This cat was presented with a visible abdominal mas. On ultrasound the mass seemed to be attached to the stomach and cytology showed multiple mast cell tumors. The mass was removed and came back as eosinophilic sclerotic granulomatous gastritis. This is an uncommon condition in cats, a result of parasites , and certain bacteria.  Most cases actually do not need surgican excisin and respond well to prednisolone.
For more info- http://vet.sagepub.com/content/46/1/63.long
 
This doggie was febrile and pretty sick, but did great once started on prednisone
 
The arrow is pointing to 2 small raised lesions on the toungue. Cytology revealed multiple eosinophils
 
This cat was presented to me after his owner noticed extensive bruising all over his abdomen.  After ruling out bleeding disorders a biopsy was taken and revealed lymphangiosarcoma. Lymphangiosarcoma is not common, and if caught early enough can be excized. This case was non-operable, and the cat had 3 chemotherapy treatments which have shrunk the tumor to an operable size. The tumor was removed succesfully but during the recovery period the cat developed a severe MRSA infection and was euthanized. 
 
This one is a ferral cat that belonged to a colony that was treated by one of my clients. It took her a while to be able to catch him and when she did it was too late. The diagnosis was osteosarcoma.
 
This dog was presented with an acute purpura.
After ruling out bleeding disorders a biopsy was taken and indicated vasculitis. 
Cutaneous vasculitis is an uncommon immune-mediated
inflammatory disease of the blood vessels. Aberrant immune
response leads to inflammation and necrosis of blood vessels.

 Possible causes in veterinary patients are an underlying
infection caused by a virus, bacteria (e.g. Bartonella species),
fungus, protozoa (e.g. Leishmania species2), or rickettsial
disease; food hypersensitivity; malignancy; drug reaction (e.g.
meloxicam, human albumin); rabies vaccination; metabolic
disease; systemic lupus erythematosus; and cold agglutinin
disease. The disease may also be idiopathic.

 
An 18 years old cat was presented with a mandibular abscess, and was treated with Intravenous antibiotics, fluids and pain medications.the abscess was lanced.
Over the course of the next few hours an area of discolored skin developed over the abscess. Due to the quick development the cat was taken to surgery and a very aggressive debridenent was done. The histopathology results were compatible with necrotizing fasciitis which is a life threatening condition which is also known as " the flash eating bacteria".
To read more about this case follow this link
 
A 5 years old DSH male neutered cat was presented due to a non healing uveitis of the left eye.  Enucleation was performed and the histopathology results indicated ocular lymphoma. Ocular lymphoma in cats can be primary, and in these cases chemotherapy is not required, but is recommended since many of these cats will develop lymphoma at a.  In many cases  it is a manifestation of  multicentric  lymphoma, therefore all cats that are diagnosed with ocular lymphoma should be staged and have complete blood work, chest radiographs and an abdominal ultrasound