oncology Flashcards
What is the aetiology of head and neck cancer?
Cigarettes
Alcohol
Lifestyle
Genetics
Virus- HPV
Hormones
Immunosuppression
Premalignant oral conditions (leukoplakia, lichen sclerosis)
Radiotherapy exposure
What are signs of cancer?
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
What is our role (pre-tx assessment)?
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
What are short term tx side effects?
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
What are long term tx side effects?
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
What prevention should be given?
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
What are jaw exercises?
Stack wooden spatulas in mouth 7-8s a day
What are examples of soft tissue reconstruction?
1. Radial forearm flap
2. Antero lateral thigh flap
3. Latissimus dorsi
4. Rectus abdominus
5. Para/scapular axis flap
6. Pedicle tongue flap
What are examples of composite reconstruction?
1. Fibula flap
2. Deep circumflex iliac artery flap
3. Scapular flap
4. RFF
What is the Browns classification?
Horizontal and vertical components measuring extent of defects
What does the success of implants require?
Anchorage and stabilisation
Clot form between implant and osteotomy site
Release of growth factors, angiogenesis and migration of osteoprogenitor cells (deposition of bone)
Why is irradiated bone difficult to place implants?
Biological processes for success may be compromised/absent
Mechanical over biological anchorage
Is viable bone capable of remodelling when loaded
What do tissue changes depend on?
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)
What are haematological issues with chemotherapy?
1. Decreased RBCs- anaemia
2. Decreased WBCs- leukopenia
3. Decreased platelet count- thrombocytopenia
What are popular chemo drugs?
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
When do you treat a cancer pt?
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
What tx may you give to a cancer pt?
1. Extractions + other
2. Dental abscess whilst on chemo
3. ONJ/ORNJ (post)
4. Dentures/prosthesis (post)
What is the classification of cancer?
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
What are tx options for cancer?
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
What is surgery?
Fit for GA
Side effects- functional, cosmetic, risk of anaesthetic
Remove tumour w clear margins
May require further tx on review of histology
What is chemotherapy?
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
What are side effects of chemotherapy?
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
When should you tx pts w chemo?
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