Flashcards
Week 8
Flashcards do conjunto (39)
- 1Define benign-Localised lesion
-Can affect surrounding tissues by mass effect
-Doesn't metastasise - 2Define malignant-Aggressive behaviour
-Invade local tissue - 3What are the 2 basic components of tumours?-Parenchyma
-Supporting stroma (connective tissue and blood vessels) - 4Examples of benign mesenchymal tumours-Fibroma
-Osteoma
-Leiomyoma
-Angioma - 5Examples of benign epithelial tumours-Adenoma
-Cystadenoma
-Papilloma
-Polyp - 6Define mixed tumoursDerived from a single germ cell layer that differentiates into more than 1 cell type
- 7Define teratomasDerived from more germ cell layers and so it composed of many parenchymal cell types
- 8What are the characteristics of of neoplastic cells?-Pleomorphism
-Abnormal nuclear morphology
-Abundant atypical mitosis
-Loss of polarity
-Tumour giant cell
-Ischaemic necrosis - 9Define dysplasia-Loss of cellular uniformity and organisation
-Once the inciting stimulus is removed, it reverts back to its normal state - 10What determines the rate of growth?-Excess cell production over cell loss
-Growth fraction (% of actively proliferating cells in a tumour)
-Inversely correlated with the level of differentiation - 11Describe what a benign tumour would look like-Expansile mass
-Ring of condensed capsule surrounds the tumour
-Tumour does not penetrate the capsule
-Can be enucleated surgically - 12Describe what a malignant tumour would look like-Invasive and infiltrates surrounding tissue
-Lacks well-defined capsule
-Surgery requires mass to be removed with a healthy margin - 13What are the 3 main mechanisms of cancer spread?-Direct extension/local spread
-Lymphatic spread
-Haematogenous spread via venous system - 14How does direct extension/local spread work?-Tumour extends directly into surrounding tissue, organs, spaces
-Occurs through the wall of the primary organ
-Seeding can occur in the peritoneal/pleural cavity where detached cells enter the fluid - 15What are the common primaries of cancers which spread in the peritoneum?Intraperitoneal organs
-oesophageal
-gastric
-colorectal
-pancreatic
-ovarian - 16Where does peritoneal spread occur to?-Peritoneal surfaces of organs eg. liver
-Can plant on omentum (omental cake)
-Transcoelomic spread can occur (spread into cavities) - 17What is the cisterna chyli?Receives lymph from lower limbs, lumbar trunks and intestinal trunk
- 18Describe lymphatic spread of cancer-Cell detach
-Enter lymph capillaries draining adjacent tissues (no functional capillaries in tumour)
-Colonise distant tissues - 19What is the sentinel lymph node(s)?-First lymph node/group of lymph nodes that drain a tumour
- 20What are sentinel lymph nodes used for?-Predicting the likelihood of metastases (staging)
-Identified via methylene blue or a radioactive tracer and biopsied
-Used in staging for breast, colon cancer and melanoma - 21How does haematogenous spread of cancer occur?-Cells detach
-Enter venous vessels draining the tissue
-Commonly metastasise to liver, lung, brain and bone - 22How does haematogenous spread of the liver occur?-From structures drained by the portal venous system eg. GI tumours
-Venous drainage of the liver is via the mesenteric veins and hepatic portal system - 23How does haematogenous spread of the lungs occur?-From structures drained by the systemic venous system (harder to determine)
-Cells enter the right circulation via the SVS/IVC into the RHS of the heart and pulmonary system - 24What are examples of cancers that commonly metastasise to the bone?-Breast
-Lung
-Thyroid
-Kidney
-Prostate - 25Define screening-Investigation of asymptomatic people in order to classify them as likely or unlikely to have the disease
-Those who appear likely to have the disease, undergo further testing before a diagnosis is made - 26What are the essential prerequisites for screening (WHO)? (10)-Condition is an important public health problem
-Accepted treatment is present
-Facilities to do so should be present
-Recognised presymptomatic/latent phase
-Suitable test or examination
-Test should be acceptable
-Natural history of disease should be understood
-Agreed policy on treatment
-Economically balanced
-Case funding should be continuous - 27Characteristics of diseases suitable for screening-Relatively common and have severe consequences
-Must have a preclinical phase where it is undiagnosed but detectable
-Early treatment must offer some advantage
-Evidence of net benefit - 28Describe lead time bias-The day diagnosis is made is brought forward by screening
-There is an apparent increase in survival since the period between detection and death is longer than in those not screened - 29Describe length bias-Diseases which are screened, are more likely to be less aggressive
-Less aggressive conditions are more likely to be present for years
-More aggressive conditions are likely to develop fully between successive routine screening points - 30Define sensitivityProportion with condition who test positive
true positive/total disease present - 31Define specificityProportion without the condition who test negative
true negative/disease absent - 32Define positive predictive valueProportion with positive test who have the condition
true positive/positive screening result - 33Define negative predictive valueProportion with negative test who do not have the condition
true negative/negative screening result - 34D-Free screening for women aged 50-70 every 3 years
-Ductal carcinoma in-situ numbers have risen since it is not palpable (only detectable on mammograms) - 35What are the problems with PSA testing?-2/3 of men with elevated levels do not have prostate cancer
-Test is unreliable between different labs
-Natural history of the disease is poorly understood
-Substantial proportion receive unnecessary treatment with serious s/e's - 36What are the objectives of cancer treatments?-Cure the patient
-Prolong patient survival
-Palliate symptoms - 37What is the purpose of phase 1 RCTs?To find a safe dose of a new treatment and understand toxicities. Determines dose and toxicities.
- 38What is the purpose of phase 2 RCTs?To determine if new treatment has sufficient efficacy to be worthy of further investigation. Determines anti-disease activity.
- 39What is the purpose of phase 3 RCTs?To provide sufficient evidence to potentially change clinical practice. Determines long-term efficacy measure.
Informações
- Descrição
- Anatomy and cancer Cancer screening and prevention How do you know that a treatment works?
- Criado por
- Dolu Falowo
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- 3
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