Images of estrogen-receptor-positive breast tumors produced by estradiol labeled with iodine I 123 at 16 alpha.

OBJECTIVE

To examine the suitability of estradiol labeled with iodine I 123 at 16 alpha for imaging estrogen-receptor-positive breast carcinoma using imaging instrumentation that is widely available.

DESIGN

Single-photon emission computed tomographic imaging survey of 29 women with suspected primary or expected recurrent breast carcinoma.

SETTING

University-based referral center.

PARTICIPANTS

Twenty-nine women undergoing diagnosis for primary or recurrent breast carcinoma. Selection was voluntary.

MAIN OUTCOME MEASURE: Qualitative imaging study designed to provide tomographic data of radioligand retention and descriptive data of imaging results.

RESULTS

Single-photon emission computed tomographic imaging using 123I-estradiol at 16 alpha was performed for patients with breast carcinoma. Independent readers, without knowledge of receptor status or proven disease, interpreted the films. Scintigraphic detection was most noteworthy in patients with chest wall tumors and inflammatory breast cancer. Agreement between readers was 98% for true-negative readings and 94% for true-positive readings, but only 60% for false-positive and false-negative film readings.

CONCLUSIONS

Our results indicated that areas shown on imaging were also found to have estrogen-receptor activity and that radioligand accumulation can occur with low frequency in some surgically explored tissue. Radioligand imaging with 16 alpha-123I-estradiol can locate estrogen-receptor-positive breast tumors, including some that may be difficult to detect using conventional diagnostic imaging.