WEB Vetnews May 2015

Lead Article I Hoofartikel

The practical application of electron

radiotherapy as a cancer treatment for dogs and cats

Dr Georgina Crewe

Cancer is considered to be the leading cause of death in geriatric patients. These days our companion animals, like us, live longer than previous generations. This is due to advances in nutrition, infectious disease control, oncology treatments and specialist surgeries being available. Cancer is described as a disease of ageing and/or inflammation. Oncologists in the US estimate that 50 percent of geriatric dogs and 33 percent of geriatric cats will die of cancer.

T his article is a brief, It covers the normal cell, damage to the DNA, change into a mutant cancer cell, leading to uncontrolled mitosis, eventually forming a clump of cancer cells and finally radiotherapy as one of the options for treatment. The DNA is the same in every cell in each individual’s body. Certain genes are “switched on/off” so, although both liver and skin cells have the same DNA, they have different shapes and function. Normal cells become cancerous when their genetic control (tumour suppressor genes) becomes damaged and the cells divide out of control. These cancerous cells also do not respond to the process of cell suicide (apoptosis) and the clump of damaged cells grows larger. Sometimes one or more of these cancer cells travel via the lymph or the blood vessels to other areas of the body and colonise the new tissue, referred to as metastasis. The pain that is caused by the clump incomplete explanation of a complex subject.

of cancer cells is due to pressure on the nearby nerve endings. It can range from irritation to excruciating pain, depending in the cancer’s location and the rate of mitosis. Different cells in the body have

Exponential rate of growth in two months, with major increase in pain.

the cancer might recur. Surgery is the direct removal of the tumour. Chemotherapy works by exposing the cells with mutant DNA to chemo-toxic drugs during mitosis and likewise radiation using electrons. The potential cancer cells can lie dormant from months to years. Remission is that period in the patient’s life during which the cancer does not recur. This article will focus on electron radiation therapy. The practical application of electron radiotherapy. Linear accelerator radiation machines cost R30 million and produce electrons or photons. Electrons penetrate the

different rates of innate mitosis but, if the tumour suppressor gene is damaged, these cells increase their mitotic activity uncontrollably and the tumour grows alarmingly. Cancer can grow in one place and just increase in size and/or grow and metastasise in other organs. There are three basic forms of therapy for treating cancerous growths with many variations. The treatments are; surgery, chemotherapy and radiation. They can be used as single therapies, or in conjunction with each other. All cancer treatments try to remove every cancerous cell; if any remain

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