Cancerous and Precancerous Histopathology Laboratory

Colon

Desmoplasia (Colon)

Colon

Infiltrative edge (Colon)

Colon

Tumor Buds (Colon)

Colon

Colorectal adenocarcinoma (Colon)

Colon

Mucinous differentiation (Colon)

Colon

TILs (tumor-infiltrating lymphocytes, Colon)

Colon

Tumor Budding (Colon)

Colon

Acute perivisceral inflammation (Colon)

Colon

"Dirty necrosis" (Colon)

Colon

Desmoplasia (Colon)

Colon

Mucinous differentiation (Colon)

Colon

The tumor infiltrates through the muscularis propria into the pericolorectal/pericolic adipose tissue. (Colon)

* My note - the arrow actually points at desmoplasia, the infiltration is seen around it on the left and right fields

Stomach

Lymphovascular invasion (Stomach)

Stomach

Muscolaris Mucoase (Stomach)

Stomach

Gastric Mucosa (Stomach)

Stomach

Submucosae (Stomach)

Stomach

Lymphovascular invasion (Stomach)

Stomach

Gastric ulcer (Stomach)

Stomach

Gastric dysplasia (Stomach)

Stomach

Infiltrating adenocarcinoma (Stomach)

Breast

Fibroadenoma (Breast)

Breast

Normal lipoinvoluted breast gland parenchyma (Breast)

Breast

Adipose tissue (Breast)

Breast

invasive breast carcinoma (IBC) of no special type (NST)

(Breast)

Breast

Necrosis + Calcification - Comedonic Carcinoma (Breast)

breast

TILs (Breast)

Breast

In situ carcinoma with necrosis in breast carcinoma (Breast)

Breast

Striated muscle (Breast)

Breast

Mamma ducts (Breast)

Breast

Mitosis (Breast)

Kidney

Kidney cancer - Vessels

Network of arborizing(branching) small, thin walled vessels (important diagnostic feature for cases with granular eosinophilic cytoplasm)

(Kidney)

*My note - this is "chicken wire" pattern, we see many vessels bc tumors are highly vascularized.

Kidney

Kidney cancer - Cells

Nests of large cells with cleared out and vacuolated cytoplasm and nuclear atypia.

(Kidney)

*My note - this is Clear Cell Renal Cell Carcinoma (ccRCC), the most common type of kidney cancer.

Clear cell carcinoma is called “clear cell” because the tumor cells contain lipid-rich cytoplasm, which becomes clear during histological processing.

Kidney

Kidney cancer - Architectural patterns

Architectural patterns: solid, alveolar (nested), acinar (tubular), microcystic (containing extravasated red blood cells or eosinophilic fluid) and occasionally macrocystic

(Kidney)

* My note - Architectural Diversity: The cells assemble into organized geometric configurations. These present as alveolar nests, gland-like acini (tubules), solid sheets, or fluid-filled microcysts.

Kidney

Kidney cancer - Membrane

Typically compact nests and sheets of cells with clear cytoplasm and distinct membrane

(Kidney)

* My note - Distinct Membrane: The thick, dark pink boundaries create a rigid perimeter around each cell. This mimics a plant cell or a crisp "honeycomb" network.

Pancreas

Invasive PDAC (Pancreatic Ductal Adenocarcinoma)

Moderately differentiated adenocarcinoma. Foci of smaller and more irregular glands and some individual pleomorphic cells are often found at the tumour margins. Common to both well-differentiated and moderately differentiated carcinomas is a desmoplastic stroma that encompasses the neoplastic glands, sometimes in a ductocentric pattern.

(Pancreas)

Pancreas

Desmoplastic stroma

The stroma is one of the most important histological features.

In pancreatic ductal adenocarcinoma, the tumor glands are often embedded in abundant dense fibrous tissue.

This desmoplastic stroma contains fibroblasts, inflammatory cells, extracellular matrix, and blood vessels.

It is not just a passive background. It actively interacts with tumor cells and contributes to tumor progression, invasion, and resistance to therapy.

 

For students, the simple idea is: pancreatic ductal adenocarcinoma is often a tumor made of irregular malignant glands in a dense fibrotic stroma.

(Pancreas)

Pancreas

Cytological features

The neoplastic glands are lined by atypical epithelial cells.

