Biopsy in Dogs
Dr. Cathy Reese
Biopsy is the term used to describe the procedure in which a sample of tissue is taken for microscopic analysis. This procedure is generally invasive, requiring general anesthesia. Blood and urine tests may be necessary to help determine the underlying cause of the illness or as a general health screen prior to anesthesia.
Depending on the organ or tissue to be biopsied, various techniques may be used. If a small piece of tissue is all that is needed, an "incisional biopsy" can be performed. In some situations, whole tumors may be removed and submitted, referred to as an "excisional biopsy".
When a tumor is removed, the outer margins of the tissue that has been surgically removed should be evaluated microscopically to determine if the entire mass was successfully removed.
The biopsy results will tell what type of tumor or disease process is occurring and help the veterinarian decide what therapy is best for your pet.
Anytime a pet is ill, the veterinarian will ask many questions to develop a complete history of the progression of the problem. These questions will include your pet's age, when the problem began, how the problem has progressed over time and what treatments you have tried and with what results.
After obtaining a complete history, the veterinarian will likely perform a complete physical examination of your pet, including checking for a fever, palpating (feeling) your pet's abdomen and listening to his heart and lungs.
Radiographs (x-rays) may be taken to help identify the problem. Tumors, if present, can often be seen on x-rays.
Ultrasound (sonogram) may also be done to identify abnormalities in the structure of the abdominal or thoracic organs.
More advanced imaging techniques, such at CT scan (computed tomography) or MRI (Magnetic Resonance Imaging) are available at some specialty veterinary hospitals.
Depending on the organ that needs to be biopsied, there are a variety of ways to perform the biopsy.
Exploratory abdominal surgery. During surgery, incisional biopsies can be taken of multiple organs at the same time.
Endoscopy. Using a fiberoptic scope as a guide, small pieces of tissue can be taken from the nasal cavity, stomach, intestine or colon. This procedure requires general anesthesia but does not involve a surgical incision.
Skin lesions and tumors can be biopsied using a variety of biopsy needles and instruments.
Bone and bone marrow can be biopsied using special needles.
After a biopsy, the pet should be rested and restricted from activity for about 1-2 weeks to allow the biopsy site to heal. If your pet licks or chews at his incision, an Elizabethan collar may be necessary to keep him from opening or infecting the incision.
Biopsy results are typically available within about one week. Based on the findings, treatment recommendations or additional tests may be suggested.