Tumor Pathology Review

Flashcards covering tumor types, definitions, sites, and microscopic features.

What is Basal Cell Carcinoma?

Locally malignant skin tumor from basal epidermis

Where are the common sites for Basal Cell Carcinoma?

Sun-exposed skin (face, especially near eyes, nose)

What are the microscopic features of Basal Cell Carcinoma?

Palisading basal cells at periphery, polyhedral central cells

What is a Giant Cell Tumor (Osteoclastoma)?

Tumor with giant cells and stromal cells

Where are the common sites for Giant Cell Tumor (Osteoclastoma)?

Around knee (distal femur, proximal tibia)

What are the microscopic features of Giant Cell Tumor (Osteoclastoma)?

Non-neoplastic multinucleated giant cells + neoplastic mononuclear stromal cells

What is an Adamantinoma?

Tumor with epithelial islands in fibrous stroma

Where are the common sites for Adamantinoma?

Jaw (ameloblastoma), tibia

What are the microscopic features of Adamantinoma?

Nests of odontogenic epithelium in fibrous stroma (jaw); unsettled epithelial origin in long bones

What is Squamous Cell Carcinoma?

Malignant tumor of squamous epithelium

Where are the common sites for Squamous Cell Carcinoma?

Skin, oral cavity, cervix, larynx, esophagus

What are the microscopic features of Squamous Cell Carcinoma?

Cell nests, keratin pearls, Broder’s grading (I-IV based on differentiation)

What is Adenocarcinoma?

Malignant tumor of glandular epithelium

Where are the common sites for Adenocarcinoma?

Glands (breast, prostate), GIT, endometrium

What are the microscopic features of Adenocarcinoma?

Acinar arrangement, pleomorphic cells, loss of basement membrane, mucin production, cystic/papillary forms

What is Mucinous Carcinoma?

Adenocarcinoma with mucin production

Where are the common sites for Mucinous Carcinoma?

GIT, gallbladder, breast, ovary

What are the microscopic features of Mucinous Carcinoma?

Mucinous pools (mucinous type) or signet ring cells (intracytoplasmic mucin)

What is Transitional Cell Carcinoma (TCC)?

Malignant tumor of transitional epithelium

Where are the common sites for Transitional Cell Carcinoma (TCC)?

Bladder, ureter, renal pelvis

What are the microscopic features of Transitional Cell Carcinoma (TCC)?

Papillary: malignant cells over vascular cores; Non-papillary: solid groups

What is Liposarcoma?

Malignant tumor of adipose tissue

Where are the common sites for Liposarcoma?

Retroperitoneum, mediastinum, intermuscular areas

What are the microscopic features of Liposarcoma?

Well-differentiated: lipoblasts; Poorly differentiated: pleomorphic, may have myxoid foci

What is Fibrosarcoma?

Malignant tumor of fibrous tissue

Where are the common sites for Fibrosarcoma?

Subcutaneous, intermuscular

What are the microscopic features of Fibrosarcoma?

Spindle cells with collagen (well differentiated), less collagen in anaplastic forms

What is Rhabdomyosarcoma?

Malignant tumor of striated muscle

Where are the common sites for Rhabdomyosarcoma?

Children: bladder, vagina; Adults: soft tissues

What are the microscopic features of Rhabdomyosarcoma?

Embryonal: spindle cells in myxoid matrix; Pleomorphic: strap cells; Alveolar: alveolar pattern

What is Leiomyosarcoma?

Malignant tumor of smooth muscle

Where are the common sites for Leiomyosarcoma?

Uterus, GIT

What are the microscopic features of Leiomyosarcoma?

Spindle cells, eosinophilic cytoplasm, large nuclei

What is Malignant Melanoma?

Tumor of melanocytes

Where are the common sites for Malignant Melanoma?

Skin, eyes, mucocutaneous junctions, meninges

What are the microscopic features of Malignant Melanoma?

Radial or vertical growth; atypical melanocytes, mitoses, pigment

What is Lipoma?

Benign tumor of fat cells

Where are the common sites for Lipoma?

Subcutaneous tissue (shoulder, neck, back), mesentery

What are the microscopic features of Lipoma?

Lobules of mature adipocytes separated by fibrovascular septa

What is Fibroma?

Benign fibrous tissue tumor

Where are the common sites for Fibroma?

Skin, ovary, GIT wall, bone

What are the microscopic features of Fibroma?

Spindle-shaped fibroblasts, collagen; may show hyaline or calcific changes

What is Chondroma?

Benign cartilage tumor

Where are the common sites for Chondroma?

Hands, feet (enchondroma), subperiosteal, soft tissues

What are the microscopic features of Chondroma?

