Laparoscopic-Assisted Colon Surgery

Article Outline

• ABSTRACT
• Minimally Invasive Colorectal Surgery
  • Disadvantages
  • Contraindications
• Preoperative Evaluation and Candidate Selection
• Intraoperative Patient Care
  • Sigmoid colectomy
  • Right hemicolectomy
• Postoperative Patient Care
• Follow-up Care
• Case Study
• Advances in Laparoscopic Colon Resection
• Examination
  • Laparoscopic-Assisted Colon Surgery
    • Purpose/Goal
    • Behavioral Objectives
    • Questions
• Answer Sheet
  • Laparoscopic-Assisted Colon Surgery
• Learner Evaluation
  • Laparoscopic-Assisted Colon Surgery
    • Purpose/Goal
    • Objectives
    • Content
    • Test Questions/Answers
    • Learner Input
• References
• Copyright

ABSTRACT 

LAPAROSCOPIC-ASSISTED colon surgery is a safe alternative to conventional open colectomy. Using the laparoscopic approach, the surgeon uses tools through port sites to mobilize the section of colon to be removed, avoiding a large laparotomy incision. Usually, two to three 5-mm port sites and one 10-mm or 12-mm port site are created.

ALTHOUGH THIS PROCEDURE often requires a small incision to remove the diseased portion of the colon, the incision is much smaller, causing less postoperative pain and shortening the hospital stay. This leads to a faster return to activities of daily living for the patient. AORN J 88 (September 2008) 403–412. © AORN, Inc, 2008.

The first laparoscopic surgery was performed in 1901 by George Kelling, MD.¹ Dr Kelling was able to view the peritoneal cavity of a dog using two trocars, one to insufflate the abdomen with filtered air and the other to insert a cystoscope. The first laparoscopic procedure performed on a human occurred in 1910. The surgical procedure was performed by Hans Christian Jacobaeus, MD, to investigate ascites.¹ The surgeon performed the procedure using a single trocar site. The camera had a light at the distal end and also allowed air passage for insufflation. The light at the distal end of the camera, however, posed a thermal injury complication in early laparoscopy. Other complications in early laparoscopy included bowel and vascular injuries.¹

Numerous advances have been made since the early days of laparoscopy (Figure 1). Since 1994, laparoscopic procedures have been improved using similar techniques and newer versions of the same devices. Laparoscopy, with smaller incisions and a shorter recovery time, has revolutionized abdominal surgery. Although most often performed on patients with benign disease, laparoscopy is now accepted more readily for patients with malignant disease as well.

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• Figure 1. 

  Timeline of Laparoscopic Surgery from 1911 through 1994^1,2

Some advantages of laparoscopic versus open procedures include

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Minimally Invasive Colorectal Surgery 

Some recent studies show laparoscopic colectomy outcomes to be better than those for open sigmoid colectomy for the treatment of benign and malignant disease because of the advantages of laparoscopic techniques.³, ⁴ A variety of conditions can be treated by laparoscopic colectomy, including

An advantage of the laparoscopic approach to colectomy is that colon function normalizes faster after laparoscopic manipulation than after open exposure manipulation. Since the laparoscopic approach causes less intra-abdominal scarring and adhesion formation, the laparoscopic approach often is preferred, particularly because it may reduce the incidence of obstructive episodes.²

Disadvantages 

A major disadvantage of the laparoscopic approach for colectomy is an increase in OR time. One study suggested a mean operating time increase of 55 minutes for laparoscopic colectomy versus open colectomy.⁴ This time may decrease as surgeons become more experienced and perform increased numbers of laparoscopic procedures. Laparoscopic colectomy (ie, right or sigmoid) is a technically difficult procedure that requires a steep learning curve for all involved health care providers.⁵ Cost also is a disadvantage as a result of increased OR time and increased cost of instrumentation (eg, trocars, cannulas, staplers, fiberoptic light sources).

