Few things seem to strike more fear into the hearts of pet parents than hearing these words from your veterinarian: “I’m recommending a biopsy.” The fact is, many pets at some point in their lives will undergo a biopsy procedure.
As pets get older, their chances of developing abnormal growths and/or cancer increases. A biopsy is used to determine what abnormalities may be cancerous and which are benign (non-cancerous).
What is a Biopsy?
The term “biopsy” refers to the removal of a sample of tissue directly from a specific part of the body – usually from a tumor, the skin, or an organ – and examining the cells that make up that tissue under the microscope. Your veterinarian may recommend a biopsy for anything that looks suspicious: a lump under the skin, a scaly or pigmented area of the skin itself, or a bone or organ that appears abnormal on an x-ray or ultrasound.
Many tissues and organs can be biopsied, including the skin, lymph nodes, liver, kidneys, lungs, spleen, glands (such as the prostate and thyroid), and bone.
How Tissue is Collected and Examined
There are several different biopsy techniques used for collecting tissue and cells. The most common are the punch biopsy, needle core biopsy, wedge biopsy, and excisional (also called “surgical”) biopsy.
Which technique is used is ultimately determined by the specific properties of the area to be biopsied – including location, how easy it is to get to, and the type of tissue being sampled. The condition of the individual pet is also taken into consideration, since some biopsies require general anesthesia.
Punch Biopsy
During this procedure, a tool called a biopsy punch is used to remove a small, deep circle of tissue from either the skin or a growth (also referred to as a “mass”). The skin is then closed with just one suture. This technique is especially good for use on scaly lesions on the surface of the skin, and it’s minimally invasive, requiring only local anesthetic.
Needle Core Biopsy
A needle core biopsy uses a specialized hollow needle instrument to take a long, thin piece of tissue from the center of the mass. It can be used for growths located both on the outside and inside of the body (using imaging technology such as ultrasound to help locate the area to be tested).
The needle core biopsy is often used on pets with skin masses. It is minimally invasive (often done with local anesthesia and/or sedation), and relatively inexpensive. No sutures are required.
Wedge Biopsy
The wedge biopsy (sometimes called an “incisional biopsy”) is more invasive than a punch or core biopsy. It’s used in cases where punch or needle biopsies can’t provide adequate tissue to make a diagnosis.
Wedge biopsies involve the surgical removal of a wedge-shaped piece of tissue from the suspected mass for examination. This type of biopsy is usually recommended for abnormalities in internal organs, and requires general anesthesia. Because this procedure is more involved, some veterinarians may elect to have a wedge biopsy done by a veterinary surgery specialist.
Excisional Biopsy
In an excisional (or surgical) biopsy, the entire mass (rather than just a piece of it) is removed, along with the surrounding tissue. This is done to make sure that all margins of the mass are collected.
Excisional biopsies are used not only to distinguish between cancerous and benign tumors, but they can also differentiate between certain types of cancers. They may also be used to help diagnose a disease (such as liver disease), and to determine that disease’s severity.
Excisional biopsies tend to be the most accurate and informative, but they are also the most invasive. General anesthesia is required for a true mass removal.
What Happens After the Biopsy Procedure?
Once a tissue sample has been collected, it’s placed in a small plastic jar containing formalin, a toxic (and very pungent-smelling) solution derived from formaldehyde. This preserves the individual cells making up the tissue, which essentially provides a “snapshot in time” of the sample for the veterinary pathologist who will be examining it.
The jar is then sent to a lab. There, the tissue is removed from the formalin, covered in wax, and sliced into extremely thin sections. These almost transparent sections are placed onto glass slides and stained with a specialized solution, which helps the pathologist better identify the morphology (specific shape, size, and structure) of the cells within the tissue.
Cell morphology indicates whether the sampled cells are cancerous, and if so, what type of cancer is present. If the cells are not cancerous, and they were taken from an organ such as the liver or kidney, the appearance of these cells can still indicate if disease is present, and if so, how advanced it is.
Once the pathologist has prepared a formal report, the report is sent immediately to the veterinarian who requested the biopsy. The veterinarian may then consult with the pathologist to interpret the results, and in some cases, obtain additional insight to assist with formulating a treatment plan for the pet.
