Cancer Flashcards
What is neoplasm?
Abnormal mass of tissue growth
Growth continues after stimulus is removed
What do we call the cancer cells?
Parenchyma
What is stroma?
Tissue around the cancer cells that consists of connective tissue, blood vessels, macrophages
How to tell if a tumour is benign or malignant by name?
Benign tumours end in -Oma
Except
sarcoma (stroma)
carcinoma (parenchyma)
Differences between malignant and benign tumours
- Malignant = undifferentiated cells
- benign = differentiated cells
(can tell they are different to normal cells) - malignant grows faster
- malignant infiltrate basal Latima
- Metastasis - benign tissues dont metasis
4 ways of metastasis
Lymphatic
Haematogenous
Body cavity
Contiguous = touching
3 ways of inheriting cancer
- Autosomal dominant =FAP
- Defective DNA repair = Xeroderma pigmentosum
recessive - Familial cancer syndrome = unknown cause but runs in family e.e multiple endocrine neoplasia
Non hereditary cancers
Risk factor e.g. liver cirrhosis and HCC
Inflammation and cytokines can cause cancer
because inflammation creates genomic stress and mutations
What is carcinogenesis?
Acquiring malignancy in over a period of time due to multiple mutation - in steps
- non lethal changes in the cell are the driving force of carcinogenesis
chemical carcinogens :
- no common structural features
- some chemical carcinogens need metabolic conversion from inactive pro- carcinogen to an active ultimate carcinogen
- ## however some act without conversion
4 regulatory genes and examples of cancers caused by loss of regulation in each
Oncogene = burkitts lymphoma mYC
Tumour suppressor genes = BRCA 1/2
DNA repair genes = genomic instability syndrome (not directly oncogenic)
Apoptosis = bcl2 unregulated in lymphomas
Diagnosis and testing
Biopsy
Fine needle aspiration
a bit of tissue is removed and tested to check for the presence of a tumour
Scans
CT, MRI, PET scans
mechanisms of invasion of cancer?
- Lymphatic
- Haematogenous
- Body Cavities
- Contiguous (sharing a common border/touching)
what route do carcinomas follow?
what route do sarcomas follow?
carcinoma = lymphatic
sarcoma = Haematogenous Route
how do tumours use body cavities?
the tumour extending through the pleural cavities/pericardium/peritoneum and maybe even the subarachnoid space
mechanisms of invasion of cancer?
- Lymphatic
- Haematogenous
- Body Cavities
- Contiguous (sharing a common border/touching)
what route do carcinomas follow?
what route do sarcomas follow?
carcinoma = lymphatic
sarcoma = Haematogenous Route
how do tumours use body cavities?
the tumour extending through the pleural cavities/pericardium/peritoneum and maybe even the subarachnoid space
how does carcinogenesis work?
Involves multiple mutations over a period of time
- Malignancy is acquired in a step-wise fashion - tumour progression
- The non-lethal changes in the cell are the driving force of carcinogenesis
what are the classes of carcinogens?
Chemicals • Viruses • Ionising/Non-Ionising Radiation • Hormones • Bacteria, Fungi, Parasites • Miscellaneous
what are the main groups of chemical carcinogens?
Hydrocarbons Amines Nitrosamines Azo dyes Alkylating agents
what are examples of oncogenic viruses?
- Epstein-Barr Virus - Burkitt’s Lymphoma
- HPV - Cervical Cancer
- Hepatitis B Virus - Hepatocellular Carcinoma
what is Oncogenic virus mechanism?
- Viral DNA is incorporated into the host cell DNA
- Oncogenic RNA viral genome is transcribed into DNA by enzymes prior to incorporation
what are DNA oncogenic viruses?
HPV
EBV
HBV
HHV8
what are RNA oncogenic viruses?
HTLV-1
what are radiations that cause cancer?
- Ultraviolet
- Ionising Electromagnetic Radiation can cause an increase in leukaemia
what are the four classes of regulatory genes?
- Oncogenes
- Tumour Suppressor Genes
- apoptosis
- DNA reapir genes
what are types of DNA repair genes?
- Mismatch Repair
- Nucleotide Excision Repair
- Recombination Repair
what are clinical effects of the tumour
- both benign and malignant tumors affect the host
- ## causes worries
what is metabolic cancer cachexia?
- these are side effects of malignant tumours :
- Increased Basal Metabolic Rate (BMR)
- Reduced Fat
- Reduced Muscle Bulk
what are lab methods of cancer diagnosis?
- cytology
- histology
what is staging?
- most important parameter
- Staging combines clinical, radiological and pathological findings.
- main system = TNM
based on several things - Size of the primary TUMOUR
- Has it spread to LYMPH NODES?
- Has is METASTASISED?
what is grading?
Grading = histological , based on differentiation
in UK what screening programmes are present?
- Cervical Cancer
- Breast Cancer
- Colorectal Cancer
what are vaccinations for cancer?
- HPV = cervical cancer
- HBV = liver cancer