Contraindications 

There is no indication at this time that the laparoscopic approach is associated with worse long-term outcomes than an open procedure; therefore, there are very few true contraindications. Some conditions make the laparoscopic approach more difficult, such as

The laparoscopic approach may be contraindicated for patients suffering from severe restrictive pulmonary disease, which makes it difficult for the anesthesia care provider to provide adequate ventilatory support and decreases the patient's ability to tolerate the carbon dioxide (CO₂) insufflation necessary to achieve a pneumoperitoneum. The size of the lesion also may make the laparoscopic approach inappropriate because of the size of the incision necessary to remove the tumor from the abdomen.⁶

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Preoperative Evaluation and Candidate Selection 

Preoperative evaluation should focus on issues that

The presence of a synchronous colonic neoplasia would exclude laparoscopic colectomy as a treatment option and, therefore, should be identified preoperatively by colonoscopy or air-contrast barium enema in combination with sigmoidoscopy.

A preoperative carcinoembryonic antigen (CEA) level provides useful prognostic information because CEA is elevated in the serum of individuals with colorectal, gastric, pancreatic, lung, and breast cancer. If the CEA level does not decrease after surgical removal of the tumor, this is an indication of tumor reoccurrence. Serum CEA levels also are increased in conditions such as ulcerative colitis, pancreatitis, and cirrhosis.

Abdominal computed tomography (CT) or hepatic ultrasonography should be performed in patients with hepatomegaly or abnormal liver function tests. If preoperative radiation therapy is planned, abdominal CT is appropriate to exclude extrapelvic disease that would preclude preoperative radiation. The benefit of routine preoperative CT in patients with otherwise resectable colonic or rectal cancer remains unclear.⁵

Patients with rectal cancer should undergo a careful digital palpation performed by an experienced physician combined with rigid proctosigmoidoscopy. Intrarectal ultrasonography may provide more objective data with regard to the extent of the local disease.

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Intraoperative Patient Care 

After the patient arrives at the preoperative holding area, the preoperative nurse prepares the patient for surgery and organizes the patient's medical records. The circulating nurse and RN first assistant (RNFA) evaluate the patient's chart for completeness, including current history and physical examination, laboratory values, and the surgical informed consent. After the circulating nurse introduces himself or herself to the patient and family members, the nurse confirms the surgical procedure, as well as the patient's NPO status, allergies, and current medications. The circulating nurse ensures that the preoperative antibiotic was administered as ordered by the surgeon and that the patient has on thromboembolic disease hose. The circulating nurse then develops a nursing care plan specific to the patient undergoing laparoscopic colon surgery (Table 1).

Table 1. Nursing Care Plan for Patients Undergoing Surgery for Laparoscopic Colon Surgery

Patients undergoing open-cavity surgery have an increased risk of “substantial heat loss into the relatively cool environment of the OR.”^7(p409) According to AORN's “Recommended practices for the prevention of unplanned perioperative hypothermia,” patients at risk of unplanned hypothermia should be prewarmed for a minimum of 15 minutes immediately before induction of anesthesia to minimize the effect of anesthesia-induced vasodilation.⁷ Therefore, the circulating nurse ensures that the patient is warmed with a forced-air warming blanket device for a minimum of 15 minutes in the preoperative holding area.

The circulating nurse and anesthesia care provider transport the patient on a stretcher to the OR and help the patient move onto the OR bed in a supine position. After placing an upper body temperature-regulating blanket on the patient, the circulating nurse applies sequential compression device leggings and ensures that they are initiated before induction of anesthesia. The circulating nurse then secures the safety strap across the patient's thighs.

At this point, the circulating nurse performs the surgical time out with all surgical team members and the patient. The time out includes stating

verifying all information with the patient, his or her completed informed consent, and the identification bracelet. After induction of general anesthesia and endotracheal intubation, the anesthesia care provider inserts an orogastric tube at the surgeon's discretion.

Sigmoid colectomy 

For a sigmoid colectomy, the surgeon, circulating nurse, and RNFA place the patient in low lithotomy position using padded stirrups. Extending the patient's arms on padded arm boards is the preferred method but if this is not possible, the circulating nurse ensures that both of the patient's arms are padded and tucked at the patient's side. The circulating nurse checks for proper body alignment and ensures that all pressure points are padded.

