Hello everyone. My name is Catherine Puesenberry. I'm the chief medical officer at the the Schwartzman Animal Medical centre in New York.

I'm also the head of the Avin and Exotic Pet Service in New York City. I'm gonna talk to you today about neoplasian birds, common presentations, and treatment options. So, the objectives for the lecture today are 31 is to describe the general approach to the diagnosis of cancer in birds.

The second is to give you an overview of current treatment options. And the third is to describe common types of cancer in pet birds with examples from the literature and clinical cases. So cancer is common in pet birds.

Why is that? I think for one, we are seeing more older pet birds. Many of the birds, at least in the US were imported.

The large citizens were imported in the 80s, the 70s, the 80s, and the early 90s, and then with the passage of the wild bird Conservation Act, these were no longer imported. However, many of these birds are now in their 40s, 50s, so we are seeing older bird population. Two is owners do seek out advanced veterinary care.

They, these birds have been in their household for many, many years. They want to provide the best possible care for these birds, so they are seeking out more advanced options. More veterinarians are willing to treat birds with cancer.

Back when I started, there were very few veterinarians who would treat birds in general, but now many veterinarians are, have expertise in avian medicine and also partnering with, with, with oncologists, small animal oncologists who are willing to, to work with avian veterinarians and work out treatment options. And also, we do have more treatment options. There have been a lot of case reports in the last 20 years or so of, of different types of cancer and pet birds and what, what treatments are given.

What are the risk factors for cancer in pet birds? And I'm gonna refer you to a really excellent chapter in Spears Advances in Avian medicine, and this is by Ashley Zinder, and it's a really great chapter for an overview of cancer and birds. But to talk about the risk factors, basically, we don't know what the risk factors for cancer.

I mean, we talk about ageing, but there are other things. One is the diet. There's been some theoretical literature about the, the hypovitaminosis A in birds.

And how that may predispose to things like squamous cell carcinoma, but we don't know. Another one is viral disease. We do know that there are some viruses that cause cancer in birds, particularly in galiforms and answer forms in chickens, ducks.

These are viruses such as herpes virus which causes Merck's disease in chickens. We have retroviruses such as the rosarcoma virus. The lymphoid leucosis virus and the reticular endotheliosis virus.

So these are known viral causes and siting birds, there are some associations, for instance, between cetaid herpes virus. And cloacal papillomas in in Amazon parrots, but again, it's not been proved. Chronic egg laying in some of these small birds, which we'll talk about later, these birds lay eggs prolifer, proliferatively year-round, so this may cause changes in the ovary that predisposes them to cancer.

And then finally chronic inflammation and wounds. Any sort of chronic changes to the epithelial surface can predispose the cells to transform and become dysplastic. How do we stage cancer in birds?

Well, there's really no staging system that is validated in birds. We do somewhat follow the WHO clinical staging system. We certainly talk about the anatomic site of the cancer.

We do try to stage it and, and perhaps also substage it if with or without clinical signs and birds. In mammals, there is a system called the TNM system, and I'm sure you're aware of this. T is to describe the tumour, the size and extent of the main tumour.

N is the number of regional lymph nodes with cancer, and M is whether or not there's metastatic disease in other parts of the body. Birds lack lymph nodes. So basically, we are using the TM system description of the tumour and description of any type of metastatic disease.

So, we start with, of course, the lesion. There's a lesion on a bird. This may be noticed by the owner.

It may be noticed by the veterinarian on a physical exam. So we talk about where's the lesion, how long the lesion has been there? Has it grown slowly?

Has it grown rapidly? And are there any signs associated with that lesion? We wanna get a good history.

We wanna know what the age of the bird is, of course, the species of the bird, dietary history on the bird, any previous medical history related to the mass. Then of course, we do our initial physical exam, and this should usually include a complete blood count and a serum biochemical analysis. You want to look for signs that could be associated with the tumours such as if the bone marrow is involved, the bird could be anaemic or it could be leukopenic.

Or there may be leukocytosis, maybe there's a concurrent infection. And also just to assess the general health, if there's involvement of the liver, if the liver enzymes are up, if the uric acid is elevated, to give you an idea of what's going on with the bird in general before you go further. And then we want to assess the primary tumour.

You want to get if you some preliminary measurements, baseline measurements, if it is a measurable tumour, and we'll talk a little bit more about that. You wanna get your initial imaging. This could be radiographs, it could be a CT or it could be an ultrasound.

