Chapter 15 Flashcards
Cite the 2 major dysfunctions in cellular regulation which are needed for cancer development.
Defective cell proliferation (growth) and defective cell differentiation.
Explain how cancerous cells proliferate by loss of contact inhibition and the pyramid effect.
*Normal cells respect the boundaries and territory of the cells surrounding them
*Cancer cells grown in tissue culture have a loss of contact inhibition. They have no regard for cell boundaries and grow on top of one another and on top of or between normal cells.
Describe the function of tumor suppressor genes and what inactivates them.
*Tumor suppressor genes regulate cell growth. They prevent cells from going through the cell cycle. Mutations can change tumor suppressor genes and make them inactive. THis results in a loss of their tumor-suppressing action.
*Eg: BRCA1 and BRCA2
Name the 3 stages of cancer development.
- Initiation
- Promotion
- Progression
Give examples of cancer promoting factors and what could be done to reduce the risk of cancer (4ex.)
*ex. dietary fat, cigarette smoking, alcohol use
*decreasing or complete cessation of each would decrease risk of developing cancer
Define the latent period of stage 2 and what needs to occur before cancer can be detected (3)
*length of time from when 1st genetic alteration occurs and the actual clinical evidence of cancer
*may range 10-40 years
*for diseases to be clinically evident, tumor must reach a critical mass that can be detached.
Describe characteristics of the 3rd stage, progression, in cancer development.
Characterized by:
1. increase in growth rate of tumor
2. invasiveness
3. metastasis: spread of cancer to distant site
Cite the 5 main sites of metastasis.
1.Lungs
2. Liver
3. Bone
4. Brain
5. Adrenal glands
Briefly describe the metastatic process and the importance of tumor angiogenesis. (3)
(1) rapid growth of the primary tumor
(2) tumor angiogenesis
(3) penetration of walls of lymph or vascular vessels
tumor angiogenesis
the process of the formation of blood vessels within the tumor itself
hematogenous metastasis: (3)
- penetrate blood vessels,
- travel through blood throughout body,
- adhere to and penetrate small blood vessels of distant organs
fungating tumors
have a rich blood supply below them, very difficult to operate on these, need to cauterize, huge wounds, etc
most common sites of metastases:
lungs, liver, bones and brain
Compare sentinel lymph node and skip metastasis.
sentinel lymph node: 1st node confronted as tumor cell spreads through the lymphatic system
skip metastasis: when tumor can travel to distant nodes by bypassing local lymph nodes
Explain the importance of cancer classification systems. (4)
- communicates w/ healthcare team
- prep and eval tx plan
- determine prognosis
- compare groups statistically
anatomic site
three classifications
*IDs tissue by origin, atomic site, and behavior of tumor
carcinomas originate from
*embryonal ectoderm (skin, glands)
Sarcomas originate from
embryonal mesoderm (connective tissue, muscle, bone, and fat
Lymphomas and leukemias originate from
hematopoietic system
Histological classification (2)
*appearance of cells and degree of differentiation are evaluated to determine how closely cells resemble tissues of origin
*Poorly differentiated tumors have a poorer prognosis than those closer in appearance to normal cells
Histological classification grades (5)
Grade I: mild dysplasia, well differentiated
Grade II: moderate dysplasia, moderately differentiation
Grade III: severe dysplasia, poorly differentiated
Grade IV: cells are immature, primitive (anaplasia), and undifferentiated; cell of origin is hard to determine
Grade X: cannot be assessed
clinical staging
Based on extent and spread of disease
clinical staging stages (5)
Stage 0: cancer in situ (localized, no invasion or metastasis)
Stage I: Tumor limited to tissue of origin, localized growth
Stage II: Limited local spread
Stage III: extensive local and regional spread
Stage IV: metastasis
explain the 3 goals of cancer treatment:
cure, control and palliation
Cure (2)
*surgery alone or periods of adjunctive systemic therapy (chemo)
*timeframe to “cure” may differ according to the tumor and its characteristics
Control
Patients may undergo an initial course of treatment followed by maintenance therapy for as long as the disease is responding.
* Patients are monitored closely for early signs and symptoms of disease recurrence or progression and the cumulative effects of therapy.