Cytology vs. Biopsy
Sometimes your vet may elect to do a procedure called a fine needle aspirate (or FNA) first, rather than proceed straight to a biopsy. The difference between these two procedures can be somewhat confusing. The FNA is considered to be “aspiration cytology”, which is a much simpler procedure than a biopsy.
With aspiration cytology, the veterinarian inserts a long, thin needle through the pet’s skin directly into the tissue being sampled (usually a skin mass or enlarged lymph node). He or she then repeatedly pumps the plunger in the syringe to suck up as many cells as possible for sampling. These cells are squirted onto a glass microscope slide, then sent to the lab for staining and evaluation by a pathologist. Sedation or anesthesia is usually not required for an FNA.
Cytology is often used to gather preliminary information first. It doesn’t provide as much information as a biopsy, but the results can help your vet determine in which direction to proceed. It can tell the vet if a growth is indeed a tumor, and if so, what family of tumors it might belong to (which will determine what treatment is needed).
With FNA, results are usually available more quickly than with a biopsy. If more specific information is needed after an FNA, your vet may then recommend a biopsy.
Nothing to Fear
Biopsies are no different from any other procedure when it comes to risks vs. benefits. Some pets are not good candidates for biopsy procedures. If a veterinarian suspects a tumor in a place that is not accessible for a biopsy (such as a brain tumor), or if the pet has a bleeding disorder that could result in excessive bleeding during the procedure, the vet may elect to use his or her best guess as to what is causing the problem and treat it accordingly. Fortunately, these cases are rare, and most pets do quite well during biopsy procedures.
It’s also important to note that there are several options available when it comes to managing discomfort during biopsies. In some cases where a pet is not a good candidate for general anesthesia, a combination of a sedative and a local anesthetic may be a better alternative.
One word of advice: when it comes to lumps and bumps, beware the “just watch it” approach. Many types of cancer can be caught in the early stages, and it’s relatively easy to perform a simple biopsy to obtain an accurate diagnosis to determine what treatment, if any, is needed.
Fearing a biopsy for your pet could result in delayed treatment, which can greatly impact his health. It’s always better to know what’s happening and address it head-on than not to know! If your pet ever needs a biopsy, rest assured that your vet will work with you to determine which technique is the safest and most effective for your pet.
Has your pet ever had a biopsy? Please share your story with us in the comments below!
Are Vets in general able to diagnose cancer from a biopsy in their office or must they send it off to a pathologist?
The reason I ask is I recently had a sick cat put to sleep because my Vet called and said he performed a ultrasound and found tumors in the stomach & asked if I wanted him to do a biopsy to see if it was cancer. I said yes, and he called me 2 hours later and said the biopsy results were positive for cancer.
Hi Sandy. First, please accept my deepest condolences on the loss of your kitty. Regarding your question, yes, veterinarians can examine the cells from a biopsy in their office without having to send the sample out to a pathologist. There are benefits to sending it out, including having the cells examined by an experienced pathologist who can tell you exactly what type of cancer is present and what stage it’s likely in. But if you need a diagnosis quickly, most veterinarians can distinguish between cancerous and non-cancerous cells by staining the cells and examining them under a microscope.
Hi,
I recently took my cat to the vets for weight loss and diarrhoea and ultimately left him there for fluids, a scan to take his bloods, the day after it was really difficult to get hold of any one and they told me they were keeping him in because he had been through a lot that day, then the day after that I found out they had taken samples of his lymph node, liver and guts using very fine needles, later on the same day I was told I could collect him and did, I got him home and he was unable to walk correctly or get up any steps, I though this may have been drugs left in his system if they had used any, he was acting like a normal cat when I had took him in. The following day he collapsed and we took him back to the vets were he pass away, the vets suspect that he developed a gut perforation most likely caused by a chronic process (lymphoma or some other cancer) this may have been one hell of an coincidence but I had questioned if it was possible that the needle was miss used and caused this, now I know he was unwell but they have just told me this would no way have been the cause of the gut perforation, would you be so kind to let me know you option.
