Comparing thallium-201 spect mammoscintigraphy and ultrasonography to detect breast cancer in mammographical dense breasts

The aim of our study was to compare the usefulness of thallium-201 (T1-201) single photon emission computed tomography (SPECT) mammoscintigraphy and ultrasonography to detect breast cancer in mammographical dense breasts. This study included 32 Taiwanese female patients with indeterminate mammographic probability of malignancy due to mammographical dense breasts. Both T1-201 SPECT mammoscintigraphy and ultrasonography were performed for each patient. Then, all of the 32 breast masses undervent biopsies or operations to obtain finally pathological diagnoses. Based on the finally pathological diagnoses, 24 masses were breast cancer and 8 masses were benign breast tumors among the 32 patients. Twenty-two cancers and one benign tumor had positive T1-201 SPECT mammoscintigraphic findings. The sensitivity, specificity, and accuracy were 92%, 88%, and 91%. Twenty-two cancers and 5 benign tumors had positive ultrasonographic findings. The sensitivity, specificity, and accuracy were 92%, 38%, and 78%, respectively. To detect breast cancer in patients with non-diagnostic mammogram because of mammographically dense breasts, T1-201 SPECT mammoscintigraphy and ultrasonography have the same sensitivity to screen breast masses. However, due to its higher specificity, T1-201 SPECT mammoscintigraphy should be useful to confirm the ultrasonographic findings.