A Case Of Gastric Carcinoma

A 72-year-old Japanese immigrant was brought in by his family with complaints of difficulty in eating, vague abdominal pain, and weight loss. Endoscopy and biopsy confirmed gastric adenocarcinoma. Liver metastases were found on abdominal CT. The family and the patient chose only comfort measures and the patient died 6 months later.

Case Discussion:  

Introduction: Gastric cancer is a malignant neoplasm of the stomach, usually adenocarcinoma..

Epidemiology:  The median age at diagnosis is 70 years and median age at death from gastric cancer is 73 years.

• Stomach cancer occurs in 10.8 per 100,000 men and 5.4 per 100,000 women in a year. In 2008, the United States prevalence was 37,739 men and 28,271 women, with a lifetime risk of 0.88%.

• High rates of stomach cancer occur in Japan, China, Chile, and Ireland.

Pathophysiology: Eighty-five percent of stomach cancers are adenocarcinomas with 15% lymphomas and GI stromal tumors.

 Adenocarcinoma is further divided into two types:

~ Diffuse type—Characterized by absent cell cohesion, these tumors affect younger individuals infiltrating and thickening the stomach wall; the prognosis is poor. Several susceptibility genes

have been identified for this type of cancer.

~ Intestinal type—Characterized by adhesive cells forming tubular structures, these tumors frequently ulcerate.

Etiology: 

• Most tumors are thought to arise from ingestion of nitrates that are converted by bacteria to carcinogens.

Exogenous and endogenous factors contribute to the process of carcinogenicity by creating gastritis, loss of acidity, and bacterial growth.

Other risk Factors For gastric cancer include:

• Previous gastric surgery
• Atrophic gastritis (including
• Postsurgical vagotomized patients
• Pernicious anemia 
• Familial adenomatous polyposis 
• Hereditary nonpolyposis colorectal cancer 
• Individuals infected with certain H. pylori bacteria (cytotoxinassociated gene A) are at increased risk of gastric adenocarcinoma
• Smoking, 
• Low socioeconomic class, 
• Lower educational level, 
• Exposure to certain pesticides (e.g., those who work in the citrus fruit industry in fields treated with 2,4-dichlorophenoxyacetic acid [2,4-D], chlordane, propargite, and triflurin10),
• Radiation exposure, and
• Blood type A.

~ Gastric cancer spreads in multiple ways:2

 Local extension through the gastric wall to the perigastric tissues, omenta, pancreas, colon, or liver.

 Lymphatic drainage through numerous pathways leads to multiple nodal group involvement (e.g., intraabdominal, supraclavicular) or seeding of peritoneal surfaces with metastatic nodules occurring

on the ovary, periumbilical region, or peritoneal cul-de-sac.

 Hematogenous spread is also common with liver metastases.

Clinical Features:

• Asymptomatic, if superficial and/or early.

• Upper abdominal pain that ranges from vague to severe.

• Postprandial fullness.

• Anorexia and mild nausea are common.

•Nausea and vomiting occur with pyloric tumors.

• Late symptoms include weight loss and a palpable mass (regional extension).

• Late complications include peritoneal and pleural effusions; obstruction of the gastric outlet; bleeding from esophageal varices or postsurgical site; and jaundice.

• Physical signs are also late features and include:

~ Palpable enlarged stomach with succussion splash (splashing sound on shaking, indicative of the presence of fluid and air in a body cavity).

~ Primary mass (rare).

~ Enlarged liver.

~ Enlarged, firm to hard, lymph nodes (i.e., left supraclavicular [Virchow]), periumbilical region (Sister Mary Joseph node), and peritoneal cul-de-sac (Blumer shelf; palpable on vaginal or rectal examination).

Imaging And Endoscopy

• Diagnosis can be made on endoscopy with biopsy of suspicious lesions. 

• Urgent referral for endoscopy (within 2 weeks) is recommended for patients with dyspepsia who also have GI bleeding, dysphagia, progressive unexplained weight loss, persistent vomiting, iron deficiency anemia, epigastric mass, family history of gastric cancer (onset <50 years), or whose dyspepsia is persistent and they are older than age 55 years.

• Double-contrast radiography is an alternative to endoscopy and can detect large primary tumors but distinguishing benign from malignant disease is difficult.

• Although endoscopy is not necessary when radiography demonstrates a benign-appearing ulcer with evidence of complete healing at 6 weeks, some authors recommend routine endoscopy, biopsy, and brush cytology when any gastric ulcer is identified.

• Some gastric polyps (adenomas, hyperplastic) have malignant potential and should be removed.

• Work-up for metastases includes:

~ Chest radiograph.

~ CT scan or MRI of the abdomen and pelvis.

• Endoscopic sonography is useful as a staging tool when the CT scan fails to find evidence of locally advanced or metastatic disease.

Differential Diagnosis:

• Peptic ulcer—Typical symptoms include epigastric pain (described as a gnawing or burning), occurring 1 to 3 hours after meals and relieved by food or antacids. Patients may also have nausea and vomiting, bloating, abdominal distention, and anorexia. Endoscopy confirms diagnosis 
• Nonulcer dyspepsia—Includes gastroesophageal reflux disease and functional dyspepsia. Classic symptoms of gastroesophageal reflux disease are heartburn (i.e., substernal pain that may be associated with acid regurgitation or a sour taste) aggravated by bending forward or lying down, especially after a large meal; individual symptoms, however, do not help to distinguish these patients from those with peptic ulcer disease. Endoscopy is considered if symptoms fail to respond to treatment (e.g., histamine-2 receptor agonist, proton pump inhibitor) or red flag signs/symptoms occur (e.g., bleeding, dysphagia, severe pain, weight loss).
•  Chronic gastritis—Includes autoimmune (body-predominant) and H. pylori-related (antral-predominant) types; mucosal inflammation (primarily lymphocytes) may progress to atrophy and metaplasia. Abdominal pain and dyspepsia are common symptoms and patients may have pernicious anemia.
• Esophagitis—May be mechanical or infectious (primarily viral and fungal). Symptoms include heartburn (retrosternal wave-like pain that may radiate to the neck or jaw) and painful swallowing (odynophagia) regurgitation of sour or bitter tasting material may occur with obstruction. Barium swallow or esophagoscopy can be used to establish the diagnosis.
•  Esophageal cancer—Relatively uncommon malignancy of two cell types: squamous cell cancers (largely related to smoking, excessive alcohol consumption, and other agents causing mucosal trauma) and adenocarcinomas (usually arising in the distal esophagus related to reflux disease). Symptoms include progressive dysphagia and weight loss; the diagnosis is confirmed on esophagoscopy and biopsy.

Management: Patients may be best managed by an experienced multidisciplinary team.

Pharmacologic

• Chemotherapy using 5-fluorouracil (FU) and doxorubicin with or without cisplatin or mitomycin C is somewhat helpful. 

Referal For Surgery

• Complete resection including adjacent lymph nodes is recommended. For resectable gastric adenocarcinoma, recommendations are free-margin surgery with at least D1 resection (perigastric lymph nodes) combined to removal of a minimum of 15 lymph nodes.

Radiotherapy

Radiation is useful for palliation for pain

Prognosis: 

Surgical morbidity (e.g., anastomotic leaks, infection) occurs in approximately 25% of patients and operative mortality is approximately 3%

• Five-year relative survival for localized disease is 61.5%, for spread to regional nodes is 27.8%, and for metastatic disease is 3%.

• Median survival for grade of tumor decreases from well-differentiated tumors (22.6 months) to undifferentiated (7.6 months).