I'm Dr. Sue, Cancer Vet, and I'm here to share another story of one of my Stelfonta cases.

I think it's really helpful to see a case go from treatment to week four for follow-up, just to see what goes on with him, because those pictures, what to expect, are hopefully gonna help you make the decision whether or not Stelfonta is the right treatment option for you if your veterinarian tells you that your dog is a candidate for Stelfonta.

So be sure to check out Vlog 130, because it has so much information about Stelfonta.

So let me tell you about beautiful, gorgeous Teddy.

He is one beautiful dog.

He is a six-year-old golden retriever, and I met Teddy to find out some treatment options for his mast cell tumor.

He originally had a mast taken off the top of his head in August of 2020.

Unfortunately, it was not submitted for biopsy, so we didn't know what it was at the time.

It did grow back a couple of months later and was taken off.

He had a second surgery in December of 2020, so about four months later, and at that time, it was determined that it was a grade two, high-grade mast cell tumor.

So there's those two grading systems for the mast cell tumor.

Be sure to check out, I'll put the link below for my mast cell tumor vlog, where I talk about the different grading systems.

So it grew back a month later in January, kind of at the edge of the incision, sort of right over the ear pinna, the base of the ear pinna.

And then she came to see me in the beginning of January, and this was a big mast, and it measured about seven centimeters.

When I did a preliminary assessment of his tumor volume,

I knew that it would be too big for Stelfonta.

It was greater than 10 cubic centimeters, which again, in vlog 130, I talk about as the requirement is the cutoff for being a candidate for Stelfonta.

But I thought maybe I could use steroids to shrink the mast cell tumor and get it into that size requirement.

So I started him on steroids and I had him come back,

I think about eight or 10 days later.

It had a really good response to the prednisone.

And when he came back in and we measured it, it was about two and a half centimeter diameter, and the tumor volume on the day of treatment when he came in was 4.2 cubic centimeters, definitely below the 10 cubic centimeters.

So let me show you his treatment, because his treatment, Teddy's such a good boy, was beautiful.

You know, if you're a veterinary professional, you know, we talk about you wanna use a lure lock syringe, you're gonna use a 23 gauge needle, and you wanna put, when you inject, it's a single injection and you're gonna fan it throughout the tumor, because you wanna distribute the Stelfonta throughout the entire tumor in one injection.

Teddy, just wonderful patient.

So let me show you his injection.

I'll be right back.

Hi, Teddy.

Are you ready for Stelfonta?

Hi there, we're here with Teddy.

He has a recurrent mast cell tumor in a very challenging location to be able to get margin.

So we're treating him with Stelfonta.

His tumor volume length times width times height times a half was 4.2, and so they get half that of the Stelfonta, so he's getting 2.1 ml.

We're gonna do a single injection.

We're doing a 23 gauge needle with a lure lock syringe.

It does sting a little, so we recommend that it goes up to room temperature.

All right, ready, buddy?

All right, here we go.

And then we're just gonna take it and fan the dose throughout the tumor to get it.

All right, here we go.

Good boy.

All right there, buddy.

Good boy.

Good boy.

You want a treat?

Yes, that was so good.

So I keep in close touch with my patients following Stelfonta.

I ask them to send me pictures, especially these early cases.

I wanted to document them.

And Teddy's mom and I follow each other on Instagram.

So she was sending me some direct messages.

And you know, he's having some swelling as we expect in the area.

And I actually had her come in a couple of days earlier.

And remember for Stelfonta, we expect inflammation and we expect oncolysis, so rupture of these cancer cells.

But what with him is we were noticing that there was sort of a pocket under the side of his face.

And when he came in, when I pressed on that, we noticed that there was some pus purulent discharge.

And I told you that most dogs, we take a hands-off approach.

We don't use antibiotics.

We don't flush and things like that.

But I did make an exception to the rule.

So, you know, we have to use our assessment.

We have to use our judgment as clinicians.

And I did flush his out because I was worried that as his tumor was dying and necrosing that it was getting trapped under there.

And I did do a short course of antibiotics for Teddy.

So an exception to the rule there.

So again, we usually check at day seven and then at day 28.

He, mom was very happy.

Things dried up.

He was really, really improving.

Hi everyone.

So we're here with Teddy.

He's about four weeks after his Delfonda treatment.

Oh, he's so perfect.

Looks great.

Look how beautifully he healed up.

He has this little area right here that I just did an Asper trying to determine if he had a complete response.

When he came in on day 28, there was a 0.8 centimeter mass.

When you see a mass, you know, little different than Tucker, who's in the one of the other previous vlogs that I have as a case study.

You don't know if it's just some scar tissue or if it's residual mast cell tumor.

So what do you think I'm going to do to figure out whether there's tumor there or if it's just healing scar?

Of course, we're going to Asperate, collect some cells and look at them under the microscope.

And so on day 28, we did determine that there was residual tumor there.

I looked at it myself, saw mast cells, also sent it out to the lab and the cytologist confirmed it as well.

With Delfonda, we have a 75% complete response rate with one treatment.

For dogs that get one or two treatments, the complete response rate goes up to 87%.

And we want to wait a full four weeks before we do a repeat treatment.

So I set Teddy up to come back in next week for a repeat treatment.

They need to start their steroids at least two days before treatment.

And when he came back in after being on steroids for two days,

I felt around, felt around, felt around and I could not find his mast cell tumor.

And if you can't find a mast cell tumor and you can't measure tumor volume, you can't inject Delfonda.

So we're going to taper Teddy off of his steroids.

He did not get a repeat Delfonda injection.

I'm apprehensive that there, you know, his mast cell tumor is going to grow back, that there's still some cells there, but he didn't get a repeat treatment and mom was pretty happy about that.

His also was a subgrade high, was that high grade, grade two high mast cell tumor.

So I do think he has more risk for metastasis.

So for him, unlike some of the cytologic low grade mast cell tumors, for Teddy, we are considering chemotherapy as well.

Again, I have more information about the overall how we manage mast cell tumors in my mast cell tumor vlog.

There's a two part vlog and we'll put links below so you can follow up on those.

But again, I hope this was helpful to kind of see a patient go through the process, see their treatment, see their injection.

And like I said, most dogs, very hands-off approach.

We are not going to use e-collars, not going to do antibiotics.

Their wounds are going to be left untouched and just really minimal management.

Teddy's an exception to a rule.

So again, if you have questions or concerns about how your dog is doing after Stelfonta, reach out to your veterinarian.

Thanks so much for watching.

I'm really excited.

I will continue to share these cases with you as we treat them.

I've treated a handful, a good number of cases so far.

And as I capture the videos, I will share them with you.

Thanks so much for watching.

I'll see you at the next video.

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