Hello everyone, and thank you very much for joining me while I discuss anal sac apocrine gland adenocarcinomas. And while I'm not an oncologist, I hope I can bring a some insight into how to manage these tumours. So we're gonna discuss all things, anal sac adenocarcinomas have, so we're gonna discuss the presentation, the clinical signs, diagnosis, any paraoplastic syndromes, how to stage these patients so we can see what's exactly what's going on.

Surgery in histopathology, chemotherapy, and then palliative care. So what is anal sac epocrine gland adenocarcinoma? Well, it's a malignant tumour and this arises from the secretory epithelium of the walls of the anal sacs and it can be uni or bilateral.

So there is a reported metastatic rate of 26 to 79% at the time of diagnosis. And local metastases are tend tend to be in the regional sublumbar lymph nodes, such as the medial iliac, sacral and pelvic area. Distant metastases which can occur months to years later, that can be in the lungs, liver, spleen or bone.

And occasionally extension from the iliac lymph nodes into the lumbar vertebrae may also be noted. So it's rare in cats, but any, the commonly represented canine breeds are Labradors, golden retrievers, cocker spaniels, springer spaniels, German shepherds and dachshunds. I will say that probably the, the majority of the patients that we treat, via surgery and then in oncology, are actually cocker spaniels.

The reported median age for dogs is 9 to 11 years and about 12 years old in cats. So a lot of these tumours are detected in apparently healthy dogs. 40% of patients were, it was an incidental finding, at a routine examination, such as like a booster or just a wellness examination.

And only a third of these patients may show signs of being unwell. So clinical signs may vary and are related to the size of the primary mass. Local lymph node metastasis and the presence of paraineoplastic hypercalcemia.

But as I said, lots of these patients are do appear to be really well. So signs include perianal swelling. So we, need to do careful rectal palpation, because of 50% of these tumours are not actually detectable on external examination alone.

So if these guys are coming in for boosters or for anal gland expression, a careful examination is required. Not all of them are, as, as large as in the picture, at the bottom of the screen. Some patients may end up with faecal tenesmus and possibly some flattened faeces, and this is due to the mass some of the enlarged sublumbar lymph nodes or potentially the primary mass causing an obstruction.

They may end up with some hind limb weakness, they may end up PUPD due to hypercalcemia. They may also be lethargic, and there may also be some weight loss. Diagnosis can be made with an FNA of the mass and then submitting to cytology.

So these cells are usually exfoliate in quite large clusters, and they have a moderate amount of pale basophilic cytoplasm. And they have a round or oval nucleus. So the cytoplasmic margins of these cells are also poorly defined as you can see in the picture, they're all kind of like mushing into each other a little bit.

And these neoplastic cells may present a kind of like in a rosette shape, so you can see like they're almost kind of circular here. And for the FNAs we would tend to just use a 23 gauge 5/8 needle, . And then use a 5 mil syringe just to kind of pop all of that sample onto a onto a slide.

For in-house examination, we just use Diff quick to stay in the smears, just for our, if we're checking to make sure we've got, suitable samples before we send off to external labs. So the paraneoplastic syndrome that we would mainly be concerned with with these guys is hypercalcemia. And this occurs in approximately 25 to 53% of patients, and it can be associated with a decreased survival time unfortunately.

So total calcium on a biochemistry test may actually be normal. And so we're looking ideally for the ionised calcium, which is the active form, as this may be elevated. This occurs due to the parathyroid hormone related peptide or PTHRP being produced and secreted by the tumour.

So PTHRP is a hormone that causes blood calcium levels to increase, and this is completely unrelated or independent of the normal PTH. This causes calcium to be retained by the kidneys, so decrease in the amount that is excreted in the urine. It inhibits calcium deposits in the bone by osteoblasts, and it encourages the osteolasts to withdraw calcium from bones.

So this results in a pseudo hyperparathyroidism or hypercalcemia of malignancy. So signs associated with hypercalcemia should resolve within a couple of days if all of the tumour is removed during surgery. Any persistent or or reoccurrence of the hypercalcemia, can be indicative of metastatic disease.

So if we've done surgery, we've followed all the protocols, and then, months later, there seems to be then . Hypercalcemia starts to reoccur, then we do need to investigate it again. So we, we would like to do some renal assessment .

Hypercalcemia and renal mineralization can lead to an acute kidney injury. So for staging, both glands should be assessed. The primary mass should be measured with callipers and recorded, it can be quite difficult, especially when you're trying to get the depth of what if you can get as accurate as measurement as possible.

