In vivo detectability of a signal (tCho) from choline containing molecules at ~3.2 ppm by MR spectroscopy (MRS) can be useful as a biomarker for malignancy. tCho has also been observed in benign, normal, and lactating breast, therefore quantitation is vital. The aim is to assess whether tCho detectability can differentiate between benign and malignant breast disease and to implement internal water-referenced choline quantitation at 3T.
Women with histologically confirmed breast cancer or suspicious features were identified either at MDT or following referral for clinical breast MRI and recruited following informed consent. Studies were performed on 3T Philips Achieva (the Netherlands). Contrast-enhanced MRI localised the region for point-resolved spectroscopy (PRESS) evaluation. Spectral processing was performed with jMRUI. The choline concentration was determined using the unsuppressed intravoxel water resonance as a reference. tCho detectability and choline concentration were correlated with known pathological information. Results were analysed by JKPB.
Nine participants (age range, 38 to 73 years) were successfully examined. tCho was detected at ~3.2 ppm in four of nine lesions (lesion size, 0.8 to 7.0 cm; mean, 3.0 cm), providing a sensitivity and specificity of 67% and 100%, respectively. The two quantitative values of 2.13 and 5.59 mmol/kg are consistent with previously reported findings.
MRS is a non-invasive and non-ionising means of analysing lesion metabolism as an adjunct to clinical MRI. Whilst potentially useful for differentiating between benign and malignant breast diseases, implementation is challenging. Using clinical 3T systems, internal water referencing can successfully quantify choline in patients with breast cancer.