While the surgeon and RNFA perform surgical hand scrubs, the circulating nurse performs the surgical skin prep for a cystoscopy and placement of a left ureteral catheter that will facilitate identification of the left ureter intraoperatively. The nurse then performs two separate preps—one of the patient's perineum and a second of the entire abdomen with an antimicrobial solution. The circulating nurse also inserts an indwelling urinary catheter. After the circulating nurse places the electrosurgical unit (ESU) dispersive pad on the patient's lateral thigh, the scrub person and RNFA assist the surgeon in draping the patient and preparing the sterile field, including securing the CO₂ tubing, light cord, camera cord, ESU hand piece, suction irrigator, suction tubing, and ultrasonic scalpel.

Under direct vision, the surgeon inserts a specially designed trocar and port that can accommodate a 5-mm scope in the patient's right upper mid-abdomen (Figure 2). The surgeon then achieves the pneumoperitoneum by insufflating the patient's abdomen with CO₂ gas. This pushes the abdominal wall away from the intestines, allowing the surgeon room to work laparoscopically with specially designed instruments and a video camera.¹ During the entire procedure, the intraperitoneal pressure is maintained at 10 mm Hg to 12 mm Hg. The anesthesia care provider changes the OR bed position during the procedure as an additional measure as needed to facilitate retraction of the small bowel from the surgical field.⁸

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• Figure 2. 

  Port A, in the supraumbilical area, is used for a 5-mm scope; port B, in the suprapubic area, is used for a 5-mm scope; port C, in the right upper quadrant, is used for direct visualization with a 5-mm or 10-mm scope; port D, in the right lower quadrant, is used for the staples.

The surgeon places additional 5-mm trocars in the mid-epigastric area just above the patient's umbilicus and in the patient's suprapubic area. The surgeon also places a 10-mm or 12-mm trocar in the patient's right lower quadrant. The RNFA inserts the 10-mm, 30-degree laparoscope through the right lower quadrant port. Using atraumatic graspers through the 5-mm ports, the surgeon moves the small bowel to see the colon. The surgeon then mobilizes the portion of colon to be resected and devascularizes it using the ultrasonic scalpel intracorporeally and uses endoscopic vascular clips to ligate major vessels.²

To obtain adequate margins of normal colon proximal and distal to the diseased area, the surgeon frees the colon up to the splenic flexure.⁵ During this portion of the procedure, the RNFA moves the laparoscope, under the direction of the surgeon, to allow the surgeon to best see the area of dissection. The surgeon dissects the colon free distally until the rectum can be identified. Care is taken during this entire dissection to identify and protect the left ureter with the ureteral catheter in place.

After mobilization of the colon, the RNFA removes the 10-mm laparoscope and uses a 5-mm laparoscope through the right upper quadrant or epigastric port for the stapling portion of the procedure. The surgeon uses a contour stapler to transect the colon at the rectum and clamps an atraumatic grasper to the sigmoid end of the transected colon.

The surgeon makes a transverse incision in the suprapubic area, extending the 5-mm trocar site, and the RNFA places retractors at the skin edge to provide a better view. The surgeon transects the rectus fascia transversely and incises the posterior fascia vertically. The surgeon and RNFA place a wound protector to wall off the incisional edges.

Using the attached atraumatic grasper and a Babcock clamp, the surgeon delivers the distal end of the transected colon through the incision. The surgeon clamps the proximal end with a rubber shod clamp and clamps the diseased end to be removed with a Kocher clamp. The surgeon then transects the diseased portion of colon with a #10 knife blade and removes the transected portion.

The surgeon places a 2-0 polypropylene purse-string suture in the end of the colon. He or she inserts the anvil of the circular anastomosis stapler into the colon and secures the purse string. After returning the colon to the abdomen, the RNFA twists the wound protector to close off the incision so the abdomen can be reinsufflated.

The RNFA moves to the rectal surgical field and irrigates the rectum with a diluted povidone-iodine solution (ie, 900 mL normal saline with 100 mL povidone iodine). He or she then digitally dilates the rectum and places the circular stapler into the rectum. Under the guidance of the surgeon, the RNFA advances the stapler to the distal rectal stump, and then advances the spike anterior to the staple line until the orange guide marker is visible. The surgeon pushes the anvil onto the spike until it clicks into place.

