At CVS our oncologists' goal is to empower our patients and their families to win the fight against cancer while enhancing quality of life. We offer innovative treatment options and treat the 'whole patient' through a combination of surgical, medical, radiological, nutritional, physical, and supportive options, and do so in a compassionate, caring environment that encourages active participation in the management of the pet's disease.


Gregory Ogilvie, DVM

Diplomates American College of Veterinary Internal Medicine (Specialties of Internal Medicine, Oncology), European College of Veterinary Internal Medicine (Oncology)


Dr. Ogilvie is director of the Angel Care Cancer Center at California Veterinary Specialists and president of the Special Care Foundation for Companion Animals. There, he cares for patients and their families; teaches interns, residents, and veterinary students; and has an active cancer research program. Prior to his move to Southern California,    Dr. Ogilvie was a full tenured professor, internist, head of medical oncology, and director of the Medical Oncology Research Laboratory, Animal Cancer Center at Colorado State University (CSU) from 1987 until 2003. During this 16 year period at CSU, he also spent one year on sabbatical teaching and developing new, innovative cancer therapies at the medical school and the Laboratoire Nutrition, Croisance et Cancer at the Université François Rabelais in Tours France.


Upon receiving his Doctor of Veterinary Medicine (DVM) from Colorado State University, Dr. Ogilvie established a private practice in Connecticut before completing a residency at Tufts University/Angell Memorial Animal Hospital. From there he joined the faculty as a professor at the University of Illinois before moving on to his professorship in Colorado. Dr. Ogilvie is board certified in both the specialties of both internal medicine and oncology by the American College of Veterinary Internal Medicine and in oncology. He is a Founding Diplomate of the European College of Veterinary Internal Medicine, Specialty of Oncology.


Dr. Ogilvie is co author with Dr. Antony Moore of three books, Managing the Veterinary Cancer Patient (Veterinary Learning Systems, 1995, in English, French and Japanese), Feline Oncology: Compassionate Care for Cats with Cancer (Veterinary Learning Systems, 2001 in English and Japanese) and Managing the Canine Cancer Patient: A Practical Guide to Compassionate Care(Veterinary Learning Systems, 2006 in English, Spanish and Japanese).  He has written over 200 scientific articles and chapters, as well as over 120 scientific abstracts and posters. He has been awarded two international patents, over 10 million dollars in research grants and endowments as a principal or co-investigator, and is the recipient of many awards including: the Arnold O. Beckman Research Award, the Beecham Research Award, the Purina Small Animal Research Award, the Scheidy Memorial Research Award and the AVMA/American Kennel Club Award.


Dr. Ogilvie has lectured on his love of the practice of veterinary medicine and oncology to many thousands of students, veterinarians, physicians and scientists in Africa, Australia, New Zealand, Asia, Europe, the Middle East, South America, and North America. Dr. Ogilvie's teaching skills have also been frequently recognized.  He is the recipient of the Outstanding Teachers Award; two Norden Distinguished Teacher Awards; the MSD Agvet Award for Creativity in Teaching; the SCAVMA Award for "Dedication to Students and the Profession”; and was named Outstanding Companion Animal Speaker for 1999 at the North American Veterinary Conference.


Dr. Ogilvie has also been recognized with: the American Veterinary Medical Association's "Veterinarian of the Year-1995"; the American Animal Hospital Association's "Veterinarian of the Year-1996"; the Colorado Veterinary Medical Association Outstanding Faculty Award-1996; and the 1999 SHARE Human Animal Bond Companion Animal Award. He was awarded the World Small Animal Veterinary Association Hills Award for Excellence in Veterinary Healthcare for the year 2001.



When not caring for pets and people, Dr. Ogilvie enjoys camping, SCUBA diving and long distance cycling. He is also a certified ski instructor. For more than15 years he has volunteered as a counselor at the Sky High Hope Camp for children who have cancer and is on the board of directors for Angel On A Leash to benefit children with cancer. His greatest joys are his daughter Torrie and his wife Karla.

David Proulx, DVM, MSpVM

Diplomate, American College of Veterinary Internal Medicine, Oncology
Diplomate, American College of Veterinary Radiology, Radiation Oncology

Dr. Proulx is head of radiation oncology and a member of Angel Care Cancer Center at California Veterinary Specialists (CVS). His areas of expertise within oncology include both medical and radiation oncology. Prior to joining CVS, Dr. Proulx completed a small animal internship at North Carolina State University. After completing a medical oncology residency in 2003 and a radiation oncology residency in 2005, also at North Carolina State University, he earned board certification as a specialist in medical oncology and radiation oncology. During this training Dr. Proulx also earned a Master's Degree in Specialized Veterinary Medicine.

