oncology Flashcards

1
Q

What is the aetiology of head and neck cancer?

A

Cigarettes
Alcohol
Lifestyle
Genetics
Virus- HPV
Hormones
Immunosuppression
Premalignant oral conditions (leukoplakia, lichen sclerosis)
Radiotherapy exposure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are signs of cancer?

A

Non healing ulcer/swelling/sore (indurated or hard margin)
Red/white patches
Loose teeth
Jaw pain
Lump, bump, mass w or w/o pain
Persistent sore throat
Foul mouth odour
Hoarseness/change in voice (>6 weeks)
Pain in mastication
Dentures no longer fit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is our role (pre-tx assessment)?

A

1. Avoid unscheduled interruptions
2. Pre-prosthetic planning/tx
3. Plan x of teeth (prognosis/risk)
4. Extract (10 days prior radiotherapy)
5. Plan for remaining teeth
6. Preventative advice/tx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are short term tx side effects?

A

Mucositis- 2-4 weeks after radiotherapy
~ice chips, difflam, SLS free toothpaste

Infection- chemo induced neutropenia- oral Candida v common

Xerostomia- radiotherapy damages salivary gland

Ageusia- avoid sweet/sour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are long term tx side effects?

A

Altered anatomy

Rampant dental caries- diet, reduced saliva, radiogenic damage to ADJ

Trismus- surgical scarring/radiogenic fibrosis of MofM

Mastication difficulties- tooth loss

Life long osteoradionecrosis- hypovascularity and necrosis of bone, mucosal breakdown, non healing wound

Xerostomia- challacombe scale

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What prevention should be given?

A

1. Good OH
2. Diet advice
3. Daily 5000ppm fluoride w GC tooth mouse in custom tray
4. Saliva substitute (NOT glandosane- high acidity)
5. Jaw exercises

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are jaw exercises?

A

Stack wooden spatulas in mouth 7-8s a day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are examples of soft tissue reconstruction?

A

1. Radial forearm flap
2. Antero lateral thigh flap
3. Latissimus dorsi
4. Rectus abdominus
5. Para/scapular axis flap
6. Pedicle tongue flap

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are examples of composite reconstruction?

A

1. Fibula flap
2. Deep circumflex iliac artery flap
3. Scapular flap
4. RFF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the Browns classification?

A

Horizontal and vertical components measuring extent of defects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does the success of implants require?

A

Anchorage and stabilisation
Clot form between implant and osteotomy site
Release of growth factors, angiogenesis and migration of osteoprogenitor cells (deposition of bone)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why is irradiated bone difficult to place implants?

A

Biological processes for success may be compromised/absent
Mechanical over biological anchorage
Is viable bone capable of remodelling when loaded

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What do tissue changes depend on?

A

1 Dose (depends on stage/grade of cancer)

2. Mode of therapy (conventional/intensity modulated RT/brachytherapy)

3. Intensity modulated therapy (multiple, non-uniform intensity, limits dose to normal tissue)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are haematological issues with chemotherapy?

A

1. Decreased RBCs- anaemia

2. Decreased WBCs- leukopenia

3. Decreased platelet count- thrombocytopenia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are popular chemo drugs?

A

1. Cisplatin- cytotoxic drug damages DNA and inhibits DNA synthesis

2. Fluoropyrimidines (eg. 5-fluorouracil)- increases radiation sensitivity in cancer cells

For other cancers
1. Monoclonal antibodies eg Ritixumab
2. Bisphosphonates
3. Anti angiogenic biological therapies eg. Sunitinib

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

When do you treat a cancer pt?

A

All active tx during cancer tx- oncology/haem team

If chemotherapy in last 6 months- seek advice from team and avoid non essential

Invasive may be provided IF
-radiotherapy to areas other than head and neck
-chemotherapy more than 6 months ago
-biological/hormonal therapies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What tx may you give to a cancer pt?

A

1. Extractions + other
2. Dental abscess whilst on chemo
3. ONJ/ORNJ (post)
4. Dentures/prosthesis (post)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the classification of cancer?

A

Glandular=adenocarcinoma
Skin/mucosa=sqamous cell carcinoma
C. Tissue= sarcoma
Small cell= small cell carcinoma
Lymph node= lymphoma

Grade (G1-3)

T= size
N= spread to lymph nodes
M= spread to distal organs

Prognostic markers to determine tx pathways eg. HPV association (p16) in head and neck cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are tx options for cancer?

A

1. Surgery
2. Radiotherapy
3. Chemotherapy
4. Hormonal therapy
5. Targeted therapies
6. Immunotherapy
7. Laser therapy
8. Cryotherapy
9. Best supportive care

ANY COMBINATION

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is surgery?

