Quantity of life is meaningless without quality.
Because quality issues are vague and changeable, it is easy to focus instead on quantity because that is a specific, well-defined goal. It is important to keep these two factors in balance. Your veterinarian should provide perspective and be objective and well-informed about cancer, it's treatment, and how it is likely to affect your pet. On the other hand, you know your pet the best? The veterinary staff sees your pet for perhaps a few hours a week in a hospital setting, while you and your family are with your pet at home on a daily basis.