Читать книгу Veterinary Surgical Oncology - Группа авторов - Страница 53

In humans, the timing of surgery and radiation impacts tissue healing and overall outcome. Compared to post‐operative radiation, whose field must not only include the wound bed but also a margin of normal tissue surrounding it, pre‐operative radiation requires a lower dose of radiation to a smaller volume of tissue, thus resulting in fewer late complications and improved functional outcomes. However, pre‐operative radiation is associated with higher rates of acute and late wound healing complications (Griffin et al. 2015). A few studies in human patients and animal models have evaluated the impact of surgical timing following irradiation of the tumor bed. Specifically, pre‐operative radiation has been associated with a higher chance of wound healing complications than post‐operative radiation in patients with extremity soft tissue sarcomas (O'Sullivan et al. 2002), a lower chance of successful outcome compared to patients receiving post‐operative radiation (Wang et al. 2003) for head and neck cancers, and higher morbidity compared to patients not receiving radiation (Halle et al. 2009)for head and neck cancers. O'Sullivan et al. (2003) showed that in general, pre‐operative radiation for head and neck sarcomas is associated with lower rates of major wound complications compared to that for extremity sarcomas (O'Sullivan et al. 2003). As far as specific timing of pre‐operative radiotherapy relative to surgery, Halle et al. (2009) showed that the largest increase in all complication rates was seen when more than six weeks elapsed between the last radiotherapy session and surgery (Halle et al. 2009). Another study by Griffin et al. (2015) showed a statistically insignificant trend toward a higher rate of wound complications for patients who had surgery to remove distal extremity soft tissue sarcomas greater than six weeks after radiation therapy but no difference among the groups of patients that underwent surgery three, four, or five weeks following radiation therapy (Griffin et al. 2015). As for the timing of surgery relative to the radiation, when radiation is done in the neoadjuvant setting, surgery is performed once the skin’s acute side effects are resolved.