tpvets_logo.jpg (2726 bytes)TOA PAYOH VETS   Blk 1002, Toa Payoh Lor 8, 01-1477, Singapore 319074   Tel: 6254-3326, 9668-6469, 9668-6468.  
19 August, 2015
  Focus: Small animals - dogs, cats, guinea pigs, hamsters, turtles & rabbits

 Toa Payoh Vets
Clinical Research

Veterinary Advices

Dr Sing Kong Yuen, BVMS (Glasgow), MRCVS
First written: 15 October, 2011
19 August, 2015
2011 Case

"When the hamster's tumour starts to bleed, bring her to me and I will put her to sleep, Vet 1 advised us," the mother brought her teenaged daughter and her hamster to me today 11.30 am, Friday Oct 7, 2011. "I consulted Vet 1 three days ago and my daughter has been crying since."

Vet 1 had said that the dwarf hamster, being 2 years old, would die under anaesthesia and surgery. Therefore, wait till her abdominal tumour bleeds, to bring the hamster in to be euthanased. The mother could have surfed the internet and phoned me.

dwarf hamster, 2 years, female, zoletil, large subcutaneous tumour, toapayohvets, singapore"It is not a guarantee that all dwarf hamsters with tumours will die under general anaesthesia," I don't understand why Vet 1 would not have asked the owner to see other vets if Vet 1 would not perform surgery. I just rejected a koi owner who phoned up to ask if I treat kois. It is the right thing to do and is in the interest of the animal. Not to advise waiting till the tumour bleeds and bring the hamster down for euthanasia.

"Much depends on the health of the hamster, the size of the tumour and the duration of anaesthesia," I happened to pick up the phone today as I was in the Surgery to interview a job applicant who wanted to work with animals and teach 3 Temasek Polytechnic volunteers on cases involving an old Maltese with cystitis, a stray cat with FIV and a puppy on an IV drip, amongst other pets.

"How big is the tumour and is it a breast tumour?" I asked. The mum did not know and spoke to the daughter. "It is best I examine the hamster."

"How much is the consultation fee?"

"$30.00," I said. "But you already had consulted Vet 1. The decision should be whether you would want to take the risk of this old hamster being operated and pay the operation and anaesthetic fee.

"If the hamster survives the operation, she lives another 6 months as dwarf hamsters live up to 2.5 years of age. If she is not operated, the tumour gets infected and bleeds as the hamster keeps nibbling it. Lots of blood stains and great distress for your daughter in the next few days, leading ultimately to death by lethal injection. In such cases, your daughter would be much traumatised after seeing the hamster suffer from bleeding all day long!"

It is extremely difficult to be a mother of young teenagers nowadays. I could see that the slim fair 14-year-old was from an elite school. The cream of the crop, now much distracted by her hamster's poor health. She did not know when the tumour developed and so whether it was fast-growing or not, it was difficult to say .

"My daughter has her examinations till Monday," the mother said. I could sympathise with her as she wanted her daughter to excel in the highly competitive academic environment. How could she revise her lessons when she cried daily as her beloved hamster had no hope of survival?

As a veterinarian, the best interest of the pet must be priority. If the vet cannot handle a case, refer to other vets or ask the owner to find another vet.dwarf hamster, 2 years, male, zoletil, large subcutaneous tumour, toapayohvets, singapore I don't treat birds and fishes and I don't accept such pets in the first place.

The dwarf hamster is old at 2 years of age, but she is full of energy. Weighed 36 gram and has an excellent appetite. Trying to escape when the cage door is lifted up. Big black eyes. Well endowed.

"The chances of surviving anaesthesia are 70%," I said to the mother who had asked if I provided services to euthanase the hamster to prevent pain and suffering.

"Did you hear that?" the mum asked the quiet girl.
"Quite a good chance of survival," I said.
"You had operated on hamster tumours?" she asked.
"Yes," I said.

dwarf hamster, 2 years, male, zoletil, large subcutaneous tumour, toapayohvets, singaporeThe 3 Temasek Poly students, Dr Vanessa, Mr Min and I attended to the dwarf hamster. "This is a case where Zoletil sedation is needed as isoflurane + oxygen gas will not give you sufficient time to excise and stitch up in less than 5 minutes."

I said to Dr Vanessa, "With Zoletil sedation, you have around 5 minutes of surgical anaesthesia to complete the surgery. But you can top up with isoflurane gas." I told Mr Min to switch on the gas, just in case.

"All the theories of dosage per kg in vet books are not applicable usually in the real practice," I said to the 3 students - a young man and two young ladies. "This dwarf hamster weighs 36 g. How many ml of Zoletil to give without killing her? This is why many vets all over the world do not like to anaesthesize hamsters. The safety range is very narrow."

I got the Zoletil 50 ready. Two one-ml syringes were placed on the table. Mr Min got me a 25G needle which I told him was inappropriate.

