3.0 Tesla vs 1.5 Tesla breast magnetic resonance imaging in newly diagnosed breast cancer patients

Abstract

Aim: To compare 3.0 Tesla (T) vs 1.5T magnetic resonance (MR) imaging systems in newly diagnosed breast cancer patients.

Methods: Upon Institutional Review Board approval, a Health Insurance Portability and Accountability Act-compliant retrospective review of 147 consecutive 3.0T MR examinations and 98 consecutive 1.5T MR examinations in patients with newly diagnosed breast cancer between 7/2009 and 5/2010 was performed. Eleven patients who underwent neoadjuvant chemotherapy in the 3.0T group were excluded. Mammographically occult suspicious lesions (BIRADS Code 4 and 5) additional to the index cancer in the ipsilateral and contralateral breast were identified. Lesion characteristics and pathologic diagnoses were recorded, and results achieved with both systems compared. Statistical significance was analyzed using Fisher's exact test.

Results: In the 3.0T group, 206 suspicious lesions were identified in 55% (75/136) of patients and 96% (198/206) of these lesions were biopsied. In the 1.5T group, 98 suspicious lesions were identified in 53% (52/98) of patients and 90% (88/98) of these lesions were biopsied. Biopsy results yielded additional malignancies in 24% of patients in the 3.0T group vs 14% of patients in the 1.5T group (33/136 vs 14/98, P = 0.07). Average size and histology of the additional cancers was comparable. Of patients who had a suspicious MR imaging study, additional cancers were found in 44% of patients in the 3.0T group vs 27% in the 1.5T group (33/75 vs 14/52, P = 0.06), yielding a higher positive predictive value (PPV) for biopsies performed with the 3.0T system.

Conclusion: 3.0T MR imaging detected more additional malignancies in patients with newly diagnosed breast cancer and yielded a higher PPV for biopsies performed with the 3.0T system.

Keywords: 3 Tesla; Breast; Breast cancer; Breast magnetic resonance imaging; Cancer staging; Magnetic resonance imaging; Outcome; Technical.

Figure 1

3.0Tesla axial T1-weighted fat-suppressed contrast enhanced images in 62-year-old woman with newly diagnosed left breast infiltrating ductal carcinoma show the index cancer with signal void due to biopsy marker (long arrow) in the superior lateral quadrant and a second mammographically occult multicentric lesion shown to represent DCIS (short arrow) in the superior medial quadrant (A), an additional multicentric lesion proven to represent an additional infiltrating ductal carcinoma (arrow) in the inferior lateral quadrant (B), and a suspicious contralateral lesion (arrow) confirmed as a benign papilloma (C).

Figure 2

1.5Tesla axial T1-weighted fat-suppressed contrast enhanced subtraction images in 53-year-old woman with newly diagnosed left breast infiltrating ductal carcinoma show a conglomerate of masses with signal void due to biopsy marker (arrow) in the left superior breast (A), and a mammographically occult rim-enhancing lesion (arrow) 2 cm inferior to the index cancer confirmed as an additional infiltrating ductal carcinoma (B). Note the lower contrast and spatial resolution evident on these images compared to the 3.0Tesla system.