The removal of masses during surgery and their subsequent histologic evaluation poses challenges for the veterinary surgeon and pathologist alike. For the surgeon, removal of a potentially malignant neoplasm in its entirety can be at odds with a cosmetic and anatomic closure of the surgical site. For the pathologist, interpretation of surgical margins is confounded by tissue shrinkage and other post-fixation artifacts. In this report, a previously undescribed technique for the removal of canine cutaneous masses en bloc is presented in the context of a clinical case presentation. The application of the ‘tumor sandwich’ technique and its ability to facilitate mass removal and margin preservation is discussed in detail. The pathology of canine cutaneous vascular tumors is also briefly reviewed.