The BSVP regional meeting at Bristol was held on Wednesday, 3rd June. The topic this time was Immunohistochemical proliferation markers in Veterinary diagnostic pathology. Sean Haugland and Tim Scase based their discussion on Ki67 and their experiences with its use, interpretation and potential pitfalls in mast cell tumours. Difficulties in interpretation of definitely positive cells and when inflammation is present gave us all a better understanding of the use of this marker when attempting to provide prognostic information for these tumours. Sean also gave an overview of MCM proteins which may serve as more accurate markers of proliferation. There was brief time left for attendees to present cases of interest including a dual T/B positive lymphoma in a dog and a cytokeratin positive melanoma in the 3rd eyelid of a dog. The next meeting is Wednesday, 12th August when the subject will be Bone Marrow.