chapter 6 Neoplasms Flashcards
What is the most common Type of cancer?
Lung cancer is the most common cause of cancer death in both sexes
What is the most common cancers for each respective gender?
○ In females, breast cancer is the second most common fatal cancer
○ In males, prostate cancer fatality is the most common of all cancers
Oncology
the study of neoplasms
Benign
not capable of metastasizing and usually not capable of causing death
Malignant
capable of metastasizing and capable of causing death
Neoplasm
an uncontrolled growth of new cells, benign or malignant
Tumor
literally, as mass: however everyday language, a neoplasm
Cancer
any kind of malignant neoplasm
Carcinoma
○ a malignant neoplasm of mesenchymal tissue.
○ Bone, cartilage, fat, muscle, or fibrous tissue.
Adenoma
benign tumor of a gland
Adenocarcinoma
malignant tumor of gland epithelium
Fibrosarcoma
malignant tumor of fibrous tissue
What is the difference b/n Benign and Malignant neoplasm?
○ Benign neoplasms grow slowly
○ Malignant neoplasm grow rapidly and are capable of causing death
What causes neoplasms?
Damaged DNA is the root cause
What is the detectable size of a neoplasm?
1 gram
Malignant cells do not spread unless ?
they are able to invade lymphatic channels or blood vessels
The most common genetic defect in human cancer is
mutation of complete loss of the p53 gene –regulates apoptosis
Retinoblastoma
appears as a white mass arising from the retina
DNA Repair
If the DNA repair system is damaged misspelled DNA remains defective and prone to promote cancer
Xeroderma pigmentosa
○ a skin disorder with a predisposition to development of skin cancer
○ caused by faulty DNA repair
Causes of Cancer
○ a transformation of cells (carcinogenesis) that follows injuries that produce direct damage to DNA (mutagenesis)
○ Chemicals, ionizing radiation, and viruses can be responsible
Most common viral cancer causers
○ Human papilloma virus (HPV)
○ Epstein Barr virus (EBV)
○ Hepatitis B (HBV)
Benign neoplasms: shape and structure
○ slow growing and have rounded, smooth outline
○ smooth outline with a rim of compressed fibrous tissue at the edge (a fibrous capsule)
Malignant neoplasms: shape and structure
○ irregular, with fingers of tumors invading adjacent tissue
○ the cut surface has a varied appearance
polyp
a mass that protrudes from an epithelial surface
All neoplasms have two basic components
○ parenchyma, which is the neoplastic tissue
○ the stroma, a non-neoplastic supporting network of blood vessels and fibrous tissue
Structural differences of benign and malignant tumors
○ Benign neoplasms may reproduce tissue recognizably close to normal tissue
○ Malignant nuclei are large and dark because of the presence of excess DNA – a feature called hyperchromatism
Dysplasia
○ a pre-malignant state of tissue (usually epithelium) that is atypical and clearly abnormal but not yet malignant
○ does not always progress to malignancy
carcinoma in situ
○ a tissue state that is literally cancer “in place”.
○ Developed by dysplasia
Once carcinoma invades below the basement membrane it is no longer in situ; it is
○ Invasive
○ invasive malignancies can metastasize
Neoplasms make themselves known by
local pressure effect exerted by the expanding mass of the primary tumor
degree of differentiation of a neoplasm
the degree to which a neoplasm resembles normal tissue in function and appearance
Tumor cells reproduce by forming
○ A clone
○ Identical cells that descend from a single ancestor
All tumor cells are
Monoclonal
Speed Of Tumor Growth
○ It takes far longer for a normal cell to become malignant than for any other stage of tumor growth
○ 30 generations (30 doublings) for a mass to grow large enough, about the size of a grape (about 1 gram)
Lymphomas and leukemias grow more rapidly than most other tumors because
they have high growth fractions
Nourishment of Tumors
Neoplasms develop their own network of blood vessels
As the tumor grows
the clone cells diverges into lines with different characteristics
Tumors that require - are vulnerable to therapy that -
○ require hormone
○ reduces hormone availability
Invasiveness
○ the ability of a neoplasm to invade tissue
○ especially basement membrane, blood vessels, lymphatics
The most feared feature of any malignancy is its
ability to spread by direct invasion of blood vessel
Sarcomas have a propensity for
vascular invasion and widespread metastasis
Carcinomas tend to
invade lymphatics first and metastasize to local lymph nodes
Cytology
the diagnostic study of individual cells for evidence of cancer or other abnormality
Papanicolaou (Pap) smear
screen for cervical cancer
Fine needle aspirate
sometimes under radiological guidance
Biopsy
collection of tissue for diagnosis by surgical excision
in order to treat cancers appropriately
Cancers are graded and staged
Typical grade I cancers
○ (low grade)
○ least aggressive microscopic appearance
Grade II cancers
intermediate
Grade III (high grade)
○ appear to be the most aggressive
○ poorly differentiated and highly atypical
Prostate-specific antigen (PSA)
○ a protein produced by cells of the prostate gland.
○ PSA test measures the level of PSA in the blood.
CEA
○ used mainly to monitor the treatment of cancer patients, especially those with colon cancer.
○ used as a marker for other forms of cancer, including cancers of the rectum, lung, breast, liver, pancreas stomach, and ovary
CA 15-3
○ not sensitive or specific enough to be considered useful as a tool for cancer screening
○ main use is to monitor a person’s response to breast cancer treatment and to watch for breast cancer recurrence
CA-125
used to monitor therapy during treatment for ovarian cancer
AFP
detect and diagnose cancers of the liver, testes, and ovaries
p-53
gene that codes for a protein that regulates the cell cycle and hence functions as a tumor suppression
