Perioperative management - Partial gastrectomy with Roux-en-Y gastrojejunostomy

The tutorial demonstrates partial gastric resection in cancer of the distal third of the stomach.

Total gastrectomy, which had long been considered the procedure of choice in gastric cancer, does not offer any benefit over R0 resection by partial gastric resection.

When defining the extent of resection, the location of the tumor will be of overriding importance.

• Cancer in the distal third of the stomach → partial (four-fifths) resection
• Cancer in the middle third → gastrectomy
• Cancer in the proximal third with cardiac involvement → extended gastrectomy with transhiatal segmental resection of the distal esophagus

Other indications for total gastrectomy:

• Linitis plastica, a special variant of gastric cancer resulting in diffuse invasion of the gastric wall (mostly signet ring cell carcinoma)
• Cancer affecting several anatomical regions of the stomach (proximal, middle and distal third)

Defining the resection limits has to take into account not only the tumor site but also the histomorphological Laurén classification of gastric cancer:

• Diffuse type of cancer: Proximal margin 5 – 8 cm in situ, i.e., on fresh specimen without traction more than 5 cm
• Intestinal type of cancer: Proximal margin 4 – 5 cm, i.e., 2 – 3 cm on fresh specimen

Thus, in diffuse type of cancer in the distal third of the stomach and in the intestinal type in the middle and distal third of the stomach, partial distal resection usually suffices, while gastrectomy is indicated in all other cases.

Endoscopic resection of early gastric cancer

Superficial early cancer limited to the gastric mucosa (T1aN0M0) can be resected endoscopically because the risk of lymphatic spread is 0 – 2 %. If, on the other hand, the superficial region of the submucosa has already been invaded, the rate of lymph node metastasis jumps to 25 %.

According to the Japanese classification of gastric cancer, endoscopic submucosal resection may be performed in mucosal cancer, if:

• Lesion diameter < 2 cm, elevated type
• Lesion diameter < 1 cm, flat type
• No ulceration
• Histology: Well to moderately differentiated (G1-G2)

The aim is the en-bloc-R0-resection respecting the margins required by the histology of the tumor (intestinal type: 4 – 5 cm, diffuse type: 5 – 8 cm). Patients with helicobacter pylori colonization should be eradicated first.

Significant comorbidity with patient unfit for anesthesia and/or surgery

Palliation

For symptomatic stenosis, bleeding and metastasis of the tumor, the current German S3 guideline on gastric cancer surgery offers these consensus statements based on published trials:

Tumor stenosis

• Stenting, gastroenterostomy, jejunal feeding tube or palliative radiotherapy
• Palliative resection: Only in exceptional cases, since there is insufficient evidence

Tumor bleeding

• Endoscopic hemostasis; if not possible or ineffective:
• Angiographic embolization
• Palliative resection as a measure of last resort
• Chronic seepage: Palliative radiotherapy

Metastases

Regarding survival, there is insufficient evidence at present for the effectiveness of surgery in metastatic spread. In individual cases, resection of isolated organ metastases (liver, ovaries) may be considered in the absence of peritoneal spread.

Mandatory:

• Esophagogastroduodenoscopy with biopsies
• In patients considered for curative management, primary tumor staging should include endosonography
• Abdominal ultrasound to rule out metastases
• Thoracic/abdominal CT scans for M staging

Optional:

• Tumor markers (CA 72-4, CA 19-9, CEA)
• Abdominal MRI (magnetic resonance imaging) should be reserved for those patients unable to undergo CT scanning
• Possibly peritoneal lavage with cytology to complement staging
• Laparoscopy in locally advanced tumors (T3/4) to rule out extensive peritoneal spread or M staging, possibly incorporating IOUS (intraoperative ultrasound) and exploratory biopsy

• In patients with significant weight loss before surgery, preoperative nutrition therapy may be initiated, if needed.
• Special laxative measures are not required. As required by the anesthetists, the patient should have nothing by mouth before surgery (for at least 2 – 6 hours).
• Blood grouping; packed RBCs on call

General risks

• Thromboembolism
• Pneumonia
• Heparin intolerance, HIT
• Urinary tract infection

Special surgical risks:

• Final decision on the type of resection only during the procedure
• Injury of internal vessels and organs, e.g., spleen, bile duct
• Anastomotic failure
• Duodenal stump failure
• Endoluminal/ intraabdominal bleeding
• Intraabdominal abscess, peritonitis
• Pancreatitis and pancreatic fistulas
• Secondary healing
• Incisional hernia

Possible extension of the procedure:

• Cholecystectomy
• Resection of liver metastases
• Splenectomy (Note: If during planned partial gastrectomy splenectomy is indicated, e.g., injury to the spleen usually requires total gastrectomy!)

Information on:

• Temporary weight loss
• Changes in eating habits
• Drains, nasogastric tube, urinary catheter
• Possibly allogeneic blood transfusions