Role of choline as a biomarker of cell proliferation to differentiate HER2/neu positive and negative breast cancers patients

Introduction: Overexpression and amplification of HER2/neu proteins have been found to be associated with the aggressive behaviour in breast cancers. This molecular marker is important for guiding treatment choices of breast cancer patients and is over expressed in about 20% of the cases (1). HER2/neu positive lesions show poor prognosis and its overexpression is associated with the increased disease recurrence. Several in-vivo and in-vitro MR spectroscopy studies demonstrated that alterations in the levels of choline-containing metabolites like phosphocholine (PCho), glycerophosphocholine (GPC), and choline are associated with the malignant transformation of breast cancer. However, only limited literature correlating MRI and MRS characteristics of lesions with the expression of HER2/neu in breast cancer patients with contradictory results are available. Tse et al. (2) and Agrawal et al. (3) reported higher choline detection rate in HER-2/neu positive patients compared to Her-2/neu negative patients. However, a recent study reported limited role of in-vivo MRS in characterizing HER2/neu overexpression in breast cancer. An in-vitro proton MRS study documented that overexpression of HER2/neu is associated with the increased levels of tCho in a tumor cell line (4). Thus, the objective of the present study was to compare and correlate the tCho concentration and tumor volume with the Her2neu positive and negative status of breast cancer patients