And of course, you want to do some sort of histologic examination or cytologic examination to try to determine what type of tumour it is. And then you want to assess for metastatic disease and that usually goes back again to some type of imaging, usually a CT ultrasound, something like that to see if there's evidence that the tumour has spread. If it has spread, you may want, or if there's suggestion that it has spread, you may want to also biopsy those secondary lesions or do cytology.

What are our treatment options for cancer in birds? Basically, Surgery is always going to be the best option. If you can cut it out, you should cut it out.

Where we come up against issues and problems and challenges in birds are getting margins. Many times these in birds, if the tumour is on a skin. Or, or some other body parts.

We cannot get the margins, for instance, that you would get on a skin tumour in a dog or a cat. The birds just don't have that loose skin that you can get a 2 centimetre margin. So we're dealing with that.

Also, many of these tumours are non-resectable, so we can't use that, but if you can cut it out, you should cut it out. Radiation therapy is a second option that can be either external beam radiation therapy or plesiotherapy, which is really strontium 90 probe, which I'm gonna talk about. And then, of course, there's chemotherapy, and there are many case reports in the literature and we'll talk about that in as we go forward.

So I wanna talk a little bit about assessing response to therapy. You want to first determine is this a measurable, measurable versus a non-measurable tumour. For instance, if you have a tumour such as in this photograph, you can measure it, and I'm gonna talk a little bit about how to do that, but this is where I think We as avian veterinarians are probably not as adept at this as our small animal counterparts unless you have good training in oncology.

I know this is one of my downfalls here on how to assess this tumour. How often are you gonna assess it? Are you gonna assess it monthly?

Are you gonna assess it every two weeks? It also depends on the treatment that you're using and how often the bird is coming in for treatment. So that should be established.

You also need to evaluate non-target lesions, and that could be ascites, it could be changes in haematology or biochemistry to see what else is going on with the bird and see if those aspects of the examination are improving or not. And then, Then you have to assess the response. So there is data, there's there's a programme called Resist, which you may have heard of.

So Resist is basically the response evaluation criteria in solid tumours, and basically they have categorised four different types of responses. There's a complete response, the tumour is gone. It doesn't come back, 100% cured.

Then there's partial response and partial response, according to resist guidelines is, is, is defined as a 30% decrease in the sum of length diameters from the baseline, which basically means if there's more than one tumour, there's a 30% decrease in the sum of the longest length of all those tumours, which I, again, we'll talk about on the next slide. Then you have stable disease, which means there's no partial response, but there's no progression of disease. And then you have progressive disease which is a greater than 20% increase in the sum of length diameters compared with the smallest or baseline sum of length diameters, or there's worsening of the non-target lesions or there's new lesions.

So for measurable lesions, We have, I think in veterinary medicine traditionally called tumours by their size. I know when I start and for the most part, I'll say it's a grape size tumour. It's a, a pea-sized tumour.

So that's kind of the language we're used to talking about and that is kind of a circumferential diameter of the lesion. But if you want to be more accurate, you really should use callipers and you want to measure the tumour in the longest diameter. So if, if the tumour is 3 centimetres long and 2 centimetres wide, you wanna surely measure that longest diameter, the 3 centimetres, and use that as your baseline.

And really the same person should measure the tumour over and over. When you have different people measuring it, they may use different techniques. So that can cause some confusion in, in assessing response.

If you are measuring it radiographically or by diagnostic imaging, CT is really preferred over radiographs, and ultrasound, it's a much more accurate measure. And again, you want to measure at baseline. If there is more than one tumour, you are looking at the sum of length diameters.

Now, switching to talk a little bit more about treatment. So there's external beam radiation therapy. There's really very few studies in birds using external beam radiation therapy.

Most of the information that we have comes from individual case reports of varied cancer presentations in birds. The thing that we do not know is the long-term effects of radiation therapy in birds. Many of these case reports, the birds were only followed for maybe a year or two, and we don't have really the follow-up information about this.

One study from 2009 looked at Indian ringneck parakeets, where they gave these birds a dose of 4 grey fractions over 3 times a week over a period of time to a total dose of it is 72 grey. And what they found when they looked at the epithelium, there was really very little change in the epithelial tissues, so their, their, their conclusion was that the radiation doses of 72 grey and 4 grey fractions were really well tolerated in these parakeets in this dose study. There was also a study in McCaws that was done in 2016, where they took three adult macaws, and they looked at the comparison of calculated versus the actual radiation delivery in macaws.

