In the past gastrectomy was mostly used as a treatment for stomach ulcers, however now this procedure is used primarily for cancer of the stomach. Every year in the United States about 25,000 people develop gastric (stomach) cancer. Stomach cancer is more common in Asia and South America. While great strides have occurred in curing this disease much depends on where in the stomach the cancer begins and whether the cancer is found before is spreads outside the stomach.

Anatomy and Physiology

• The stomach is a C-shaped organ that is part of the digestive system and lies under the left lower ribs and left upper part of the abdomen (Figure 1)

Figure 1 - Anatomy of the stomach. The cardia is the upper part of the stomach near the esophagus. The pylorus is at the end of the stomach. Note the relationships of the liver, spleen, pancreas, gallbladder, duodenum and jejunum to the stomach. © N.Gordon

• Preparation for anesthesia
  1. Food entering the mouth is passed into the esophagus and then goes into the upper end of the stomach. The stomach holds and mixes the food with gastric juices that aid in digestion and then passes the mixture through the pylorus, a muscular sphincter or gate, that controls the passage of the stomach contents into the duodenum, which is the beginning of the small bowel
  2. The gastric juices are produced by glands in the wall of the stomach. After three to four hours, food entering the stomach is reduced by these juices to a liquid and ready to enter the small bowel to continue digestion
  3. The stomach is divided into three parts:
     1. The cardia is the part of the stomach that is adjacent to the esophagus
     2. The body of the stomach is the largest part and has two curvatures, the lesser curvature, which lies on the inside of the C, and the greater curvature, which lies on the outside of the C
     3. The pylorus is the part of the stomach that lies at the end of the stomach and is demarcated from the body by a difference in the type of glands from those in the body
  4. The wall of the stomach is divided into four layers
     1. The mucosa is the inner layer and contains the glands that produce the gastric juice
     2. The submucosa is a thin layer lying just beneath the mucosa
     3. The muscularis is the muscle layer that has an inner circular portion and an outer layer that runs the length of the stomach
     4. The serosa is the outer layer of the stomach

The stomach is mobile and changes shape depending on whether it is full or empty or whether the person is standing or lying down. It is relatively fixed at the cardia, the part of the stomach near the esophagus

Pathology

• Some factors that may predispose (lead) to gastric cancer are
  1. Smoking
  2. High salt diet
  3. Infection with the bacteria Helicobacter pylori
  4. Diet low in fiber such as fresh fruits and vegetables
• In the past a frequent reason for gastrectomy was a gastric ulcer. More recently gastrectomy is primarily used in the treatment of cancer of the stomach. Occasionally gastrectomy is carried out for benign (non-cancerous) polyps
• The most common cancer of the stomach is the adenocarcinoma, a cancer that comes from the cells of the digestive glands of the stomach. There are several different types of adenocarcinoma depending on the type of gland cell from which the tumor comes. A less common cancer is the squamous cell carcinoma from near the esophagus. An interesting tumor of the stomach is the gastric lymphoma. H. pylori infection may also be a cause of adenocarcinoma
• Staging of gastric cancer- Treatment of gastric cancer depends on the degree of spread of the cancer. This spread is defined by the TNM classification
1. Primary Tumor
   • (T) TX: The primary tumor cannot be assessed
   • T0: No evidence of a primary tumor Tis: Tumor limited to mucosa
   • T1: Tumor invades into the submucosa
   • T2: Tumor invades the muscle layer or just beneath the serosa
   • T3: Tumor goes through the serosa without invading adjacent structures
   • T4: Tumor invades the surrounding structures
2. Regional lymph nodes (N). The regional lymph nodes are the nodes immediately about the stomach and nearby arteries. Involvement of more distant nodes such near the liver and duodenum, behind the pancreas, and around the aorta (main artery of the body) are considered distant metastasis (distant spread of the cancer)
   • Nx: Regional lymph node(s) cannot be assessed
   • N0: No metastasis to regional nodes
   • N1: Tumor in 1 to 6 regional lymph nodes
   • N2: Tumor in 7 to 15 regional lymph nodes
   • N3: Tumor in more than 15 regional lymph nodes
3. Distant metastasis (M) Mx: Distant metastasis cannot be assessed M0: No distant metastasis M1: Distant metastasis
• Stages. The stages are determined by the combinations of T, N and M as noted and determine treatment (see below)

Stage 0	Tis	N0	M0
Stage I	T1	N0	M0
	T1	N1	M0
	T2	N0	M0
Stage 2	T1	N2	M0
	T2	N1	M0
	T3	N0	M0
Stage 3	T2	N2	M0
	T3	N1	M0
	T4	N0	M0
	T3	N2	M0
Stage 4	T4	N1	M0
	T1	N3	M0
	T2	N3	M0
	T3	N3	M0
	T4	N2	M0
	T4	N3	M0
	Any T	Any N	M1

