Chronic gastritis with Helicobacter Pylori

Chronic gastritis associated with infection with Helicobacter pylori.
Helicobacter pylori (blue bars, curved, 2 - 4 microns) rims in the mucus on the mucosa surface, at the intercellular lines. Photo : tangential section of the gastric mucosa. (Giemsa, ob. x40)

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Chronic peptic ulcer

Chronic peptic ulcer (stomach) is a mucosal defect which penetrates the muscularis mucosae and muscularis propria, produced by acid-pepsin aggression. Ulcer margins are perpendicular and present chronic gastritis. During the active phase, the base of the ulcer shows 4 zones : inflammatory exudate, fibrinoid necrosis, granulation tissue and fibrous tissue. The fibrous base of the ulcer may contain vessels with thickened wall or with thrombosis. (H&E, ob. x7)

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Chronic peptic ulcer (detail)

Chronic peptic ulcer (stomach). During the active phase, the base of the ulcer shows 4 zones :

inflammatory exudate - at the lumen (cell debris and neutrophils)

fibrinoid necrosis (yellow in van Gieson staining and pink in H&E)

granulation tissue (see Granulation tissue)

mature fibrous tissue (abundant collagen - red in van Gieson staining and pink in H&E, profound, spreading beneath ulcers margins, producing mucosal retraction - radiating folds). This fibrous layer may contain vessels with thickened walls or with thrombosis. (H&E, ob. x10)

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Gastric carcinoma, intestinal type

Gastric adenocarcinoma is a malignant epithelial tumor, originating from glandular epithelium of the gastric mucosa. According to Lauren classification, gastric adenocarcinoma may be: intestinal type, diffuse type and mixed type.

Gastric adenocarcinoma, intestinal type. Tumor cells describe irregular tubular structures, with stratification, multiple lumens surrounded by a reduced stroma ("back to back" aspect). The tumor invades the gastric wall, infiltrating the muscularis mucosae, the submucosa and thence the muscularis propria. Often it associates intestinal metaplasia in adjacent mucosa. Depending on glandular architecture, cellular pleomorphism and mucosecretion, adenocarcinoma may present 3 degrees of differentiation : well (photo), moderate and poorly differentiate. (H&E, ob. x10)

Gastric adenocarcinoma, intestinal type, infiltrating muscularis propria. (H&E, ob. x10)

Gastric adenocarcinoma, intestinal type. (H&E, ob. X40)

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Gastric carcinoma, diffuse type (mucinous)

Gastric adenocarcinoma is a malignant epithelial tumor, originating from glandular epithelium of the gastric mucosa. According to Lauren classification, gastric adenocarcinoma may be: intestinal type, diffuse type and mixed type.

Gastric adenocarcinoma, diffuse (infiltrative) type. Tumor cells are discohesive and secrete mucus which is delivered in the interstitium producing large pools of mucus/colloid (optically "empty" spaces) - mucinous (colloid) adenocarcinoma, poorly differentiated (Lauren classification). If the mucus remains inside the tumor cell, it pushes the nucleus against the cell membrane - "signet-ring cell". (H&E, ob. x10)

Gastric carcinoma, diffuse type (mucinous) - detail

Gastric adenocarcinoma, diffuse type. (H&E, ob. X20)

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Colon

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Adenomatous tubulo-villous polyp, pedunculated (colon)

Adenoma is a benign epithelial tumor arising in epithelium of mucosa (stomach, small intestine and bowel), glands (endocrine and exocrine) and ducts. In hollow organs (e.g. digestive tract) the adenoma grows upwards into the lumen - adenomatous polyp or polypoid adenoma. Depending on the type of the insertion base, adenoma may be pedunculated (lobular head with a long, slender stalk, covered by normal mucosa - see photo) or sessile (broad base). If not elevated above the surface of the mucosa, the adenoma is called flat adenoma.

Adenomatous tubulo-villous polyp, pedunculated (colon). The adenomatous proliferation is characterized by different degrees of cell dysplasia (cellular and architectural atypia) : loss of normal differentiation of epithelium, irregular cells with hyperchromatic nuclei, (pseudo)stratified nuclei, nucleolus, decreased mucosecretion and mitosis. The architecture may be tubular, villous or tubulo-villous. Basement membrane and muscularis mucosae are intact. (HE, ob. x4)

Detail of an adenomatous tubulo-villous polyp (colon)

Compared to normal colonic epithelium (lower left corner of the picture) the adenomatous proliferation is characterized by different degrees of cell dysplasia and tubular, villous or tubulo-villous architecture. In tubular component tumor cells proliferate generating tubular shapes, more or less irregular or branched. The villous pattern presents villi - finger-like projections lined by dysplastic epithelium and with thin fibro-vascular core. Passage from tumoral epithelium to normal mucosa is abrupt. (HE, ob. x10)

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Adenomatous villous polyp, sessile (colon)

Adenoma is a benign epithelial tumor arising in epithelium of mucosa (stomach, small intestine and bowel), glands (endocrine and exocrine) and ducts.

In hollow organs (e.g. digestive tract) the adenoma grows upwards into the lumen - adenomatous polyp or polypoid adenoma. Depending on the type of the insertion base, adenoma may be pedunculated (lobular head with a long, slender stalk, covered by normal mucosa) or sessile (broad base - see photo). If not elevated above the surface of the mucosa, the adenoma is called flat adenoma.

Adenomatous villous polyp, sessile (colon). The adenomatous proliferation is characterized by different degrees of cell dysplasia (cellular and architectural atypia) : loss of normal differentiation of epithelium, irregular cells with hyperchromatic nuclei, (pseudo)stratified nuclei, nucleolus, decreased mucosecretion and atypical mitosis. The architecture may be tubular, villous (photo) or tubulo-villous. Basement membrane and muscularis mucosae are intact. (HE, ob. x4)

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Moderately differentiated adenocarcinoma (colon)

Adenocarcinoma is a malignant epithelial tumor, originating from glandular epithelium of the colorectal mucosa. It invades the wall, infiltrating the muscularis mucosae, the submucosa (photo) and thence the muscularis propria. (Notice the end-point of muscularis mucosae. At left from this point, muscularis mucosae is continuous. At right from this point, muscularis mucosae is destroyed by tumor cells invasion.) Tumor cells describe irregular tubular structures, harboring stratification, multiple lumens, reduced stroma ("back to back" aspect). Depending on glandular architecture, cellular pleomorphism and mucosecretion of the predominant pattern, adenocarcinoma may present 3 degrees of differentiation: well, moderate and poorly differentiate. (H&E, ob. x10)

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Poorly differentiated adenocarcinoma (mucinous), colon

Adenocarcinoma is a malignant epithelial tumor, originating from glandular epithelium of the colorectal mucosa. It invades the wall, infiltrating the muscularis mucosae, the submucosa and thence the muscularis propria. Tumor cells are discohesive and secrete mucus which invades the interstitium producing large pools of mucus/colloid (optically "empty" spaces) - mucinous (colloid) adenocarcinoma, poorly differentiated. If the mucus remains inside the tumor cell, it pushes the nucleus at the periphery, against the cell membrane - "signet-ring cell". (H&E, ob. x20)

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