And they placed a dosimetry chip in the kanal of these birds, and they, they calculated the radiation dose to reach this dosimettry chip, and they measured that to the actual dose measured in the chip, and they found that there was a 10% dose in homogeneity between the calculated dose and the delivered dose. The the conclusion was that in the skull of birds, the anatomy, the unique anatomy with these, the sinuses filled with air and birds may affect the radiation delivery in birds. So that is something to remember if you're thinking about radiating the skull of birds.

Strontium 90 is Slightly, well, it is very different as far as delivery of radiation. This involves a radioactive source at the end of a rod, and this source emits a very low energy beta radiation. However, it does deliver a large single dose of radiation.

The downside of this is it only penetrates 2 to 3 millimetres. So you have to have lesions that are very shallow. You can't use this in deep lesions, so you really have to pick your cases when you want to use strontium nondi probe.

Debulking is often necessary before treatment, depending on the case, and we'll show you, I'll show you some case examples of that. Chemotherapy and birds, basically, there are many drugs that are used in small animal medicine, and these drugs have been extrapolated when the dosages are extrapolated from the use in humans and mammals because we really don't have a lot of study in birds. There are the alkylating agents such as chlorambuil and cyclophosphamide.

These are used primarily for lymphoma, leukaemia. They also used for sarcomas. These have been described in many case reports in birds.

There are anti-tumor antibiotics such as doxorubicin, and these are also used for lymphoma and leukaemia and also for epithelial tumours. Not quite as many descriptions of use in birds. Then rising has been used in birds.

This is a vinca alkaloid. This is also used primarily for lymphoma and leukaemia. There's the platinum products.

These are used more commonly for sarcomas and carcinomas, cisplatinum and carboplatinum. There's Esparinase, which is an enzyme that's used for many cases of lymphoma, and there's also the nitrosuras that are also used in lymphoma such as lomustine. Now there are dosage as you, if you have carpenter's formulary, his, the last edition and also the newest edition provides dosages for use in birds, so there are dosage dosages there.

What are the challenges of chemotherapy and VERD? Well, there's the main challenge that we have is the limited vascular access for any sort of IV administration. If you're going to get an IV drug, You most often have to anaesthetize the bird for this administration.

You have to pick your vein, whether it's the jugular vein here or if it's a larger bird, perhaps the metatarsal vein or the wing vein, so it becomes quite challenging. There are also few pharmacokinetic studies in birds using these drugs, and that's why we pretty much extrapolate from human and small mammal doses. Birds have a very high metabolic rate compared with mammals, so probably the half-life for many of these drugs is much smaller.

In, in birds. There are some drugs that are based on allometric scaling. Many of these drugs are based on allometric scaling in mammals.

There's not a lot of information whether or not allometric scaling works in birds better than milligramme per kilogramme. We also have to look at the renal portal system in birds. So many drugs are excreted through the kidneys.

So in those With those drugs, you certainly would not want to use the metatarsal vein to use a drug such as this. And then with corticosteroids, which are used commonly in mammals, there is a risk, a great risk of the immunosuppression in birds with the use of corticosteroids. There's limited chemotherapy research in birds.

There are several studies done by Doctor Philippi in Australia in the early 2000s. He looked at cisplatinum and sulphur crested cockatoos. Basically, he found that this drug had too many adverse effects.

He lost one or two birds in this study from this drug. So then he used carboplatinum, and he found this was well tolerated in these birds, and he found a half-life of about an hour at this dose of 5 mg per kg. He, there was also a study on doxorubicin and sulphur crested cockatoos, and that drug at this dose of 2 migs per kg, they found a half-life of about 41 minutes.

This is a more recent study that looked basically at the half-life of carboplatin and 1234 different species. They looked at chickens, ducks, pigeons, and parakeets. And what they found was there was a very strong correlation between the body weight in birds and the half-life.

The higher the body weight, the longer the Half-life. So this gives some evidence that probably using a milligramme per kilogramme basis would work if you're trying to figure out dosages, but we just don't know. There are formulas for calculating the body surface area in birds, and you can look it up online.

I think Carpenter also has that in his formulary, so you can, calculate that. Then lately, of course, there's more information in small animal medicine on the use of targeted molecular therapies such as P Palaia, which is a tyrosine kinase inhibitor, and this was first developed for mast cell tumours in dogs. It targets the vascular endothelial growth receptor and other receptors such as the platelet derived growth factor.