The cells may show:

- enlarged nuclei

- irregular nuclear membranes,

- hyperchromasia

- prominent nucleoli

- loss of polarity (of nucleus)

- mitotic figures

- foamy cytoplasm.

 

The degree of atypia can vary. Some tumors are well differentiated and form recognizable glands. Others are poorly differentiated and may form solid nests or single infiltrating cells.

(Pancreas)

Pancreas

Lymph node

(Pancreas)

Pancreas

Lymphnode metastasis

(Pancreas)

*My note - large, irregular, open white spaces lined by atypical, dark purple epithelial cells.

Pancreas

Duodenum

The duodenum—the first section of the small intestine—features the four standard gastrointestinal layers: mucosa, submucosa, muscularis externa, and adventitia. Its defining histological characteristic is the presence of Brunner's glands in the submucosa, which secrete alkaline mucus to neutralize acidic stomach chyme.

Pancreas

Pancreatic Parenchyma

(Pancreas)

*My note - The pancreatic parenchyma is a compound tubuloacinar gland that consists of two distinct functional units: the exocrine component, which makes up about 98-99% of the tissue, and the endocrine component, which forms scattered clusters throughout. It is enclosed by a thin connective tissue capsule that sends septa into the organ, dividing it into functional lobules.

Pancreas

Intrapancreatic biliary duct

(Pancreas)

Pancreas

Pleomorphic cells

(Pancreas)

* My note - The red arrow points directly to a large, atypical pleomorphic cell nucleus.

What you see: This nucleus is significantly larger, darker (hyperchromatic), and more irregularly shaped than the small, uniform, round nuclei of the surrounding background lymphocytes.

Significance: Pleomorphism represents a high degree of variation in nuclear size and shape, which is a core histological hallmark of malignancy.

Pancreas

Vascular invasion

(Pancreas)

Pancreas

Islets of Langerhans

The islets of Langerhans represent the endocrine part of the pancreas. The cells are lighter than those of the pancreatic acini. Depending on the cell type, they secrete certain hormones into surrounding fenestrated capillaries. Beta cells (70%): Insulin Alpha cells (20%): Glucagon Delta cells (5%): Somatostatin PP cells (2%): Pancreatic polypeptide.

(Pancreas)

Pancreas

Pancreatic duct (big lumen)

(Pancreas)

* My note - the small lumen are probably interlobular ducts.

Pancreas

Pancreatic duct (duct of Wirsung)

(Pancreas)

Lung

Lymphnode with marked antracosis

(Lung)

Lung

Main broncus

Primary Bronchi

Respiratory Epithelium - composed of a pseudostratified columnar epithelium.

Basement Membrane - thick, eosinophilic band beneath the epithelium.

Lamina Propria - dense irregular connective tissue.

Bronchial Cartilage 

Peri-bronchiolar Glands

Smooth Muscle

(Lung)

Lung

Primary (Muscular) Bronchioles

Epithelium changes from pseudostratified columnar to simple, ciliated columnar epithelium as they decrease in diameter.

Club Cells - dome-shaped secretory cells.

Smooth Muscle - variable amounts present.

(Lung)

Lung

Neoplastic Papillae - Papillary growth pattern

This tumour consists of neoplastic glandular cells growing along the surface of fibrovascular cores

(Lung)

Lung

Micropapillae

Micropapillary architecture within the airspaces, without fibrovascular core.

(Lung)

Lung

STAS

Spread through airspaces in adenocarcinoma

Many airspace clusters of tumour cells spread far beyond the tumour edge in a continuous manner , forming the lesion of spread through airspaces

(Lung)

Lung

Lymphovascular invasion

(Lung)

Lung

Antracosis

(Lung)

Lung

Secondary bronchus

(Lung)

Lung

Artery

(Lung)

Lung

Vein

(Lung)

Thyroid

Nuclear features in PTC (Papillary Thyroid Carcinoma)

Change of nuclear size and shape, nuclear enlargement, elongation and overlapping. - Chromatin characteristics: chromatin clearing / optically clear chromatin, chromatin margination, glassy / ground glass nuclei, Orphan Annie eye (transparent) nuclei - Nuclear membrane irregularity: irregular nuclear contour, nuclear grooves and nuclear pseudoinclusions (represent cytoplasmic invaginations).

