epithelial neoplasm

Microscopic Teaching (10/28) Epithelial Neoplasm (I) 2979 (21) Pleomorphic adenoma, parotid gland 3244 (42) Squamous cell carcinoma, esophagus 4203 (98) Basal cell carcinoma, lip

2979 (21) Pleomorphic adenoma, parotid gland • Tumor: (1) epithelial (2) mesenchymal (3) hematological (4) divergent differentiation • Pleomorphic adenoma (mixed tumor) (1)60% parotid gland tumors (2)often encapsulated (3)biphasic appearance: epithelial and mesenchymal differentiation (4)matrix: myxoid, hyaline, chondroid, osseous (5)epithelium: ducts, acini, tubules, strands, sheets

Well-defined tumor, with pushing growth border, and heterogeneous component

Well-defined tumor, with pushing growth border, and heterogeneous component

A little normal protid gland tissue can be seen.

A little normal protid gland tissue can be seen.

Mixed epithelial and mesenchymal differentiation.

matrix: myxoid, hyaline, chondroid, osseous

Epithelium: ducts, acini, tubules, strands, sheets

Epithelium: ductal cells and myoepithelial cells

Myoepithelial cells: clear, flattened, spindle shaped

Epithelium: ducts, acini, tubules, strands, sheets

matrix: myxoid, hyaline, chondroid, osseous

Mesenchymal components are modified myoepithelial cells.

3244 (42) Squamous cell carcinoma, esophagus • Anaplasia: (1) pleomorphism (2) abnormal nuclear morphology (3) mitoses (4) loss of polarity (5) tumor giant cells • SCC: partially recapitulate the normal organization of squamous epithelium

tumor

normal

(1) pleomorphism (2) abnormal nuclear morphology (3) mitoses (4) loss of polarity (5) tumor giant cells

Muscularis propria invasion

Adventitia invasion

Keratin pearls

Keratin pearls (角化珠)

mitoses

tumor giant cells

Single cell dyskeratosis

Single cell dyskeratosis

pleomorphism

Perineural invasion

Stromal desmoplasia

4203 (98) Basal cell carcinoma, lip • Most common skin cancers, on sunexposed skin • Slow growing • Nests of uniformly atypical basaloid cells with peripheral palisading • Stroma retracts away from the carcinoma: creating clefts • Tumor cells attemp to differentiate toward adnexal structures

Tumor nests in the dermis

Irregular tumor nests in the dermis

Connection with overlying squamous epithelium

Locally invasive growth

Locally invasive growth

Bright red trichohyaline granules, dystrophic calcification

Stroma retracts away from the carcinoma: creating clefts

Stroma retracts away from the carcinoma: creating clefts

Stroma retracts away from the carcinoma: creating clefts

Peripheral palisading: arranged radially with their long axis in parallel alignment

Melanin pigmentation

Normal follicular epithelium

BCC: follicular bulbar differentiation

Bright red trichohyaline granules