Hyaline cartilage with chondrocytes in lacunae; possible calcification

What is Osteochondroma?

Bony-cartilaginous outgrowth (hamartoma)

Where are the common sites for Osteochondroma?

Long bones (near epiphyseal plate)

What are the microscopic features of Osteochondroma?

Bony stalk with cartilaginous cap

What is Osteoid Osteoma?

Small benign bone tumor producing osteoid

Where are the common sites for Osteoid Osteoma?

Cortex of femur, tibia

What are the microscopic features of Osteoid Osteoma?

Osteoid trabeculae rimmed by osteoblasts, vascular stroma

What is Compact Osteoma?

Dense ivory-like bone tumor

Where are the common sites for Compact Osteoma?

Skull, facial bones

What are the microscopic features of Compact Osteoma?

Concentric bone lamellae

What is Myxoma?

Rare tumor from primitive mesenchyme

Where are the common sites for Myxoma?

Heart (atrium), jaw

What are the microscopic features of Myxoma?

Stellate cells in mucoid matrix

What is Leiomyoma?

Benign tumor of smooth muscle

Where are the common sites for Leiomyoma?

Uterus (most common), GIT, bladder, skin

What are the microscopic features of Leiomyoma?

Interlacing smooth muscle bundles, eosinophilic cytoplasm, rod-like nuclei

What is Rhabdomyoma?

Rare tumor of striated muscle

Where are the common sites for Rhabdomyoma?

Heart (myocardium)

What are the microscopic features of Rhabdomyoma?

Striated muscle cells, stroma, vessels

What is Capillary Hemangioma?

Small blood vessel tumor

Where are the common sites for Capillary Hemangioma?

Face, lips, tongue, brain, kidney

What are the microscopic features of Capillary Hemangioma?

Small vascular spaces lined by endothelium

What is Cavernous Hemangioma?

Large blood-filled vascular spaces

Where are the common sites for Cavernous Hemangioma?

Face, tongue, liver, spleen, muscles

What are the microscopic features of Cavernous Hemangioma?

Large dilated blood-filled vessels lined by endothelium

What is Lymphangioma?

Lymphatic vessel malformation (hamartoma)

Where are the common sites for Lymphangioma?

Head, neck, axilla, lips, tongue, spleen

What are the microscopic features of Lymphangioma?

Wide lymphatic channels with pale lymph, fibrous stroma

What is Schwannoma?

Tumor of Schwann cells

Where are the common sites for Schwannoma?

Cranial and spinal nerves

What are the microscopic features of Schwannoma?

Antoni A: palisading Schwann cells; Antoni B: vacuolated cells

What is Neurofibroma?

Hamartomatous proliferation of nerve elements

Where are the common sites for Neurofibroma?

Skin, peripheral nerves

What are the microscopic features of Neurofibroma?

Mixed Schwann cells and nerve fibers in haphazard arrangement

What is Squamous Cell Papilloma?

From stratified squamous epithelium

Where are the common sites for Squamous Cell Papilloma?

Skin, oral mucosa, cervix, anal canal

What are the microscopic features of Squamous Cell Papilloma?

Stratified squamous epithelium with acanthosis and hyperkeratosis

What is Transitional Cell Papilloma?

From urothelium (premalignant)

Where are the common sites for Transitional Cell Papilloma?

UB, ureter, renal pelvis

What are the microscopic features of Transitional Cell Papilloma?

CT cores with transitional epithelium ≤6 layers

What is Duct Papilloma?

From duct epithelium

Where are the common sites for Duct Papilloma?

Major breast ducts

What are the microscopic features of Duct Papilloma?

Vascular cores with ductal epithelial cells

What is Mucous Cell Papilloma?

From glandular mucosa (adenomatous polyp)

Where are the common sites for Mucous Cell Papilloma?

GIT

What are the microscopic features of Mucous Cell Papilloma?

Columnar epithelium lining proliferated mucosal glands

What is Adenoma?

From glandular epithelium

Where are the common sites for Adenoma?

Glands (breast, ovary, GIT, etc.)

What are different types of Adenoma?

1. Simple (tubular) 2. Fibroadenoma 3. Cystadenoma 4. Papillary cystadenoma

What is a Lymphoma?

Malignant tumor of lymphocytes

Where are the common sites for a Lymphoma?

Lymph nodes, spleen, other sites

What are the microscopic features of a Lymphoma?

Atypical lymphocytes, architectural effacement

What is a Leukemia?

Malignant tumor of hematopoietic cells

Where are the common sites for a Leukemia?

Bone marrow, blood

What are the microscopic features of a Leukemia?

Abnormal blood counts, blasts

What is the microscopic feature of Acinar Arrangement?

Neoplastic cells arranged in gland-like structures