It was a big deal when this golden retriever completed his chemotherapy treatment, so when the big day finally arrived, he was rewarded with the most adorable graduation ceremony imaginable.

TikTok user Brenna Stout (@brennastout) from Orange County, California, shared the footage of her English cream retriever, named Dunder, as he was applauded by several members of the veterinary clinic for finishing chemotherapy treatment.

While making the most of his graduation ceremony, the 6-year-old pup sported his very own mortarboard and was rewarded with a special dog cake just for him. Needless to say, there was nothing wrong with his appetite and he lapped up every last crumb of his delicious treat.

The adorable clip has melted hearts across the internet and there's hardly a dry eye left on social media. Since it was posted on May 29, the video has amassed more than 5.9 million views and over 1.7 million likes on TikTok.

The caption alongside the video reads: "We're so proud of him, we love you Dunder!"

Chemotherapy for Dogs

According to PetMD, the chemotherapy drugs for dogs come in three main forms, which are oral medications, injections, and infusions. Dunder went through vinblastine infusions, but his owner said on TikTok that it "had very few side effects."

Treatment usually lasts for several weeks or months across numerous sessions. PetMD notes that the most common side effect of chemotherapy in dogs is gastrointestinal upset which leads to poor appetite or vomiting. That usually happens within three days of treatment and usually lasts up to five days.

Alternatively, other side effects include suppression of the bone marrow, susceptibility to infections such as pneumonia, and much less common is hair loss.

Unlike cancer treatment for people, chemotherapy doesn't usually cure cancer in dogs. Instead, veterinarians often judge its success by whether the cancer's progression slows down, the pet's quality of life during treatment, and how long they survive after.

How Did TikTok React?

Seeing the moment Dunder "graduated chemotherapy" and was finally "cancer free" has delighted millions of people online. TikTok users were full of praise and congratulatory messages for the brave retriever, as many people were so grateful that he got this special moment.

After the sweet clip went viral online, Stout even shared a follow-up video thanking everyone for their support and kind messages for Dunder.

With over 5,100 comments on the viral TikTok post already, Dunder's graduation delighted plenty of people and left many others in tears. One comment reads: "Please tell him everyone on TikTok loves him and we're proud of him."

Another TikTok user responded: "CONGRATULATIONS DUNDER."

One person wrote: "The absolute best thing on TikTok."

While another comment says: "AWEE his SMILE I'm actually crying. Dogs shouldn't be allowed to get cancer."

Newsweek reached out to @brennastout via TikTok and email for comment. We could not verify the details of the case.

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