In dogs, it can have fairly severe GI adverse effects. I could only find one report in a bird, and this was a recent publication in 2020 where they use this drug in a black-headed chai at a dose of 10 mg per kg once daily. They did have to discontinue this drug at 2 months because the bird.

Suffered from fairly severe hypoalbuminemia and also it was not, helping the tumour. The tumour did progress. It was in a squamous cell carcinoma.

So we don't have a lot of information about using palladium and birds. Mesininib is another drug. This again was originally used for non-resectable mast cell tumours in dogs.

I don't have information of that. It's not approved for use in the United States. OK, we're gonna switch to talk about common types of cancer in birds.

So I'm gonna try to highlight the cancers that I have seen most commonly in birds in my career. There's certainly gonna be cancers that I'm not gonna talk about, but, but we'll try to hit the describe some of the more common ones. The Euridal gland birds is Really, present in most birds.

It is absent or at least vestigial in some Citocene species such as Amazon, Paris and hyacinthmacas, also in doves and some pigeons. And this gland varies in shape among species. It has anywhere from 1 to 5 openings with a little tufted feather tuft at the end, which is sort of used as a brush to spread the oils.

It's a holon gland, the cells break down. The fat in the cells breaks down into fatty acids, and this then is converted into wax and it functions in vitamin D, synthesis and waterproofing in birds. So, it's essential in maintaining normal skin.

So if you have a bird with a problem with the epigeal gland, they probably are also gonna have some skin and feather issues that you're gonna see. This is a very common side of neoplasia in some species, and you can see anything from adenomas, adenocarcinomas to squamous cell carcinomas. Typically, I've seen it more commonly in young, not young, but in small birds, parakeets, cockatiels, and it typically presents as either a scab-like lesion at the base of the tail or a fairly progressive lesion such as in this larger picture.

The owners usually notice it and then bring the birds in for this. Treatment of your pigeal gland tumours, various things have been tried. Surgical debulking of this area is very difficult just because it is very tightly adhered to the bone and the skin and it's also a broad-based gland.

So that's very difficult to remove that gland in entirety. It's also very difficult to know if you've got margins on that. There have been reports of tail amputation in birds, for treatment of epigeal gland tumour.

There was one report in a macaw. The macaw seemed to do well after the surgery, but unfortunately, it died 3 months later of an unknown cause. So we don't know.

We don't know if that's the way to go. Cryotherapy, such as in this picture has been used with variable results. And then strontium 90 plesiotherapy has been described, and this, in my experience has been the most successful.

So when you're using the strontium 90 plesiotherapy, these birds have to be under full anaesthesia. Each application takes a, a dedicated amount of time. In other words, they place the probe on the tumour and then they have to put the probe over all the, the areas of the tumour and overlapping circles.

So if you have a larger tumour, this can take quite a quite a while. It can take 30 minutes, it can take 60 minutes depending on the size of the lesion that you're trying to treat. And repeat treatment is usually necessary.

There are some reports where a single dose treatment was successful, but in my hands, in my experience, usually you need at least a second treatment. You would not want to use it on a bird such as in this photo, this lesion is way too extensive. Again, when we're talking about strontium 90, you have to debulk the lesion because it only penetrates 2 to 3 millimetres.

These birds, a scab usually forms after treatment. So you can see in this little bird after treatment, there's a little scab there and then that will fall off and usually the birds do well. Switching over to talk about lymphoma and leukaemia.

So lymphoma is probably one of the most reported lymphoid. Tumours in birds in parrots. We don't know the overall incidence in in a study of birds, zoo birds, lymphomas made up about 33% of 39 tumours, so it is quite common.

Usually in parrots, we see a multicentric form, but it can occur as a localised form, and I'll show you some examples of that. Again, as I mentioned earlier, there are some viral causes associated with lymphoma in chickens and in answer forms, particularly the herpes virus for Merrick's disease, and then various retroviruses such as the avian leukosis virus and the repticuloendotheliosis virus in chickens. When it is multicentric, it, it primarily can, it can start in the liver and the spleen, but it can really appear in almost any organ.

It has been described in just about every body system, including the bone marrow, the CNS, the eye, the GI tract, the heart, the skeletal muscle, the skin, and the thymus and the bursa. Generally, these do arise from lymphoid tissues in these lymphoid rich organs such as the spleen, the thymus, the bone marrow, and the bursa in birds. They can be B or T cells, and as I said, they can invade any tissues.

And again, in sitize birds, there's no causal evidence of a virus. Clinically, the onset can be anywhere from 5 months to 30 years. The clinical signs are variable.

