Ch. 50 Weight Loss and Early Satiety Flashcards
Why is mortality rate so high for gastric cancer?
Due to vague and often nonspecific presenting symptoms + low rate of screening, particularly in US, most pts dx with gastric cancer already found to be stage III or stage IV and unresectable
Are there specific findings on physical exam?
- Usually non-specific and often absent
- If pt does have physical findings, likely that they also have advanced disease
- If anterior gastric tumor, as it grows it may become palpable in epigastric region
- Advanced:
- Palpable left supraclavicular nodes (Virchow’s nodes)
- Periumbilical lymphadenopathy (Sister Mary Joseph nodes)
- Left axillary node (Irish’s node)
- If located in antrum or more distal towards pylorus, may grow into hepaticoduodenal ligament and lead to obstructive jaundice and elevated LFTs
Types of gastric adenocarcinoma
Intestinal
- Well differentiated
- Distal stomach
- 2/2 environmental factors (smoking, alcohol, poor diet, H. pylori)
- Decreasing in incidence
- Discrete mass
- Progressive evolution to cancer over years
Diffuse:
- Poorly or undifferentiated
- Anywhere, but most often proximal stomach
- 2/2 to congenital disorders
- No change in incidence
- Generalized gastric hypertrophy (thickening)
- Aggressive and rapid progression
What is Linitis Plastica?
Diffuse-type gastric cancer = highly metastatic and aggressive –> rapid progression –> cancer in esophagus or duodenum + infiltration of entire gastric wall (“linitis plastic”)
Stiff, undistensible gastric wall that develops after it is infiltrated with tumor
What is the vascular supply to the stomach?
Involves 4 major arteries all derived from celiac artery:
L & R gastric arteries on lesser curve
L & R gastroepiploic arteries on greater curve
Why do patients with gastric cancer get iron deficiency anemia?
Anemia is due to slow intermittent bleeding of the tumor. As the patient loses blood through GI tract in form of melena, there is also iron and heme loss along with RBCs.
Patients often do not show signs of anemia in acute setting b/c body has not yet compensated for the losses. It is in the chronic setting that one will see chronic anemic changes.
Workup:
What is the best way to dx a pt with suspected gastric cancer?
Once dx of gastric cancer is established, what further workup is recommended?
Upper endoscopy
Endoscopic U/S - assists with TNM staging
CT scan of abdomen –> confirm that pt = surgical candidate (r/o liver mets + distant suspicious lymph nodes that were missed on EUS)
Mgmt:
Partial or total gastrectomy
Gastrojejunostomy or esophagojejunostomy will need to be constructed
Mgmt:
What is the role of HER2 Gene Amplification and Chemotherapy?
HER2 overexpression = molecular abnormality that inc. aggressive nature of breast cancer
Recently, evidence that there is a role of HER2 overexpression in gastric cancer pts leading to poorer outcomes and more aggressive disease
What are the other types of gastric cancer other than gastric adenocarcinoma?
- Adenocarcinoma (90%)
- GIST, carcinoids, lymphomas
GIST
- What are GISTs? What was it previously known as?
- Where do they originate?
- Where is it found?
- What are the symptoms?
- How is it diagnosed?
- What is the tumor marker?
- What is the prognosis?
- Treatment?
- Is there a need for lymph node dissection?
- Chemo for metastatic or advanced disease?
- Mesenchymal tumors of variable malignant potential / Leiomyosarcoma
- Originate from the interstitial cells of Cajal (GI pacemaker cells) within GI tract
- GI tract — “esophagus to rectum” —most commonly found in stomach (60%), small bowel (30%), duodenum (5%), rectum (3%), colon (2%), esophagus (1%)
- GI bleed, occult GI bleed, abdominal pain, abdominal mass, nausea, distension
- CT, EGD, colonoscopy
- c-KIT (CD117 antigen) expression
- Local spread, distant metastasis… poor long-term prognosis
- Resect with negative margins, +/- chemo
- NO, rarely spread through lymphatics…
- Imatinib therapy (TK-inhibitor)
Gastric Lymphoma: (MALToma)
- What is it?
- What is the most common site?
- What is the causative agent?
- What is the medical treatment?
Gastric Lymphoma: (DLBL)
- Treatment?
MALT
- Mucosal-Associated Lymphoproliferative Tissue
- Stomach (70%)
- H. pylori
- Nonsurgical–treat for H. pylori - Completely treatable with 3x therapy
Diffuse large B cell
- CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, prednisone) followed by radiation
Complications:
Why do patients get dumping syndrome after gastric resection?
Diarrhea 2/2 dumping syndrome = one of the most common complications of gastric resection
Dumping syndrome is caused by rapid distribution of food within small intestine in absence of regulatory effect of pyloric sphincter –> hyperosmolar state that ensues within intestines –> inc. water secretion into lumen –> diarrhea + occassional hypotension
How are anastomotic leaks identified and treated?
ID: upper GI with gastrografin should be ordered –> contrast extravasation will confirm leak
Tx: SOURCE CONTROL FIRST (re-operation… see if you can salvage initial operation)
Gastric Cancer
- Symptoms associated with gastric cancer?
- What are the most common early symptoms?
- What is the most common symptom?
- “WEAPON”
- Weight loss
- Emesis
- Anorexia
- Pain/epigastric discomfort
- Obstruction
- Nausea
- Mild epigastric discomfort and indigestion
- Weight loss
Gastric Cancer
- What does the pt with gastric cancer have if he or she has proximal colon distension?
- What is the symptom of proximal gastric cancer?
- What is Blumer’s shelf?
- Colonic obstruction by direct invasion (rare)
- Dysphagia (gastroesophageal jxn/cardia)
- Solid peritoneal deposit anterior to the rectum, forming a “shelf,” palpated on rectal exam
What is a surveillance laboratory finding for gastric cancer?
CEA elevated in 30% of cases (if +, useful for post-op surveillance)
How do gastric adenocarcinomas metastasize?
Which pts with gastric cancer and NONoperative?
Hematogenously and lymphatically
- Distant metastasis (e.g., liver mets) / 2. Peritoneal implants
- What is the genetic alteration seen in >50% of pts with gastric cancer?
- What is the treatment?
- What operation is performed for tumor in the:
- Antrum?
- Midbody?
- Proximal?
- What type of anastomosis?
- What is adjuvant tx?
- What is the 5-year survival rate for gastric cancer?
- P53
- Surgical resection with wide (>5 cm checked by frozen section) margins and lymph node dissection
- Operation:
- Antrum: Distal subtotal gastrectomy (75% of stomach removed)
- Midbody: Total gastrectomy (stomach removed and Roux-en-Y limb sewn to esophagus)
- Proximal: Total gastrectomy
- Billroth II or Roux-En-Y
- Stages II and III: post-op chemo and radiation
- 25% of pts alive 5 years after dx in US (in Japan, 50% alive - due to aggressive screening and capturing early cancers)