All the regional lymph nodes should be assessed and measured. And we also then should be checking for any distant metastases mainly in the thorax. So the primary mass size, plus any regional or distant metastases can actually influence the prognosis.

And Poulton and Braley came up with a table which determines the stages of the tumour and then compares the primary tumour status and their size and any regional or distant metastases to actually then come up with a mean survival time. So staging should involve, we would normally just do a full biochemistry and haematology, we want a baseline for all results. We would do an ionised calcium to assess that as well.

And we will do, if, if do an FNA or for cytology of the mass, but most of the time this has already been done by by the time of presenting to us, but this is something that should be done. So for us for diagnostic imaging, we would ideally go for, we could start in, if without a CT being available, we could do anaesthesia for inflated thoracic views, and then follow on with an abdominal ultrasound, or we could do some abdominal X-rays as well, cause that will make, maybe be able to, visualise any enlarged lymph nodes. We have CT available, so ideally what we would do is an anaesthesia for inflated thoracic CT with contrast, followed by abdominal CT with contrast as well.

So if we're looking at a CT thorax, ideally we would like an anaesthesia. This means that we can get some inflated thoracic views, which, highlights metastases better. And we would then use contrast, and this, again, to highlight any metastases.

We would check renal function before, contrast, and then 4 hours of fluid therapy following on as well. And as you can see in this, in the, the pictures, this was an 8 year old Labradoodle, who, on the Who did show with increased size of pulmonary nodules compared from March on the right to May on the left. So if we're doing a CT of the abdomen, we would want the full abdomen to include the pelvis and to make sure that this is because we want to make sure we've got all of the anal sac and all of the lymph nodes in as well.

And we can administer contrast as well, just to highlight the tumour and any metastases. So this picture is an eight year old male neuter cocker spaniel, and he had bilateral tumours and the, and the most enormous sublumbar lymph node that was wrapped around the aorta and cadal vena cava. So this guy was non-surgical.

We, we, we kind of did some a little bit of chemotherapy with him just to try and, slow down progression, but this lymph node is absolutely enormous, I will never forget actually palpating that and thinking, oh my gosh, this, this poor dog. But you know what, this dog was super happy. If we're going to do some thoracic radiographs, er we wouldn't, this should involve anaesthesia for inflated views, and we would do left and right lateral and a DV.

As you can see, we can detect tho thoracic thoracic metastases in a dog with radiographs. Radiography is not as sensitive as CT, but it will show it if it's, if it's, advanced. Abdominal ultrasound can follow on radiographs and the CT.

So if we've done radiographs, we would want a full abdominal scan to assess lymph node size, and then to be able to take samples of any lymph nodes, the liver and the spleen. We also want some measurements of those sublumbar lymph nodes, so that we can measure, and then we can, we've got a baseline for where we are at this point. Any metastatic lymph nodes are likely to be enlarged.

So if we're, if they're enlarged, we can try and sample them to see, it means we can get a better plan of action for surgery. Blood typing is some is sometimes carried out as well. It's a test that you can do in-house to submit out to the lab, and it just means that you've got, you can plan ahead just in case you think actually we're going into this dog's abdomen, there is a risk of Ex excess blood loss during the surgery, and it means that you can have either the blood in stock or you can have a donor, an appropriate donor on standby.

So for anaesthesia and analgesia for surgery, I got some tips from one of our anaesthetists. So he, he, he likes to use a, a pre-medication with an alpha 2, and then a little bit of methadone as well, so 0.2 milligramme per kilogramme.

This can always be increased if required. Any induction agent and any maintenance agent really, although propofol induction and maintenance may have the best profile for cancer patients. He likes to use an epidural analgesia with bpacaine as this can provide analgesia for about 6 to 12 hours, and it doesn't it shouldn't have any effects on the motor function of the legs.

So we've got once we can get these patients up and moving around again, that'd be great. Also good analgesia also improves cancer outcomes as well. And we will we'll use also a non-steroidal as well as er possibly paracetamol at the same time.

So if these guys are coming in and they're hypercalcemic, ideally we would kind of want them on some, saline prior to anaesthesia and for surgery, just to try and reduce that calcium preoperatively. So sometimes we'll have them admitted the night before, or as soon as they're hospitalised in the morning of the surgery, we'll get them on some saline. We wouldn't go ahead and treat the hypercalcemia pre-op, as this is hopefully returned to, we won't treat too, aggressively with, with other treatments, as hopefully this calcium should return to normal post-op once the tumour has been removed, and we don't want to cause any other complications.

