Partial Gastrectomy
Definition
Gastrectomy is the surgical removal of all or part of the stomach.
Purpose
Gastrectomy is performed for several reasons, most commonly to remove a malignant
tumor or to cure a perforated or bleeding stomach ulcer.
Description
Gastrectomy for cancer
Removal of the tumor, often with removal of surrounding lymph nodes, is the only curative
treatment for various forms of gastric (stomach) cancer. For many patients, this entails
removing not just the tumor but part of the stomach as well. The extent to which lymph
nodes should also be removed is a subject of some debate, but some studies show
additional survival benefit associated with removal of a greater number of lymph nodes.
Gastrectomy, either total or subtotal (also called partial), is the treatment of choice for
gastric adenocarcinomas, primary gastric lymphomas (originating in the stomach), and the
rare leiomyosarcomas (also called gastric sarcomas). Adenocarcinomas are by far the most
common form of stomach cancer and are less curable than the relatively uncommon
lymphomas, for which gastrectomy offers good odds for survival.
After gastrectomy, the surgeon may "reconstruct" the altered portions of the digestive tract
so that it continues to function. Several different surgical techniques are used, but,
generally speaking, the surgeon attaches any remaining portion of the stomach to the small
intestine.
Gastrectomy for gastric cancer is almost always done by the traditional "open" surgery
technique, which requires a wide incision to open the abdomen. However, some surgeons
use a laparoscopic technique that requires only a small incision. The laparoscope is
connected to a tiny video camera that projects a picture of the abdominal contents onto a
monitor for the surgeon's viewing. The stomach is operated on through this incision.
The potential benefits of laparoscopic surgery include less postoperative pain, decreased
hospitalization, and earlier return to normal activities. The use of laparoscopic gastrectomy
is limited, however. Only patients with early stage gastric cancers or those whose surgery is
only intended for palliation-pain and symptomatic relief rather than cure-should be
considered for this minimally invasive technique. It can only be performed by surgeons
experienced in this type of surgery.
Gastrectomy for ulcers
Gastrectomy is also occasionally used in the treatment of severe peptic ulcer disease or its
complications. While the vast majority of peptic ulcers (gastric ulcers in the stomach or
duodenal ulcers in the duodenum) are managed with medication, partial gastrectomy is
sometimes required for peptic ulcer patients who have complications. These include patients
who do not respond satisfactorily to medical therapy, those who develop a bleeding or
perforated ulcer, and those who develop pyloric obstruction, a blockage to the exit from the
stomach.
The surgical procedure for severe ulcer disease is also called an antrectomy, a limited form
of gastrectomy in which the antrum, a portion of the stomach, is removed. For duodenal
ulcers, antrectomy may be combined with other surgical procedures that are aimed at
reducing the secretion of gastric acid, which is associated with ulcer formation. This
additional surgery is commonly a vagotomy, surgery on the vagus nerve that disables the
acid-producing portion of the stomach.
Preparation
Before undergoing gastrectomy, patients may need a variety of tests, such as x rays,
computed tomography scans (CT scans), ultrasonography, or endoscopic biopsies
(microscopic examination of tissue), to assure the diagnosis and localize the tumor or ulcer.
Laparoscopy may be done to diagnose a malignancy or to determine the extent of a tumor
that is already diagnosed. When a tumor is strongly suspected, laparoscopy is often
performed immediately before the surgery to remove the tumor; this avoids the need to
anesthetize the patient twice and sometimes avoids the need for surgery altogether if the
tumor found on laparoscopy is deemed inoperable.
Aftercare
It is important to follow any instructions that have been given for postoperative care. Major
surgery usually requires a recuperation time of several weeks.
Risks
Surgery for peptic ulcer is effective, but it may result in a variety of postoperative
complications. After gastrectomy, as many as 30% of patients have significant symptoms.
An operation called highly selective vagotomy is now preferred for ulcer management, and
is safer than gastrectomy.
After a gastrectomy, several abnormalities may develop that produce symptoms related to
food intake. This happens largely because the stomach, which serves as a food reservoir,
has been reduced in its capacity by the surgery. Other surgical procedures that often
accompany gastrectomy for ulcer disease can also contribute to later symptoms: vagotomy,
which lessens acid production and slows stomach emptying, and pyloroplasty, which
enlarges the opening between the stomach and small intestine to facilitate emptying of the
stomach.
Some patients experience light-headedness, heart palpitations or racing heart, sweating,
and nausea and vomiting after a meal. These may be symptoms of "dumping syndrome,"
as food is rapidly "dumped" into the small intestine from the stomach. This is treated by
adjusting the diet and pattern of eating, for example, eating smaller, more frequent meals,
and limiting liquids.
Patients who have abdominal bloating and pain after eating, frequently followed by nausea
and vomiting, may have what is called the afferent loop syndrome. This is treated by
surgical correction. Patients who have early satiety (feeling of fullness after eating),
abdominal discomfort, and vomiting may have bile reflux gastritis (also called bilious
vomiting), which is also surgically correctable. Many patients also experience weight loss.
Reactive hypoglycemia is a condition that results when blood sugar becomes too high after
a meal, stimulating the release of insulin, about two hours after eating. A high-protein diet
and smaller meals are advised.
Ulcers recur in a small percentage of patients after surgery for peptic ulcer, usually in the
first few years. Further surgery is usually necessary.
Vitamin and mineral supplementation is necessary after gastrectomy to correct certain
deficiencies, especially vitamin B12, iron, and folate. Vitamin D and calcium are also needed
to prevent and treat the bone problems that often occur. These include softening and
bending of the bones, which can produce pain, and osteoporosis, a loss of bone mass.
According to one study, the risk for spinal fractures may be as high as 50% after
gastrectomy.
Depending on the extent of surgery, the risk for post-operative death after gastrectomy for
gastric cancer has been reported as 1-3% and the risk of non-fatal complications as 9-18%.
Normal results
Overall survival after gastrectomy for gastric cancer varies greatly by the stage of disease
at the time of surgery. For early gastric cancer, the five-year survival rate is up to 80-90%;
for late-stage disease, the prognosis is bad. For gastric adenocarcinomas that are amenable
to gastrectomy, the five-year survival rate is 10-30%, depending on the location of the
tumor. The prognosis for patients with gastric lymphoma is better, with five-year survival
rates reported at 40-60%.
Most studies have shown that patients can have an acceptable quality of life after
gastrectomy for a potentially curable gastric cancer. Many patients will maintain a healthy
appetite and eat a normal diet. Others may lose weight and not enjoy meals as much. Some
studies show that patients who have total gastrectomies have more disease-related or
treatment-related symptoms after surgery and poorer physical function than patients who
have subtotal gastrectomies. There does not appear to be much difference, however, in
emotional status or social activity level between patients who have undergone total versus
subtotal gastrectomies.
Antrectomy
A surgical procedure for ulcer disease in which the antrum, a portion of the stomach,
is removed.
Laparoscopy
The examination of the inside of the abdomen through a lighted tube, sometimes
accompanied by surgery.