Oxford American handbook of oncology. Second Edition. Oxford University Press (2015)
Surgical palliation falls into several different categories, requiring a broad range of expertise and knowledge.
A patient’s life expectancy may vary from weeks to years, depending on their condition. The surgeon must know when not to operate and when to use palliative care teams and interventional radiology, as well as decide when and what operation is required.
Patients with colon or ovarian cancer make up the bulk of those developing small- or large-bowel obstruction. In a colon cancer patient, confirmation of incurability will usually be made at laparotomy, after a decision to treat a large-bowel obstruction. Where possible, these patients should have the primary cancer excised and intestinal continuity restored by primary anastomosis.
Management of the obstructed ovarian cancer patient is usually more difficult, because the key decision is often whether the patient should have the operation. A multidisciplinary team discussion of these difficult patients, in consultation with the patients and their families, is essential. In general, a combined approach involving a colorectal surgeon and a cancer gynecologist is best.
Many patients will have multiple obstruction sites, with small and large bowel studded with tumors on the serosal surface. Such patients are not suitable for surgical palliation. Others will have one or two site obstructions. They can benefit from debulking, resection, and anastomosis or bypass surgery.
To differentiate these categories of patient, the following features and methods can be used: history of crampy abdominal pain, clinical examination revealing a distended tympanitic abdomen (as opposed to an abdomen with multiple sites of palpable tumor and ascites), plain x-rays revealing many loops of distended bowel with air-fluid levels, and CT evidence of pelvic or other single-site tumor deposit.
Laparoscopy will sometimes be helpful in the obstructed patient who has not had previous abdominal surgery. With modern techniques, laparoscopic bypass can be carried out by suitably trained surgeons in selected patients. This requires great care in the obstructed patient.
Fistulas caused by pelvic tumors or post-radiotherapy include the following:
- Combination of above
Preoperative assessment to determine the exact type of fistula is important.
- Aproximal end sigmoid colostomy, which can usually be performed without a formal laparotomy, is the treatment of choice for most rectovaginal fistulas if definitive surgery is not possible.
- Patients with combined rectovaginal and vesicovaginal fistulas may need an end colostomy and ileal conduit.
- Acovered stent, delivered endoscopically or radiologically, should be considered for patients with a colovesical fistula.
- Patients with an enterovesical fistula will require laparotomy, resection of small bowel segment, and anastomosis.
- For low vaginal fistulas, coloanal sleeve procedures may be helpful. This should be done by an appropriate colorectal specialist.
Obstructive jaundice can be palliated surgically by choledochoenterostomy or cholecystenterostomy, although these procedures have been largely superseded by endoscopic and radiological placement of stents. Stents can become blocked, resulting in repeated cholangitis.
A trial has demonstrated a shorter overall hospital stay and decreased morbidity for surgical palliation of jaundice compared with endoscopic stenting and should be considered in medically fit patients.
Selected patients with inoperable hilar tumors will be best treated by segment III biliary enteric bypass. In those patients who require surgical bypass of obstructive jaundice, laparoscopic techniques have a role in selected patients by appropriately trained surgeons.
Peritoneal-venous (Leveen) shunts can be inserted to relieve ascites in selected cases. Careful preoperative assessment should be undertaken to ensure that ascites is not loculated and that the tumor is not mucinous; otherwise the shunt will become blocked. These are usually inserted using local anesthetic and sedation, with >50% of patients achieving good, long-term palliation. Postoperative coagulopathy may be a problem.
There are several options open to oncological surgeons to help patients with pain:
- Surgical debulking of large, slow-growing tumors (e.g., intra-abdominal, soft-tissue sarcomas in otherwise fit patients for whom expected morbidity of the procedure is low)
- Stabilization of pathological fractures and prophylactic pinning of bone metastases involving >50% of cortex
- Neurosurgical approaches for pain control, including cordotomy
- Thoracoscopic splanchnectomy for intractable pain secondary to pancreatic cancer
In general, with modern pain management and specialist pain clinics, the requirement for a surgical approach to the spinal cord or to peripheral nerves is now limited.
A wide array of endoscopic and radiological techniques is available to stop bleeding from benign and malignant causes in patients with incurable cancer, including injection sclerotherapy (benign ulceration), laser coagulation (neoplastic ulcers), and radiological embolization (should other methods fail). Surgery should be reserved for those with a life expectancy of three months or more, for whom other methods fail.
In some patients, extensive local disease may prevent removal of all disease by surgery, but partial resection is still appropriate. This applies particularly to ovarian cancer, for which subsequent chemotherapy can lead to good results, even in advanced disease.
Palliative resection of the primary tumor
Up to 10% of patients with breast cancer will present with metastatic disease; patients with visceral metastases have a poor prognosis, but patients with bone metastases have a median survival of over two years. Resection of the primary tumor to achieve locoregional control may improve patients’ quality of life, preventing fungation or uncontrolled axillary metastases.
Patients with colorectal cancer are staged before surgery to determine the most appropriate therapy. In those in whom unresectable liver metastases are identified, primary tumor resection should still be considered to minimize the risk of bleeding, perforation, or obstruction, which may subsequently occur.
Laparoscopic surgery has a definite role in the palliation of malignancy, e.g., for gastric outlet obstruction, intestinal obstruction, and biliary bypass for obstructive jaundice (pancreatic cancer). Feeding tubes for nutrition can also be placed laparoscopically, the colon and small bowel can be decompressed, and stomata can be created using minimally invasive techniques.