A

Fit for GA
Side effects- functional, cosmetic, risk of anaesthetic
Remove tumour w clear margins
May require further tx on review of histology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is chemotherapy?

A

Drugs affect cell function
Often used in combination

Platinum (Cisplatin, carboplatin etc)
Taxanes (Docetaxel, Paclitaxel etc)
Antimetabolites (5-fluorouracil, methotrexate)
Alkylating agents (Dacarbazine, Temozolamide)
Anthracyclines (Doxorubicin, Epirubicin)

Adjuvant- high risk post op pts, reduce risk of reoccurrence
-5-10% cured as a result, tx carries risks, risks vs benefits

Palliative- improve symptoms and extend life, single drug, less side effects/intensity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are side effects of chemotherapy?

A

N&V
Fatigue
Change in taste
Bowel disturbance
Rash
Hair loss
Neuropathy
Hearing loss
Infertility
Premature menopause
Renal/liver dysfunction
Allergy
Lung/cardiac toxicity
Bone marrow problems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

When should you tx pts w chemo?

A

Preferably all urgent before

If already on-
-find out length of cycle
-3 weekly cycle- maximum risk of suppression 7-14 days- so do just before next cycle
- always check FBC prior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What should you look out for in FBC?

A

Neutropenia
Neutrophils <1

Thrombocytopenia
Platelets <100

Risk of bleeding
Platelets <30

25
Q

What should you do with a dental abscess in an immunocompromised pt?

A

Usually neutropenic sepsis protocol w IV antibiotics etc

Unlikely only source of infection

If no other source found and sepsis not improving- drain, can have platelet transfusion of low w GCSF cover

26
Q

What are more modern targeted agents?

A

Tyrosine kinase inhibitors
- oral
- eg. Dabrafenib, Sunitinib

Monoclonal antibodies
-IV infusion
- eg. Cetuximab, Trastuzumab

27
Q

When should you tx pts w targeted tx?

A

Usually not immunosuppressed
Risk of infection significant
Check FBC and consider antibiotic cover
Always check w oncologist if tx necessary

28
Q

What is immunotherapy?

A

PDL1 inhibitors
Eg. Pembrolizumab

Immune checkpoint inhibitors
Eg. Nivolumab

Can cause itis of any organ- fatal

Can control cancers and sometimes benefit for years

29
Q

What are bone tx in cancer?

A

Adjuvant/palliative
Bisphosphonates, RANK ligand inhibitors, Radium 223

Increased bone resorption is hallmark of metastatic bone disease- osteoclast key target

30
Q

What is the cycle of bone destruction?

A

1. Tumour cells release growth factors and cytokines (RANK ligand overexpression)
2. Osteoclastic resorption stimulated
3. Peptides released by resorption
4. Tumour cell production of factors increased
5. Tumour cell proliferation
6. More bone resorption

31
Q

What is the tx of metastatic bone disease?

A

1. Radiotherapy
2. Endocrine tx
3. Chemotherapy
4. Tumour targeted therapy
6. Orthopaedic intervention
7. Analgesics

32
Q

What is the effect of bisphosphonates on the cycle of bone destruction?

A

1. Decrease activity of osteoclasts
2. Less peptide release
3. Slowed tumour cell growth
4. Reduced production of factors
5. Decrease in bone resorption

33
Q

What are side effects of bisphosphonates?

A

Oral
-upper GI inflam
-diarrhoea and ab pain

IV
-fever and myalgia (temporary)
-electrolytes and mineral adverse events
-rare renal toxicity
-risk of ONJ

34
Q

What is the effect of Denosumab on the cycle of bone destruction?

A

1. Binds to RANK ligand
2. Inhibits osteoclast formation, function and survival

Given subcutaneous
No renal safety concerns
Fewer acute reactions
Side effects- back/arm/leg/muscle pain, high cholesterol, bladder infection, hypocalcaemia

35
Q

What is radiotherapy?

A

Ionosing radiation interacts w water molecules to create free radicals which cause DNA damage
Normal and malignant cells damaged
Normal can repair if tolerance not exceeded

Energy of photons is higher in therapeutic over diagnostic

Diagnostic- >150kV
Therapeutic- 80kV-20mV

Radical/adjuvant/palliative/neoadjuvant

36
Q

What are the tx modalities of radiotherapy?

A

X-rays- superficial/mega voltage

Electron tx

Brachytherapy

37
Q

What is HPV?