Kind regards,
Michael, I am so sorry to hear about the loss of your cat, and the traumatic experience that you both went through. 🙁 Although I don’t know all the details, I know the veterinarian should have gotten your consent for any biopsies taken from your cat’s organs, as taking a biopsy from anywhere in the abdomen is much more involved than taking one from a lymph node. That being said, cancers such as lymphoma can cause the gut to perforate. Feline lymphoma could have been the cause of your cat’s weight loss and diarrhea, as well as being able to cause a perforation. Biopsies are generally very safe when performed correctly, so it’s probably unlikely that the biopsy itself could have caused a perforation; however, because we don’t know what technique was used and what, if any, complications could have occurred, it would be very hard to ever know for sure if the perforation was caused by the biopsy. Although very unlikely, it would not be impossible. So sadly, you may never know the answer to that question. 🙁
Please accept my sincere condolences for your loss, and I hope that in time your happy memories of him will outweigh the sadness you feel from losing him so unexpectedly. <3
Thank you for taking the time to reply, it has been most helpful. they told me the specialist identified an area in his guy in particular which looked particularly thickened as well as identifying a very small pocket of free fluid in his abdomen which they attempted to sample but the volume was so small they where unable to…. ultimately I guess they had to take samples before they could do any thing, I spent a lot of money on him when he went in to shock though what they tell me was a condition called ‘septic abdomen’ with his critical state and presumptive diagnosis of a cancerous process being the initial cause they told us the kindest decision was to put him to sleep, if I feel they had a part to play with how quickly he went down hill I would be seeking a discount from the bill, I guess if there is no real way of knowing then I guess I will have to assume they do what they could.
thanks again,
You’re very welcome, and thank you for the update. It certainly sounds like cancer was the probable cause of your kitty’s rapid rapid decline. In both cats and dogs, cancer can cause them to decline very quickly towards the end, and sepsis is often the final blow in the process. When that happens, bacteria from the gut leaks into the abdominal cavity, causing an overwhelming bacterial infection that the body just can’t fight off. Although you ultimately made the best decision in having him put to sleep, I know it doesn’t make it any easier to say goodbye. My deepest sympathies on your loss. 🙁
My little lady is 10.5 and has an ultrasound which showed thickened intestinal walls and enlarged lymph nodes. She is also experiencing chronic vomiting, which raised all our initial concerns and got us to this stage.
We are devastated to hear this might be lymphoma or IBD, and were told the only way of knowing for sure is by doing a biopsy. We have an appt for Monday morning but am really wondering if this is the best decision. Is it really safe for her to go under at her age and condition? Will she be ok while healing and still having chronic vomiting episodes?
This cat is my world and any help or advice would be much appreciated. I don’t want to make any selfish moved here, and want her to be as comfortable and happy as she can.
Thanks,
Vee
Hi Vee. I’m so sorry to hear about your kitty. 🙁 And I completely understand your concerns, I feel exactly the same way with my cats and always try to make decisions based on what’s best for them, not for me (which can be very difficult to do sometimes!) There are lots of factors that go into deciding whether or not to do a biopsy. In your case, it adds a level of complexity when you consider the age of your cat, and the fact that she will need to undergo general anesthesia, which will put her under an additional amount of stress. Although no one can tell you definitively what to do since the decision will ultimately rest with you, I might be able to offer a perspective that may help.
Whenever I’m faced with a decision about whether to biopsy (which I have been, many times), I always ask myself “Will the biopsy results ultimately affect the outcome?” In your case, if the biopsy comes back positive for intestinal lymphoma, will it change your decisions about how to proceed? If you think you would elect to do chemotherapy for your kitty, then you’ll definitely need to know for sure it’s lymphoma you’re dealing with. However, if you don’t think you will elect chemotherapy, then knowing for sure that it’s lymphoma won’t truly affect the outcome.
Chemotherapy and radiation treatment for dogs and cats with cancer is never curative. At best, it can sometimes put the cancer into remission and buy some time (average for dogs and cats, depending on the cancer, is usually 6 to 12 months). The big question is, at what cost? Those factors depend on the type of cancer present (some cancers respond better to treatment than others), the age of the patient, and how deeply their quality of life will be impacted. Those would factor into your decision to pursue chemo. On the other hand, if it is cancer, and you don’t elect to pursue chemotherapy, your choice would be palliative care – to treat with medications (usually steroids) that may or may not temporarily help her symptoms so you can make her as comfortable as possible for the time she has with you.
