R2 indicates gross (macroscopic) residual disease in the absence of distant metastasis
Role of Surgery
-if distal 2/3, subtotal gastrectomy. Proximal of distal margin of 4cm or greater. Use frozen sections for margins. Recon=B2 or Roux-en-y. No survival benefit for total gastrectomy
- Total Gastrectomy for proximal (upper 1/3) tumor
Most controversial area in gastric cancer. Need 15 nodes for adequate staging.
Describe N1,N2 and N3 lymph node station
N1 refers to perigastric lymph node station along lesser curvature(station 1,3,5) and greater curvature (station 2,4,6).
N2 involve nodes around left gastric artery (station 7), common hepatic artery (station 8), celiac artery station (9) and splenic artery (10,11)
More distant lymph node including para-aortic are grouped as N3,N4.
Describe D0,D1, and D2 lymph node dissection
D0- Incomplete resection of N1 lymph node
D1- D1 involves gastrectomy and removal of proximal or distal part of teh stomach or entire stomach (distal or total resection), including the greater and lesser omental LN which would include LN along the righ and left cardiac, alonger lesser and greater curv, suprapyloric along righ gastric artery infrapyloric area).
D2- involve D1 + removal of the anterior leaf of transverse mesocolon, and all the nodes along corresponding arteies (i.e left gastric, common hepatic, celiac splenic hilum and splenic artery). A splenectomy (to remove station 10and 11) is required for D2 lymph node dissection for proximal gastric tumors.
The most common location of gastric cancer is
Antrum has 40% of gastric cancers
Adenomatous polyps confer what % of risk for gastric cancer? How do you treat these?
Adenomatous polyps - 10-20% risk of cancer.
Tx: endoscopic resection
Which one has the less favorable prognosis?Intestinal gastric cancer or diffuse gastric cancer?
Diffuse gastric cancer is less favorable prognosis than intestinal gastric cancer
What is the survival rate for stage II disease in linitis plastica?
Stage II disease - <50% 5-year survival rate
What are options for chemothreapy in linitis plastica?
Chemotherapy - 5FU, doxorubicin, mitomycin C
A patient with gastric cancer has an obstruction: What do you do to palliate this? How will your management change if it is a proximal vs distal lesion?
Obstruction - proximal lesions can be stented; distal lesion bypasses with gastrojejunostomy?
Which type of gastric adenocarcinoma has glands on histology? Which type doesn't?
Intestinal gastric cancer: Glands on histology
Diffuse gastric cancer (linitis plastica): No glands
Which type of gastric adenocarcinoma has blood invasion on histology? Which type has lymphatic invasion on histology?
Intestinal gastric cancer: Blood invasion on histology
Duffuse gastric cancer (linitis plastica): Lymphatic invasion
In which populations do you find intestinal gastric cancer
Intestinal gastric cancer: increased in high-risk populations, older men