Neoplasia Flashcards
Describe cancer.
-neoplastic disease that is fatal
-invasion & metastasis
-highly anaplastic
-carcinoma & sarcoma
Describe neoplasia VS neoplasm.
- Neoplasia
-formation of neoplasm - Neoplasms
-new & abnormal growth
-uncontrolled & progressive
-tumor
-irreversible autonomous prolif
-indolent = benign (-oma)
-aggressive = malignant (sarcoma, or carcinoma)
*benign sounding BUT malignant neoplasm: lymphoma, melanoma, mesothelioma, seminoma
Describe hamartoma VS choristoma.
tumor like lesions
1. Hamartoma
-disorganized but benign masses composed of cells indigenous to involved tissue w blood vessels, has mutations, considered neoplasm
2. Choristoma
-heterotopic rest of cells
-ex dermoid or normal adrenal gland tissue on surface of liver
Describe parenchymal cells.
tumor types
1. Epithelial cells
-most organs, epi, mucosa, glands
-endoderm, ectoderm, mesoderm derived
-squamous, cuboidal, columnar
-cell junction, tightly packed, little intercellular matrix
-polarized (apical VS basal ends of cells are different)
2. Mesenchymal cells
-CT, muscle, endothelial cells, BM, blood
-mesoderm derived
-round to spindle shaped, scant cytoplasm
-widely sep by lots of intracellular matrix, streams, bundles
Describe nomenclature of neoplasm.
MDx:
Location of neoplasm (organ) + prefix to designate tissue of origin + suffix to designate tissue of origin + suffix to designate growth behavior (indolent VS aggressive)
undifferentiated or anaplastic neoplasms
Describe adenoma VS papilloma VS polyp.
benign epi tumors
1. Adenoma
-tumor arising from grandular epithelium (ex. Sebaceous gland) or tumor derived from non glandular epithelial tissue that exhibits tubular pattern
2. Papilloma
-benign, exophytic (growing outward), growing from cutaneous or mucocutaneous surface
3. Polyp
-grossly visible, benign epi tumor projecting from mucosal surface (SI)
Describe soft tissue tumors.
-perivascular wall tumors, nerve sheath tumors, fibrosarcoma, myxosarcoma, leiomyosarcoma, liposarcoma, rhabdomyosarcoma, unclassified spindle cell tumor/sarcoma arising in dermis or subcutis
Describe neoplasms with specialized names.
- Lymphoma or lymphosarcoma
-always malignant
-cells of hematopoietic system are mesenchymal - Teratoma
-tumor derived from cells representing all 3 embryo germ layers
-present in gonads
-benign
-ex: ovarian teratoma contain skin, bone, neural tissue - Mast cell tumor
-low/high grade
-grade I,II,III - Leukemia
-tumor arising from neoplastic cells of BM & circ in blood - Multiple myeloma
-malignant tumor of plasma cells - Melanocytoma (benign)
-can be malignant melanoma
-tumor arising from melanocytes
Describe the cell criteria of malignancy.
-differentiation
>extent to which tumor cells resemble normal parenchymal cells (morphologically & functionally)
>well differentiated = resemble tissue of origin
>poorly differentiated = barely resemble tissue of origin
Describe differentiation of neoplastic cells.
Describe tumor characteristics.
-tumors arise from any normal tissue
-benign tumor = mass that dont invade surrounding tissue or spread
-malignant tumor = locally invasive & can metastasize
1. Loss of differentiation = morphologic variability in tumor cells, abnormal tissue architecture, loss of specialized cell function
2. Unlimited proliferative potentional = cont cell division & resistance to cell death
*tumor grade (degree of differentiation) & stage (extent of spread) = est prognosis & treatment options
Describe the cellular criteria of malignancy.
-anaplasia in malignant neoplasm:
>pleomorphic
>anisokaryosis/anisocytosis
>nuclear hyperchromasia
>high N:C ratio
>prominent/multiple nucleoli
>multiple nuclei
>abnormal mitotic figures
Describe the biology solid tumor growth.
- Latent period
-time before tumor becomes clin detectable - Smallest clinic detectable mass
-1cm (1g in weight)
-10^9 cells
Describe stepwise tumor development.
Initiated cells have irreversible genetic damage -> presence of promoter the cells expand to pre neoplastic lesion or benign tumor -> genetic & epi genetic alterations -> malignant tumor from sub clone of cells within the benign precursor lesion
Describe mitotic count.
Vet cancer guidelines & protocols
-provide standard methods
-eval neoplasm in animals & accrue data -> lg data sets w comparable info eval & studied validated uniformly
-meaningful conclusions
-accurate prognostic info that will improve patient care
Describe mitotic figures.
-certain phases of mitosis are histologically mitotic figures
Describe the limitations of mitotic count.
-counting mitosis per HPF is imprecise bc too much variation-
-MC close to clin est cut offs - determined by type of neoplasm being assessed
-specimens size smaller than 2.37mm^2
-lg specimens w multiple sections
-specimens w numerous spaces - vascular, ducts, acini, desmoplasia, tumor, matrix, necrosis
Describe MC VS MI.
- MI
-# cells undergoing mitosis divided by # cells not undergoing mitosis
-have to count cells NOT in mitosis!!! *
-determined in histologic sections, cell suspensions, reported as percentage or # per 1000 cells or vol of cells - MC
-# of mitotic figures in a given area
Describe neoplastic transformation.
- Initiation
-irreversible alteration of genetic material - Promotion
-selective outgrowth of initiated cells to form benign tumor - Progression
-gradual development of features of malignancy due to combo of genetic & epigenetic change
Describe the gross features of neoplasia.
-something added - organ enlargement or mass lesion
-shape: nodular, polypoid/papillary, pedunculated, cystic/cavitary, umbilicated (depressed center) indicates rapid growth
-color change: depending on cell type accumulating
-firmness: sarcomas or induction of tumor stroma in other types of neoplasms
>scirrhous response carcinoma (desmoplasia) = multiple nodules or bands of fibrous CT in response to epi neoplasm
-demarcation MDx = hepatic lymphoma
More examples of gross neoplasia.
