Academic Radiology reports that breast-specific gamma imaging (BSGI) provides higher sensitivity for detection of ductal carcinoma in situ (DCIS) than mammography or MRI and can reliably detect small, sub-centimeter lesions, based on the results of a study at The George Washington University Medical Center.
BSGI is an increasingly utilized adjunct imaging modality in diagnosing breast cancer, and effective in detecting mammographically suspicious microcalcifications. In the GWU study, Dr. Rachel Brem and colleagues demonstrate the efficacy of BSGI in finding otherwise mammographically occult cancers and in determining the true extent of disease. Specifically, BSGI detected low-grade DCIS and identified several lesions <4 mm not found on mammography or MRI.
"We believe this is an important contribution to the literature in that it compares different imaging modalities for the diagnosis of DCIS, a timely issue," said Brem in the journal’s article.
The findings indicate that the pathologic tumor size of the DCIS ranged from 2-21 millimeters. Of the 22 cases of biopsy-proven DCIS in 20 women, 91 percent were detected with BSGI, 82 percent were detected with mammography, and 88 percent were detected with MRI. BSGI had the highest sensitivity for the detection of DCIS. In contrast, mammography is unreliable in predicting the physical presence and extent of DCIS. MRIs have the potential to overestimate DCIS extent in as many as 50 percent of cases, and often cannot distinguish benign from malignant lesions, high-grade from low-grade DCIS, or detect an invasive component concurrent with the DCIS.
Patients had BSGI with the Dilon 6800, a high-resolution, small-field-of-view gamma camera with standard mammographic views.