So if these guys have had an epidural, . It can it can provide analgesia for about 12 to 24 hours, depending on the combination. We need to monitor their urine, make sure that they can actually er pass urine, cos they may, they end up with some of them can end up with urinary retention.

So they need may need their bladder expressing. Ongoing pain scoring as well. Even if the epidural was effective, as noted during the surgery, we still need to make sure we don't know exactly how long that is going to last.

So we want to make sure that we are, we're, we're ready for it, to actually then start providing, additional analgesia as well. And we'd do some fluid therapy during this procedure and post-op as well. So into surgery, we would go for excision of the primary mass.

We want that all out of there. These tumours are often highly infiltrative and occasionally can invade the rectal wall, so it may require partial resection of the mucosa at that site, so we just need to be really careful around there and hopefully there's there will be no perforation. Sometimes the anal sphincter may need to be partly removed as well, depending on the extent of the, of the tumour, which may lead to some short-term faecal incontinence post-op as well, but long term it doesn't seem to really be a concern.

So if we've detected metastatic lymph nodes, we've had, we've sampled them following ultrasound, and we've determined that these are metastatic, we will also want to try and remove them at, at the time of surgery as well, if possible, as this can improve survival times. As we saw in that other picture, . From the from the abdominal CT, any substantial lymph node enlargement or anything that is involved with the aorta and vena cava may rule out that we're not actually able to do anything with that lymph with them lymph nodes, so they may just, they just have to stay put.

So where we're going is to get some tips from, one of a surgeon as well. So she always likes to place a pursing, purse string suture, hopefully to minimise any contamination, of the surgical site. And you need to make sure that you do place it so that you can still access the entrance to the, to the ducts.

Margin wise, unless it's a really small tumour, it's usually not possible to get a massively clean margins. And then repairing rec rectal perforations is a nightmare. So she usually likes to stick as close to the mass as possible, rather than actually trying to get massive, massive margins.

And then make sure that you change the kit, your surgical kit and gloves before you actually close, just so that you are closing with fresh, fresh, fresh kit. So for post-op care, we need to make sure we're going ongoing pain scoring as well. So if we know that epidural work really well, but we know it's potentially going to wear off at such and such a time, we would like to start, we start to provide the additional analgesia just before that starts to run out, and then monitor and continue pain scoring every 4 hours with the analgesia as required.

Monitor for faecal incontinence, in the hospital as well. As I said, it can, it can happen postoperatively, but hopefully shouldn't be a problem longer term. But if there is any faecal incontinence, we need to make sure that the wound and that perianal area is kept clean.

Hopefully, it's not diarrhoea. But it, and the faeces that the patients that I, I've dealt with that have ended up with incontinence, the faeces does tend to be of a normal consistency, so it's trying to keep the wounds it clean isn't too difficult. And then a buster collar as well to prevent wound trauma as well.

So these tumours we want to send off for histopathology, and then this can confirm that it is indeed an anal sac adenocarcinoma, and that can actually then give us some information on surgical margins as well. So it's reported that 20 to 50% of tumours occur following reoccur following surgery. And this is a potential risk if then surgical mar margins are incomplete.

So patients that do have incomplete margins should follow it with adjuvant treatment, and this is just to prevent any local reoccurrence or metastasis, and this could be in the form of chemotherapy, radiation, or electro chemotherapy as well. We can start once the surgical wounds have healed up, for about 10 to 14 days post-op. And everything that we use for, chemotherapy, and anything else is all off licence.

So we do need to make sure that the owners are aware and on board with all of that. So there are many agents that have been investigated for both the adjuvant and palliative management of these tumours. So we have carboplatin, mitoxantrone as single agent treatments, or carboplatin and mitoxantrone as an alternating treatment.

There's melphalan, palladia, cisplatin and actinomycin D. So our protocol for what we routinely start these guys on is carboplatin, and the dose is 250 to 300 milligramme per metre squared, and it's given us an IV infusion. We tend to start lower, so we can assess any side effects and the neutrophil dare as well.

And which we, we tend to do the neutrophilnada Nade about 10 days post administration. It tends to be given every every 3 weeks, but we may need to extend it to 4 weeks if there is neutropenia. We base this on ideal body weight, and then we're basing it on the body surface area as well to try and minimise the risk of side effects.

We tend to go for 4 to 6 treatments, and so the infusion is given IV and it needs to be given by a first or clean stick IV that has, that has been placed clean stick. Carboplatin is highly irritant if if it extra visa is. We administer over 15 to 20 minutes alongside a normal saline.

