Iatrogenic

 The Greek term "iatros" means physician, and the suffix "genes" means produced. These terms are combined to form the word "Iatrogenic" which means physician induced. The term iatrogenic is listed as a pathophysiologic mechanism, or cause, of •some diseases. It emphasizes to us that there are some patients we cannot help, but there are none we cannot harm.

This point seems especially pertinent with the problem of injection site sarcomas in cats. The problem used to be called vaccination site sarcomas but it has now been shown that any irritating substance can initiate a sequence of inflammation, formation of a granuloma, activation of an oncogene (cancer causing gene), and the formation of a fibro sarcoma (cancer). The knowledge of this problem first came to light in a Letter to the Editor in the Journal of the American Veterinary Medical Association in 1991. Since then much information has been produced concerning the problem. Materials implicated in the cancers are: killed virus vaccines (rabies, leukemia, some feline distemper, most distemper vaccines are modified live virus's), Program Injectable Flea Medicine (the oral form is totally safe), surgical implants (pins, plates, screws, and wires). We expect that even the implanted microchips will be implicated. The reaction around the inert glass capsule is a chronic inflammation, which is the underlying cause of these cancers.

In October of 1998 we had a Letter to the Editor published in The Journal of the American Veterinary Medical Association. The letter was a report of two cases of vaccine-induced cancers. The notable point was documenting these tumors occurring seven and eleven years after the injection, was given. Prior to this there was nothing in the literature documenting these tumors longer than three years after the injection. Our cases demonstrate that there is effectively no outside limit on the occurrence of the cancers after the injection. -To date we have found 18 cats to have 19 first time occurrences of this cancer. The majority of these cats died from recurrence of the tumor. Our efforts to reduce this problem have been to stop vaccinating indoor cats for Leukemia and Rabies.  They have no exposure because they are protected from exposure by keeping them indoors. As we reduce the use of the vaccines we will reduce the incidence of the disease. Currently it is believed that 20,000 to 30,000 cats a year are dying from this problem. Quite a case of iatrogenic disease. Further information in another article.