Neoplasia Flashcards
What is cancer?
Genetic disorder caused by DNA mutations that are acquired spontaneously (usually) or induced by environ. insult. Also, frequently show epigenetic markers, such as focal increases in DNA methylation and histone alteration.
What are the hallmarks of cancer?
- Self-sufficiency
- Lack of response to growth inhibitors
- Evasion of cell death
- Limitless replication
- Angiogenesis
- Invade local tissues and spread
- Reprogramming of metabolic pathways
- Abilitiy to evade immune system
What is a benign tumor?
One that is thought to remain localized and is amenable to surgical removal. Can still be deadly
What is a malignant tumor?
Cancer, Adhere to any part that they seize. The lesion can invade and destroy adjacent structures and spread to distant sites to cause death.
What are the two basic components of tumors?
- Parenchyma - the part that is the transformed cells.
2. Stroma - the host derived non-neoplastic tissue and blood vessels that support the tumor.
What is a fibroma?
A bengin tumor arises in fibrous tissue
What is a chondroma?
A benign tumor arising in cartilaginous tissue
What is an adenoma?
Benign epithelial neoplasms producing gland patterns.
What is a papilloma?
Benign epithelial neoplasms grown on any surface that produce finger-like fronds.
What is a polyp?
A mass that projects above a mucosal surface to form a macroscopically visible structure
Malignant neoplasms arising in solid mesenchymal tissues are called?
Sarcomas
Malignant neoplasms of epithelial cells are called?
Carcinomas, regardless of which epithelial tissue.
Malignant mesenchymal cells of the blood are called?
Leukemias or lymphomas
What are adenocarcinomas?
Carcinomas that grown in glandular patterns
What are squamous cell carcinomas?
Carcinomas growing as squamous cells.
Tumors showing various types of tumors undergo what process?
Divergent diversification
What is a teratoma?
Special mixed tumor that contains recognizable features of more than one germ cell layer.
In general, what characteristics describe benign tumor?
Genetically simply, harboring rewer mutations than cancers, and genetically stable, changing little in genotype over time
What are the four fundamental features by which benign and malignant tumors can be distinguished?
Differentiation and anaplasia
Rate of Growth
Local Invasion
Metastasis
What is differentiation?
Refers to the extent to which they resemble the normal forebears morphologically and functionally.
Are well-differentiated cells a characteristic of malignant tumors?
They can be, but are more characteristic of benign tumors.
What is important about well-differentiated tumors
They retain a lot of the properties that the original tissue had.
Malignant tumors composed of undifferentiated cells are said to be?
Anaplastic
Is anaplasia associated with pleomorphism?
Yes
What is pleomorphism?
Variation in size and shape, with hyperchromatic staining, and mitoses often are numerous and distinctly atypical.
The more/less rapidly growing and the more/less anaplastic a tumor, the more/less likely it is to have specialized functional activity?
More rapidly growing, more anaplastic tumor, less likely to have specialized function
What is dysplasia?
Disorderly but non-neoplastic proliferation. Typically encountered in epithelial lesions. It is the loss of uniformity of individual cells and in their architectural orientation.
What is the growth rate for more benign tumors?
The grow slowly. Vs cancer which grows rapidly (to distant sites)
The growth rate of malignant tumors correlates inversely with what characteristic?
Their level of differentiation
What is the cancer stem cell hypothesis?
That, like human stem cells, cancer stem cells divide into the cancer and a cancer stem cell. So eliminating the cancer requires elimination of cancer stem cells, which are drug resistant.
Cancer cells grow by?
Progressive infiltration, invasion, destruction, and penetration of the surrounding tissue.
Next to ability to metastasis, what is the distinguishing characteristic of cancer?
Local Invasiveness
What are metastases?
Secondary implants of tumor that are discontinuous with primary tumor
In general, the more/less anaplastic and larger/smaller the primary neoplasm, the more/less likely is metastatic spread?
The more anaplastic and larger, the more likely
What are the three ways in which malignant tumors spread?
Seeding within the body cavities
Lymphatic spread
Hematogenous spread
Spread by seeding is particularly characteristic of what?
Ovarian Cancers
Lymphatic Spread is more typical of carcinomas or sarcomas?
Carcinomas
Hematogenous spread is more typical of carcinomas or sarcomas?
Sarcomas
What is a sentinel lymph node?
The first lymph node to receive metastases from cancers, typically identified with radiologic dye.
What are the most frequently involved secondary tumors in hematogenous spread?
Liver and lungs
What is the primary cause of sporadic cancers?
environmental factors
How old are most people that die from cancer?
55-75
What are the three categories of hereditary cancer?
Autosomal Dominant (Retinoblastoma) Autosomal Recessive (Xeroderma Pigmentosum) Uncertain Inheritance (Majority)
What are acquired preneoplastic lesions?
Acquired conditions which predispose an individual to cancer. i.e. squamous metaplasia and dysplasia of bronchial mucosa
Endoemtrail hyperplasia and dysplasia
What are the four classes of normal regulatory genes involved in cancer development?
Growth-Promoting Proto-Oncogenes, Growth-inhibiting tumor suppressor genes, Genes involved in apoptosis, Genes involved in DNA Repair
What are the two categories of tumor suppressor genes?
Guardians and governors
What are the three common types of nonrandom structural abnormalities in tumor cells?
- Balanced Translocation
- Deletions
- Cytogenetic Manifestations of Gene Amplification
What is miRNA?
They participate in neoplastic transformation either by increasing expression of oncogenes or reducing the expression of TSGs.