Gastric Cancer Classification Overview

A set of question-and-answer flashcards covering the Lauren, WHO (2019), and TCGA (2014) classification systems for gastric cancer, including subtypes, histology, location, age distribution, etiology, spread patterns, and prognostic implications.

What are the three main categories in the Lauren classification of gastric cancer?

Intestinal, Diffuse, and Mixed types.

Which five histologic subtypes are listed in the 2019 WHO classification of gastric cancer?

Tubular, Papillary, Mucinous, Poorly Cohesive, and Mixed.

Name the four molecular subtypes in the 2014 TCGA classification of gastric cancer.

EBV-positive, MSI-high, Genomically Stable (GS), and Chromosomal Instability (CIN).

Which Lauren subtype of gastric cancer is the most common?

Intestinal type.

Which WHO histologic subtype of gastric cancer is most frequently encountered?

Tubular carcinoma.

What is the most common molecular subtype according to TCGA?

Chromosomal Instability (CIN).

Describe the histologic appearance of intestinal-type gastric cancer.

Gland-forming adenocarcinoma.

What histologic feature characterizes diffuse-type gastric cancer?

Sheets of signet-ring cells with little or no gland formation.

How does a tubular carcinoma appear histologically under the WHO scheme?

Well-formed glands resembling intestinal architecture.

What histologic pattern defines papillary adenocarcinoma of the stomach?

Finger-like papillary projections.

Which WHO subtype shows abundant extracellular mucin pools?

Mucinous carcinoma.

Describe the key histology of poorly cohesive gastric carcinoma.

Scattered or isolated tumor cells, often including signet-ring cells.

Where in the stomach do intestinal-type cancers usually arise?

Predominantly in the antrum.

Which age group is more often affected by diffuse-type gastric cancer?

Younger patients.

List two principal etiologic factors for intestinal-type gastric cancer.

Helicobacter pylori infection and dietary factors (e.g., smoked/salted foods).

Which germline mutation is strongly associated with diffuse-type gastric cancer?

CDH1 (E-cadherin) mutation.

Match each TCGA subtype with its characteristic alteration: EBV-positive, MSI-high, Genomically Stable, Chromosomal Instability.

EBV-positive – Epstein-Barr virus infection; MSI-high – DNA mismatch-repair defect; Genomically Stable – CDH1 mutation; Chromosomal Instability – TP53 mutation.

How do intestinal and diffuse gastric cancers typically spread?

Intestinal type spreads hematogenously; diffuse type spreads via peritoneal and lymphatic routes.

Compare the general prognosis of intestinal- versus diffuse-type gastric cancer.

Intestinal type generally has a better prognosis, whereas diffuse type has a worse prognosis.

Which TCGA molecular subtype is associated with the most favorable prognosis?

MSI-high tumors.

Which TCGA molecular subtype is linked to the poorest prognosis?

Genomically Stable (GS) tumors.