Gastric Adenocarcinoma Flashcards
What common pathway do many risk factors for gastric cancer share?
Chronic inflammation leading to dysplasia.
What are some environmental risk factors for gastric cancer?
Long-term H. pylori infection
atrophic gastritis
gastroesophageal reflux disease
pernicious anemia
tobacco use
high-salt foods
and smoked meats high in nitrates.
What role does ascorbic acid play in reducing gastric cancer risk?
from fresh fruits and vegetables can neutralize carcinogenic nitrogen compounds and oxygen free radicals.
What genetic factors are linked to an increased risk of gastric cancer?
Overexpression of COX2
cyclin D2
p53 mutations
microsatellite instability (MSI).
Name some inherited syndromes associated with familial gastric cancer.
Hereditary diffuse gastric cancer
hereditary nonpolyposis colorectal cancer
Li-Fraumeni syndrome
and polyp-associated gastric cancer syndromes.
What percentage of primary gastric malignancies are adenocarcinomas?
95% of primary gastric malignancies are adenocarcinomas
What are the two other types of primary gastric malignancies besides adenocarcinoma?
Lymphoma (4%) and gastrointestinal stromal tumor (GIST, <1%).
What is the Borrmann classification of gastric cancer?
A classification based on the gross appearance of endoscopic findings:
Type I: Polypoid
Type II: Fungating
Type III: Ulcerated
Type IV: Diffusely infiltrating (linitis plastica)
What is linitis plastica in the context of gastric cancer?
Type IV gastric cancer that is diffusely infiltrating, leading to a rigid, thickened stomach wall.
What are the two histologic subtypes of gastric adenocarcinoma according to the Lauren classification?
Intestinal type and diffuse type
What characteristics are associated with the intestinal type of gastric adenocarcinoma?
increasing incidence with age
often linked to environmental risk factors
or precancerous conditions like atrophy and metaplasia.
What cell type characterizes the diffuse type of gastric adenocarcinoma?
Tiny clusters of small, uniform, signet ring cells.
How does the diffuse type of gastric adenocarcinoma typically spread?
It has high rates of early metastasis through
submucosal lymphatic spread and transmural extension.
Which type of gastric adenocarcinoma is more likely to be poorly differentiated?
The diffuse type
Why is gastric cancer often diagnosed at a late stage?
Symptoms are typically vague and nonspecific, often mistaken for dyspepsia, peptic ulcer disease, or gastritis
What are some common symptoms of gastric cancer?
Early satiety, weight loss, obstruction, dysphagia, and bleeding, with 40% of patients having some form of anemia at diagnosis.
What is Sister Mary Joseph’s node, and what does it signify?
A palpable periumbilical node that indicates distant metastatic nodal disease, historically observed as predictive of advanced intraabdominal disease
Name three eponymous signs of distant metastatic disease in gastric cancer
Virchow’s node (supraclavicular adenopathy)
Krukenberg tumor (ovarian metastases)
Blumer’s shelf (peritoneal metastases palpated in the pouch of Douglas).
What are the primary tools for clinical staging and diagnosis of gastric cancer?
Endoscopy
endoscopic ultrasound (EUS)
CT
PET
MRI
diagnostic laparoscopy with peritoneal washings.
How is endoscopy used in the diagnosis of gastric adenocarcinoma?
It confirms diagnosis, obtains biopsy specimens, and localizes the tumor for surgical planning, especially in relation to the gastroesophageal junction (GEJ).
What is the Siewert-Stein classification, and what does it describe?
It classifies proximal gastric tumors based on their location relative to the GEJ:
Type I: Distal esophagus, 1–5 cm above GEJ
Type II: Cardia, up to 1 cm above and 2 cm below GEJ
Type III: Subcardial, 2–5 cm below GEJ
Who undergoes selective screening with upper endoscopy for gastric cancer in the United States?
