class 5 cancer Flashcards
Cell Death -2 major ways
Apoptosis
* Necrosis
Foundational Concept:
Apoptosis
- Normal process to remove injured or
worn-out cells - Can be a normal physiologic process or a
result of a pathologic process - “Cell Suicide” – involves controlled cell
destruction and normal cell deletion and
renewal (ie) RBC’s - Process does not elicit an inflammatory
response
Necrosis
- Cell death in an organ or tissue that is still
part of the living person - Interferes with cell replacement and tissue
regeneration - Pathologic form of cell death, unregulated
and injurious - Liquefaction necrosis
- Coagulation necrosis (Grey firm mass)
- Caseous necrosis (Cheesy material)
- Produces an inflammatory response
- An overgrowth of infectious agents can
create a decreased blood flow
Gangrene
- A considerable mass of tissue undergoes
necrosis - Dry or moist (wet) gangrene
- Gas gangrene (Closteridium bacteria
invades)
Angiogenesis
Is the formation of new blood vessels
Angiogenesis-how is to connected to cancer
To divide rapidly and indefinitely tumor
cells need adequate supply of nutrients
- Cancer cells control angiogenesis and
establish their own blood supply - Solid tumors need to create a new
capillary network to “feed” themselves - Serves as a route for metastases (spread)
Cell Proliferation
- Process of cell division (cell reproduction)
- Adaptive mechanism for replacing body
cells when old ones die
cell proliferation- how it connects to cancer
…Cancer cells fail
to respond to the normal cues controlling
cellular reproduction. Instead, they
typically go through the cell cycle at an
increased rate and frequency. They have no contact inhibition
Cell Differentiation
- Process where proliferating cells are transformed
into different and more specialized cell types - Determines what a cell looks like, how it will
function, and how long it will live - (ie) red blood cells live 120 day
what cells cant reproduce and why
cardiac and neuron cells because they are fully differentiated
Neoplasia
- Defects in these two processes, cell
proliferation and cell differentiation
underlie the nature of neoplasia - New growth = Neoplasm
Anaplasia
- Lack of cell differentiation, occurs in
cancerous tissue - Causes a cancer cell to lose its ability to
perform previous functions and bears
little resemblance to its tissue origin - Highly anaplastic cells usually indicate a
particularly aggressive tumor
What is a benign tumor? and how do they cause harm
A non-cancerous growth that does not invade nearby tissues or spread to other parts of the body.
Rarely causes death
Causes harm by putting pressure on the
surrounding tissues
What are common characteristics of benign tumors?
Slow-growing, well-defined, encapsulated, non-invasive, and non-metastatic.
What is a malignant tumor?
A cancerous growth that can invade nearby tissues and spread to other parts of the body. Less well-differentiated cells- anaplastic
What are the characteristics of malignant tumors?
invasive growth, potential for metastasis, irregular shape, rapid growth, and diverse cell types.
Name the four main types of malignant tumors.
Carcinomas, sarcomas, lymphomas, and leukemias.
What is a carcinoma?
A malignant tumor that arises from epithelial cells, such as breast or lung cancer.
What are sarcomas?
Cancers that originate from connective tissues like bones, muscles, and fat.
Oncogenes
An oncogene is a gene that has the potential to cause cancer. In tumor cells, they are often mutated and/or
expressed at high levels. Problem when turned”on”
Tumor suppressor genes
genes in the body that help regulate cell growth and division, prevent excessive cell proliferation, and repair DNA.
When these genes function properly, they act as “brakes” on the cell cycle, ensuring that cells do not grow uncontrollably. If these genes are mutated or inactivated, it can lead to cancer.
Repair or mutator genes
These genes help correct errors that can occur during DNA replication or as a result of environmental factors like radiation and chemicals. When these genes are mutated or malfunctioning, the ability of cells to repair DNA is compromised, leading to an increased risk of cancer.
3 main types of carcinogens
- chemical carcinogen
- physical carcinogen (radiation)
- infectious pathogen (viral)
2 Types of Cancer
- Solid Tumors
- Confined to a specific tissue or organ
- Able to metastasize to another site
- Hematologic Cancer (systemic)
- Involves blood-forming cells that are
naturally located in blood and lymph
systems - Disseminated from the beginning
3 ways Cancer is Spread
- Direct invasion and extension (into
surrounding tissue) - Seeding (into body cavity)
- Lymphatics and vasculature carry cancer
cells from one part of the body to
another(metastases)
impairment or decline in the
surveillance capacity of the immune
system, 3 factors
- Immunosuppressant drugs
- Immunodeficiency disease
- Aging immune system
Steps of Metastasis
Break loose from primary tumor
Invade the extracellular matrix
Gain access to a blood vessel (or
lymph)
Survive its’ passage in the bloodstream
Emerge from the bloodstream (or
lymph) at a favorable location
Invade the surrounding tissue & grow
Clinical Manifestations of cancer
- Anemia
- Compress and erode blood vessels resulting in ulceration (losing blood)
- Pain (palpable mass)
- Invades and compresses adjacent tissue
(crowding, crushing, obstruction) - Loss of function
- Variable depends on site
-immunocompromised gets sores in mouth that are very painful
-extreme fatigue
Cachexia
- Weight loss and wasting of body fat due to:
- N/V, mouth sores, altered taste
- Depression or pain
- Loss of appetite (anorexia)
- Leads to weight loss and malnutrition
- Tissue necrosing factor hormone
-takes away muscle mass and fat stores
fatigue in cancer patients cause
- The increased metabolic demands of dividing cells
- Toxic response to chemo
- Emotional drain
- Often is anemic
*Takes nutrients from other cells
What are paraneoplastic syndromes?