We also administer Mirropotent on the day of treatment and for another 3 days post, regardless of how the pet is. This is we, it is just easier to try and prevent any problems rather than trying to catch up. We, we provide the owner with some metronidazole to.

So that they can actually start that if there is any diarrhoea that is ongoing following the chemotherapy. And we tell them if they have maybe one or two bouts and it's, and then it clears up really quickly, that's fine. If it's ongoing, or it's, it is really bad, they can start the, the metronidazole straight away.

And we monitor the urine and creatinine prior to each treatment as carboplatin is can potentially be nephrotoxic. And then we will want to restage partway through as well to make sure that the chemotherapy is actually doing its job and that there is no disease progression. So if we were doing 4 treatments, we may do, we may restage maybe at the before the 4th treatment.

And this can either be with a full anaesthesia for CT and ultrasound, or sometimes it is just a conscious focal lymph node ultrasound just to assess the size. So the side effects of carboplatin, there are GI side effects, so vomiting and nausea. So as I said before, we would always administer Murropotin prior to chemotherapy, and then give the owners a couple of days, maybe up to 33 days' worth at least to carry on with at home.

And then make sure that they've got plenty at home as well so that if they do need to administer another dose, in between, they have got everything available. Diarrhoea may also occur, so as I said, we give them, we'll give the, we'll supply the owners with some metronidazole in case it's ongoing. So neutropenia does tend to be the major dose limiting toxicity of many of the chemotherapy agents and carboplatin can also cause this problem too.

So mild neutropenia is common, we see it all the time and it's often it's not a clinical problem, so, and patients tend not to even show any clinical signs. If the neutropenia is severe, and it can be complicated then by sepsis and maybe be life threatening. So patients that do have severe neutropenia will have clinical signs and should be treated as an emergency.

So if you know Pat has had chemotherapy. 10 days ago and then the owner calls up out of hours and says my pet is he's anorexic, he's lethargic, he's really, He's got some GI signs. He generally just feels, looks really rubbish.

He looks really, looks really unwell. We should be treating this as an emergency, and this is what we tell all of our, our night team, the nurses and the interns who are on overnight, is that, and if they, they know they've got access to all of our records, so if they, they can see that one of our patients was called out of hours and has all of these signs, they know that they need to see them as soon as possible. So we do a haematology blood test before each of these chemotherapy administrations, and then at that points following some of the following the treatment as well, which is the neutrophil the deer.

So the the Naira is the lowest point that the neutrophils will get to, following the administration of the treatment. So it's usually about 7 to 10 days following treatment, but carboplatin likes to mix it up a little bit and can have a double Nadea. So some people would recommend performing the Nadea haematology at week 12, and 3 following treatment.

Just so we can actually see what at what point the neutrophils are going up and down and, potentially gonna cause us any bother. We tend to just do it at day 10, and then when they're due back in at day 21 for their next treatment. So the Nade actually helps us plan for that next dose of treatment.

So if they come in at day 10 and the neutrophils are within normal limits, we will either dose increase or we'll keep that dose the same. If that pet is neutropenic at day 10, . We will probably either just dose decrease next time.

So the level of neutropenia that that pet is at depends on the action that should be taken. So you have this little chart. So, if the neutrophil count is above 3, they're not new to peeing it.

They're good to go. If they're due chemotherapy, we would continue with the treatment as scheduled. If it's the Nadia, great.

It means that they're, they're absolutely fine, so they can continue with that same dose or we could increase it for next time. If the neutrophil count is between 2 and 3, and this is a mild neutropenia. So if they were due in for chemotherapy, we could do a manual count with a blood smear.

If it's, and sometimes it'll be low on a blood test machine, but actually when you do a manual count, it's normal and if that's, and if it is, that's great, we just go ahead with treatment. If the neutrophils are actually low on s on the blood smear as well, we will delay treatment and then rescheduled, and then reschedule maybe in a few days or a week or so afterwards, give that bone marrow a chance to recover. If this is the naira and they're a little bit low, this means that we might need to reduce the dose for next time.

So if the neutrophil count is between 1 and 2, this is a moderate level of neutropenia, so if they were in for treatment, we'd delay treatment, we wouldn't give any more chemo if, and then we'd reschedule, and then recheck maybe in a few days. We'd probably give them a broad spectrum covering antibiotic, as their immune system's not actually able to support the patient properly. If that patient is normothermic, there's no evidence of pyrexia, and they're not showing any of the clinical signs.

We will treat that patient at home. We will get them out of the hospital as quickly as we can. They're more likely to pick up something in the hospital than they will at home.

