Breast-specific gamma imaging effective for cancer detection in dense and nondense breasts

Breast-specific gamma imaging (BSGI) has high sensitivities for breast cancer detection in women with dense and nondense breasts, according to an article published in the February issue of the American Journal of Roentgenology.

Sensitivity in mammography screening significantly declines when imaging dense breasts, making detection of breast cancer more difficult in this demographic of patients that already possesses a strong risk factor for the disease. BSGI, an adjunct modality for breast imaging, has 96.4 percent sensitivity for breast cancer detection. Lauren R. Rechtman, MA, of George Washington University in Washington, D.C, lead author of the study, and colleagues compared the sensitivity of BSGI in detecting breast cancers in women with dense versus nondense breasts.

The study was comprised of 341 consecutive patients with newly diagnosed biopsy-proven breast cancer who underwent BSGI before surgical excision from 2004 to 2009. The researchers obtained breast density information from the mammography reports for analysis. BSGI examinations were positive in 331 of the 347 biopsy-proven breast cancers, producing an overall sensitivity of 95.4 percent. There were 272 invasive cancers and 263 of them were positive on BSGI. Sixty-nine of the 76 ductal carcinoma in situ were positive on BSGI.

Of the patients examined, 141 breasts were nondense and 206 were dense. The mean age of women with dense breasts was 53.4 years and the mean age of women with nondense breasts was 58.1 years. Cancers in 136 of the 141 women with nondense breasts and in 194 of the 206 women with nondense breasts were positive for respective sensitivities of 96.5 and 94.7 percent. Sixteen breast cancers were not detected by BSGI, five of which were in women with nondense breasts and 11 in women with dense breasts. There was no significant difference between BSGI cancer detection and breast density.

“The availability of BSGI now offers those women who cannot or will not undergo MRI an alternative for physiologic imaging,” wrote Rechtman and colleagues. “The addition of BSGI expands our armamentarium of imaging modalities for improved detection of breast cancer.”