Patients with specific risk factors
such as gastric polyps, pernicious anemia, or certain genetic disorders
What is recommended by the NCCN regarding biopsy for gastric cancer diagnosis?
Taking multiple biopsy specimens from different areas of the lesion.
How are Siewert type III lesions classified and treated?
They are considered gastric cancers and should be treated according to gastric cancer protocols, ensuring adequate esophageal resection to achieve negative margins
What is the role of endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) in gastric adenocarcinoma?
EMR or ESD can be definitive treatment for small lesions (< 2 cm) confined to Tis or T1a tumors limited to the mucosa
Why is PET sometimes used alongside CT in gastric cancer staging?
To identify occult metastatic disease or evaluate suspicious lesions found on CT; PET can also assess response to neoadjuvant therapy
What is the role of endoscopic ultrasound (EUS) in the staging of gastric adenocarcinoma?
EUS provides accurate assessment of tumor depth and perigastric lymph node involvement; fine-needle aspiration (FNA) is used for suspicious nodes.
What does the NCCN recommend for staging laparoscopy in gastric cancer patients?
Staging laparoscopy is recommended for all patients with T2 or greater gastric cancer with no prior evidence of metastatic disease on imaging
What is the significance of positive peritoneal cytology in gastric cancer staging?
It indicates occult carcinomatosis and is associated with a poorer prognosis and lower disease-free survival
What is the typical treatment strategy for patients with T1 gastric tumors without nodal involvement or distant disease?
They are usually offered upfront surgery.
When is neoadjuvant chemotherapy indicated for gastric adenocarcinoma patients?
with T2 or T3 invasion depth
or any evidence of adenopathy
What is hyperthermic intraperitoneal chemotherapy (HIPEC), and when is it considered in gastric cancer treatment?
offered to patients with low-burden or occult peritoneal disease after neoadjuvant therapy and during gastrectomy to treat peritoneal metastasis.
What types of nodal involvement or conditions exclude gastric cancer patients from resection for cure?
Distant metastasis
N3 (root of mesentery nodal involvement)
N4 (paraaortic nodal involvement)
major vascular encasement (excluding splenic vessels).
What is the purpose of molecular profiling in gastric cancer?
To understand the biological behavior of the tumor and identify targets for biologic immune therapy.
Why is HER2 testing recommended for gastric adenocarcinoma patients with metastatic disease?
can influence treatment options, as HER2-targeted therapies are available
What role does PD-L1 expression play in gastric cancer treatment?
PD-L1 expression influences treatment decisions, as its pathway inhibits T cell proliferation and is targeted in immunotherapy
What demographic and clinical features are associated with MSI in gastric cancer?
MSI is associated with older age, female sex, fewer lymph node metastases, and a distal stomach location.
How does MSI status affect survival outcomes compared to microsatellite stable (MSS) gastric tumors?
Patients with MSI gastric tumors generally have superior survival outcomes compared to MSS patients
Why is chemotherapy typically not recommended for MSI gastric cancer patients?
chemotherapy may worsen survival in MSI patients, unlike in MSS patients.
What immunologic characteristic is reported in MSI gastric cancer subtypes?
Strong immunogenicity with increased expression of checkpoint ligands like PD-L1, making these patients more suitable for immunotherapy
What does a D1 nodal dissection involve?
Gastrectomy with resection of the greater and lesser omenta and perigastric lymph nodes (stations 1 to 7).
Which nodal stations are included in a D2 nodal dissection?
D1 stations plus those along the left gastric, common hepatic, celiac, splenic artery, and splenic hilum (stations 1 to 12).
What additional clearance does a D3 nodal dissection include?
Periaortic nodes (stations 1 to 16)
What were the findings of the Dutch Gastric Cancer Trial regarding D2 lymphadenectomy?
It showed improved disease-specific survival for D2 dissection over D1.
What are the NCCN guidelines for lymphadenectomy in gastric cancer?
They recommend a D2 dissection without splenectomy.
