Chapter 7 Part 1 Flashcards
Cancer
generic term for all malignant neoplasms
Neoplasia
new growth resulting from genetic alterations passed down to progeny of tumor cells
Growth pattern of neoplasm
excessive, unregulated proliferation that becomes autonomous
Tumor
initially used to describe inflammation, often used as a synonym for neoplasia
Oncology
study of tumors
Clonal
entire population of neoplasm arises from single cell that has incurred genetic change
Benign
tumors considered to be grossly and microscopically innocent; localized, amenable to local surgical removal
Malignant
invade and destroy adjacent structures and spread to distant sites to cause death
-oma tissue derivation
benign tumor arising from specific tissue (indicated by first portion of the word)
carcinoma tissue derivation
epithelial origin from any 3 germ layers
sarcoma tissue derivation
mesenchymal derivation
tumor characteristics of benign neoplasms
well differentiated, usually progressive and slowly growing, well-demarcated mass, non-metastatic
tumor characteristics of malignant neoplasms
lack of differentiation, atypical structure, erratic and varied growth, locally invasive, infiltrating surrounding tissue, frequently metastasizes
Polyp
macroscopically visible projection into a lumen
adenoma
benign epithelial neoplasm derived from glandular tissue
Malignant neoplasms with benign terminology
mesothelioma, seminoma, etc.
contents of a mixed salivary tumor
epithelial components with myxoid stroma (pleomorphic adenoma)
Tissue components of benign and malignant neoplasms
neoplastic parenchyma and reactive stroma
cystic teratoma of ovary
originates from totipotential germ cells, cystic tumor lined by skin with hair, sebaceous glands, tooth structures
Tumor differentiation
extent to which neoplastic parenchymal cells resemble corresponding normal cells
Major determinants of differentiation
neoplastic nuclei and cytoplasm, architectural relationship to other cells
“well differentiated” measure
closely resembles parent tissue
“moderately differentiated” measure
features of original tissue are identifiable but not the dominant pattern
“poorly differentiated” measure
small minority of cellular constituents allow identification of parent tissue
“undifferentiated” measure
tissue of origin cannot be discerned by histopathologic appearance
Why are benign tumors generally considered well differentiated?
neoplastic cells so closely resemble parent tissue it may be impossible to recognize the neoplastic nature of the lesion, mitoses are rare and are of normal configuration
Anaplasia
lack of differentiation, considered a hallmark of malignancy
Metaplasia
replacement of one type of cell with another type
Dysplasia
disordered growth, pleomorphic, architecturally deranged
Dysplasia in squamous epithelia
normal progressive maturation of cells fails, full thickness replacement of epithelium by basal appearing hyperchromatic nuclei
Carcinoma in situ
marked dysplastic, full thickness epithelium changes that do not breach the basement membrane
common histopathologic features used to assess rate of growth
mitotic figures, loss of polarity, pleomorphism, abnormal nuclear morphology
One unequivocal criterion of malignancy
metastasis, spread of tumor to physically discontinuous with primary tumor
Clinical differences between solid and hematopoietic tumors
lymphomas and leukemias are often disseminated at time of diagnosis and, therefore, are less likely to be cleared