And so we tell owners, take them home, keep them in for a couple of days, maybe just garden exercise just for a little while, so that they they can't pick up anything from anywhere else. If that patient is showing clinical signs or is pyrexic, we probably need to then start hospitalising them. And if their neutrophil count is less than one, this is classed as a severe neutropenia.

Again, if that patient is not pyreexic and is not showing clinical signs, we will give them them antibiotics and get them out that door as quickly as we possibly can. We want them home, we don't, we want them as safe as possible. We will get the owners sometimes to monitor their temperature at home as well, and if they know if their temp if that patient's temperature starts to rise, then they can, they will contact us and we probably then will start to admit them.

If that patient is actually pyorexic, we will need to admit that patient for treatment, and we need to bury a nurse, that patient and isolate them from any other patients. It's mainly supportive care, so fluid therapy, electrolytes supplementation, such as potassium and IV medications, such as antiemetics, antipyretics, and antibiotics as well. We may need to consider feeding tubes for these guys, to make sure that they're getting sufficient er nutrition.

Neutropenia tends to rectify within a couple of days, anyways, it is, as I said, it is just supportive care getting them through this and within hopefully 24, 48 hours, their Neutrophils are back in their normal levels and when we can get these guys home. So we could go on to radiation following surgery. So we could use this as a treatment and for palliative care.

So for radiation, it can be used post-op for incomplete margins to control any microscopic disease and hopefully prevent any reoccurrence or regional spread. So there are side effects, to any of, any of the areas that the, the radiation comes into, is in contact with. So the skin and the lining of the colon or the rec and the rectum.

And these, these side effects can include burning, irritation, inflammation, and they may end up with diarrhoea for up to about 2 to 4 weeks post treatment. Radiation can also be used palliatively for inoperable tumours or for disease that's confined to the regional lymph nodes. It might slow down the progression of the disease, but it is rarely curative.

There's a lot, it's a lot less side effects than with the full course or the dose because the dose and the, the intensity is is reduced. So electrochemotherapy is another treatment that we can offer. It's a form of local cancer therapy, that where we would either, we would administer bleomycin as an IV injection.

And then we combine that with electric pulses that can cause reversible permealization of the cell membrane, and this enables the drugs that we've administered IV to get into the cells. So we would, in the picture, we have some plates, and we also have little spikes that we can actually admini Get through the skin into the tissues that were potentially affected. Requires anaesthesia or sedation, but there are risks remember associated with any anaesthesia or sedation.

So biliomycin can lead to pulmonary fibrosis, and the risks of this occurring can increase by administration of oxygen at the same time, so we tend to do all of our patients with sedation rather than anaesthesia, just to try and minimise that risk. So once that chemotherapy protocol has been completed, we recommend monthly rectal examinations at the primary care practise. And then they can come back to us every 3 months or so, and we will do the, re-staging then.

So we will be looking at the ionised calcium, to look at for, again, if, is there evidence of hypercalcemia reoccurring, as this gazette is, can indicate evidence of progression or reoccurrence of that disease. Sometimes we will just do a conscious focal ultrasound of them, some sub lumbar lymph nodes. Again, just looking at the size, if them if them lymph nodes looking like that they are starting to increase in size, we would probably go ahead then for sedation to get some samples.

Or we could go ahead with full chest X-rays, ultrasound or CT as well. So this patient came back for his monitoring scan, and this was, this was done all conscious. This patient had a left side anal sac tumour.

He had completed, he'd gone through surgery. He'd then gone through a chemotherapy protocol, gone up with, carried on with the follow-up protocols, and then eventually he, this guy came in. And this is his left, medial iliac lymph node.

And this indicated disease progression. So as you can see, this lymph node was enormous. It was, 5 centimetres by 3 centimetres.

And when you compare that to his normal. Unaffected right medial liilac lymph node, which is only 2 centimetres by 0.5 centimetre, it's obvious that there's there there is disease progression there.

So if there is disease progression, so such as for that patient, we could go for further surgery and to remove that metastatic, lymph node, and then a new chemotherapy protocol, we probably wouldn't then go for carboplatin, we would go for something, go for a different, a new, a new and different protocol. If this guy was was on a chemotherapy protocol and he'd showed evidence like this of progression, we would change the protocol. So we, and then we're gonna have a little chat about a case later on as well.

So for palliative care is an option for these guys either at any at any point in the diagnosis, following the diagnosis of anal sac adenocarcinoma. We need to discuss with the owners their expectations from palliative care, and what level of treatment that they are comfortable with. We need to make sure that that pet is the, the absolute top priority that we're, we're not skimping on anything, because we, we want him to have, them to just carry on as normal and be and be as well as possible, despite the, the, the condition.

