WK5 - Pathology of Neoplasia Flashcards
What is a tumor?
= swelling or lump
= neoplasm
What is neoplasm?
- abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the adjacent normal tissues
- the mass persists in the same excessive manner even after the stimulus or cause is removed
- neoplasms are named according to the type of normal tissue they most closely resemble
- neoplasm may be benign or malignant
What is cancer?
- generic term for malignant neoplasms of all types
- cancers of different organs are different diseases
- they have a different etiology, pathology, clinical behavior and treatment
- cancers that spreads from one organ to another (metastasis) retains the biological characteristics of its primary cancer
What is hypertrophy?
- an increase in the size of cells within an organ
- occurs in response to a stimulus
- when the stimulus is removed, the cells return to normal size
Ex. bodybuilding
What is hyperplasia?
- refers to an abnormal increase in cellular quantity
- hyperplastic growth in cell number usually results in organ enlargement or (benign) tumor formation
- may be due to a number of causes such as increased stress, chronic inflammatory response, or compensation for damage, etc.
What is dysplasia?
- a pre-malignant change in cells (usually epithelium) characterized by disordered growth and morphologic changes in the cell nucleus
Is there a difference between hyperplasia and dysplasia?
- hyperplasia cells are normal and usually benign
- dysplasia cells are not normal and are pre-cancer
What is high grade dysplasia?
- synonymous with carcinoma-in-situ
- high-grade dysplasia has most of the cellular morphologic changes of cancer cells but is not invasive and cannot therefore metastasize
- by molecular analysis high-grade dysplasia has fewer mutations than invasive cancer
What is atrophy?
- a reduction in either the size of cells or the number of cells within an organ
- this process is reversible when it represents part of a response to an external stimulus or it can be part of the normal aging process
Is hypertrophy identical to hyperplasia?
hypertrophy is increase in size of cells within an organ while hyperplasia is increase in number of cells within an organ
What is the composition of neoplasm?
- proliferating neoplastic cells that consitute the parenchyma
- supportive stroma made up of connective tissue and blood vessels. the stroma is not neoplastic. it is derived from normal host tissues that the tumor recruits for its own use
- when large quantities of fibrous tissue are present in the supporting stroma the tumor is said to be scirrhous or desmoplastic and clinically the tumor is firm and shrunken
Describe benign neoplasm.
- slow growing
- usually circumscribed
- a mass that pushes aside adjacent tissues
- does not infiltrate adjacent tissues
- do not metastasize
- histologically resemble the tissue of origin
- good prognosis
- can be cured by surgical removal
- can be a precursor for malignant neoplasm
Describe malignant neoplasm.
- grow rapidly
- poorly circumscribed
- infiltrate and destroy adjacent tissues
- metastasize
- histologically may poorly resemble tissue of origin
- often fatal
- surgically cured only in the early stages
How does malignant neoplasm grow/spread?
- direct: may infiltrate and destroy immediately adjacent structures
- lymphatic: invades lymphatics with spread to regional lymph nodes and beyond
- blood vessels: invades veins and spreads initially to lungs or liver then to more distant sites
- serosal surfaces: may spread across the pleura, pericardium or peritoneum
What is differentiation referring to for neoplasms? How are they graded?
- refers to the extent to which the cells of a neoplasm resemble normal cells both morphologically and functionally
- Usually three grades recognized:
1 = well differentiated (low-grade)
2 = moderately differentiated (low-grade)
3 = poorly differentiated (high-grade)
How are neoplasms classified?
as a rule neoplasms are named for the type of normal tissue they most closely resemble:
- epithelial
- connective tissue (bone and soft tissue)
- lymphoid and hematopoietic
- CNS tumors (gliomas)
- germ cell tumors
- melanoma
Name the following (benign and malignant) epithelial neoplasm:
squamous
benign: squamous papilloma
malignant: squamous cell carcinoma
Name the following (benign and malignant) epithelial neoplasm:
glandular
benign: adenoma
malignant: adenocarcinoma
Name the following (benign and malignant) epithelial neoplasm:
transitional
benign: transitional papilloma
malignant: transitional cell carcinoma
Name the following (benign and malignant) epithelial neoplasm:
liver
benign: adenoma
malignant: hepatocellular carcinoma
Name the following (benign and malignant) epithelial neoplasm:
skin
benign: - papilloma - nevus malignant: - squamous cell carcinoma - melanoma - basal cell carcinoma
Name the following (benign and malignant) mesenchymal neoplasm:
bone
benign:
- osteoma
malignant:
- oasteosarcoma
Name the following (benign and malignant) mesenchymal neoplasm:
fat
benign:
- lipoma
malignant:
- liposarcoma
Name the following (benign and malignant) mesenchymal neoplasm:
cartilage
benign:
- chondroma
malignant:
- chondrosarcoma
Name the following (benign and malignant) mesenchymal neoplasm:
smooth muscle
benign:
- leiomyoma
malignant:
- leiomyosarcoma
Name the following (benign and malignant) mesenchymal neoplasm:
‘striped’ muscle
benign:
- rhabdomyoma
malignant:
- rhabdomyosarcoma
Name the following (benign and malignant) mesenchymal neoplasm:
vessels
benign:
- angioma
malignant:
- angoisarcoma
Name the following (benign and malignant) mesenchymal neoplasm:
fibrous tissue
benign:
- fibroma
malignant:
- fibrosarcoma
Name the following hemopoietic/lymphoid neoplasm:
lymphocytes
malignant:
- lymphoma
- Hodgkin’s disease
- Non-Hodgkin’s disease
Name the following (benign and malignant) hemopoietic/lymphoid neoplasm:
granulocyte
malignant:
- myeloid leukemia
Name the following (benign and malignant) hemopoietic/lymphoid neoplasm:
marrow lymphocytes
malignant:
- lymphocytic lymphoma
Name the following (benign and malignant) hemopoietic/lymphoid neoplasm:
plasma cells
malignant:
- multiple myeloma
What is the role of apoptosis in cancer prevention?
cells that have undergone damage to their DNA may be eliminated by apoptosis before they can grow and form neoplasms
What is the role of apoptosis in cancer progression?
- in some cancers the gene bcl-2 is upregulated and this reduces apoptosis and promotes tumor growth
- in other cancers the gene bax may be upregulated and this promotes apoptosis and may slow cancer growth
How are tumors staged?
- staging of cancers is based on the size of the primary neoplasm, the extent of spread to regional nodes and the presence or absence of distal metastases
- TNM system and AJCC systems