Читать книгу Veterinary Surgical Oncology - Группа авторов - Страница 54

In certain scenarios, cutaneous or mucosal flaps are needed to close the defect left after surgical removal of large or anatomically challenging tumors. Depending on the type of flap or graft utilized, the advanced, transposed, or grafted tissue may have a limited or more restricted blood supply (Seguin et al. 2005). Furthermore, in some cases where a flap or graft is employed, tumor excision may still be microscopically incomplete and thus adjuvant radiation therapy is indicated. Unfortunately, post‐operative radiation therapy can negatively impact wound healing and lead to flap failure. Given the known negative effects of radiation on the vasculature, Guo et al. (2012) evaluated the impact of pre‐operative fractionated radiotherapy on aortic grafts in a dog model and showed suppression of neointima migration and growth within the grafts after explant (Guo et al. 2012). In a study of 29 dogs undergoing a combination of radiation therapy and cutaneous or mucosal flapping procedure, 20/26 (77%) had some sort of complication, including dehiscence, flap necrosis, infection, and ulceration. The risk of complications was not higher when radiation was performed before surgery when a graft was not used to treat a radiation complication but the severity was greater. However, the use of a flap to treat damaged tissue secondary to radiation was more likely to result in a complication. Higher dose per fraction (4 Gy versus 3 Gy) was significantly associated with an increased severity of complications (Seguin et al. 2005). Similar to humans, radiation to the head and neck location, other than the oral location, was significantly associated with a decreased severity of complications. A modest population (15%) of dogs had an unresolved complication, therefore, despite a significant number of complications, 85% of dogs received a successful combination of radiotherapy and surgery (Seguin et al. 2005).