After checking to ensure that the colon is not twisted and is in good alignment, the RNFA closes the stapler. Under the surgeon's guidance, the RNFA checks the stapler to make sure it is properly closed before firing. The RNFA then fires the stapler, opens the stapler, and removes it from the rectum.

The RNFA checks the tissue in the stapler to ensure that the proximal and distal pieces of donut-shaped tissue are completely present. The surgeon instills fluid into the patient's abdomen. The RNFA then inserts the rigid sigmoidoscope and instills air into the patient's rectum. Absence of air bubbles in the peritoneal cavity indicates that there are no leaks at the anastomosis site.

The surgeon irrigates the patient's abdominal cavity and removes all trocars under direct vision. The RNFA assists the surgeon with fascial closure of the Pfannenstiel incision and the 10-mm or 12-mm trocar site; then the RNFA closes the skin of the incision and all of the trocar sites. At the beginning of wound closure, the circulating nurse and scrub person perform a sponge, needle, and instrument count. They count the sponges and needles again at skin closure. The scrub person and RNFA clean the surgical site and apply sterile dressings. The RNFA then removes the ureteral catheter.

Right hemicolectomy 

For a right hemicolectomy, the patient is placed in the supine position. A ureteral catheter is not inserted. The OR bed is placed in the Trendelenburg position with the bed rotated so the patient's right side is upward. After adequate mobilization of the diseased right colon, the surgeon makes a small incision over the area of the abdomen that will provide the best access to deliver the segment of resected colon. The surgeon performs the resection and anastomosis of the diseased segment extracorporeally either with staples or with sutures.⁵ After resection, the surgeon returns the anastomosed colon to the abdominal cavity.

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Postoperative Patient Care 

After the circulating nurse and RNFA return the patient to the supine position, the circulating nurse removes the ESU dispersive pad and checks the site for burns or skin irritation. The circulating nurse applies warm blankets for patient comfort and then helps the anesthesia care provider and RNFA transfer the patient to the postanesthesia care unit (PACU) bed, maintaining the patient's proper body alignment throughout the process. In the PACU, the circulating nurse provides the RN-to-RN transfer paper to the PACU nurse and gives a verbal transfer report.

The PACU nurse monitors the patient's vital signs and level of pain and provides pain management as needed. The RNFA writes postoperative orders to be checked and countersigned by the surgeon. When the patient is stable, the PACU nurse transfers the patient to the medical-surgical patient care unit.

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Follow-up Care 

Approximately 148,000 new cases of colon and rectal cancer are diagnosed in the United States annually.⁹ Of these cases, approximately 75% of patients will have had the disease entirely removed during an initial surgical procedure; therefore, approximately 110,000 patients per year should receive follow-up care from their primary health care provider or oncologist.⁹ Although follow-up care improves survival, ensures better outcome monitoring, identifies other treatable diseases earlier, and ensures provision of better emotional and psychological support,⁹ it also may increase physical, financial, and psychological stress.⁹

The Standards Practice Task Force and the American Society of Colon and Rectal Surgeons jointly wrote practice parameters for follow-up care.⁹ These practice parameters include the following:

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Case Study 

Ms K, a 54-year-old woman, was diagnosed with multiple diverticula after a routine screening colonoscopy at age 50. At that time, she had no symptoms and did not change her diet. Until recently, she had not had any problems. One month ago, Ms K experienced left lower quadrant pain and a fever and complained of a “twisting sensation.” Her primary care physician diagnosed acute diverticulitis and admitted Ms K to the medical-surgical unit for further treatment. A CT scan of her abdomen indicated recurring diverticulitis, and the patient was treated with ciprofloxacin and metronidazole. In three days, the patient was discharged and instructed to eat a high-fiber diet.