A

DNA virus
72 L1 capsid proteins
Orogenital transmission
Type 16 most common

38
Q

Who makes the decision for the cancer pt?

A

Pt
Surgeon
Oncologist
Specialist nurse
Plastic surgeon
Speech and language therapist
Dietician

39
Q

What investigations are needed for head and neck cancer?

A

Clinical exam
Blood tests
Exam under anaesthesia
Biopsy
Imaging (MRI/CT/PET)

40
Q

What are side effects of head and neck radiotherapy?

A

EARLY
Xerostomia
Altered/loss of taste
Mucositis
Loss of hair
Fatigue
Cough
Soreness of skin

LATE
Xerostomia
Altered taste
ORNJ
Alopecia
Hypothyroidism
SC fibrosis
Second malignancy
Altered pigmentation

41
Q

What is the tx of ORNJ?

A

Surgical debridement
Pentoxyphylline
Hyperbaric oxygen

42
Q

What is the log kill hypothesis?

A

Chemo drugs kill a constant proportion of cells rather than a constant no of cells

So solid tumours have a poor response whereas disseminated cancers respond well

43
Q

How is the cell cycle involved?

A

CCS- drugs that act on cell cycle
Eg. Antimetabolites, taxanes, vinca alkaloids)

CCNS (cell cycle non specific)- drugs that sterilise tumour cells whether they’re cycling or resting in the G0 compartments
Eg. Alkylating agents, platinum analogs

44
Q

What are examples of chemo drugs?

A

CSS
5-fluorouracil (S phase) pyrimidinr analogue
Methotrexate (S phase) folic acid analogue
Vinblastine (M phase)

CCNS
Decarbazine
Busulfan
Cisplatin

45
Q

What are alkylating agents?

A

Highly reactive carbonium ion
Transfer alkyl groups to nucleophilic sites on DNA bases
Cross linkage, abnormal base pairing, DNA strand breakage

6 major chemical classes

Increase risk of secondary malignancies

Bone marrow depression, N&V

46
Q

How is there resistance of alkylating agents?

A

Increased activity of DNA repair enzyme
Increase metabolic inactivation of drug
Decrease influx of drug

47
Q

What are platinum analogues?

A

Heavy metals
Form highly reactive platinum complexes
Intra strand cross linking
DNA damage
Inhibits cell proliferation

48
Q

What is Cisplatin?

A

Highly bound to plasma protein
Conc in kidney, intestines and testes
Poorly penetrates blood brain barrier
Emesis, nephrotoxicity, peripheral neuropathy, ototoxicity

49
Q

What are antimetabolites?

A

Fraudulent substrates for biochem reactions
Substitute normal building blocks of RNA and DNA

50
Q

What is methotrexate?

A

Binds to active catalytic site of DHFR
Inhibits synthesis of THF
Interferes w formation of DNA, RNA and cellular proteins

Cytotoxic, immunosuppressive and anti inflam

Side effects- megaloblastic anaemia, leukopenia, alopecia, nephropathy

51
Q

What is 5 fluorouracil?

A

Activation via complex series of enzymatic reactions
Between ribosyl and deoxirybosil nucleotide metabolites

5-10 min half life

Side effects- N&V, headache, mood disorder, cardiotoxicity, GI problems, vein pigmentation, local pain, dermatitis

52
Q

What are vinca alkaloids?

A

Inhibit tubulin proliferation
Disrupts assembly of microtubules
Mitotic arrest in metaphase
Cell death

53
Q

What are taxanes?

A

Enhance tubulin polymerisation
Promotes microtubule assembly in absence of required proteins and guanosine triphophate
Inhibits mitosis/cell division

54
Q

What are anti tumour antibiotics?

A

Bind to DNA through intervals toon between specific bases
Blocks synthesis of RNA and DNA, DNA strand scission, interfere w cell replication

Eg. Bleomycin, doxorubicin

55
Q

What are hormones and antagonists?

A

Eg. Glucocorticoids, estrogens, estrogen antagonists

56
Q

What do bisphosphonates do?

A

Slow rate of growth of bone crystals
Reduce skeletal events
Lower calcium levels

GI toxicities- N&V, indigestion, oesophagitis, diarrhoea

57
Q

What needs to be considered w drug combination?

A

Efficacy
Toxicity
Optimum scheduling
Mechanisms of interaction
Avoidance of arbitrary dose changes

58
Q

What are some direct oral complications of chemo?

A

Oral mucositis
Taste dysfunction
Neurotoxicity
Salivary gland dysfunction
TMJ dysfunction
Dentinal hypersensitivity
BRONJ