The other wild card in this scenario is the fact that it could be IBD. So your third option would be to not do the biopsy, immediately begin treating it as if it were IBD, and see how she responds. When you think through it, in my opinion; it stands to reason that the main benefit to performing the biopsy would be if she definitely has intestinal lymphoma, AND you would elect to do chemotherapy. Otherwise, if you rule out chemo as an option, your choices would be to try to treat the IBD and see how she responds, and if she doesn’t, then it would make sense to go straight to palliative care.
I hope this makes sense and is helpful. Whatever you decide to do, I know based on what you wrote that you will make the best decision for your kitty. If you have any additional questions, please don’t hesitate to email me directly through the “Contact” page of my website. I’m wishing you all the best, and my thoughts and prayers for a good outcome are with you both!!
Thank you so much for this advice. I have a male cat, just under 11 years old, who has the exact same symptoms. I scheduled him for surgery for this upcoming Wednesday but have felt torn about putting him through such a physically traumatic experience. Your response to the original commenter supports my decision to move forward with surgery since I will treat him in whatever way best fits the results, including chemotherapy. Your answer was the exactly what I was looking for.
Hi Ann, I’m so glad the article helped you! How did your kitty do with his surgery and biopsy?
Hi. I am so heartbroken over the death of my 6 month old kitten. She came to me on 30 March at 5 months old, healthy eating well, sleeping well. normal little baby. I was besotted with her. One afternoon (Monday 1st May) she suddenly just turned away from her food. When she did this again the next morning I booked her in to see my Vet – as the vet went to take her temperature a little worm came out her butt, Vet said she had a tapeworm, but she had had her vac’s a month prior to coming to me. So we thought perhaps it was the tapeworm that had affected her appetite . I took her back to the vet the next day , they did preliminary blood tests and found nothing wrong. By Saturday I was getting really worried as she still wasn’t eating so I took her to a Vet Hospital, where they scanned her, x-rayed her, and did more bloods tests. Her neutrophils were low, and the vet said from the scans and x-rays she seemed to have an obstruction in her gut. He then gave her an enema. Every day I could see my precious child was more and more unhappy. After the enema another scan, obstruction was still there, so he asked me if he could operate, I was in a terrible emotional state and would have done anything to get her better. After the op that was it – she went so down hill that the vet phoned me the next day and told us they will have to put her to sleep.
They took a biopsy and sent it away. It is now 2 weeks ago and I still have no results, – however this Vet is saying he suspects Panleukopenia. I cannot believe this and am battling to come to terms with his diagnosis. She had no temperature, no vomiting, no diarrhoea, only the loss of appetite.
Somehow I wish I had not approved the op. Am so so heartbroken
Janice, I am so very sorry to hear about the loss of your little girl. It’s always heartbreaking when we lose any of our precious ones, but when they are so young and there’s seemingly nothing we can do to help them it’s just devastating. Please don’t second-guess your decision to approve the surgery – if your kitten truly did have an obstruction, surgery was going to be her best chance at survival. I would have made the same choice if it were my kitten. Do you know what it was that they biopsied? And did she truly have an obstruction?
If she did have panleukopenia, unfortunately her chances of survival were very small since it’s usually fatal in kittens. Sometimes this virus can cause the lymph nodes in the gut to become so enlarged that they may look like an obstruction on x-rays. This could be what happened to your little one, especially if the vet didn’t find any evidence of obstruction in her intestines. But again, please don’t second-guess yourself, because even if it was panleukopenia and the surgery hastened her decline, the outcome (passing away) would have likely been the same either way. It’s just a very tragic situation all the way around.
Please try to remember that in her short life, she was obviously loved VERY much, and you did everything you could to try to help her. She was cared for and protected, and she knew she was loved. I hope you can eventually find some comfort in that. My heart goes out to you. <3
Hi Camille, thank you so much for your reply and kind words. The results came back last week, and thankfully it was not panleukopenia, as my baby came from a Persian rescue center. I still do not fully understand the results, the Vet had a meeting with my husband and I to discuss her case. There was no obstruction but he said her gut and intestines were not functioning properly and the skin of the intestines were very thin. It would seem that she was born with this, and perhaps had the FIV virus even though she did not show up positive on the initial blood tests. Time will heal my broken heart, Many thanks Camille, kind regards Janice.