Disorders triggered by cancer that are not directly caused by the tumor itself, often due to immune responses or substances produced by the tumor.
How do paraneoplastic syndromes arise?
They can arise from hormones or substances produced by the tumor or from the immune system’s reaction to the cancer.
Diagnostic tests
- History and physical examination
- Imaging studies
- Biopsy and cytology studies
- Tumor markers and other blood, urine or
tissue tests
What are tumor cell markers?
Substances produced by cancer cells or by the body in response to cancer, found in blood, urine, or tissues.
Can help identify the type of tumor, monitor
its progression, and identify people at
high risk for this type of tumor
Stage & Grade of cancer
used to determine the best
treatment protocol for an individual.
Stage (TMN Classification System)
T- location and size of primary tumour; extent to which cells
have spread to neighboring tissues/structures {T 1-4}
- N- extent to which tumour cells have spread to lymph nodes
- M- extent to which distant metastases are present
what is grade of cancer
Describes degree of differentiation of cells and rate of
mitosis of cells
Staging of Solid Tumours (1-4)
*Stage 1: no lymph involvement, no mets and tumors are
less than 2 cm in size
*Stage 2: local lymph involvement, no mets and tumors are
less than 5 cm in size
*Stage 3: nodal involvement, no mets, tumors are over 5
cm
*Stage 4: nodal involvement, mets, tumors can be greater
than 5 cm.
Grading scale 1-4
Grade 1
* Cells well-differentiated
- Grade 2
- Cells moderately differentiated
- Grade 3
- Cells poorly differentiated
- Grade 4
- Cells are un-differentiated (de-differentiated)
2 main classifications of lung cancer
Non-Small Cell Lung Cancer (NSCLC)
This is the most common type of lung cancer, accounting for about 85% of all cases.
Includes squamous cell, adenocarcinomas, and large cell carcinomas
Small Cell Lung Cancer (SCLC)
This type accounts for about 15% of lung cancer cases and is more aggressive than NSCLC. It tends to grow and spread rapidly.
Small, round, to oval cells
Highly malignant (brain mets common)
Metaplasia
Replacement of one cell type with another cell type –one that can better endure the stressor or change
early stages of lung cancer
- cough/chronic cough
-dyspnea (SOB)
-hemoptysis (cough blood)
-chest and shoulder pain - recurring temp
-recurring resp. infections/ always having a cold
late stages lung cancer
-bone pain/spinal cord compression
-chest pain/tightness
-dysphasia
-head and neck edema
-blurred vision and headache
-weakness, anorexia, weight loss, cachexia
-pleural effusion
-liver metastasised
why does hoarseness happen with lung ca
involvement of
the laryngeal
nerve
why does dysphasia happen with lung ca
because of
compression of
the esophagus
Diagnostic Tests for lung cancer
CXR
* CT Scans
* MRI
* Sputum cytology
* Fibreoptic bronchoscopy
* Transthoracic fine needle aspiration
colorectal cancers also known as
adenocarcinomas
Manifestations (Ca of Colon)
- Bleeding
- (occult or frank blood in the stool; highly
significant early symptom) - Change in bowel habits
- Diarrhea, constipation
- Sense of urgency
- Feeling of incomplete emptying of the bowel
- Anemia
- Anorexia
- Weight loss
- Pain is a late symptom
Staging of Ca of Colon
I: Limited to invasion of the
mucosal & submucosal layer of the
colon
*II: Involves the entire wall of the
bowel without lymph node
involvement
*III: Invasion of the serosal layer &
regional lymph node involvement
*IV: Far-advanced metastases
Diagnosis of colon cancer
- Stool for occult blood
- (if 50 years of age or older
every 1-2 yrs) - Digital rectal exam
- Barium enema
- Sigmoidscopy
- Colonoscopy (when + screening test)
- Carcinoembryonic antigen (CEA)
- If increased risk screen earlier and more often