans add unique information concerning the tumor ER sta tus in breast cancer patients, which could contribute to a better character ization of the tumor and aid in the selection of the most appropriate treat ment protocol.