Neoplasia Flashcards
What is contact inhibition in normal cells?
Normal cells stop proliferation when they are at a certain density and in contact with each other.
What is a neoplasm?
The term neoplasm refers to an abnormal mass of tissue in which the growth exceeds and is uncoordinated with that of the normal tissues
What is autonomous growth in tumor cells?
Tumor cells continue to proliferate even when they touch each other.
How are benign and malignant neoplasms distinguished?
They are distinguished by:
* Cell characteristics
* Rate and manner of growth
* Capacity to invade and metastasize
* Potential for causing death
What is the process of invasion in cancer?
Invasion results in seeding in body cavities and tumors usually have poorly defined edges.
What types of invasion are there?
The types of invasion are:
* Mesenchymal
* Amoeboid
* Coordinate
* Cohort
What is metastasis?
Metastasis refers to the spread of cancer cells to a secondary tumor in a different location than the primary tumor.
What is intravasation in the context of metastasis?
Intravasation is when cancer cells reach the vasculature.
What is extravasation?
Extravasation is the process of cancer cells moving from the bloodstream to a new location.
What is a sentinel node?
The sentinel node is the first lymph node where the primary tumor drains.
What percentage of cancer deaths are attributed to metastasis?
90% of cancer deaths are due to metastasis.
True or False: Tumor cells exhibit contact inhibition.
False
What are the two categories of cancer genes?
Cancer genes can be classified into oncogenes (gene overactivity) and tumor suppressor genes (gene underactivity).
What are proto-oncogenes?
Proto-oncogenes are normal genes that become cancer-causing oncogenes when mutated.
What is an example of a proto-oncogene?
An example of a proto-oncogene is growth factors and their receptors.
What are tumor suppressor genes?
Tumor suppressor genes are present with gene underactivity, and their inactivity promotes cancer.
What is the most common tumor suppressor gene?
The most common tumor suppressor gene is P53, which allows cells to stop proliferation.
What are the types of tumors in oncogenesis?
Oncogenesis includes monoclonal tumors, polyclonal tumors, and the multistage process of tumor cell transformation.
What are the three phases of tumor transformation (carcinogenesis)?
The three phases are: 1. Initiation, 2. Promotion, 3. Progression.
What occurs during the initiation phase of carcinogenesis?
Initiation describes the stage where cells are exposed to a carcinogenic agent, causing irreversible changes.
What happens during the promotion phase of carcinogenesis?
Promotion allows for prolific growth of cells triggered by growth factors and is reversible if the promoter is removed.
What characterizes the progression phase of carcinogenesis?
Progression manifests when tumor cells become malignant, promoting growth, invasiveness, and metastatic competence.
What are tumor markers?
Tumor markers are antigens expressed on the surface of tumors. They can indicate cancer presence and are used for screening, prognosis, and monitoring treatment. Common markers include AFP, CA 15-3, hCG, and PSA.
What is a tissue biopsy?
A tissue biopsy involves the removal of a tissue sample to understand its histology. This can be performed using a needle biopsy, endoscopic method, or laparoscopic surgery.
