There was, however, a significant difference in TCII and TCII-R staining values between feline vaccine-associated fibrosarcomas and both canine soft tissue sarcomas (TCII: p<0.0073; TCII-R: p<0.0054) and feline soft tissue sarcomas and (TCII: p< 0.0134; TCII-R: p<0.0098), with higher staining values observed for feline vaccine-associated fibrosarcomas in both species; staining values for Ki-67 were significantly higher in feline vaccine-associated fibrosarcomas compared to canine soft tissue sarcomas (p<0.0352), but not compared to feline soft tissue sarcomas. The gene discussed is MKI67; the disease is fibrosarcoma.