Two weeks later, Ms K began feeling ill with recurrence of left lower quadrant pain and a fever, as well as left back pain radiating to her sacroiliac area. Her primary care physician ordered a repeat CT scan that identified diverticulitis and gallstones. Ms K was referred to a general surgeon who recommended that she undergo a laparoscopic sigmoid colectomy as well as a laparoscopic cholecystectomy and laparoscopic appendectomy.

The patient is admitted for surgery with a diagnosis of recurring diverticulitis, cholecystitis, and potential for appendicitis. After induction of general anesthesia, the circulating nurse, RNFA, and anesthesia care provider place the patient in the low lithotomy position. After the circulating nurse performs the skin prep, the surgeon performs a cystoscopy and inserts a left ureteral catheter and an indwelling urinary catheter.

After the circulating nurse applies the ESU grounding pad, the scrub person and RNFA drape the patient and prepare the sterile field. Under direct vision, the surgeon then places a specially designed 5-mm trocar and port in the patient's right upper abdomen and insufflates the patient's abdomen to a pressure of 12 mm Hg. The surgeon then places two additional 5-mm ports to the left and right of the patient's umbilicus for the cholecystectomy. The surgeon transects the omentum of the gallbladder using the ultrasonic scalpel and bluntly dissects to clearly identify the cystic duct and the cystic artery. The surgeon uses endoscopic clips, two proximally and one distally, to secure the cystic duct and then secures the cystic artery in the same manner. After severing both the cystic duct and cystic artery, the surgeon dissects the gallbladder free from the liver bed using a hook ESU device. The surgeon placed the gallbladder in a retrieval bag but leaves it in the abdomen during the remainder of the dissection.

At this time, the surgeon places a 12-mm port in the right lower quadrant and an additional 5-mm port in the suprapubic area under direct visualization. Using a 10-mm, 30-degree laparoscope, the surgeon dissects the sigmoid colon. He then uses the ultrasonic scalpel to incise the mesentery and dissect adhesions. The surgeon makes a window in the mesentery of the sigmoid colon with the ultrasonic scalpel and frees the sigmoid colon up to the splenic flexure using the same technique. The surgeon performs further dissection with the ultrasonic scalpel to completely free the transverse colon. When the colon has good mobility, the surgeon transects it at the pelvic rim using two firings of the endoscopic stapler.

After performing the colectomy as described earlier and checking the anastomosis for leaks, the surgeon makes a window in the mesoappendix and uses a standard 45-mm stapler to transect the appendix flush with the cecum. The surgeon then transects the mesoappendix with a vascular stapler and uses endoscopic clips and the ESU for hemostasis. The surgeon places the appendix in a retrieval bag and removes it through the 12-mm trocar site, after which he removes the gallbladder through the same site.

To close the right lower quadrant trocar site, the RNFA uses a 0-polyglactin suture in a figure-8 fashion and then removes all trocars under direct vision. The RNFA reapproximates all wound edges using 4-0 poliglecaprone. The RNFA and scrub person apply one-quarter inch self-adhesive skin approximating strips over which they apply nonadherent dressing pads to dress the wounds. After the RNFA removes the ureteral catheter, the circulating nurse and RNFA remove the patient's legs from the stirrups and place Ms K back into the supine position.

After extubating the patient, the circulating nurse and RNFA help the anesthesia care provider move Ms K to the bed, maintaining her body alignment, and then transfer her to the PACU. Postoperatively, the patient receives IV morphine sulfate for pain.

In the nursing unit, nurses encourage Ms K to use her incentive spirometer to minimize postoperative respiratory complications. Initially, Ms K is able to tolerate ice chips and on postoperative day one, she is started on clear liquids. The nurse notes that bowel sounds are present but diminished, and the patient has some red discharge from the rectum, which is expected after this surgery. Ms K also starts ambulating on postoperative day one.

On postoperative day two, Ms K is afebrile and the indwelling urinary catheter is removed. She continues to have some red discharge from her rectum. The nurses manages Ms K's pain with oral acetaminophen and hydrocodone.

By postoperative day three, Ms K is tolerating full liquids and passing flatus. The nurses discharge Ms K, instructing her to advance her diet as tolerated and follow up with her surgeon in 10 days. In an interview two months after surgery, Ms K states she was able to discontinue all pain medication one week after surgery and is not having any problems.

