Oncology Flashcards
1
Q
indications for chemotherapy
A
- chemo-sensitive tumours
- primary therapy for haemopoietic malignancies (lymphoma)
- adjunctive therapy for solid tumours
2
Q
why we don’t use chemo for treatment of solid tumours
A
- acts on rapidly dividing cells
- cells in resting phase of cell cycle (G0) are most resistant to chemo
3
Q
treatment options for lymphoma
A
- single agent prednisolone (MST 2-3 months)
- single agent doxorubicin (MST 6-9 months)
- COP (6-9 months, 70-80% remission)
- CHOP (MST 12 months, 75-90% remission)
4
Q
CHOP multi agent protocol
A
Cyclophosphamide
Hydroxydaunorubicin
Oncovin
Prednisolone
5
Q
dangers of chemotherapy
A
- chemo drugs can be found in urine, saliva and faeces
- drugs are mutagenic, abortifacient, teratogenic and carcinogenic
6
Q
safe handling of chemo
A
- PPE
- closed system of administration (luer-lock syringe)
- use of plastic pad (inco sheet)
- use of chemo room
- allocated bins
- no pregnant women handling drugs
7
Q
effects on GI tract from chemo
A
- death of rapidly dividing cells can increase risk of sepsis due to loss of mucosal integrity
- vom, diarrhoea, nausea
8
Q
effects on bone marrow from chemo
A
- low WBC count leads to susceptibility to infections
- low RBC leads to anaemia (low platelets)
9
Q
how to make perivascular injection of chemo drugs less likely?
A
- flush catheter
- appropriate restraint
- highly visible injection sight (unwrap bandage)
- use catheter (don’t go off needle)
- clean stick catheters only (no repeated attempts on one vein)
10
Q
side effects of chemo on organ systems
A
- renal
- cardiac
- hepatic
- urinary (cystitis symptoms)
- dermatological (perivascular admin)
11
Q
cancer definition
A
persistent, purposeless proliferation of host cells, detrimental to the host
12
Q
6 necessary features of neoplasia
A
- evading apoptosis
- self-sufficiency in growth signals
- insensitivity to anti-growth signals
- tissue invasion and metastasis
- limitless replicative potential
- sustained angiogenesis
13
Q
local behaviour of malignant tumour
A
- diffuse, indistinct boundaries
- fixation of tumour in one or more planes
- thickening of adjacent tissue
- spontaneous bleeding or ulceration
14
Q
metastatic potential
A
- ability to spread to distant tissues is a feature of malignancy
spread may be: - via blood
- via lymphatics
- transcoelomic (across pleura)
- iatrogenic
15
Q
what are paraneoplastic syndromes (PNS)
A
- arise from production and release of biologically active substances
- can affect distant organs
- can develop before or after diagnosis of cancer
16
Q
what is haematological PNS
A
- changes in RBC, WBC and platelet counts occurring with neoplasia
- anaemia, thrombocytopenia
17
Q
mechanisms for paraneoplastic anaemia
A
- myelopthisis- invasion of bone marrow by neoplastic cells
- haemorrhage- some neoplasia bleeds, some are severe enough to cause hypovolaemia
- immune-mediated haemolytic anaemia- reactivity between cancer and RBC causes destruction of RBC
- anaemia of chronic disease- due to disordered iron handling
18
Q
hyperviscosity syndrome
A
- due to anything that makes the blood more sludgy
- increased blood cell numbers (erythrocytosis, polycythaemia)
- excessive production of gamma-globulins
19
Q
hyperhistaminaemia
A
- some tumours release histamine and vasoactive amines
- this can be responsible for signs local to the tumour: swelling, erythema, pruritus
- or signs away from the tumour: GI ulcers
- anaphylactic shock is possible if huge, sudden release of histamine
20
Q
immune mediated PNS
A
- due to reactivity between cancer cells and healthy cells
- immune-mediated thrombocytopenia
- immune-mediated haemolytic anaemia
- myaesthenia gravis
21
Q
endocrine related PNS
A
- endocrine tumours and non endocrine tumours can produce hormones
- clinical signs are dependant on the hormone that is excessively produced
22
Q
pyrexia as PNS
A
- thought to be due to production of cytokines by neoplasm
- other causes of pyrexia should be ruled out first
23
Q
cachexia
A
- loss of fat and muscle in patients with cancer
- despite adequate nutritional intake
- thought to be due to production of cytokines by neoplastic cells
24
Q
aims of investigating cancer
A
- histological/cytological diagnosis
- determine extent of local and distant spread
- investigate and treat tumour-related complications
- patients ability to tolerate therapy
- determine prognosis
25
diagnosing cancer
- history
- physical exam
- lab testing
- imaging
- biomarkers (unreliable)
- biopsy (cytology, histopathology)
26
biopsy: cytology samples
- collects individual cells or small clusters
- can be collected through:
- touch/impression preps (moist lesions)
- FNAs- fine needle aspirates
- cytospins of body fluids/effusions
27
biopsy: histology samples
- collects whole pieces of tissue
- more invasive than cytology
- allows tumour grading
- incisional or excision
28
tumour grading
microscopic quantification of parameters that correlate with the clinical aggressiveness of a neoplasm based on the tumours architecture
- invasion of adjacent tissues?
- evidence of metastasis? (presence of neoplastic cells in blood vessels)
29
5 rules of incisional biopsy
1. avoid superficial ulceration, inflammation or necrosis
2. ensure adequate depth
3. try to include a boundary between tumour-normal tissue
4. do not predispose to local tumour recurrence or dissemination (spread of neoplastic cells into the body)
5. do not compromise subsequent therapy
30
when is excisional biopsy indicated?
- when incisional biopsy is too dangerous (tumour in lungs can cause pneumothorax)
- if knowledge of tumour type and grade doesn't change treatment approach (bleeding splenic tumour)
31
clinical staging
- determines extent of neoplastic disease for therapy and prognosis
considers:
- histological grade
- local invasion
- metastatic spread
All 4 views of inflated thorax should be radiographed prior to any treatment
32
TNM staging system
T- tumour- size and invasiveness
N- nodes- assessing drainage for evidence of spread
M- metastasis- assessing spread to other organs
33
aims of cancer treatment
- cure- all cells with capacity for tumour regeneration are eradicated
- remission- cancer had disappeared but cells remain and will relapse over time
- palliation- reduce pain, improve quality of life, correct physiological malfunction
34
surgical excision of tumour
- primary objective is to remove all tumour cells
- more aggressive a malignancy is, the wider the excision margins will need to be
- insufficient margins will leave satellite cells leading to tumour regrowth
35
intracapsular resection (debulking)
- mass excised within their capsule leaving behind neoplastic tissue
- recurrence will occur unless followed with adjunctive therapy
- incurable malignant neoplasia of vital structures (mouth, CNS)
36
post-op complications
failure of surgery occurs when:
- regrowth at primary site due to incomplete resection
- already metastasised
- tumour is systemic (lymphoma)
37
radiotherapy
- external beam radiation therapy, brachytherapy
- causes ionisation, damaging DNA within cells causing cell death
- radiation needs to given to neoplastic tissue only to prevent damage to healthy cells
38
when is radiotherapy an option
- primary tumours with no metastasis but cannot be controlled with purely surgery due to size or site
- oral or nasal cavity, CNS tumours