Palliative goal (3)
*relief or control of symptoms
*maintain quality of life
*Palliative care and treatment are not mutually exclusive and can take place concurrently
Describe the surgical approaches to cancer treatment: cure or control (2)
*remove only as much tissue as necessary and spare normal tissue
*A debulking or cytoreductive procedure may be used if the tumor cannot be completely removed (eg: a tumor attached to a vital organ)
Describe the surgical approaches to cancer treatment: prevention (3)
*surgery used to eliminate or reduce risk of cancer in at risk pts
*prophylactic removal of nonvital organs
*usual sites of regional spread may be removed
Describe the surgical approaches to cancer treatment: supportive & palliation
(done when cure and control are no longer possible)
*insertion of gastric feeding tube
*placement of CV access device
*Prophylactic surgical fixation of bones at risk for pathologic fracture
Describe 4 types of regional delivery methods of chemotherapy and the main advantage of this type of delivery.
- Intraarterial chemotherapy
- Intraperitoneal chemotherapy
- Intrathecal or Intraventricular chemotherapy
- Intravesical bladder chemotherapy
Intraarterial chemotherapy (what + what it is tx for)
*delivers the drug to the tumor through the arteries supplying the tumor
*tx for osteogenic sarcoma; cancers of the head and neck, bladder, and cervix; melanoma; primary liver cancer; and metastatic liver disease
Intraperitoneal chemotherapy: (what + what it is tx for)
involves the delivery of chemotherapy to the peritoneal cavity.
*tx for peritoneal metastases from primary colorectal and ovarian cancers and malignant ascites.
Intrathecal or Intraventricular chemotherapy
*tx for metastasis to the CNS
*This method involves a lumbar puncture and injection of chemotherapy into the subarachnoid space
Intravesical bladder chemotherapy:
*instilling chemotherapy into the bladder through catheter and letting it sit for 1-3hrs
Explain acute, delayed, and chronic adverse effects of chemotherapy on normal tissue: acute (2)
*Acute: Occurs during and right after drug administration.
*It includes anaphylactic and hypersensitivity reactions, extravasation or a flare reaction, anticipatory nausea and vomiting, and dysrhythmias
Explain acute, delayed, and chronic adverse effects of chemotherapy on normal tissue: delayed (8s/s)
They include delayed nausea and vomiting, mucositis, alopecia, skin rashes, bone marrow suppression, altered bowel function (diarrhea, constipation), and a variety of cumulative neurotoxicities.
Explain acute, delayed, and chronic adverse effects of chemotherapy on normal tissue: chronic (2)
*Involve damage to organs, such as the heart, liver, kidneys, and lungs.
*Chronic toxicities can be either long-term effects that develop during or right after treatment and persist
Describe the effects of ionizing radiation on cancerous cells (6)
*Delivery of high-energy beams, when absorbed into tissue, produces ionization of atomic particles. The energy in ionizing radiation acts to break the chemical bonds in DNA. The DNA is damaged, causing cell death.
*bone marrow suppression, fatigue, GI probs, integ/muscle reactions, pulmonary effects, and reproductive issues
Contrast external beam vs internal radiation (brachytherapy).
*external (teletherapy): most common. pt exposed to Rad from mega volt machine
*internal (brachytherapy): implantation/insertion of radioactive material into or close to tumor. Minimal exposure to healthy tissues. Often used in combo w/ external
Estimate the reasons for late effects of radiation and chemotherapy.
*SE if chemo/rad that occur mohts to years after remission. Once they occur may be progressive and generally permanent
*Ex: skin telangiectasias to strictures, fistulas, or radiation necrosis.
*the additive effects of malignant chem b4, during, or after course of rad therapy can significantly increase resulting late effects
*most at risk pts are txed w/ alkylating agents w/ high-dose rad
Describe the manifestations of cancer cachexia and relationship with morbidity. (4)
*wasting syndrome: anorexia and or unintentional wt loss
*characterized by: generalized tissue wasting, skeletal muscle atrophy, immune dysfunction, metabolic abnorms
*tx: wt loss cannot be reversed nutritionally (increased risk of mortality)
*best management is to tx cancer, 2nd best is to increase nutrition, 3rd is to use megestrol to sim appetite.
List 3 reasons why cancer patients experience life threatening infections.
- Ulceration and necrosis caused by the tumor
- The tumor compressing vital organs
- Neutropenia from the cancer or cancer treatment
Describe gerontological considerations when determining cancer treatments.
*cancer s/s may be mistaken for age-related changes
*OAs are more vulnerable to complications of cancer and cancer tx
*functional status should be considered when a tx plan is selected
*benefits and risks of tx should be carefully considered.
