Gastroenterology · Oncology

Gastric Cancer

USMLE2PANCE
7

Bets

The facts most likely to be tested

1

Helicobacter pylori infection is the single most significant modifiable risk factor for the development of adenocarcinoma of the stomach.

Confidence:
2

Virchow node (left supraclavicular lymphadenopathy) and Sister Mary Joseph nodule (periumbilical metastasis) are classic signs of metastatic gastric malignancy.

Confidence:
3

Linitis plastica describes a diffuse, infiltrative gastric cancer that results in a leather bottle stomach appearance on imaging.

Confidence:
4

Krukenberg tumor refers to the bilateral metastasis of gastric adenocarcinoma to the ovaries.

Confidence:
5

Signet ring cells are the hallmark histological finding of diffuse-type gastric cancer.

Confidence:
6

EGD with biopsy is the gold standard diagnostic test for confirming the presence and histological subtype of gastric cancer.

Confidence:
7

Weight loss, early satiety, and iron deficiency anemia in an older patient are the classic alarm symptoms requiring urgent endoscopic evaluation.

Confidence:

Vignette unlocked

A 68-year-old male presents to the clinic with a 3-month history of progressive weight loss, early satiety, and epigastric pain. Physical examination reveals a palpable, hard left supraclavicular lymph node and a firm, periumbilical nodule. Laboratory studies demonstrate a microcytic anemia with a hemoglobin of 9.2 g/dL. The patient has a long-standing history of untreated dyspepsia.

What is the most likely diagnosis and the most appropriate next step in management?

+Reveal answer

Gastric adenocarcinoma; EGD with biopsy.

The patient presents with classic alarm symptoms and metastatic signs (Virchow node and Sister Mary Joseph nodule) highly suggestive of gastric cancer, requiring EGD for definitive tissue diagnosis.

Mo

Depth

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High yield triage

Etiology / Epidemiology

Strongest risk factor is H. pylori infection. Other risks include smoked/salted foods, nitrates, and atrophic gastritis.

Clinical Manifestations

Presents with weight loss and early satiety. Look for Virchow's node and Sister Mary Joseph nodule.

Diagnosis

Upper endoscopy with biopsy is the gold standard. CT scan is used for staging.

Treatment

Surgical resection is the only curative option. Chemoradiation is used for adjuvant therapy.

Prognosis

Overall 5-year survival is <30%. Metastasis to liver and peritoneum is common.

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Epidemiology & Etiology

Most cases are adenocarcinoma. Incidence is higher in East Asia, South America, and Eastern Europe. Chronic H. pylori infection leads to intestinal metaplasia, the precursor to malignancy.

Pertinent Anatomy

The lesser curvature is the most common site for gastric adenocarcinoma. Tumors can be classified as Borrmann classification based on gross appearance.

Pathophysiology

Chronic inflammation leads to atrophic gastritis, followed by intestinal metaplasia and dysplasia. Genetic mutations in CDH1 (E-cadherin) are associated with diffuse-type gastric cancer.

Clinical Manifestations

Patients often present with dyspepsia, anemia, and occult GI bleeding. Red flag symptoms include unintentional weight loss and dysphagia. Metastatic signs include Virchow's node (left supraclavicular) and Sister Mary Joseph nodule (umbilical).

Diagnosis

Upper endoscopy with biopsy is the definitive diagnostic test. Endoscopic ultrasound is the most accurate modality for determining the depth of invasion (T-staging).

Treatment

Localized disease requires gastrectomy with lymph node dissection. Contraindications for surgery include distant metastasis or extensive peritoneal involvement. 5-Fluorouracil and cisplatin are standard components of perioperative chemotherapy.

Prognosis

Prognosis is poor due to late-stage presentation. Peritoneal carcinomatosis is a frequent cause of mortality. Patients require long-term monitoring for B12 deficiency post-gastrectomy.

Differential Diagnosis

Peptic Ulcer Disease: relieved by food or antacids

Gastric Lymphoma: often associated with MALToma

Gastrointestinal Stromal Tumor (GIST): usually submucosal

Menetrier disease: protein-losing gastropathy with rugal hypertrophy

Gastritis: diffuse mucosal inflammation without mass