We need to make sure that the owners know at what point that they would wish to stop. So it's, it's worth chatting with them and kind of getting them to start thinking, when would we want to stop? Would it be at the point that they require some extra analgesia, when they're not eating as much, when they're not enjoying exercise or not sociable anymore, they're, they're just kind of, what, at what point would they wish to stop any form of treatment and euthanize?

This can help them in the future when it everything kind of gets really difficult and, it just can kind of help give them a little bit of a plan. So they need to understand that palliative care is to keep their pet happy and comfortable, but we're not actually doing anything to treat the disease. We're treating all of the clinical signs to keep them well.

We're treating the nausea, anything else, any obstructions. We're, we're trying to, we're treating the side effects, not the disease. So every day we need to make, we need to weigh in that every day is an awesome day.

And with that, we need to make sure that the pet is free from all the sides, side effects of the disease. So, as I said, the, the faecal obstruction, which can be caused by the lymph nodes or that primary mass, and any, nausea or vomiting, or anything else that can, hypoorexia that can be caused by that hypercalcemia as well. And there is also the option of palliative radiation, if the owner would like to go ahead with something like that.

So we do have lots of quality of life scales, that are available. These are just two of them that I, I, I've come across, and I have put the links in the notes as well, if it's something you would like to look into. And this is something that we can get, we could get the owners to be filling in, maybe weekly or every 2 weeks.

Sometimes, even every couple of days, depending on, how their pace, their pet actually is. And this can sometimes actually. As they can start seeing changes that can actually then help them make the decision to either to discontinue treatment.

So faecal obstruction is a problem, and especially. If there is any of these massively enlarged sub lumbar lymph nodes or even this . Primary mass, lactulose can be used and this can so just just to soften the the the faecal mass, just to be able to make sure that it can get past that obstruction.

The effect of the treatment should be monitored, and the dose adjusted as required. We don't, we're not aiming for full on diarrhoea, we just want them faeces soft enough to actually be able to get past the obstruction, easily. So for hypercalcemia, the side effects from that can be nausea, hyperexia, renal disease, so we do need to be treating this as this can make them feel pretty, pretty crummy.

We can use a bisphosphonate, and this can be administered IV. And this is, this is used then to reduce calcium and any associated signs. So there's two options that I've used, and it's permidronate or zoledronate.

We use the zoledronate every 4 weeks. And we just, just be careful if there is any renal insufficiency or, and we always, we always do just monitor the urea creatinine before treatment as well. Doses is 0.1 to 0.25 MBK IV according to the BSAVA manual or formulary.

Some will start lower, some, some clinicians will start higher, and some will cap out at 4 milligrammes per patient, regardless of how, how big they are. We tend to, administer what they, whatever we. Come to by, by the dose.

So we can administer, so we dilute that the dose in 100 mLs of saline, or 50 mLs if it's just a small dog, and we administer this IV over 15 minutes via a pre-placed IV catheter, because it's a mild irritant if there is an extra visation. Some say by infusing, some saline, 30 minutes before and an hour after, it can help to safeguard against nephrotoxicity. .

Yeah. Prednisolone can also be used to promote calcioesis as well. And the salmon calcitonin can also be used, this tends, this is one, I've used this once in one patient, and this was the last line of treatment for this guy to try and actually reduce this massively high calcium, hypercalcemia that he had.

It does come with a risk of side effects such as anaphylaxis, especially when with repeated dosing, and this drug is super expensive as well, so it's it, it's not something we reach for, as a first line zoledronate does tend to work fairly well. And we also need to make sure we're on top of any nausea and hyperorexia as well, so we can use antiemetics, such as Mirropotent. The injectable is licenced for 5 days if required, and they're in the hospital, and the tablets are actually licenced for 14 days, 14 day administration.

We can also, so there is also the option of using, appetite stimulants, but we do need to make sure that we are using, that we've treated all of the other problems such as nausea, pain, and everything else before we go ahead and, administer appetite stimulants. So, as I said, I keep, I will keep going back to this, as a, as an oncology nurse, and then we see cancer patients day in, day out, and I say to all of my patients and to all of my owners that the quality of life for that pet is the most important thing for us to consider during the treatment. We need to make sure that they are happy during all of their treatments.

We got, even if it's the chemotherapy protocols or even just through palliative care, It's the most important thing to consider, we could throw all of the chemotherapy and everything at these dogs to and make them really, really poorly, even though their disease is completely under control and doing really well. They could be really, really poorly, and that's not acceptable for us. We want them to be really, really happy.

