Cancer in Pets

October 2, 2016

A cancer is a tissue mass characterized by persistent, excessive, and disorganized cell growth that is unresponsive to normal control mechanisms.  It is the unrestrained growth of cells that destroy normal tissues and body parts.

Cancer is the number one natural cause of death in senior cats and dogs. Cancer accounts for nearly 50% of deaths each year in older pets.  Why this happens, in most cases, is not yet known.  As a result of improved owner and veterinary care, pets are living much longer and thus are more susceptible to the diseases of old age, among them, cancer.

Although cancer is the leading cause of death in senior patients, it is also a very manageable disease, and while there is no cure, remission can be achieved.

Glossary of Terms Used in Cancer Medicine:

• Tumor: refers to a mass, which may be either benign or malignant.
• Benign Tumors: These types of tumors have many normal growth characteristics.  They do not spread or invade other organs.  They may however, compress normal organs or tissues by virtue of their size.  Surgical removal is usually curative.
• Malignant Tumors: These tumors often have rapid, irregular growth characteristics.  These tumors can invade normal tissues in the local area from which they arise, as well as spread to other tissues (especially the lymph nodes, liver, and lungs).  New tumors can grow at these secondary sites, eventually leading to death.
• Metastasis: The process whereby a tumor spreads to secondary sites.  These new tumors are referred to as metastatic disease, or metastases.
• Oncology: Refers to the study of tumors, including their biologic behavior and treatment.
• Tumor response: This denotes a decrease in tumor size (often called tumor burden) over time.
• Remission:  Remission means that the tumor has responded to treatment and can no longer be detected.
  Remission time is the length of time during which the growth of the tumor is under control.

Treatment of cancer in animals can often result in fairly lengthy remission times with an excellent quality of life.  However, for many types of cancer their return is inevitable.  This fact must be contemplated and discussed before making the decision to treat an animal for cancer. Having reasonable and accurate expectations will help provide a more positive experience for all those involved.