It can be weight loss, paresis, lameness, abdominal swelling, feather loss, diarrhoea, and dyspnea. On a CBC. See, you can see anaemia if the bone marrow is involved.

You could see leukocytosis with lymphocytosis. You may also see lymphopenia. You could see monocytosis, you know, see eosinophilia and heterophilia, particularly if there's a secondary infection.

Your biochemical changes can reflect the organs that involved, such as the liver, the kidneys, the with changes in those values, and on a protein electrophesis, you may see changes in alpha beta globulins which would reflect the acute phase proteins. So, you can, and you should take biopsy samples and you can submit this for immunohistochemistry. These can either be B cell.

This is a, a lymphoma in an African grey parrot, and this was the bursa, of course, which you would expect to be a B cell lymphoma. However, various stains, in, in immunochemistry have not been validated in birds. So there are various B cell stains.

They are used, but again, they have not been validated. For T cell stains, the CD3 stain, this is a protein receptor on T cells, and this has been shown to be accurate for T cells in chickens. So these stains are used in birds.

This was a study or, or a paper. That was published in 2008 where they used a micropositron emission tomography or a micro PET scan of the birds, so they gave it radioactive substance IV and then they did this PET scan. And through this, they could show that there were I see if I can get my pointer here, there were lesions here in the intestinal tract that showed that this, this lymphoma was throughout the intestinal tract.

This was biopsy samples from this. You can see in the villa of the intestine, it's very diffusely infiltrated with lymphocytes here, and here they did do a CD3 stain and they found that these were very positive and you can see here for the CD3 stain which indicates this was a T cell lymphoma. This is a case report of a description of a non-epitheliotrophic B cell lymphoma in a cockatoo.

This bird presented with disseminated subcutaneous nodules anywhere from 3 to 2 centimetres in diameter. They had it had longitudinal yellow plaques in its skin and also enlarged feather follicles. This bird had a leukocytosis of about 75,000 with a lymphocytosis.

And in this stain, you can see it was an immunohistochemical stain where they use BLA 36 and these cells strongly identified as B cells. So this was a B cell lymphoma in this bird. They treated this bird with different types of of therapy.

They used vancristine. And they gave this IV. They also use chlorambucile orally.

This bird at week 17 was very depressed. It became very anaemic, so they stopped the chemotherapy. They did follow this bird for about 8 years, and they found it was in complete remission, but it did have a consistent lymphocytosis.

This was a bird that we saw as a sort of a, it was an adult, not too old African grey parrot that presented with a swelling on its left eye. This is the CT scan from this bird and you can see there is soft tissue swelling behind the eye, retro bulbar area and also in front of the eye in this bird. So this bird we did treat, we put it on a treatment of chemotherapy using cytoxan, and we administered this subcutaneously every 2 weeks or so for about 6 months, and this is about halfway through the treatment and you can see it's still a little bit prominent compared to the other eye, but This was at the end of the treatment and the bird looked completely normal.

And this bird, to my knowledge, has stayed in remission since we have seen it. This bird had no evidence of cancer anywhere else in its body. So this bird did quite well just with chemotherapy.

This was another bird that we had seen. The bird was a 1 year old Indian ring neck, and it presented with a two-week history, so it was a young bird, presented with a two-week history of lameness. It had also had diarrhoea and recently blood was noted in the droppings.

The referral vet had done blood work and the bird had a 7000 white cell count, but 95% of the cells were lymphocytes. So we did an ultrasound on this bird and found that it had a very large dorsal mass in the area of the kidney. The mass was very vascular.

So, the owner, knowing that this was likely a non-resectable neoplastic lesion, decided to euthanize the bird, and we did find lymphosarcoma in this bird in the kidneys, in the liver. Really, we found it everywhere. It was in the sciatic nerve, in the brain, in the small intestines, in the bone marrow, even in the syrinx of this bird.

So it was a very diffusely multicentric lymphoma in this young bird. Leukaemia is rare in ying birds. It originates in the bone marrow.

It can be chronic. You can see chronic lymphocytic leukaemia, which is usually a T cell origin. B cell origin is more where you associate the more the lymphoblastic leukaemia.

There is a report of chronic lymphosemic leukaemia in a green wing macaw. This bird was clinically normal, but it did have progressive lymphocytosis with a monomorphic population of lymphocytes in the bone marrow, and these lymphocytes stayed positive for CD3. They were negative for BLA 36, so this appeared to be a T cell, leukaemia.

