The canine spleen and internal lymph nodes are frequently affected by blood-borne cancer. Flow cytometry (FC) can provide key diagnostic and prognostic information for canine cancer and is a rapid and objective tool while also minimally invasive to the patient. However, the methodology is currently limited by the lack of tissue-specific reference intervals (i.e., what is considered “normal”), and published data on the canine spleen and internal lymph nodes is lacking. In light of these knowledge gaps, the investigators will examine the benefits of flow cytometry in the evaluation of dogs with blood-borne cancer that commonly affects the spleen and internal lymph nodes. Performing flow cytometry on tissues from canine patients presenting to University of Minnesota Veterinary Medical Center will allow identification of tissue- specific reference intervals. The findings may provide for accurate and reliable diagnosis of blood-borne disease, including cancer, in dogs.