(Thyroid)

Thyroid

Psammoma Body

Psammoma bodies defined as laminated microcalcification are frequently associated with classic, tall cell, hobnail variants; it is postulated that psammoma bodies are formed in the hyalinized core / stalk of papillae.

(Thyroid)

Thyroid

Colloid

Follicular cells normally synthesize thyroglobulin and secrete it into follicular lumen

Thyroid peroxidase, found in apical membrane of thyroid follicular cells, catalyzes iodination of tyrosine residues on thyroglobulin molecule and coupling of iodotyrosyl residues to form T4 (thyroxine) and T3, which are still bound to thyroglobulin, making them inactive; they are then stored as colloid.

In response to TSH, follicular cells pinocytose colloid, release the thyroglobulin, and secrete now active T4 and T3 into bloodstream

(Thyroid)

Thyroid

Normal thyroid follicules

Normal thyroid follicules are lined by a flat/ cuboidal epithelium. Its function is the production and secretion (into the blood) of thyroid homones.

(Thyroid)

Thyroid

Papillary modification in benign hyperfunctioning nodule

In an hyperfunction setting, some hyperplastic thyroid nodules may exhibit papillary structures, named Sanderson polsters. They lack the typical cytological atypia and features of PTC.

(Thyroid)

Thyroid

Parafollicular C Cells

C cells represent 0.1% of gland, produce calcitonin.

(Thyroid)

Thyroid

Invasive front in PTC

PTC usually shows infiltrative borders, which represent a key morphological feature distinguishing it from thyroid follicular adenoma, which is typically encapsulated.

(Thyroid)

Thyroid

Psammoma bodies interstitial spaces

Psammoma bodies in interstitial soaces may represent a sign of lymphatic invasion.

(Thyroid)

Prostate

Infiltrative growth pattern

The infiltrative growth pattern typically consists of small atypical glands scattered between larger, more complex, and frequently paler benign glands.

(Prostate)

Prostate

Crowded glands

The presence of crowded glands in a linear arrangement spanning the width of the biopsy core should raise concern for malignancy. Single cells, cells arranged in cords, and fused and cribriform glands are less common patterns of invasion that are characteristic of high-grade prostatic carcinoma.

(Prostate)

Prostate

Prominent nucleoli

Prominent nucleoli are a common finding in prostate cancer; nuclear enlargement is often a helpful criterion, but its diagnostic value is not as high as that of the presence of prominent nucleoli.

(Prostate)

Prostate

Nerve

(Prostate)

Prostate

Glomerulations

they are a feature of prostate adenocarcinoma and are not seen in benign mimics. They are characterized by dilated glands containing intraluminal structures, which have a single point of attachment and which resemble renal glomeruli.

(Prostate)

Prostate

Prostatic urethra

(Prostate)

Skin

UV damage

Exposure to UV radiations damages the DNA in skin cells, triggering mutations (C>T substitutions) that cause melanocytes—the pigment-producing cells—to proliferate "without control", infiltrate, and metastatize

(Skin)

Skin

Epithelioid melanocytes

(Skin)

Skin

Mitosis

(Skin)

Skin

Mitosis

(Skin)

Skin

Mitosis

(Skin)

Skin

Deep infiltration (hypodermis)

(Skin)

Skin

Micro-satellitosis

(Skin)

Skin

Lympho-vascular invasion

(Skin)

Skin

Upper pin - Adjacent epidermis

Lower pin - Papillary dermis

(Skin)

Skin

Reticular dermis

(Skin)

Skin

Hypodermis

(Skin)

Skin

Adnexal structure

(Skin)

Skin

Radial growth phase

(Skin)

Skin

Vertical growth phase

(Skin)

Skin

Epidermal effacement

(Skin)

Skin

Melanin pigment

(Skin)

Skin

Ulceration

(Skin)

Skin

TILs

(Skin)

Urothelial tract

Renal glomerulus

(Urothelial tract)

Urothelial tract

Lymph vascular invasion

(Urothelial tract)

Urothelial tract

Necrosis

(Urothelial tract)

Urothelial tract

High Grade component

(Urothelial tract)

Urothelial tract

Invasion of renal parenchyma

T3 (Renal pelvis) Tumour invades beyond muscularis into peripelvic fat or renal parenchyma

(Urothelial tract)

Urothelial tract

Peripelvic Fat

(Urothelial tract)

Urothelial tract

Ureter

(Urothelial tract)