So this is the bone marrow on this bird and you can see packed with, with lymphocytes here. And again, here is the CD3 stain and these cells are very positive for the CD3 and the BLA 36 stain, there's very few cells that are staining positive, the ones that are or more of the monocytes. This bird was treated with different drugs.

It was started on chlorambucil twice a week and also prednisone, but the bird did not respond to the chlorambuil. They had an increased white cell count. So basically, they stopped it and then they started cyclophosphamide when the birds started, the white cell count started to go back up and then, and they kept it on cyclophosphamide for About 25 to 30 weeks, but then they had to stop it and the due to situation beyond their control, this was Hurricane Katrina and the bird, the white cell count increased again.

They started the cyclophosphamide, but, the bird did not do well and they ultimately had to euthanize the bird. OK, I'm gonna talk a little bit about squamous cell carcinoma. So squamous cell carcinoma is probably another very common tumour that we see in birds.

It can develop anywhere on an epithelial surface, the face, the beak, the skin, the oral cavity, the epigeal gland. It initially presents as a non-healing proliferative lesion. You may not think that it, you may think it's a fungal infection or just a, a non-healing lesion for whatever reason.

Treatment options, many have been described such as surgical resection, cryotherapy, using the strontium 90 probe that I talked about, also radiation. There was, this is an example of a case report of trying to treat squamous cell carcinoma and flamingo with radiation where they used 310 grey fractions of radiation on a 3-day palliative treatment course, 30 grey total, the bird did not respond. They gave it additional radiation, and again, the bird did not respond.

They didn't want to amputate the toe cause that would, they would have thought that it would affect the ambulation in this bird, but they ended up amputating the toe and it was curative. So, again, it shows you if you can cut it out, you should do that. There was also a description of squamous cell carcinoma and African grey parrot on a beak, and they did do external beam radiation.

They claimed in the report that there was no tumour regrowth at the, but the bird died 4 months after they stopped treatment. So again, we don't know. This is a case that I actually had, and you can see this bird had a very, very severe lesion, squamous cell carcinoma.

We did try radiation on this bird. Again, very, very poor response and we ultimately euthanize the bird. There was a really good study by Doctor Zender that was published in JAMA in 2018 where she looked at birds with squamous cell carcinoma and the treatment and she found that only a very small percentage of 64 birds had a complete remission, only 6 or 7 birds out of those.

83% of those birds had progressive disease, so it's not a great tumour to have. Birds that were treated with surgical excision were 7 times more likely to have either a complete or partial remission compared with any other treatments. And complete excision was the only treatment associated with increased survival time.

This is a bird that we had that we tried to treat with cryotherapy, but again, did not work well on this bird. You can see here we froze this and I think we tried this on this bird several times in a row, but it did not stop this. This was another little cockatiel that had squamous cell carcinoma on the potagium.

This bird actually did quite well with Strontium 90 probe, and you can see here this was after treatment. It only had a very small scab here and this went on to heal fine. And this bird did well.

So, certainly, surgical excision, if you can, if you can't, then surgical debulking with something like strontium 90 is probably the better way to go. Sarcomas, I'm gonna talk about several types of sarcomas. You have, sarcomas are spindle cell malignancies of mesenchymal cell origin and really it's classified according to its origin, of course, we have bone, osteosarcoma, fibrosarcoma, cartilage, which is carosarcoma, smooth muscle, liomyosarcoma, skeletal muscle, the rhabdomyosarcoma, blood vessels, hemangiosarcomas.

All of these have been described in birds. Osteosarcomas or fibrosarcomas usually occur on the wing or the leg. It can occur in all ages and in all species.

It's commonly seen in cockatiels and parakeets. These birds, if you can, you want to just amputate. Non-surgical treatment for these types of tumours.

Basically, you're looking at something like radiation therapy alone or mixed radiation therapy and chemotherapy, and there are several descriptions in the literature of using these different types of treatment modalities. These are only two. Here was a radiation therapy used for a budgie with hemangiosarcoma on the wing.

Another one using radiation therapy and intratumoral cisplatinum, in this bird and, So you can, you can see various descriptions of different treatment options if the tumour is non-resectable. This was a bird that I saw that presented with a swelling below its mandible on the side of its neck, and of course, trying to understand if we could use some sort of treatment option in this bird. But again, here's where your, your diagnostic image.

Becomes very important. When we did the diagnostic imaging, we could see that there was infiltration of the tumour around the mandible. So we knew that certainly surgical resection was not gonna work and likely even radiation therapy would not work just because of the head and other structures involved.

