Page 192 - Withrow and MacEwen's Small Animal Clinical Oncology, 6th Edition

CHAPTER 10 Surgical Oncology 171

susceptibility to certain cancers likely will increase the surgical surgery is beneficial in cats with mammary carcinomas. 17,88–90
indications for prevention. It is well known that early (<1 year) More surgery is not always better surgery. Long-term follow-up
of well-staged and graded tumors with defined surgical technique
oophorectomy reduces the risk of mammary cancer in the dog
VetBooks.ir by 200-fold compared with intact dogs (and to a lesser degree in and margins is necessary to demonstrate the true value of any
operation. A great deal of progress in surgical technique and surgi-
cats). Castration of the male dog helps prevent perianal adenomas
and, obviously, testicular cancer. Removal of in situ SCC (precan- cal thinking needs to take place before the use of surgery can be
cerous) from the skin of white cats or removal of in situ adenoma- optimized.
tous polyps from the rectum of dogs may also prevent malignant A better understanding of expected tumor biology and more
transformation of these tumors. Elective removal of cryptorchid precise staging methods (e.g., molecular diagnostics, angiograms,
testes, which are at high risk for tumor development, is another ultrasound, CT, MRI, positron emission tomography/CT) will
example of preventive surgery. facilitate more precise surgical operations. Surgical techniques will
continue to improve and undergo refinement, 75,91–93 but until
Miscellaneous Oncologic Surgery surgeons become biologists, the big breakthroughs will be slow in
coming. Surgeons should be investigating the influence of anes-
Veterinary surgeons are being called on increasingly to facilitate thesia, infection, immune function, blood transfusions, growth
the medical management of cancer patients. The placement of factors, oncogenes, and cytokines, to name a few factors, on the
long-term vascular access catheters for delivery of fluids, che- outcome of our patients. 94–100
motherapy, or anesthetic and analgesic agents has become com- In spite of these anticipated advances in technology and biol-
monplace, and ports are routinely placed to aid in the evacuation ogy, the most difficult aspect to learn is surgical judgment. As
of malignant thoracic effusions (e.g., mesothelioma). Operative Cady has said, “Biology is king; selection of cases is queen; and
placement of various enteral and parenteral feeding tubes also is the technical details of surgical procedures are the princes and
common. princesses of the realm, who frequently try to overthrow the pow-
Surgeons and radiation oncologists may work together to treat erful forces of the king or queen, usually to no long-term avail,
large cancers or tumor beds after excision with intraoperative RT. although with some temporary apparent victories.” 101
Surgical intervention for oncologic emergencies is not infrequent;
such emergencies include intractable pain, bleeding, pathologic References
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