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Advances in Laparoscopic Colon Resection 

Great advances have been made in laparoscopic surgery during the past 20 years, from diagnostic procedures to colon resections. A variety of diseases have been treated successfully using the laparoscopic approach, including malignant diseases. The advantages of the minimally invasive approach make it the treatment of choice for patients requiring a colectomy. The laparoscopic technique has a shortened recovery time, allowing the patient to return to normal activities sooner. This approach may be a better option than open colectomy for select high-risk patients, such as those who are elderly or obese.

Laparoscopic colectomy presents new challenges for perioperative nurses and RNFAs. Patients who may meet the criteria for this procedure range from the young to the elderly, from the actively ill to patients with chronic conditions. Perioperative nurses must be prepared to care for members of the diverse population that may undergo these procedures.

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Examination 

Laparoscopic-Assisted Colon Surgery 

Purpose/Goal 

To educate perioperative nurses about caring for patients undergoing laparoscopic-assisted colon surgery.

Behavioral Objectives 

After reading and studying the article on laparoscopic-assisted colon surgery, nurses will be able to

Questions 

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Answer Sheet 

Laparoscopic-Assisted Colon Surgery 

Event #08049

Session #1313

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Learner Evaluation 

Laparoscopic-Assisted Colon Surgery 

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This evaluation is used to determine the extent to which this continuing education program met your learning needs. Rate these items on a scale of 1 to 5.

Purpose/Goal 

To educate perioperative nurses about caring for patients undergoing laparoscopic-assisted colon surgery.

Objectives 

To what extent were the following objectives of this continuing education program achieved?

Content 

To what extent

Test Questions/Answers 

To what extent

Learner Input 

What other topics would you like to see addressed in a future continuing education article? Would you be interested or do you know someone who would be interested in writing an article on this topic?

Topic(s):______________________________________________________________________________________________________________________

Author names and addresses:___________________________________________________________________________________________________

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References 

1. Mishra RK . History of minimal access surgery . http://www.laparoscopyhospital.com/history_of_laparoscopy.htm Accessed June 9, 2008.
   • View In Article
2. Ahad S , Figueredo EJ . Laparoscopic colectomy . MedGenMed . 2007;9(2):37
   • View In Article
   • MEDLINE
3. Noel JK , Fahrbach K , Estok R , et al.   Minimally invasive colorectal resection outcomes: short-term comparison with open procedures . J Am Coll Surg . 2007;204(2):291–307
   • View In Article
   • Full Text
   • Full-Text PDF (172 KB)
   • CrossRef
4. Kahnamoui K , Cadeddu M , Farrokhyar F , Anvari M . Laparoscopic surgery for colon cancer: a systematic review . Can J Surg . 2007;50(1):48–57
   • View In Article
   • MEDLINE
5. Tilney HS , Lovegrove RE , Purkayastha S , Heriot AG , Darzi AW , Tekkis PP . Laparoscopic vs open subtotal colectomy for benign and malignant disease . Colorectal Dis . 2006;8(5):441–450
   • View In Article
   • MEDLINE
6. Ballantyne GH . Laparoscopic colectomy: an update . http://lapsurgery.com/Lif_cole.htm Accessed June 9, 2008.
   • View In Article
7. Recommended practices for the prevention of unplanned perioperative hypothermia . In: Perioperative Standards and Recommended Practices . Denver, CO: AORN, Inc; 2008;p. 407–420
   • View In Article
8. Sgambati SA . Minimally invasive surgery for diseases of the colon & rectum: the legacy of an ancient tradition . In:  Jager RM ,  Wexner S editor. Laparoscopic Colorectal Surgery . New York, NY: Churchill & Livingstone; 1995;p. 13–23
   • View In Article
9. Anthony T , Simmang C , Hyman N , et al. , Standards Practice Task Force  , American Society of Colon and Rectal Surgeons    Practice parameters for the surveillance and follow-up of patients with colon and rectal cancer . Dis Colon Rectum . 2004;47(6):807–817
   • View In Article
   • MEDLINE
   • CrossRef