So unfortunately, this owner had to euthanize the bird. This was a bird that we saw in the last two years. This was a blue and gold female macaw.

She was about 35 or 40 years old, and the owner had noticed this mass sort of on the lateral side at the base of the tail, and it was a slow growing mass. We did do CT in here and we did CT not only to look at the tumour itself, but also to make sure there's no evidence of metastatic disease and you can't see the lungs in this, but on this slice, but the lungs were clear on this bird. But what you can see here how this helped us is that we could see that there was a clear delineation of this tumour, so That gave us hope that we could sort of peel this off of the, of the, the soft tissues here and remove this tumour.

And that's what we did. We took it to surgery. We were able to peel off this tumour, and this is post-op, how it's healing up very nicely.

And on soft tissue, and the, the image on the right was the fine needle aspirate where you can see the, the tumour cells there, chondrosarcoma, and then on biopsy it was diagnosed as a very highly malignant. Chondrosarcoma. the margins were very, very, very narrow, so because of that, We decided to go ahead and proceed with radiation therapy, which we did.

This bird underwent 6 fractions of 6th grade radiation once a week, and this bird has been in complete remission for about 2 years. Reproductive tumours such as ovarian tumours, ductal tumours, and testicular tumours are well described again, usually in smaller species such as the budgeriars and the cockatiels and lovebirds. Ovarian tumours are cockatiels in these small species.

Occasionally we see them in other species, but usually in these heavy egg laying birds. These birds present with abdominal swelling, effusion, weight loss, and dyspnea. And of course, these are generally a poor prognosis.

So what you're probably doing in these cases is just pretty much diagnosing the birds to give the owners an answer as to what's going on. On histology, they can be adenomas, they can be adenocarcinomas, they can be granulosa cell tumours, gliomyosarcomas, fibroid tumours, all of these have been described. Other tumours of the salamic cavities, these are usually carcinomas or adenocarcinomas in these cases.

Of course, renal adenocarcinoma in in budgry gars is well known. It's probably the first tumour you learn of when you're learning about avian medicine, and these little budgies typically. Present with one leg paralysis or paresis with knuckling of the toes, and this is due to the, the pressure on the sciatic nerve in these with these birds with the renal tumours.

But other tumours have been described, hepatic tumours, pancreatic tumours, proventricular tumours. Hepatic tumours, birds can present with just abdominal swelling, such as in this budgie, a very, very prominent abdominal mass you can see here, so you can almost tell just from the physical exam that this is a tumour. On the right is a CT scan of an Amazon parrot that present with abdominal swelling, and we did do the CT and you can see a very complex liver mass in this bird.

So this bird had a very complex limber tumour and it was euthanized. There are several reports of carcinomas of the pancreas in birds, the cause, also in a cockatiel here, and this is a case that we published in an eclectic parrot where we did, just a standing DV box shot and we can see here that there was definitely some increased soft tissue opacity like the a fusion in this bird. We went ahead and did a CT scan in this bird.

And you can see here this mass in this bird that was diagnosed as a pancreatic adenocarcinoma. There was also mets in the lungs, which you can see here. Again, pointing out the, the importance of advanced diagnostic imaging.

Proventricular, ventricular adenocarcinomas are common or uncommon, I'm sorry, but we tend to see them more in older citizen birds, particularly in Amazon parrots, and these birds can present with clinical signs of regurgitation and weight loss. And again, you may pick this up on a radiograph, but if you can do a CT scan such as in this bird, you can see the swelling or the or the increase in the diameter of the soft tissue lining in the proventriculus. Tumours of the respiratory system, many different types of tumours have been described.

The one that we probably see most commonly are these air sacs, cysteinnocarcinomas, in particularly in salmon crested or in cockatoos, which is what I've seen them mostly in, but they have been described in other species, such as the tenna grey and cockatiels. And this is from the case report in the timna grey where this bird radiographically you can see the soft tissue swelling here and this was associated with the air sac and was an adenocarcinoma. This bird also had a very enlarged spleen, which you can see here.

This is a normal CT of a bird looking with the lung view and we can see the nice the, the lung pattern here with the bronchus, . And also you can see the lining of the air sacs here. So this would be a normal lung pattern in a bird and then contrast that with, for example, this bird, this was another case report that we did in a scarlet macaw, and this is one of the first descriptions of using a standing CT in a bird, and this bird presented with increasing respiratory noise.

