Our blck lab, Andy had a mast cell tumor removed in 2011. Because this type of tumor tends to recur, our vet put Andy on a regimen of nutritional supplements that help to prevent the recurrence of these malignant tumors. Unfortunately these supplements are not inexpensive but, fortunately, PetPlan covers them! Andy's doing great but sees the vet for biopsies as lumps appear. PetPlan covers those, too.