12/13 - Intro to Neoplasia & Diagnostic Methods Flashcards
Define Neoplasia?
Abnormal new growth - the growth of which exceeds and is uncoordinated with that of normal tissue and persists in the same excessive manner after cessastion of stimuli that evoked it.
What does tumor mean? What is it used interchangeably? What is a common misconception?
Originally meant “swelling” - now often used interchangably with neoplasia.
Tumor does NOT = cancer
Neoplasia does NOT = cancer
Define anaplasia? What is metastasis?
Anaplasia: lack of differentiation
Metastasis: growth at a distant site
Below are the six different major cells that can give rise to tumors. What is the name of a tumor whos origin is:
- Epithelial
- Mesenchymal
- Hematolymphoid
- Melanocytic
- CNS
- epithelial - carcinoma
- mesenchymal - sarcoma
- hematolymphoic - lymphoma, leukemia
- melanocytic - melanoma
- CNS - clioma, schwanoma
What three characteristics are used to classify tumors?
- Cell of origin (where it’s derived from): epithelial, mesenchymal, etc.
- Differntiation: appearance under the microscope: well, moderately, poor
- Behavior: benign or malignant
What are the three types of epithelia? What is the function of each?What is an important landmark?
- Simple squamous: protective/barrier function
- Simple cuboidal: covers many organs
- Simple columnar ciliated: lines intestines, lines places where you want to bring stuff into the bloodstream
Important landmark is the basal lamina
What is the name for glands that give rise to cancer?
Adeno - meaning “derived from glands”
Tumors of epithelial origin have what common features? What are they called when they are benign vs. maligneant? How can they be further classified?
Typically arise from ectoderm or endoderm germ layers
Benign: “oma” (exp. colonic adenoma)
Malignant: “carcinoma” (exp: adenocarcinoma)
Further classified by architecture: papillary, villous, sessile (flat and deep), cystic
What is the difference btween carcinoma and sarcoma?
Carcinoma - cancer of the epithelium
Sarcoma - cancer of mesenchymal origin (lamina propria)
What types of cells arise from the mesodermal germ layer?
Fibroblasts
Adipocytes
Smooth muscle
Skeletal muscle
Bone
Cartilage
Blood
What is the nomenclature (benign, malignant) for the following cells dervied from the mesodermal germ layer?
- Fibroblasts
- Adipocytes
- Smooth muscle
Fibroblasts: fibroma, fibrosarcoma
Adipocytes: lipoma, liposarcoma
Smooth muscle: leiomyoma, leiomyosarcoma
What is the nomenclature (benign, malignant) for the following cells dervied from the mesodermal germ layer?
- Skeletal muscle
- Bone
- Cartilage
- Blood
Skeletal muscle: rhabdomyoma, rhabdomyosarcoma
Bone: osteoma, osteosarcoma
Cartilage: chondroma, chondrosarcoma
Blood: hemangioma, angiosarcoma
What are the three types of hematolymphoid neoplasms?
- Lymphoid neoplasms
- Myeloid neoplasms
- Histiocytic neoplasms
What is the pathogenesis of the following neoplasms of hematolymphoid origin?:
- Lymphoid neoplasms
- Myeloid neoplasms
- Histiocytic neoplasms
- Lymphoid neoplasms: cell resembles normal stage of lymphocyte differentiaiton (non-hodgkin lymphomas, hodgkin lymphoma)
- Myeloid neoplasms: arise from progenitor cells that give rise to granulocytes, RBCs, and platelets (acute myeloid leukemia)
- Histiocytic neoplasms: proliferative lesions of macrophages and dendritic cells (langerhans cell histiocytosis)
What is the origin of melanocytes? What are they called when they’re benign vs malignant? How does their appearance differ?
Neural crest origin
Benign: nevus - homogenous in color with a defined border
Malignant: melanoma - hyperpigmented areas with light areas nearby, irregular border
What is the different in appearance, growth rate, and invasivity of benign (tumor) vs. malignant (cancer) neoplasms?
Benign (tumor):
- “oma”
- resembles normal tissue but often larger than normal tissue
- Slow growth rate
- non-invasive, encapsulated
- does NOT metastasize
Malignant (cancer):
- “carcinomas” or “sarcomas”
- variable morphology
- variable growth rate
- Invasive growth pattern (non-encapsulated)
- Capable of metastasizing (may now, but CAN)
What is often seen on histology of a malignant tissue?
Irregular pattern, cells grow in different orientations.
Presence of atypical mitotic figures.
What are characteristics are used to determine if something is benign vs. malignant?
Differentiation and anaplasia
Rate of growth
Local invasion (malig)
Mets (malig)
Define “differentiation and anaplasia” and how it pertains to determining whether tumor histology is normal or malignant?
Extent to which tumor cells morphologically and functionally resemble the normal tissue counterpart.
Benign tumors are almost always well-differentiated (looks like normal tissue counterpart)
Malignant tumors vary from well to poorly differentiated/anaplastic
What are characteristics of well-differentiated tissues?
Resemble normal histology
Evidence of maturation
Evidence of functionality
What are some histological features that are associated with malignancy?
- Cellular and nuclear pleomorphism (cells at different stages)
- Coarsely clumped chromatin
- Hyperchromatic nuclei
- High nuclear to cytoplasmic ratio (N/C ratio) (normal nuclei are all same-ish size- in malig. nucleus is bigger)
- Large nucleioli
- Atypical, bizarre mitosises (mitotic figures)
- Loss of tissue polarity
- Tumor giant cells
How can you tell that this is a picture of a malignancy?
Nuclear pleomorphism: HUGE nuclei with a ton of chromatin packed along the nuclear membrane
Nuclei with coarsely clumped chromatin.
What leads you to believe that this tissue is malignant?
High nucleus/cytoplasm ratio (large nucleus)
Large nucleoli
What is displayed in this picture? How do these occur?
Nuclear pleomorphism with tumor giant cells
Can happen because of cells continuing to divide without cytokinesis or by cell fusion.
What is tissue polarity? What occurs with in malignant tissue?
When nuclei line up, basal orientation, apical cytoplasm (ie you can tell the top from the bottom).
Malignant tissue: loss of polarity (see image), nuclei off of the basal lamina, hyperchromatic cells. Cells undergoing mitosis/apoptosis.