Inroduction To Cancer W5 Flashcards
What is cancer
▪Disease in which a group of abnormal cells grow uncontrollably by
disregarding the normal rules of cell division
▪Normal cells subject to signals that dictate growth, division,
differentiation or death – cancer cells lose these signals
▪Results in uncontrolled growth and proliferation
▪If allowed to continue and spread, it can be fatal
▪Almost 90% cancer deaths due to spreading – termed “metastasis”
Metastasis
Moved to secondary site ie lymph node or blood vessels
Cancer is a ….
Multi gene and multi step process
Much harder to treat when….
Moves from its primary site - metastasis
Hall marks of cancer
- Sustaining proliferate sigalling
- Evading growth suppressors
- Activating invasion and metastasis
- Enabling replication immortality
- Inducing angiogenesis
- Resisting cell death
Stages of cancer - T
T1 = tumor less that 3cm
T2 = tumor greater than 3cm
T3 = tumor can be any size but is near the airway or has spread to local areas such as the chest wall or diaphragm
T4 = tumor is any size but is located in the airway or has invaded local structures such as the heart or oesophagus
Stages of cancer - N
N0 = no lymph’s affected
N1 = tumr has spread to nearby nodes on the same side of the body
N2 = tumor has spread to nodes further away but on the same side of the body
N3 = cancer cells are present in lymph nodes on the tear side of the chest from the tumor or in the nodes near the collarbone or neck muscles
Stages of cancer - M
M0 = no metastases are present
M1 = tumour has spread to other regions of the body or thie other lung
Stages of cancer - defiistions
Stage 0
Carcinoma in situ (literally means: “cancer in place”). The cancer cells have not yet invaded into surrounding tissues; without invasion the tumor can’t spread and the cure rate is 100%
Stage I
The primary tumor is small but invasive into surrounding tissues and has not spread.
Stage Il
The primary tumor is larger, but there is still no clinical evidence of spread
Stage Ill
The tumor has spread to lymph glands (also called lymph nodes) in that region of the body
Stage IV
The cancer has spread beyond the region where it initiated to a distant tissue or organ
3b cancer
• Cancer in outer lining of colon/rectum wall and has spread to 1-3 nearby lymph nodes but is not in other organs
OR
• Cancer in muscularis propria or outermost layers of colon/ rectum, present in 4-6 nearby lymph nodes, but not other organs
OR
• Cancer in submucosa or in muscularis propria, spead to 7 or more nearby lymph nodes, but not other sites
Cancer stats UK
◦ Every 2 min, someone is diagnosed with cancer
◦ > 1000 new cases of cancer/day
◦ 24% of all deaths are due to cancer
◦ > 450 deaths/day
BUT
◦ 50% survival
◦ 38% preventable cases
Leukaemia
▪Blood cancers
▪Usually originate in the bone marrow
▪High numbers of blood cells that are abnormal and undifferentiated
4 types leukaemia class
4 common types, classed as:
▪ Acute (rapid accumulation of immature blood cells and rapid progression) and chronic (more mature and slower)
▪ Lymphocytic (often those that would differentiate into B cell) or Myeloid (often to granulocytes or monocytes)
Types of leukaemia
▪Acute myeloid leukemia (AML)
▪Chronic myeloid leukemia (CML)
▪Acute lymphocytic leukemia (ALL)
▪Chronic lymphocytic leukemia (CLL)
▪Also other rare types eg hairy cell leukemia
Risk factors
▪Genetics - Family history
▪Age
▪Alcohol
▪Cancer-causing substances
▪Chronic inflammation
▪Diet
▪Hormones
▪Immunosuppression
▪Infectious agents
▪Obesity
▪Radiation
▪Sunlight
▪Tobacco
Genetics
▪Cancer is a genetic disease
▪Mutations in DNA
▪Cancer cells generally have more genetic changes than normal cells
▪Even within same tumor, can have different genetic changes
▪ Inherited
▪ Acquired through lifetime
Hereditary cancers
▪5-10% of all cancers
▪>50 hereditary cancer syndromes – genetic tests
▪Also, cancers that “run in families” but not inherited
genetic mutation eg similar environmental exposure
▪Pre-disposing mutation doesn’t always lead to cancer
▪Common mutated genes – TP53, BRCA1/2, PTEN
▪Genetic testing and ethics
Causing substances
▪Aflatoxins
▪Arsenic
▪Asbestos
▪Benzene
▪Cadmium, Nickel
▪Coal Tar, Coal emissions, Soot
▪Radon
▪Secondhand tobacco smoke
▪Vinyl chloride
▪Wood dust
Cancer type and its prevenatatie % through healthy changes
Breast - 38%
Prostate - 10%
Lung - 33%
Ovarian - 4%
Preventing cancer
▪Don’t smoke or vape
▪Moderate alcohol intake
▪Maintain a healthy diet
▪Keep physically active
▪Reduce exposure to toxins
▪Health and safety in working environment
▪Reduce exposure in water and monitor waste
▪Reduce air pollution
▪Take care with exposure to sunlight
Diagnosis
Early diagnosis correlates with prognosis
▪Family history
▪Genetic testing
▪Lab tests – blood, urine, other bodily fluids
▪Vaccines and screening at different ages
▪Imaging
▪ CT scan, nuclear scan, ultrasound, MRI, PET Scan, X-rays
▪Biopsy
▪ Needle, endoscopy, surgical excision or incision
▪Sentinel lymph node biopsy
Common symptoms
▪None (in some cases)
▪Symptoms common to several illnesses and depend on type:
▪Cough
▪Tired
▪Blood in stool or sputum
▪Weight loss (cachexia)
▪Headaches
Treatments avaliable
▪Surgery
▪Radiotherapy
▪Laser therapy
▪ Photodynamic therapy
▪ Thermal ablation (Heat)
Laser therapy
▪Chemotherapy
▪ Classic chemotherapies (doxorubicin, cisplatin, paclitaxel)
▪ Targeted therapies (tyrosine kinase inhibitors, monoclonal Abs- e.g Herceptin)
▪Immunotherapy
▪ Drug resistance