So remember we get these owners, yeah, we need to consider all of the joys that these pets have and all of these joys of life, all linking with the quality of life scales as well. So I'm gonna run through a case study, for one of the patients that came in to see us, coming up to 2 years ago. And this was an awesome, this he's an awesome staff he called Sid.

He was 11 years and 9 months old when he was first presented to us. So he was taken to his own vet's at the end of November 2019, as the owner had noticed a perianal mass, and the the the the veterinary surgeon noted a firm, non-painful, approximately 10 centimetre mass associated with the right anal sac, and they took some FNAs. So the er Sid was passing normal faeces and he wasn't straining at all, he was a really happy, he was just really happy little dog.

So cytology reveals an apocrine gland adenocarcinoma or the right anal sac. And he was then referred on to us at the oncology department at North West Veterinary Specialists for staging and then possible surgery. So he was, he eventually came towards mid December 2019, and he was, he was a really happy little dog.

He was bright and alert. He was eating and drinking fine. There was no polyuria, polydipsia.

He had been straining to defecate, so, but he had improved on some lactulose that had been given from the referring vets, in the, the week or so before he'd come, come to us. And as you can see, he does have a quite a substantial size right anal sac mass. So he was admitted and we did 90 calcium, which was normal, thankfully, it's given a better prognosis for him.

And all of his other biochemistry and haematology were also within normal limits, everything was fine, so he was suitable for anaesthesia, for CT and ultrasound and contrast. So we went ahead and did that. And the CT, the inflated thorax reveal.

The CT in revealed a mass of the in the right anal sac, which was consistent with the adenocarcinoma that had already been diagnosed. And they had detected the the sub lumbar lymph nodes as well, but they a little, maybe a little bit bigger, but they were maybe early metastatic or just reactive because of this massive anal sacer mass. But they look too small to sample currently.

So he, we went on and did an ultrasound following the CT as well, and again these these sub lumbar lymph nodes were way too small to sample. Just because of the risk of causing further, causing of the damage. So our surgeons assessed Sid and revealed that the excision of the mass would be possible, but it was unlikely to acquire clear clear margins, but the owner was wanted to go ahead.

So pre-surgery, . Sid had a pre-med of melatamidine and methadone IV via a pre-placed IV catheter. He was induced, anaesthesia was induced with alfaxolone, and he was maintained on isofluorine and oxygen.

He had a bpivacaine epidural, which worked really well, during the surgery. A purse string suture was placed using 30 ethylo. So during surgery, a small nodule was also, was found attached, but it was separate to the main mass, and it appeared to be embedded in that rectal wall.

So the primary mass and that little rectal nodule were removed, and then we were, they were submitted for histopathology. On recovery from surgery and anaesthesia, his bladder was manually emptied, so he wasn't sat there with a big, a large bladder, and because of the risk of urinary retention following the epidural, we wanted to make sure that his bladder was empty and he was nice and comfortable. And the purse string suture was also removed.

Sid was discharged the following day with paracetamol and meloxicam, and he did really well in recovery, and so was able to be discharged the following day. So histopathology, the primary mass revealed and had no carcinoma of the anal sac, which we were always, expecting. The neoplastic cells were infiltrating with a 0.1 millimetre of the sample margin, which is such a tiny, tiny, tiny, tiny amount.

So we didn't have clean margins. So this rectal, this, this little sneaky rectal nodule, was also a carcinoma, and this was compatible with the adenocarcinoma of the anal sac gland. So it was presumed to represent local invasion or metastasis of that primary mass.

So we saw it again mid January 2020, to, as a post-op check and to chat about what we wanted to do for, ongoing. So we had another conscious focal ultrasound of them some blood and lymph nodes. We just wanted to make sure there was no change to the size of them, medial ilap lymph nodes.

And, and there wasn't, thankfully. They, they were pretty much the same size, so there was no disease progression. So because there was an incomplete excision of them tumours, it was assumed that there was microscopic disease still remaining, so we recommended adjuvant chemotherapy and radiation.

Radiation was declined due to the risk of side effects, and so the owner was keen to get started with chemotherapy and we opted to go for 4 treatments of carboplatin. So the carboplatin, as said before ad is administered IV over 15 to 20 minutes with some 0.9% saline.

And we gave Sid some appotin prior to his first treatment and then the owner took another 3, had another couple of days for up to another 3 days for at home. And we supplied metronidazole for use as required. So his first dose was 250 milligramme per metre square carboplatin, and we did a neutrophil Nairra 11 days post treatment and that was within normal limits.