Dr. Proulx earned his Doctorate of Veterinary Medicine from Tufts University. He holds a Bachelor of Science from Tufts University and lived in Kenya for two years as a Fulbright Scholar.

Bill FitzPatrick, DVM, MS, Diplomate ACVIM (Oncology)
Diplomate, American College of Veterinary Internal Medicine, Oncology

Dr. FitzPatrick joined California Veterinary Specialists as an oncologist at the Angel Care Cancer Center in February of 2013. His practice as an oncologist is the culmination of his longtime dream, beginning first with general veterinarian medicine, adding to that a degree in pharmacological toxicology, and finally completing a residency in oncology. He is dedicated to the diagnosis and treatment of cancer in all animals, and it’s the reason he loves coming to work every day at Angel Care.


His love of animal care began in high school when he worked in a veterinary clinic. This experience developed his passion for animal care and led him to a bachelor’s degree with a double major in biology and Spanish from the University of New Mexico in 1993. He went on to receive a Master’s degree in toxicology from the UNM College of Pharmacy in 1995, where he was involved with cancer and pharmacologic drug studies in humans and animals, and also completed an industrial hygiene project to promote human health safety in the workplace. It was during this time while collaborating with other researchers, including veterinarians, that he developed a passion for oncology and decided to pursue his love for animals by becoming a veterinarian and using his graduate school background in toxicology to improve his ultimate practice.


Dr. FitzPatrick received his doctorate in veterinary medicine from Colorado State University in 1999 and subsequently completed a one-year internship in Connecticut at the New Haven Central Veterinary Hospital. He then spent 5 years practicing as a general veterinarian, providing medical, surgical and emergency medical care for his patients. This gave him a well-rounded background with experience that would benefit him in his dream to become an oncologist. He completed a 3-year oncology residency program in 2009 from Michigan State University, afterwards practicing in Maryland and Massachusetts for three years.


Dr. Fitzpatrick was happy to have the opportunity to join California Veterinary Specialists, in part, because as a native New Mexican, he and his family were able to return to the West and be closer to family and friends, while also enjoying the southern Californian climate. He is very comfortable in southern California as he is fluent in Spanish and has travelled abroad and stayed with host families in Spain and Mexico. One of his favorite trips was visiting the people of Ecuador and traveling to the Galapagos Islands where he saw the vast but unique diversity of plant and animal species.


He is a member of the American Veterinary Medical Association, Southern California Veterinary Medical Association, Veterinary Cancer Society and past member of the Rocky Mountain Society of Toxicology. He has been actively involved in teaching veterinary students as well as interns since his residency program and has been actively involved in clinical research and various cancer trials.


Dr. FitzPatrick enjoys spending time with his family which includes his wife, son, daughter, one boxer/ridgeback dog, and a domestic shorthaired cat. In addition to traveling, he enjoys weight-lifting and has studied martial arts.

David Heller, DVM, MS

Diplomate, American College of Veterinary Internal Medicine (Oncology)

Dr. Heller graduated from Ross University School of Veterinary Medicine in 2002. Following graduation he served as an intern for one year in small animal medicine and surgery at the Veterinary Hospital of the University of Pennsylvania.


Thereafter he went on to complete a 3-year residency and master’s program at the University of Illinois, College of Veterinary Medicine. During this intensive 3-year period, Dr. Heller received training in all aspects of companion animal cancer care, including chemotherapy, radiation therapy, and immunotherapy. Upon completion of his residency and examinations, Dr. Heller attained Diplomate status with the American College of Veterinary Internal Medicine (ACVIM).


Dr. Heller joined the team California Veterinary Specialists in 2014 where he cares for pets with cancer, teaches interns, residents and students while actively developing and evaluating new cancer therapies. Dr. Heller is an active lecturer at local and regional meetings and regularly attends national continuing education meetings. Dr. Heller values the relationships that develop between the patient and family, family veterinarian, and specialist. This relationship serves to benefit the patient in many ways.


Outside of work, Dr. Heller enjoys spending time with his wife, also a veterinarian, and his 2 children. In his spare time, he enjoys traveling, snowboarding, practicing yoga and watching live sports. He is a South Florida native but has grown to love and appreciate the natural beauty and climate of his adopted home in Southern California. The Heller family has two canine members at home, Bambi and Thumper, and a Betta fish, Lucky.