I am relieved to hear it wasn’t panleukopenia, as that could have meant disaster for many of the kittens at the rescue center where your little girl came from! That being said, it certainly doesn’t help to ease your pain. 🙁 It sounds like your kitten may have been born with a congenital defect that just didn’t allow her to process food normally, in which case unfortunately there was probably very little that could have been done for her, despite everyone’s best efforts. So Janice, please take comfort in the fact that you did everything you could. Despite the outcome, although her life was short, your sweet kitten was truly loved and in the very best place she could have been with you. <3
Hello my dog of seven. Has arthritis in hand legs After he had both cruciets done, when he was two and four years of age,he has lots of lumps hard and sort and is limping on his right leg,vet wanted to sedate Hi and do blood tests and biopsys, but he is a big dog weighing about 65 kg, he is terrified of vets it took enough gas to knock him out which was enough Tp knock out two horses, he is not eating much at all just a little bit of meat or yoke of egg,in eve, im worried he wont wake up from being sedated, After last op we got a call to pick him up as Aftet ten mins of waking he was stressing, i dont want to put him through all 15 to20 biopsys, im trying to keep calm but its breaking my heart of what to do.
Hello, and thank you for writing! First, I just want to clarify that if your dog has a large number of lumps, they will not need to biopsy all of them – they will usually only biopsy one, maybe two if some of the lumps feel different when you touch them. Also, if your dog had a difficult time with stressing after anesthesia during the other surgeries, the vet can always try a different type of anesthesia for the biopsy that may help him not stress as much. I do agree, though, that if you have a large-breed dog who is 7 years old, he would be considered a senior, and thus his risk for anesthesia would increase. So an option would be to just have his blood testing done first and see if that shows anything. If the blood tests are normal and your dog is still not eating and feeling badly, then a biopsy might be warranted.
I hope this helps… please let me know what you decide, and wishing you luck!
Thank you for the wonderfully informative article –
am taking my white cat in for a vet appointment this week, and am anxious, as I’m certain he has skin cancer (squamous cell) on his ear and face. I feel its been misdiagnosed in the past, and he’s been given steroid injections and topical treatments with no improvement.
Wondering if a skin scrape can also determine the presence of cancer cells ?
Concerned that a vet had quoted me last year, when i had inquired about the possibility of it being cancer, of costs ranging from $600 – $1,200 for a biopsy. (So filled with regret for not pursuing the path with another vet though, as this one was so discouraging about the procedure , and skeptical that thats what we were looking at. Am now a year further down the road with a loved cat that has more obvious skin issues now).
Hi Dianne, how did your vet appointment go? Unfortunately skin scrapings are not usually used for suspected skin cancers since they don’t go deep enough into the tissue to get a good sample of cells. $600-$1200 for a skin biopsy seems pretty steep to me, did you end up doing the biopsy? If not, I would definitely get another quote or two, sometimes there can be quite a difference in diagnostic testing costs between veterinarians!
I will be taking my dog for a biopsy on a lump that is in the outside of his rib cage. How should I care for him once I bring him home from the appointment? Are there things I need to look for once we are home?
Hi Jamie, my apologies for the late response, as I’ve been away from the blog for awhile due to having surgery. 🙁 How did your dog do after his biopsy, and how is he feeling now? Did his lump require surgery to completely remove it? Usually biopsy sites only need one or two stitches, so the most important thing is keeping the site protected from the dog licking it…otherwise, recovery time is usually very quick. Again, apologies for the delayed response, and I hope things went well!
My dog has a huge lump on her elbow, and now I can’t take her to an oncologist. There was only one in town, and they are now closed due to coronavirus. First, does she really need a biopsy – I’ve been told we do need to find out if it is cancerous, because if it is benign, it will make the surgery easier. There are concerns about her having enough skin left. So I think we just need to find whether or not it is cancerous, not necessarily what kind or what stage it is. I would not want to put my dog through chemo anyway. Second, I have a dumb question about the skin issue: Couldn’t the surgeon cut out the tumor, but leave enough skin to cover the wound? A week ago I would have thought all the skin needs to go too, but she is on pain and anti-inflammation meds that have helped tremendously. The skin is no no longer dark red. So that is my 2nd question: Why would all the skin have to be removed too? We are going to take her to yet another veterinarian, known to be a good surgeon, but he’s not a specialist.