So the 2nd to 4th dose, because the Neutrophil the day following that first dose was normal, it meant that we could increase the dose to 300 milligramme per metre squared. We did another neutrophil Nadia following the 2nd dose, because this was the first time that we'd increased the dose, and that was also within normal limits, thankfully. So it meant that we could just keep, we could continue administering the carboplatin for the 3rd and 4th treatment at that increased dose.

So prior to the 4th dose, which was in mid March 2020, Sid was sedated for another abdominal ultrasound, and we, sampled his right medial iliac lymph node, because that was a little bit bigger again. There was no evidence of recurrence on the right side, and there was no changes at all to the last anal sac. We took FNAs also of his lever and spleen and that right medial iliac lymph node and there was no evidence of metastasis, yay.

So we went ahead and gave him his 4th and final carboplatin. We discharged Sid and he was to go to his own vet for monthly rectal examinations and then back to us in 3 months for an ultrasound again. So in June, he had sedation again.

The lymph, that lymph node is pretty much the same. It was the same size. Again, there was no evidence of recurrence on that right side and no changes to the left anal sac.

So again, we sent him away. Monthly rectal exams, and then back to us again in 3 months' time. So when he came back to us in September 2020, again, he was sedated for an ultrasound, so that right, .

So mediaac lymph node was sampled and it now did show evidence of metastases, and there was actually evidence of recurrence of the tumour on the right hand side as well, and there was a little there was a small nodule. But there again, there was no changes to that left anal sac. So at the end of September, he went ahead with further surgery and he had that right media iliac lymph node removed and that 1 centimetre rectal mass was also removed as well.

So in October 2020 following recovery of the surgery, we started with sort of ross terrob palladia, and we do a Monday, Wednesday, Friday protocol administration protocol, so, . And this is off licence, it's licenced for treatment for mast cell tumours, but it has been shown to be beneficial for patients with anal gland adenocarcinoma. So between October and April, he continued with this, and there was no evidence of disease progression.

He did really well with this. And then in April 2021, he started to struggle to pass faeces, and these were the faeces was coming out flattened. So this was evidence of disease progression again, so we decided to, to we obviously we discontinued the palladia.

And we started him with some mitoxantro chemotherapy, and he received 2 doses. At the end of May in 2021, he was presented again for his third Nitoxantrone, and again there was evidence of disease progression, and this was these sublumbar lymph nodes again increasing in size. So we had to discontinue the mitoxxandrome.

So we started him with Melphalan, and this is a 5 days' worth of treatment every 3 weeks. And he was also on intermittent use of meloxicam, hourly for for arthritis and its anti-cancer use as well. So he received two treatments of melphalan before the disease progression was detected again in July 2021.

So chemotherapy treatment was discontinued and palliative care was a palliative care plan was started for Little Sid. So we made sure that he had plenty of analgesia and that he was really comfortable. We started him with some lactulose that the owner, was just kind of the kind of admit was, that was administered, and we just again monitored to make sure that we weren't causing him any diarrhoea and that it was just that the faeces was at a consistency that he could pass easily.

And then we were made sure she had anti-nausea or antiemetics in the form of lots of serenia, so that she could administer that, and he could have that whenever he, he needed it. He was generally well in himself, and he just kind of, yeah, we just kind of carried on and just made sure that he was good and comfortable, bless him. He was such a sweet boy.

So all of the dogs, all of the owners that are on treatment for chemotherapy, we do give them lots of guidelines so that we know how to . They know what to expect once they start chemotherapy, how to handle a patients, how to handle all of their waste, any, lots of lots of information, and we also make sure that we prepare the owner for complications as well. So if you do need any help with any of your anal gland tumour patients, do give us a give us a call or contact your local friendly oncologist for all things chemotherapy or, to do with these tumours.

We at Northwest Veterinary Specialists are happy to do advice calls, for anything like this, or for any referral. And if you're wanting to go ahead with any chemotherapy yourself in practise, chemo are fantastic and they can advise you on doses and actually provide with you with what you need. So there's some further reading for you.

And I I I, I do always put this on because this is, this is so important for us as well, especially at this at this time, and make sure that you do look after yourself, as much as you can. And if you do have any questions, please do give me a call to shoot me an email, either to myself or to enquiries at NW Specialist.com.

And messages can either come to me or via or to the other on to the to the oncologist, and we can we'll. Do what we can to help you guys out. So thank you very much for listening and I hope you found this beneficial.

Thank you, bye.