Role of Magnetic Resonance Spectroscopy Using Choline Peak as A Malignancy Marker In Diagnosis Of Suspicious Breast Lesions (BIRADS III and IV)

Abstract

Role of Magnetic Resonance Spectroscopy Using CholinePeak as A Malignancy Marker In Background: BIRADS III and IV lesions are a clinical dilemma as they need either follow up or biopsy. Since 80% of lesions determined in the breast are benign upon biopsy, we need new methods for evaluation of this lesions to avoid unnecessarybreast interventions .MR spectroscopy is a promising new technique which can be used to improve the diagnosis of breast lesions classified according to BIRADS category .The diagnostic value of H-MRS is typically based on the elevation of choline compounds which are the markers of malignancy and aid in the differentiationbetween benign and malignant breast lesions .Aim of the Work: To assess the diagnostic value of MR spectroscopy using cholinepeak as a malignancy marker in diagnosis of suspicious breast lesions categorized bymammography or sonomamography as (BIRADS III, IV) and correlation withavailable histopathological findings, clinical data or follow up.Material and Methods: In this study 35 female patients classified as BIRADS III & IV by sono-mammography (Sono-MX) or sonography were examined by conventional dynamic MRI and proton MR spectroscopy using a magnet (1.5 Tesla).Single voxel technique after adequate shimming was used.Results: 18 out of 35 patients had BIRADS III Lesions and 17 were BIRADS IV .25lesions were benign (71.4%) (7 of them were BIRADS IV lesions and 18 wereBIRADS III lesions), and 10 were malignant (28.6%) (all of them BIRADS IVlesions). A choline peak was present in 13 lesions (37.1%) of 35 and in 3 of 18benign lesions. Calculated MR spectroscopy sensitivity was 100 % and specificity 88%. Positive predictive value was 76.9 %, false positive rate was 12.0%, Correctclassification was 91.4%. Conclusion: Breast single MRS can increase the specificity of the conventionaldynamic MRI in evaluating breast lesions classified as (BIRADS III and BIRADS IV)and hence reduced the number of unnecessary biopsies.Key words: MR spectroscopy, Choline, Suspicious, BIRADS III and IV.