The lump began where his pectoral fin joined his body, just below the gill plate, and stretched to the bottom of his fin.
This started quite innocently, unfortunately due to his colour, it was impossible to photograph.
However, the lump became quite aggressive and grew in size until it was affecting his movement.
At this point, I brought him to a vet, who referred us to a specialist vet, who deals with fish, who was wonderful enough to make a house call to take a look.
He was of the opinion that operating was the best course of action, however it was quite risky, due to the location of the lump, and due to anaesthesia being required. I would need to make the decision on whether to operate or wait and see.
After much thought and discussion on forums, I made the decision that operating was necessary - which turned out to be the best course of action as the lump then developed to this:
So the arrangements were put in place for Genghis's operation, the vet would come to my house on Saturday morning and anaesthesize, operate, and hopefully Genghis would resuscitate and recover.
The vet set up on our kitchen table while I chased Genghis around the tank with a net ( he became immediately suspicious upon seeing buckets and recovery tanks being set up).
Genghis was given anaesthetic in 6 pints of water (knew my Gussie Goldfish Bowl would come in useful for something eventually) It did take some time for him to eventually go to sleep, but when he did, he went from swimming to floating on his side almost immediately.
On the operating table. The lump is being held in a forceps.
Cutting the lump off with a scissors. The vet was working very quickly, as the less time he's out of the water, the better.
Remainder of the lump being removed, this was the most nerve-wracking part for me, as it was connected to his fin.
Lump removed, and a bit of bleeding at this point.
Genghis and his lump, for size comparisons.
Cauterizing the wound. This did smell pretty bad :(
Wound cauterized, and Genghis is ready to go into the recovery tank to resuscitate.
The removed lump which is being sent to a lab for a biopsy.
Now, the next tricky part.
Genghis was transferred to a separate tank with an airstone, as the oxygenated water should help him come around.
After a few minutes of floating, we went almost immediately from unconscious to swimming about, so the second riskiest part of the operation was over.
He still has some healing to do, but with clean water and good diet, I hope this will only take a short while.
His fin is still rather weak, as he has not been able to use it properly for a month now, and it will be tender after the operation, but he is already making efforts at using it.
The morning after, already looking much improved.
Overall, an educational experience, but not one either of us want to repeat.
UPDATE 29/06/12
Unfortunately, the tumour reoccurred aggressively, and while it may have been possible to remove, poor Genghis was just too unwell to attempt operating.
On the day the operation was scheduled, he stopped attempting to swim, and was not eating. He had also developed reddened gills, and cataracts on both eyes.
The decision was made that perhaps it would be in his best interests to put him to sleep.
He was anesthesised, and then an additional dose of anesthetic added, so his discomfort was minimised.
