Introduction (Week 1 Lecture 1) Flashcards
Cancer incidence
new cancer cases observed over a period of time
Cancer prevalence
numbers of people alive at a specific point in time with cancer
cancer mortality
death due to cancer
Why might cancer be the leading cause of death?
Obesity is the leading cause of cancers
* weight gain cancers are most effected by obesity
Prevalence of cancer in Canada
- 2 in 5 Canadians (44% of men and 43% of women) are expected to develop cancer during their lifetime.
- About 1 out of 4 Canadians (26% of men and 22% of women) is expected to die from cancer.
Average age for cancer
65 years
What are the leading types of cancers in adults?
- prostate for M and breast cancer for F
- Colorectal for both
What are the leading cancers in children?
- Leukemia
- CNS
- lymphoma
Economic burden of cancer
billions of dollars
What are the hallmarks of cancer?
- evading growth suppressors
- nonmutational epigenetic reprogramming
- avoiding immune destruction → tumour cells can cloak and lymphocytes cannot detect
- enabling replicative immortality → infinite cell division
- tumor-promoting imflammation → inflammation response increases blood flow to the tumour
- polymorphic microbiomes → bacteria, fungi, viruses)
- activating invasion & metastasis
- inducing or accessing vasculature
- senescent cells
- genome instability & mutation
- resisting cell death
- deregulating cellular metabolism
- unlocking phenotypic plasticity
- sustaining proliferic signalling
What does staging cancer tell us
Describes the severity of cancer
* Extent of original tumour
* Spread of the tumour
Importance of staging cancer
- Planning appropriate treatment
- Estimating prognosis
- Clinical trial entry
- Provides a common terminology for patient care
Difference between benign and malignant
Primary tumour (benign) growing in place it began but then it can migrate to local tissue and then get into circulation (blood and lymph) and start to reside in other tissue
* benign —> resides in 1 place
* malignant—> wont stop dividing and doesn’t know where it should be so wanders all over the place
How is staging of cancer determined?
- physical exams
- imaging studies
- laboratory tests
- pathology reports
- surgical reports
physical exams to determine cancer stage
physician examines the patients and looks, feels and listens for anything unusual. The physical exam may show the location and size of the tumor(s) and the spread of the cancer to the lymph nodes and/or to other organs.
* i.e. swollen lymph nodes
Imaging studies to determine cancer
capture images inside the body. Imaging techniques include x-rays, computed tomography scans (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) scans. These show the location of the cancer, the size of the tumor, and whether the cancer has spread.
* risk/benefit with radiation causing cancer but benefits outway this
* main way to diagnose tumours to find particular masses with radioactive dye and detecting glucose uptake of tissue to get biological activity
Laboratory tests for determining cancer
include studies of blood, urine, other fluids, and tissues taken from the body. For example, tests for liver function and tumor markers can provide information about the cancer.
* provincial law to biopsy for potential positive identification
pathology reports for determining cancer
may include information about the size of the tumor, the growth of the tumor into other tissues and organs, the type of cancer cells, and the grade of the tumor. Pathology report is typically provided on a biopsy sample, whereas cytology describes findings from an examination of cells in the body.
Surgical reports
tell what is found during surgery. These reports describe the size and appearance of the tumor and often include observations about lymph nodes and nearby organs.
Elements of staging system
- Site of the tumour (Primary)
- Tumor size and number
- Lymph node involvement
- Cell type (morphology of cancer)
- Tumour grade (how closely do they resemble “healthy” cells?)
- Presence or absence of metastasis
Location stages
- In situ
- localized
- regional
- distant
- unknown
In situ
Abnormal cells are present only in the layer of cells in which they developed.
localized
Cancer is limited to the organ in which it began, without evidence of spread.
regional
Cancer has spread beyond the primary site to nearby lymph nodes or organs and tissues.
Distant
Cancer has spread from the primary site to distant organs or distant lymph nodes.
Unknown
There is not enough information to determine the stage.
TMN staging
- T umor, extent of tumor → Tx, T0, Tis, T1, T2, T3, T4 (range of size)
- N odes, extent of spread to lymph nodes → NX, N0, N1, N2, N3 (number od nodes)
- M etastasis, extent of distal metastasis → MX, M0, M1
x = unknown; 0 = not; is = in situ
treatments for cancer
- surgery
- chemotherapy
- radiotherapy
- immunotherapy
surgery treatment
Involves removal of the primary tumor
* May also occur with other treatment modalities
* Usually localized
chemotherapy treatment
Drugs, or a combination of
cytotoxic drugs are used (many classes)
* oral
radiotherapy treatment
Radiation beams directed at tumor
* localized
immunotherapy
targeted therapies
* usually oral
