appreciation for vet medicine. It has had some very hard times and some amazing opportunities. One thing I have really learned is that all the owners of pets diagnosed with cancer want as much information as they can. They want to make the best decision for their pet and the best way to do that is with information. The Internet can be a scary place, especially when looking up things like cancer. I found a web site that has a lot of good information it is www.caninecancer.com I pulled some information from it called Cancer101 I thought it might help with some of the basic questions. Most importantly talk to your Vet.
What is Cancer?Dog cancer, like human cancer, is the uncontrolled growth of cells on or within the
body. Although there are many types of cancer, they all start because of
out-of-control growth of abnormal cells. Normal body cells grow, divide, and die in an
orderly fashion. During the early years of a dog's life, normal cells divide more rapidly
until the dog becomes an adult. After that, cells in most parts of the body divide only
to replace worn-out or dying cells and to repair injuries. Because cancer cells
continue to grow and divide, they are different from normal cells. Instead of dying,
they outlive normal cells and continue to form new abnormal cells.
Cancer cells develop because of damage to DNA. This substance is in every cell and
directs all activities. Most of the time when DNA becomes damaged the body is able
to repair it. In cancer cells, the damaged DNA is not repaired. Dogs can inherit
damaged DNA, which accounts for inherited cancers. More often, though, a dog's
DNA becomes damaged by exposure to something in the environment, like smoke,
pesticides or other carcinogens.
Cancerous tumors can spread to other parts of the body where they begin to grow
and replace normal tissue. This process is called metastasis. For example, breast
cancer that spreads to the liver is still called breast cancer, not liver cancer.
Regardless of where a cancer may spread, however, it is always named for the place
it began.
Not all tumors are cancerous. Benign (noncancerous) tumors do not spread
(metastasize) to other parts of the body and, with very rare exceptions, are not life
threatening.
Different types of cancer can behave very differently. For example, bone cancer and breast cancer are very different diseases.
They grow at different rates and respond to different treatments. That is why dogs with cancer need treatment that is aimed at
their particular kind of cancer.
Cancer rates increase in dogs with age. It is the leading cause of death in dogs over 10 years.
DiagnosisIf cancer is suspected in your dog, a veterinarian may order x-rays, blood tests, ultrasounds. A biopsy (the removal of a piece
of tissue) is frequently performed for confirmation that cancer exists and to determine the level of severity from benign to
aggressively malignant (called grading).
PreventionWe do not know how dogs get cancer most of the time. There are many types of cancer and many possible causes of cancer
(chemicals in our environment, sun exposure, assorted viruses and infections). There are important genetic factors as well.
Feeding your dog a healthy diet and keeping them away from known carcinogens will help. Spaying or neutering your dog will
also reduce their risk for developing certain cancers.
TreatmentEach diagnosis of cancer requires individual care and treatment planning. Conventional treatment may include a combination
of treatment therapies such as surgery, chemotherapy, radiation, cryosurgery (freezing), hyperthermia (heating) or
immunotherapy.
Once diagnosed, your veterinarian will discuss the best treatment option(s) for your dog. In some instances, your veterinarian
may refer you to a board-certified oncologist (cancer specialist) depending upon the recommended course of treatment. It
never hurts to get a second opinion and to research clinical trials for which you dog may be eligible.
PrognosisTreatment success depends upon the type and extent of the cancer, as well as the aggressiveness of therapy. Some cancers
can be cured and almost all patients can be helped to some degree.
Another critical point is to understand exactly what is meant when data on efficacy of treatment is presented. Useful terms
include:
Median - this is used in the context of survival, a median survival of three months means that 50% of the animals are alive at
three months, but 50% have died. It does not give you any information of the range of survival of individuals from within the
group. For example, individual animals may have survived for only a day to several years. A median survival is very useful to
allow comparison between different types of treatment.
Survival means just that: how long an animal stayed alive, usually from time of diagnosis, but it could also mean from time of
treatment, or from time the owner first noticed signs of a problem. It does not give you any information on what the animal's
quality of life was during that time.
Progression free survival is the time the animal survived without progression of the clinical signs. This gives you a better idea
of the quality of life.
Common Cancer TermsCancer: any malignant, cellular tumor; cancers are divided into two broad categories of carcinoma and sarcomas.
Neoplasm: an abnormal new growth of tissue in animals or plants; a tumor
Tumor: 1.) a swelling; a cardinal sign of inflammation. 2.) neoplasm: a new growth of tissue in which cell multiplication is
uncontrolled and progressive.
Benign tumor: one lacking the properties of invasion and metastasis and showing a lesser degree of abnormal cellularity than
do malignant tumors. These are usually surrounded by a fibrous capsule.
Malignant tumor: has the properties of invasion and metastasis and displays cells with widely varying characteristics
Carcinoma: a malignant growth made up of epithelial cells tending to infiltrate surrounding tissues and gives rise to
metastases.
Sarcoma: a malignant tumor originating from connective tissue or blood or lymphatic tissues.
Metastasize: spread throughout the body, of cancer cells
Growth: can refer to any kind of an abnormal increase in size of tissue
Lump: can be a growth or fluid filled cyst or any structure raising above the normal surface of a tissue plane.