History and Examination

• The symptoms of stomach cancer may be vague particularly in the early stages when treatment gives the best results
• Some of the symptoms are
1. A general feeling of being tired or weak
2. Bloating or indigestion soon after eating
3. Vague pain in the upper abdomen
4. Heartburn
5. Nausea and/or vomiting
6. Poor appetite
7. Blood in vomitus or blood in the stool. The stool may be black and foul smelling
• The symptoms are frequently believed to be caused by such problems as stomach ulcer or a virus
• On examination
  1. There may be a fullness in the left upper part of the abdomen
  2. There may be tenderness in the upper abdomen
  3. There may be a mass that can be felt in the upper abdomen

Diagnostic Tests

• The stool may be tested for occult (hidden) blood. Other diseases of the stomach and bowel may cause blood in the stool. These include ulcers and polyps
• Special X-rays of the esophagus and stomach in which the patient drinks a solution containing barium. The solution shows up on X-rays and may outline a tumor. This test is sometimes called an Upper GI Series or barium swallow. (Figure 2)

Figure 2 - Upper G.I. Series showing a large cancer of the upper stomach as outlined by the arrows. Courtesy M. Takriti, M.D.

• Ultrasound examination of the abdomen may show the tumor particularly after it has gone beyond the stomach
• Computerized Tomography (CT) Scan of the abdomen may show the tumor in the stomach particularly when combined with a barium swallow. The CT may also show the spread of the tumor to the lymph nodes, pancreas and liver
• Gastroscopy is an examination in which a long thin tube is inserted down the esophagus into the stomach. The tube contains fiber optics through which light can be passed into the stomach. A small video camera at the other end picks up the image and displays it on a monitor screen. If an abnormal tissue is seen, a small piece of the tissue ( a biopsy) is taken and examined to determine if the tissue is cancer. This is the most accurate test for finding an early cancer (Figure 3)

Figure 3 - Cancer of the stomach as seen through the gastroscope. The lumen is the channel through which food passes. Courtesy M. Takriti, M.D.

Indications for treatment

Treatment of stomach cancer depends on the stage of the cancer, that is, to what degree the tumor has spread. See the Stages above.

• Stage 0
  1. The tumor is only in the mucosa of the stomach
  2. Treatment is subtotal gastrectomy (removal of the part of the stomach that is involved) and removal of the regional lymph nodes (lymph node dissection)
  3. Five year survival rate (percent of patients alive at the end of five years) is approximately 90-95%
• Stage 1
  1. The tumor has penetrated into the submucosa with no more than a few lymph nodes involved or the tumor has gone into the muscle layer but no nodes involved
  2. Treatment depends on where in the stomach the tumor lies
     • Tumor in the lower part of the stomach (near the pylorus)- The lower portion of the stomach is removed (distal subtotal gastrectomy) along with the regional lymph nodes (lymphadenectomy)
     • Tumor involves the upper part of the stomach near the esophagus - The upper part of the stomach is removed (proximal subtotal gastrectomy) along with removal of the lower part of the esophagus (also see Esophagectomy) and lymphadenectomy. Sometimes the entire stomach is removed (total gastrectomy)
     • Tumor diffusely involves the stomach or is near the center of the stomach. A total gastrectomy and lymphadenectomy is carried out
  3. Five year survival rate is about 90% if no nodes are involved
• Stage 2
  1. The tumor involves the mucosa layer of the stomach and 7-15 lymph nodes; involves the muscle layer and less than 7 nodes or penetrates through to the serosa without lymph node involvement
  2. Surgical treatment is similar to that for Stage 1. Radiation and chemotherapy may be added
  3. Five year survival rate is up to 30%
• Stage 3
  1. The tumor involves the muscle layer of the stomach and 7-15 nodes; involves the serosa and 1-15 nodes or extends to adjacent structures without node involvement
  2. As complete removal of the tumor and lymph nodes as possible should be attempted since 10-15% of these tumors are curable. Radiation and chemotherapy are usually added
  3. Five year survival rate is up to 15%
• Stage 4
  1. The tumor has invaded the structures surrounding the stomach; more than 15 nodes are involved or there is a metastasis of the tumor
  2. Cure is rare. Gastrectomy is reserved for those patients with persistent bleeding, severe pain or to prevent blockage of food through the stomach. Chemotherapy is usually used to reduce the severity of the disease but will not produce a cure
  3. Five year survival rate is only 2-3%

Surgical Procedures

Figure 4A - Incision for removal of the stomach.© N.Gordon	Figure 4B - Distal Partial Gastrectomy. The lower end of the stomach is removed. The end of the duodenum is closed. The jejunum is brought up and sutured to the cut end of the stomach in an end-to-side anastomosis. © N.Gordon
Figure 4C - Proximal Partial Gastrectom. The upper end of the stomach is removes. The lower stomach is freed up and brought up and sutured to the esophagus. © N.Gordon	Figure 4D - Total Gastrectomy. The entire stomach is removed. The end of the duodenum is closed. The jejunum is cut and the distal end brought up to the esophagus and sutured. The other end is attached lower down on the jejunum by an end-to-side anastomosis. © N.Gordon