The bird was extremely dismic when it handled, so we knew. That we could not do a sedated CT. We were really worried about this bird.

So we did a standing CT in this bird and we were able to get a diagnosis of this very, very complex mass that involves the lung lobe here and also that takes up the whole sternal area and you can see the bony involvement here. This bird ultimately was euthanized. And it had a respiratory, primary respiratory adenocarcinoma that originated from the air sac epithelium.

And it did have meds as well, intrasalamic metastasis. Lipoma, I'm gonna talk about quickly because these are technically not, you know, certainly not invasive type tumours, but they can become a problem typically associated with obesity, we see it in the ventral abdomen, in the sternum, and typically in the pericloacal areas, usually not associated with the clinical signs unless the bird itself is traumatising it. This is an example in a little cockatiel here.

Whenever you have a lipoma such as this in the abdominal area, you really need to do some sort of contrast imaging or ultrasound to, or CT to see if there is involvement of the intestinal tract cause a lot of times have herniation of the intestinal tract in this, so you don't want to just go in and cut them off. So again, this is in a galah. You can see this .

Large lipoma here. Another one in an Amazon parrot multilobuated around the cloaca. So these can be quite challenging treatment options are certainly diet modifications, surgical removal as needed.

And if it's abdominal, as I said, you wanna do some imaging to determine if there's a herniated bowel loop. Usually, when you take these, remove these surgically, these are very, very vascular, so just be prepared for that and certainly have your hemostasis ready when you're Removing these. Xanthomas are not lipomas.

They're sort of an offshoot and I just want to quickly mention those. These are non-neoplastic. They're a deposition of cholesterol and foam cells and inflammatory cells commonly occurring in the wings and the ventral abdomen, so they have this yellowish appearance.

Thymomas we do occasionally see in birds. These are tumours that are derived from the epithelial components of the thymus. They contain variable degrees of non-neoplastic lymphocytes.

In humans, they're about 75, 65% encapsulated and non-invasive. There are several reports in birds. So usually these are adult birds, they can see develop anywhere from the base of the mandible to the thoracic inlet.

They are these birds are presented with a space occupying mass with subsequent signs of either dysphagia, crop stasis, or dysmia do compression of the trachea. So this was a CT scan of the bird I showed you the picture of, and the reason we do these CT scans is to look at the involvement of the vascular. So here you can see the jugular vein very, very closely associated with this mass here and you can see how large this mass is.

So you can judge by this whether or not this is something that you can resect or not. . This is another bird with a thymoma and again, you can see it's more cystic, but again, here you can see the jugular vein very, very closely associated with that.

So you have to be very, very careful if you're gonna remove this. This is this little Indian ring neck undergoing a CT scan and a setup to try to to make sure that the positioning would be correct for subsequent radiation. And thymomas are very difficult to treat.

Surgical resection is very difficult because of the intimacy with the jugular vein. And people, radiation is used, chemotherapy is used, if it's lymphocyte rich, and also corticosteroids which we cannot use in birds. This little bird we did use radiation with and initially it was very successful.

You can see the size of the tumour here, it did shrink down, but unfortunately, it did recur after about 2 months after we finished radiation and the bird had to be euthanized. Melanomas are reported in several avian species. They are considered rare.

Generally, they are very low sensitivity to radiation, so you do want to try to resect them. Again, histopath, a diagnosis of melanoma in a cocker tube. There are descriptions of treating melanoma with either radiation and or some sort of chemotherapy.

This is one of those reports. Unfortunately, this bird also had metastatic disease at the time of treatment and it died after radiation due to its metastatic disease. Then there are various tumours of the head.

There's brain tumours, glioblastomas, astrocytomas, pituitary tumours, periocular tumours, cys adenomas have been described in many species. This is an African grey parrot that we saw with a cyst adenoma below its eye. This bird did quite well after we simply resected the mass.

So in summary, Treatment options for cancer and citizen birds are limited, but they are increasing with the more knowledge out there, more case reports, and more studies that are being done. The treatment currently, our, the treatment options are based on protocols used in small animals and in some cases that seems to be working well, but again, we don't, we have very limited studies on birds. There is success reported with chemotherapy, particularly things like lymphoma.

Birds, at least in the case reports and in the few studies that have been done, they seem to tolerate radiation well. There are not very many descriptions, if any at all, of radiation, adverse effects. And finally, surgical excision is often curative when possible, depending on the tumour type.

So, I thank you very much for your attention and I hope this has helped you in your future treatment of cancer in birds.