I got 2 drops of Zoletil from a syringe. "These would not even fill up 0.01 ml of the syringe," I said. "I will add normal saline 0.05 ml," I said. "Just a little bit to top up to 0.05ml."

This dwarf hamster has no bulky backside muscles like the dog or cat or even a rabbit. So, intramuscular injection (IM) of the Zoletil was deemed not possible.

I stretched out the hamster's left hind leg while my assistant Min held the front body. I pointed the 25G needle at the appropriate backside and injected.

"If the hamster does not go groggy within 1 minute of injection," I said to the students. "It means the dosage was insufficient or that I had not injected directly into the muscle."

The students were very silent. Within 60 seconds, the dwarf hamster went down on her side. "I have less than 5 minutes to complete the excision of the tumour without isoflurane gas," I said. Everything has been prepared for surgery.

I use a scalpel, nicked the tumour for 0.8 mm long, undermined the tissues, clamped the lower stalk. Then I used the scalpel to excise off the lump. The hamster moved a bit as the anaesthesia was lighter.

It is extremely difficult to get the ideal dosage without causing death as the hamster is so small," I said to one student who later commented that the hamster had moved during the stitching up. "This high anaesthetic risk is the reason why many vets do not want to do surgery to remove big tumours."

The 3 students had a rare opportunity to see the whole process from pre-op to post-op.


Sometimes it may be wise to pass up a case rather than to offer unacceptable veterinary advices as they do stress out the hamster owner and force her family members or mother to seek another opinion.

If you add value to the hamster owner by offering alternative advices other than unacceptable advices, you may retain the goodwill. However, some of the younger generation just surf the web to look for "hamster vets" when the tumours get larger as in the 2015 case written below.

2015 Case

Two brothers in their 20s, brought in a hardy hamster on this May 1, 2015, Labour Day.

The hamster was thin and weighed 33 g instead of the average 45 g. He has two black ulcerated tumours. One below the chest at 2 cm x 2 cm and the other below the left armpit at 8 mm x 6 mm.

"Why didn't you get the tumour removed when it is small?" I asked.

"We asked a vet and he said to leave it alone," the elder brother said that the tumours were present for around 2 months and could be cancerous. As the hamster exercised, the lower part of the tumour got worn out and became infected and now blackened.

I checked the thin hamster's teeth. He had short teeth indicating that he was still eating to survive.

"He had lost a lot of weight," I said. "He does eat judging by his short front teeth being worn out, but he lost weight due to the stress and the tumours sucking up the nutrients." 

The elder brother had googled " hamster tumour surgery" or something like that and found Toa Payoh Vets' article on hamster tumours at:
Post-surgery advices on hamster tumour surgery
Dwarf Hamster-large fat tumour. Toa Payoh Vets
Hamster, 2 years, Massive subcutaneous tumour excised. Toa Payoh Vets

Now, the hamster is so thin, the anesthetic risk is very high. If he can survive the anaesthesia, he would be OK with the chest tumour removed first as the left armpit tumour is large too. There would be insufficient skin to stitch up if both tumours are removed. In any case, the chest tumour can be sliced off in 2 seconds as it is now loose under the skin.

April 2015 Video: Two brothers brought in a dwarf hamster with two large skin lumps - chest and elbow lumps 1/2

April 2015 Video: Large chest tumour excised 2/2
Blog: A hardy dwarf hamster with two skin lumps
Jun 2015 Video: Typical cases seen at Toa Payoh Vets. Three inpatient hamsters (eyelid abscess, skin tumour, bite wound) and a terrapin with swollen and closed eyes
Mar 2015 Video: A hamster has a large subcutaneous tumour (Mandarin)
May 2014 Video: Pre-op examination of a white hamster with a skin tumour 1/3
May 2014 Video: Zoletil Anaesthesia to excise a fast-growing tumour below the white hamster's ear 2/3
May 2014 Video: A fast-growing tumour below the right ear had been excised at Toa Payoh Vets 3/3
Nov 2013 Video: A Roborovski has a gigantic skin tumour 1/4
Nov 2013 Video: Equipment and drugs for anaesthesia & surgery for Roborovski's tumour excision 2/4
Nov 2013 Video. Surgical glove tip used as anaesthetic mask for hamster & electro-surgery 3/4
Nov 2013 Video: The roborovski's tumour is well after a large skin tumour removal 4/4
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More Hamster Tumour cases
The non-mobile older version of this webpage is at:
2011 case:  Unacceptable Veterinary Advices

Vets who do not wish to operate on hamster tumours as anaesthesia is highly risky in such small creatures, will do the owner a good service by referring him to another vet who does it. 

If a vet advises the owner to euthanase the hamster when the lump continues to grow bigger later, this is an unacceptable advice for the owner who may surf the internet for help. Most lumps can be removed by surgery if done early.

For other clinical research cases, go to:

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