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tvpjournal.com | January/February 2016 | Today's VeTerinary PracTice elemenTs oF oncology Peer reviewed 55 • splitting a cyclophosphamide bolus dose into an oral dose given over 3 to 4 days 18 • administering cyclophosphamide early in the day (to avoid overnight retention of the metabolite in the bladder) • Providing large amounts of fresh water, and allowing frequent opportunities to empty the bladder. Hand–Foot Syndrome chemotherapy pain due to hand–foot syndrome (HFs) or palmar–plantar dysesthesia is well documented in human patients following administration of chemotherapy drugs, including doxorubicin, capecitabine, and 5-fuorouracil. 19-22 HFs is characterized by diffuse erythema, swelling, and pain of the palmar and plantar surfaces of the hands, feet, or paws. 19-23 While uncommon in veterinary medicine, HFs was reported as the dose-limiting toxicity in dogs treated with a liposomal formulation of doxorubicin. 20-22 This toxicity was reduced, but not completely eliminated, by co-administration of pyridoxine, which allowed fewer treatment delays and dose reductions and a higher cumulative dose compared with placebo-treated controls. 23 Hand–Foot Skin Reaction a similar reaction termed hand–foot skin reaction (HFsr) has been reported in humans following treatment with small molecule inhibitors, including sunitinib. 19,24-25 HFsr is similar to HFs , but the lesions are histologically distinct and confned to pressure points. HFsr has not been reported in dogs treated with the small molecule inhibitors toceranib (an Fda-approved veterinary drug nearly identical in structure to sunitinib) or masitinib. 26-29 as liposomal formulations of chemotherapy drugs and novel targeted chemotherapy agents become available in veterinary oncology, this side effect may be detected. CHRONIC CANCER PAIN & PALLIATIVE TREATMENT many veterinary patients with cancer are unable to receive defnitive treatment; this may be due to metastatic disease at time of diagnosis, other life- limiting comorbidities, or lack of owner fnances (Figure 1). The central focus of palliative treatment is relief of pain and suffering. although most patients undergoing palliative treatment for their cancer will ultimately succumb to the disease, their quality of life can still be greatly improved for a period of time. Palliative treatment includes administration of pain medications and, potentially, various treatment modalities for the cancer itself. Palliative Surgery in certain clinical situations, cancer that causes discomfort and/or pain may require surgical palliation. it is important for the practitioner to think about the whole patient and disease process when considering this treatment modality as a method of palliation. The frst dictum of palliative medicine is the overriding goal of decreasing the patient's pain. in the osteosarcoma case described on page 50, surgical amputation alone could be considered a palliative procedure; within 24 hours the patient felt better than it had prior to surgery. The distinction between palliation and defnitive treatment in this case was the pursuit of chemotherapy, which created the potential for more side effects but improved long-term survival. gilson provides an excellent review of the indications and pitfalls of surgical cancer palliation. 30 continuous pain management using nsaids, opioids, gabapentin, and amantadine is necessary in the postoperative period and may be needed for continued palliation when additional therapies are not pursued. Palliative Radiation What distinguishes palliative-intent from defnitive-intent radiation therapy are goals of treatment, total dose of radiation delivered, and size of each fraction delivered. Palliative radiation therapy is designed to relieve clinical signs of pain and discomfort and avoid the potential for adverse side effects. Indications in patients in which defnitive surgery and radiation therapy are not possible, palliative radiation therapy should be considered. Patients with gross soft tissue sarcomas, mast cell tumors, histiocytic sarcomas, and nasal tumors are all viable candidates for palliative radiation therapy. Palliative radiation therapy is especially helpful for relieving pain that results from tumors that invade bone or other areas of the body. Pain sparing occurs as a result of the release of various anti-infammatory cytokines at the treatment site,