What is “D1 over” and when is it used?
“D1 over” is a modified D2 dissection where only certain nodes are removed without full dissection of the splenic artery and hilum
What is the typical approach for cancers in the distal stomach?
Distal or subtotal gastrectomy, with a 4- to 5-cm gross margin (Proximal)
distal transection > Across the first portion of the duodenum, just distal to the pylorus.
What vessel is divided in the process of a distal gastrectomy?
The right gastroepiploic artery.
Which lymph nodes are targeted with high ligation of the left gastric artery?
Station 7 lymph nodes.
What is the common reconstruction method after distal or subtotal gastrectomy?
Roux-en-Y reconstruction
What is a Billroth II gastrojejunostomy typically reserved for?
Patients with stage IV disease due to its risk of alkaline reflux gastritis
What is the role of frozen section analysis during gastrectomy?
To assess surgical margins before reconstruction, with further resection needed if margins are positive.
What is recommended if a distal gastrectomy shows a positive margin?
Further resection is mandated.
When is a total gastrectomy typically used?
For most midbody and proximal tumors.
What type of gastrectomy is sometimes used for small gastric tumors near the gastroesophageal junction (GEJ) but is uncommon in the United States?
Proximal gastrectomy
How do oncologic outcomes of proximal gastrectomy compare to total gastrectomy?
They are believed to be equivalent, although the total lymph node harvest may be lower with proximal gastrectomy.
What complications were reported in earlier studies following proximal gastrectomy?
Higher rates of anastomotic stenosis and reflux esophagitis
How does contemporary proximal gastrectomy differ from earlier versions?
Contemporary proximal gastrectomy does not typically resect the majority of the stomach, allowing for a larger remnant pouch.
What advantage does a larger remnant stomach pouch offer in proximal gastrectomy?
It may improve postoperative nutrition
According to Japanese studies, what percentage of the stomach should remain for proximal gastrectomy to offer better functional results than total gastrectomy?
More than 50% of the stomach should remain
When is a total gastrectomy preferred over proximal gastrectomy due to bile reflux concerns?
When more than 50% of the stomach tissue needs to be removed
For which patients might a proximal gastrectomy be particularly appropriate?
Patients with less physiologic reserve to tolerate a total gastrectomy
How is exposure for dissection and reconstruction achieved in proximal gastrectomy?
By dividing the diaphragm in the midline after ligating the crossing phrenic vein
What anatomical structure is mobilized by opening the diaphragmatic hiatus in proximal gastrectomy?
The distal mediastinal esophagus.
What type of anastomosis is performed in proximal gastrectomy, and over what device is it done?
A primary esophagogastrostomy in an end-to-side manner, performed over a nasogastric (NG) tube.
Where does the anastomosis lie after reapproximation of the diaphragm in proximal gastrectomy?
In the low mediastinum.
For which patients is pylorus-preserving gastrectomy indicated?
Patients with early gastric cancer (T1N0M0) located in the middle-third of the stomach, at least 4.0 cm away from the pylorus.
When might surgery be considered for advanced gastric cancer?
In carefully selected patients, particularly those requiring a multivisceral en bloc resection
What is the purpose of a multivisceral en bloc resection in locally advanced gastric adenocarcinoma?
To achieve an R0 resection, leading to a significant survival benefit over palliative resection or chemotherapy alone
What procedures might be involved in multivisceral resection for gastric cancer invading nearby organs?
Distal pancreatectomy, splenectomy, or pancreaticoduodenectomy
For patients with limited peritoneal disease (PCI ≤ 7), what treatment may be beneficial?
Cytoreductive surgery (CRS) and HIPEC, in addition to systemic chemotherapy and gastrectomy.
Why is preoperative diagnostic or staging laparoscopy important for patients with gastric cancer?
To identify patients who may benefit from an aggressive CRS and HIPEC approach
What is the leak rate associated with distal gastrectomy?
1% to 2%.
