Cancer is a major cause of death in older pet dogs and cats. Cancer is most often a disease of older age. As our dogs and cats maintain their health better and live to older ages, they are at risk for cancer development. With more than 54 million pet dogs in the United States, cancer is a growing challenge to pet animals, their families, and to veterinarians. Cancer remains a major cause of suffering and death in people as well, taking the lives of more than half a million people each year in the United States. Our mission is to change this. As veterinarians, it is obvious that our work is aimed at helping our canine and feline companions. Our work is also aimed at benefiting human cancer patients. This is possible because some specific forms of naturally-occurring cancer in pet dogs closely mimic that same form of cancer in humans. Therefore, information gained from the study of cancer in animals provides important information in the fight against human cancer.
Cancer Research to Benefit Pet Animals and People
The Purdue Comparative Oncology Program (PCOP) in the School of Veterinary Medicine at Purdue University was formed in 1979 with the goal of improving the outlook for pet animals and humans with cancer. The program: (1) provides compassionate care for more than 1,000 pet animals with cancer each year at the Purdue University Veterinary Teaching Hospital, (2) generates important information that is leading to clinical trials of new therapies in humans with cancer and improved care for pet animals with cancer, and (3) educates veterinary students, veterinary technician students, and veterinary oncology residents. A tremendous opportunity exists for the comparative nature of the work because specific forms of naturally-occurring cancer in pet animals very closely mimic those same forms of cancer in humans. Therefore, when a new successful approach to prevent or treat cancer in pet animals is identified, there is clear justification to evaluate this approach in humans.
The activities of the PCOP are organized in three major program areas: (1) urologic oncology, (2) skeletal oncology, and (3) residency training/clinical activities.
The Urologic Oncology Program
Purdue University School of Veterinary Medicine Advancing the knowledge and treatment of urinary bladder cancer
Urologic cancers, specifically prostate cancer and urinary bladder cancer are a major focus of investigation in the PCOP. There is great need to develop better strategies to prevent or to treat bladder and prostate cancer in humans, as well as in our pet animals.
Urinary Bladder Cancer
Currently, more than 600,000 people in the United States have urinary bladder cancer. This disease detracts from quality of life and takes the lives of more than 14,000 people each year. Most deaths are due to the more aggressive form of bladder cancer, high grade, invasive transitional cell carcinoma (TCC). Fortunately, many people with bladder cancer have a less aggressive form of the disease (lower grade, superficial bladder cancer) that is usually not life threatening. Urinary bladder cancer also affects pet dogs. Unfortunately, most dogs with bladder cancer have intermediate to high grade invasive TCC. Urinary obstruction and spread of the cancer has taken the lives of most dogs with TCC. As summarized below, however, we are making progress against this disease. Studies have allowed us to learn some of causes of TCC in dogs, and this can lead to strategies to prevent the disease in the future. More effective ways to treat TCC in dogs have been identified. These new treatment approaches have extended survival and improved the quality of life of dogs with TCC, AND these studies in pet dogs have resulted in clinical trials in humans with bladder cancer.
Purdue University School of Veterinary Medicine Advancing the knowledge and treatment of bone cancer
Bone cancers, including those cancers that arise in bone (primary bone tumors) and cancers that spread to bone (bone metastases), are a major focus area of investigation in the Purdue Comparative Oncology Program. There is great need to improve survival and enhance the quality of life of people and pet dogs with bone cancer.
Osteosarcoma is the most common primary bone tumor in man, most commonly occurring in children and young adults. Osteosarcoma is also the most common bone tumor in the dog with approximately 10,000 new cases diagnosed each year in the United States. Throughout the years, PCOP has been involved in the evaluation of novel therapies against osteosarcoma which have been instrumental in the study of these agents in children with osteosarcoma. A recent study by PCOP investigators has uncovered possible factors that contribute to the risk of osteosarcoma in dogs.
Studies indicate a high prevalence of bone metastases in dogs with cancer. Carcinomas of breast, lung, and prostate are the most frequently reported primary tumors in dogs with bone metastases. Similar to man, bone metastases in dogs most often affect the spine, ribs, pelvis, and the upper limbs. In humans, bone metastases far outnumber primary bone tumors. Fifty percent of women dying of breast cancer have bone metastases and the skeleton is the first site of metastasis in over 80% of men that relapse after radical prostatectomy for prostate cancer. Understanding the mechanisms of why some cancers preferentially spread to bone is necessary for developing effective bone-targeted strategies which are desperately needed in the clinic.
