<prompt> Mantle cell lymphomas are positive for all of the following, except -CD 23CD 20CD 5CD 43  <response>: Mantle cell lymphomas express high levels of cyclin D1.Most tumours also express CD19,CD20 and moderately high levels of surface Ig.It is usually CD5 positive and CD 23 negetive, which helps to distinguish it from CLLSLL. Reference : Robbins and Cotran Pathologic basis of disease.South Asia Edition volume 1.page no. 603 