Pathology -- GI Neoplasia Flashcards
Define adenocarcinoma
Malignant epithelial neoplasm with glandular differentiation
Define squamous cell carcinoma
Malignant epithelial neoplasm with squamous cell differentiation
Define glandular differentiation
- Formation of glands
- Production of mucus (intracellular and/or extracellular)
Architectural malignant features of adenocarcinoma
- Irregularly shaped glands or groups of cells
- Infiltrating growth pattern, either as groups of cells or single cells
Cytologic malignant features of adenocarcinoma (4)
- Neoplastic cells are usually large and irregular in size and shape
- High N/C ratio
- Nuclei irregular in size and shape
- Prominent nucleoli
Miscellaneous malingnant features of adenocarcinoma (3)
- Necrosis
- Frequent mitoses
- Desmoplastic stroma
Describe the histology of invasive (colonic) adenocarcinoma (4)
- Irregular complex glands infiltrating the stroma (upper right corner shows some benign crypts)
- Desmoplastic stroma
- Necrotic debris within glands
- Marked cytoplogic atypia in neoplastic cells (increased nuclear size with great variation in size and shape, increased N/C ratio)
Define dquamous cell differentiaiton
Keratinocyte-like cells with intercellular bridges and/or keratinization
Describe the appearance of keratinocyte-like cells
Polygonal, pavement-like cells with eosinophilic cytoplasm
Architectural malignant features of in situ SCC (2)
- Tumor above the basement membrane
- Architecture approximates that of the normal squamous epithelium (cytology still malignant)
Architectural malignant features of invasive SCC
Irregularly-shaped sheets of cells, sometimes single cells with infiltrating growth pattern
Cytology of SCC (4)
- Neoplastic cells usually large and irregular in size and shape
- High N/C ratio
- Nuclei irregular in size and shape
- Sometimes prominent nucleoli
3 miscellaneous malignant features of SCC
- Necrosis
- Frequent mitoses
- Desmoplastic stroma
Describe the histology of invasive SCC (7)
- Tumor extends beyond the basement membrane and infiltrates the stroma
- Cells are polygonal and focal keratin formation may be seen
- Infiltrative growth pattern
- Desmoplastic stroma
- Cytological atypia
- Keratinization
- Intercellular bridges
What gives invasive SCC a tumor with firm consistency?
The desmoplastic stroma
3 precursor lesions for adenocarcinoma and their specific areas of effect
- Intestinal metaplasia –> dysplasia of glandular mucosa (esophagus and stomach)
- Adenoma (stomach and bowel)
- Dysplasia in the context of chronic inflammatory bowel disease (bowel)
Describe the histology of tubular adenoma
- Nuclear enlargement
- Nuclear stratification
- Lack of maturation
(Versus normal colon on right)
Types of tumors that can be found in the esophagus
- Adenocarcinoma
- Squamous cell carcinoma
Types of tumors that can be found in the stomach
- Adenocarcinoma (intestinal type and diffuse, signet ring cell, type)
- Lymphoma
Types of tumors that can be found in the colorectum
Adenocarcinoma and adenoma
2 other types of GI tumors that are not adenocarcinoma, SCC or lymphoma
- Neuroendocrine tumors/ carcinoid tumors
- Gastrointestinal stromal tumors
Define high grade dysplasia in Barrett esophagus (histology)
Very complex architecture with bridging:
- Absence of maturation of glandular mucosa
- Large, atypical, crowded and stratified nuclei
- Less cytoplasm
Define esophageal adenocarcinoma
Malignant tumor of glandular differentiation usually in the setting of Barrett esophagus
Usual location of esophageal adenocarcinoma and why
Distal esophagus since BE involves distal esophagus
Clinical manifestations of esophageal adenocarcinoma (5)
- Symptoms related to GERD
- Dysphagia
- Pain (epigastric, retrosternal)
- Weight loss
- Anemia
Describe the histological appearance of invasive adenocarcinoma
- Glands of various sizes and shapes infiltrating the stroma
- High N/C ratio
- Large irregular epithelial nuclei
- Clumped chromatin
Groups of people most commonly affected by esophageal squamous cell carcinoma
- >50 YO
- Men
3 risk factors for esophageal SCC
- Smoking
- Alcohol
- Carcinogens in food
3 clinical manifestations of esophageal SCC
Small tumors may be asymptomatic, however symptoms are:
- Dysphagia
- Chest pain
- Weight loss
Diagnostic method of choice for esophageal SCC
Endoscopy with biopsy
Usual location of esophageal SCC
Lower 2/3 of esophagus
Macroscopic features of esophageal SCC
- Tumor may be protruding into the lumen, show ulceration and cause stricture
- Beige and firm
- Uninvolved esophageal mucosa is normal (NOT associated with BE)
- Thickening of esophageal wall
- Narrowing of lumen
- Irregular surface