Wound Healing
The veterinary oncologic patient has several risk factors that may increase the frequency of complications associated with wound healing (Cornell and Waters 1995). Nutritional compromise and concomitant disease can be treated to improve the outcome of wound healing, but other factors like tumor type and completeness of surgical excision have to be considered as well. Neoadjuvant/adjuvant therapies such as chemotherapy, radiotherapy, and antiangiogenic medications have also been documented to impair wound healing (Devereux et al. 1979; Cornell and Waters 1995; te Velde et al. 2002; Séguin et al. 2005) (see Chapter 2).
Proper surgical techniques, as described above, can be employed to decrease the chance of wound complications. Regular communication with the patient’s agent both before and after surgery will help to preemptively prepare for complications or aid in rapid identification and intervention when complications arise. Prevention of self‐trauma should be routinely discussed with the owner and methods of prevention such as bandaging or having the patient wear an Elizabethan collar should be included in the postoperative care.
Adjuvant Therapy
The time to discuss the potential need for adjuvant therapy in a tumor patient is prior to any surgical intervention. This allows owners to make informed choices and to better prepare for the financial burden, time required, and potential complications associated with adjuvant therapy. Failing to properly prepare the client for these additional treatments and the benefits and challenges unique to each one may leave the patient’s agent feeling overwhelmed, underinformed and may expose the patient to unnecessary morbidity or delay in treatment.
Chemotherapy in the adjuvant setting is generally administered after wound healing has been completed. Experimentally, it has been shown that administering certain types of chemotherapy before or at the same time as surgery may retard wound healing (Shamberger et al. 1981; de Roy van Zuidewijn et al. 1986; Lawrence et al. 1986a, b) (see also Chapter 2). By the time a patient is ready for suture/staple removal, a wound is generally healed sufficiently, and chemotherapy may be administered. The results of the biopsy will also be accessible at a similar time, and these can help to guide chemotherapeutic recommendations.
Radiation therapy may be administered preoperatively or postoperatively. In general, radiation therapy will slow wound healing. In cases where radiation is given either before or after surgery, it is important to ensure that there is minimal tension on the wound closure. This requires careful planning prior to and during the initial surgery. In some cases, if local flaps will require extensive dissection in areas away from the tumor bed and outside the proposed radiation field, it may be better to delay primary closure until it is known if tumor margins are clean. This will help prevent the seeding of tumor cells along the dissection planes where the flap will be raised. In postoperative patients who require radiation therapy but have wound complications such as infection or dehiscence, it is often better to try to manage the wound complication before beginning radiation. This may not always be possible as tumor remaining in the wound may prevent wound healing. In these cases, it may be necessary to go forward with radiation in an open wound setting. In many cases, once acute effects have resolved, the wound can be closed. In these cases, strict adherence to the “no skin tension” rule is imperative.
While certain basic concepts of surgery will remain static for the treatment of neoplasia, pursuit of better options for our patients will require that the surgical oncologist remains adaptive. It is hopeful that the desire for improved outcomes will continue to improve the lives of our patients as well as their agents. Prolonging a quality of life for veterinary patients and advising their agents appropriately about the options that we have to offer should remain our goal as advances in therapy occur.
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22 Engellau