Hello: Your website is very informative and am glad I came across it. I have a 14 yr old male cat who has what my vet says looks like squamous cell carcinoma on the nasal planum (nose pad). He is also hyperthyroid and has been on medicine for that. My vet scheduled a biopsy ($930.00); however, I have decided that Stitch not have the biopsy. His nose has gotten bad within the past month, the poor guy knocks off a scab every now and then which breaks my heart because I know it must hurt bad. A few weeks prior to this last appointment our vet had given me Entederm ointment (antibiotic, anti-inflamatory, anti-fungal) and I use on his nose it twice per day (and also if he knocks a scab off as I want to get the medicine on the open area). At this last appointment the vet gave me pain medication to use at the times Stitch appears to have pain. I have been praying on this and my blessing of a neighbor came to talk to me about it. She had worked in a cancer center/ward, and explained squamous cell carcinoma (this horrible plague has also made it so can’t meet with the vet face-to-face…bless their hearts, they are very swamped with clients). My neighbor told me that it is malignant. To make a long story short, she knows Stitch (as do most people in the neighborhood) and said he would be so stressed to have the “punch” biopsy, she knows the funds are tight to spend when I already know what the outcome is (and the vet had already said what it looks like), and that I may want to consider just letting him continue to have the quality of life, to enjoy him, to let him live life the way he’s used to, without the stress, to manage the pain….and that the Lord will guide me and give me strength when it’s time to make “the decision” out of love. I had already decided against any chemo or surgery. Reading over what I’ve written (sorry for the length), I know it’s the right decision. I just wanted to share, thank you and God bless.
Hi,
I’m hoping you can ease my troubled mind. I adopted a cat last year, the original post on him said he was young. After I adopted him, I received his medical records, it looked to me like the doctor put seven years old on it. Still, no problem I love him, it took me three weeks of working with him, but he’s now a lap cat.
He recently had begun sneezing and getting a nose bleeds after sneezing. I made an appointment with my vet. He needs some teeth extraction, but the nose bleed is a separate issue. Worse case scenario is it’s a tumor in the nasal passage, which I won’t know if I don’t allow them to do a biopsy. The biopsy is with the teeth extraction is well over $2500. This causes a financial hardship on me, but I want to know. CreditCare or CareCredit only gave me $1450.00, I’m sorry my heart hurts, so I can’t recall the right name. He’s part of my family, not just a pet.
The vet didn’t do an X-ray, my question is, how can they tell it’s cancer if they didn’t do an X-ray? Of course she told me it could be rhinitis, but she sounds like she’s leaning more towards cancer.
I recently found out that this cat was never an indoor cat, he was feral and I was never told this, but he’s good in the house. Please, is tell me if my Rocky, could possibly not have cancer? Thank you for any help you can give me.
Teri
Hello! My 14 year old terrier mix has a lump on his back leg. Cytology is suggestive of malignancy so my vet wants to do a punch biopsy. He is going in tomorrow for that as well as a chest X-ray. Since he will be under general anesthesia, is it wise to have his teeth cleaned as well? They are pretty bad, he may need extractions, and if he is already “under,” this would limit going under at a later date. But … is it even appropriate if, as it seems so far, he may have cancer, and we should focus on his leg and other parts, rather than his teeth? He is walking fine and appears otherwise healthy. Also, my understanding is that if this is cancer but there’s no metastases, that the most likely treatment would be amputation. If if it has spread, he would most likely have chemo or radiation. My feeling is, at age 14, he could probably live out his life, without going through all those treatments, and if/when things get bad, we would have him put down. I know dogs adapt pretty well to three legs but he’s older and why put him through that (or chemo/radiation) at this point in his life? I’m heartbroken that things have turned out this way but I am being realistic and don’t want him to suffer. Thank you for your time.
Hello my dog is 13 years old she has oral tumor and it shape is bigger. Does biopsy Is give by sedatives or anesthasia. Which treatment will help her chemo or homeopathy?
My Samoyed has lost pigmentation around her mouth and nose. My vet believes she may have uveodermatologic disease and sent me to a canine opthalmologist who examined her and would like to perform a biopsy to diagnose. The biopsy cost is prohibitive (1,500-2,000). Is there another option?