• In addition to removal of the stomach for cancer, gastrectomy may also be performed to remove
  1. A perforated stomach (hole in the stomach wall)
  2. A bleeding stomach ulcer
  3. Scar tissue that causes obstruction (blocks the passage of food)
• The procedures
  1. These procedures are carried out under general anesthesia
  2. A tube is placed in the trachea (windpipe) so the anesthesiologist can control respiration
  3. A nasogastric tube is also placed (tube placed through the nose into the stomach)
  4. An incision is made from just below the breastbone to the umbilicus (belly button) (Figure 4A)
  5. The incision is opened into the peritoneal cavity (the cavity containing the stomach and bowel)
  6. After removal of the stomach, regional lymph nodes are removed with each procedure
• Distal subtotal gastrectomy
  1. This procedure involves removal of the lower part of the stomach (Figure 4B)
  2. The blood vessels going to the distal part of the stomach are clamped and cut
  3. Clamps are placed across the middle of the stomach and the stomach cut between the clamps
  4. Clamps are placed across the beginning of the duodenum and cut across
  5. The distal part of the stomach is removed
  6. The duodenum is closed with sutures (or staples)
  7. A loop of jejunum is then brought up to the cut end of the stomach, the side of the jejunum is opened and the stomach sutured to the side of the jejunum (an end to side anastomosis)
  8. The incision is then closed
• Proximal subtotal gastrectomy
  1. This procedure involves removal of the upper part of the stomach (Figure 4C)
  2. The blood vessels going to the proximal part of the stomach are clamped and cut
  3. Clamps are placed across the end of the esophagus or the upper part of the cardia of the stomach and the stomach cut between the clamps
  4. Clamps are placed across the middle of the stomach and the stomach cut between the clamps
  5. The proximal part of the stomach is removed
  6. The distal portion of the stomach is freed up from its surroundings so that it can be brought up to the esophagus
  7. The distal stomach is then sutured (or stapled) to the esophagus
  8. The incision is then closed
• Total gastrectomy
  1. This procedure removes the entire stomach and regional lymph nodes and frequently includes removal of the spleen and omentum (a fatty apron-like tissue that hangs from the stomach and bowel) (Figure 4D)
  2. The blood vessels going to the stomach are clamped and cut
  3. Clamps are placed across the end of the esophagus and cut between the clamps
  4. Clamps are placed across the beginning of the duodenum and cut across
  5. The stomach is removed
  6. The spleen, part of the pancreas and omentum may also be removed
  7. The duodenum is closed with sutures (or staples)
  8. The jejunum is cut across and the distal end is brought up to the cut end of the esophagus and the esophagus sutured (stapled) to the jejunum
  9. A side opening is made in a loop of jejunum approximately 18 inches (45 cm.) from the anastomosis to the esophagus. The cut end of the jejunum coming from the duodenum is then sutured to the loop as an end to side anastomosis
  10. The incision is closed
• Adjuvant (additional) therapies
  1. Radiation therapy - this involves the use of X-rays or other high energy sources that are directed at any small pieces of tumor that may be left behind in order to kill these tumor cells
  2. Chemotherapy - this involves giving drugs that fight cancer cells either by mouth or through a vein. Chemotherapy is particularly useful if there is spread of the cancer to lymph nodes or distant organs such as the lung

Complications

• Complication related to anesthesia
• Obstruction to the passage of food usually at the point of an anastomosis (point where two parts of the digestive tract are sewn together)
• Bleeding
• Infection of the wound
• Peritonitis (infectious or non-infection inflammation of the lining of the abdomen)
• Breakdown of an anastomosis so that bowel contents leak into the abdomen causing peritonitis
• Pernicious anemia - with a total gastrectomy, vitamin B12 cannot be absorbed thus producing anemia (low red blood cells). Normal nerve function also requires vitamin B12. Injections of vitamin B12 may be necessary
• Heartburn and/or cramping
• Injury to the spleen, gallbladder and pancreas
• Dumping syndrome - Because all or part of the stomach has been removed, food and liquids pass into the small intestine too fast. This may cause nausea, vomiting, diarrhea, cramping and a feeling of dizziness. This can usually be treated by changing the diet to less sugar and more protein and breaking up the diet into small, more frequent meals
• Deep vein thrombosis (clots in the veins if the pelvis of legs) that may lead to pulmonary embolus (clot going to the lung)
• Death

Post-operative care

• Depending on the severity of the surgery, the patient may be sent to a regular surgical room o may be sent to the surgical intensive care unit to be more closely monitored
• The nasogastric tube is left in place and connected to suction to keep the stomach empty. The tube is removed when stomach and bowel function returns to normal, usually in 2 - 3 days
• Fluids are given by vein (intravenously, I.V.)
• Antibiotics are usually given I.V. for 24 hours
• Oxygen may be given by nasal catheter
• Patients are gotten up to sit and walk as they are able
• Gradually the diet is increased from liquids to soft food and then more solid foods. A special diet may be necessary for many of the patients with a gastrectomy
• The wound is kept clean to prevent infection. Lotions should not be applied to the wound
• The patient usually returns to the surgeon's office in one to two weeks after discharge
• If radiation therapy or chemotherapy is given, there will be follow up with a radiologist or oncologist.
• Blood tests, CT scans and other diagnostic tests may be necessary to follow the course of the disease