What is the authors’ practice regarding NG tube management after distal gastrectomy?
The NG tube is typically removed in the operating room
When do patients typically begin a clear liquid diet after distal gastrectomy?
The night of surgery or the following day.
What is the expected discharge timeline for distal gastrectomy patients on an ERAS pathway?
Postoperative day 3 to 5.
How does the postoperative care for total gastrectomy differ from distal gastrectomy?
Total gastrectomy requires a longer hospital stay and a slower diet progression.
What study is performed for total gastrectomy patients with an esophageal anastomosis, and when?
A fluoroscopic swallow study on postoperative day 3
How is diet progression managed for total gastrectomy patients after a swallow study?
Progression from liquids to soft foods, with discharge on either a soft or regular diet
When is a jejunal feeding tube typically used post-gastrectomy?
Only in select cases, such as older patients with preoperative weight loss, malnutrition, or frailty
For which patients has systemic chemotherapy shown a survival advantage in combination with surgery?
Patients with gastric adenocarcinoma greater than T2N0 disease.
What are common first-line chemotherapy regimens for gastric adenocarcinoma?
FLOT (5FU, leucovorin, oxaliplatin, docetaxel)
CAPOX (capecitabine and oxaliplatin)
FOLFOX (5FU, leucovorin, oxaliplatin)
ECF (epirubicin, cisplatin, 5FU).
Why is there a shift from adjuvant to neoadjuvant therapy in gastric cancer?
Due to high failure rates in completing adjuvant therapy, often from surgical complications and poor patient performance status
What were the findings of the MAGIC trial regarding perioperative chemotherapy?
Improved outcomes in local recurrence, distant metastases, and 5-year overall survival for patients receiving perioperative chemotherapy with ECF vs. surgery alone
What was the outcome of the FLOT4-AIO trial comparing FLOT to the MAGIC regimen?
four preoperative and four postoperative cycles of FLOT.
significant improvement in median overall survival with the FLOT regimens (50 vs. 35 months)
MAGIC trial : a 3-week cycle of ECF preoperatively and three additional cycles postoperatively.
What was the outcome of the CheckMate-649 trial regarding nivolumab for advanced gastric cancer?
Nivolumab combined with chemotherapy improved survival in PD-L1 positive advanced gastric, GEJ, and esophageal cancer compared to chemotherapy alone (13.8 vs. 11.6 months median survival)
How does HER2 overexpression impact gastric cancer treatment?
HER2 plays a role in cell growth and proliferation, and therapies targeting HER2 (such as trastuzumab) can improve survival in HER2-positive advanced gastric cancer
What does postoperative surveillance for gastric cancer include?
History and physical examination, basic laboratory tests, and a CT scan every 3 to 6 months for 1-2 years
then every 6 to 12 months until 5 years post-treatment
When do most cases of recurrent gastric cancer present after initial treatment?
Within the first 4 to 5 years.
What is the first-line therapy for recurrent gastric cancer?
Two-drug chemotherapy regimens, with three-drug regimens for patients with good performance status.
Can surgery be considered for recurrent gastric cancer?
Yes, for resectable locoregional recurrence in medically fit patients, though not strongly supported by prospective data.
What percentage of gastric cancer patients initially present with unresectable or metastatic disease?
Approximately 50%.
What are common symptoms of progressive gastric cancer?
Bleeding, obstruction, nausea, and pain.
How can bleeding from gastric cancer be managed palliatively?
Endoscopic coagulation
with adjuncts like external beam radiation or angiographic embolization for recurrent bleeding.
What are some palliative options for managing gastric outlet obstruction in gastric cancer?
External beam radiation therapy
chemotherapy
endoscopic stent placement
surgical gastrojejunostomy
venting gastrostomy
selective palliative gastrectomy.
What supportive options may be required for patients who cannot tolerate an oral diet due to gastric cancer?
A gastrostomy or jejunal feeding tube for hydration and nutritional support
