Oral Cancer Management Flashcards
What does the radiologist do?
Diagnosis - does pt have imaging signs of cancer
Staging - how far has cancer spread
Surveillance - has the cancer recurred after tx?
What does staging of cancer do?
To define the extent of the primary cancer, including structures that it invades and structures that might be involved in the resection if surgery is needed
Spread to regional lymph nodes is evaluated
TNM staging:
- Tumour
- Nodes
- Metastases = spread from local draining nodes
What imaging is used for oral cancer? What is used if this is contraindicated?
MRI If contraindicated (pacemaker or claustrophobic) = CT scan
Why stage cancers?
Helps identify most appropriate tx options
- Curative or palliative route, surgery, chemo, combined tx
Predict prognosis - larger cancer = extensive lymph node spread = poorer prognosis than smaller cancers without lymphadenopathy
Advanced diseases = staging may spare the patient surgery that won’t have a significant effect on survival
TNM classification?
T-stage
= Primary tumour
- Mostly based on size and depth of invasion of underlying tissue
- T0 = no evidence of primary tumour
- T1 = <2cm, depth of invasion less than 5mm (measure with ruler or from MRI scan)
- T2 = <2cm and DOI >5mm BUT <10mm
OR >2cm and <4cm, DOI <10mm
- T3 = >4cm or DOI >10mm
- T4 = invades deep structures e.g. bone, masticatory muscles
N stage
= Lymph nodes
N0 = no lymph node metastases
N1 = single ipsilateral node on the same side as the primary tumour <3cm in diameter, ENE negative
N2a = single ipsilateral node >3cm but <6cm, ENE negative
N2b = multiple ipsilateral nodes <6cm, ENE negative
N2c = contralateral/bilateral node(s) <6cm, ENE negative
N3a = any node >6cm, ENE negative
N3b = any node that is ENE positive
M stage
- M0 = no distant metastases
- M1 = distant metastases present e.g. lung
What is ENE?
Extra-nodal extension Spread of carcinoma through fibrous capsule of a lymph node into surrounding soft tissues = ENE Detected clinically (fixation/tethering, skin invasion, cranial nerve defects) with radiological confirmation or pathologically
Stage 1?
T1, N0, MO
Stage 2?
T2, NO, MO
Stage 3?
T3 NO MO
T1, 2, 3 N1 MO
Stage IVa?
T4 N0 M0
T4 N1 M0
T1,2,3,4 N1,N2 M0
Stage IVb?
T1,2,3,4 N3, M0
Stage IVc?
T1,2,3,4 N0,1,2,3 M1
Survival rates for mouth cancer?
55% live for at least 5yrs
Lip 90% for 5yrs
Tongue 50% for 5 yrs
Oral cavity 47% for 5 yrs
What impacts the prognosis of oral cancer?
Lymph node spread
- Prognosis falls by half when comparing N0 pts to N1 pts
- Falls by half for spread to the contralateral neck (N2c)
Left tongue mass, max diameter 52mm, DOI 12mm
2 pathological lymph nodes L neck largest 28mm, R neck clear
No ENE
What TNM stage is this?
T3 N2b left lateral tongue cancer
If the pt is M1, what tx is provided?
Palliative care rather than curative
Where do distant metastases usually occur with oral cancer? How are these detected
Usually occur in the chest, either as spread to mediastinal lymph nodes or as lung metastases
= Chest imaging in diagnostic wax up
Chest x-ray will exclude large lung metastases, CT scan is more sensitive and will identify small deposits
Why is detection of cancer recurrence difficult clinically?
Surgery and radiotherapy alter appearance of oral cavity and neck, as well as texture, due to scarring
How to check for recurrence?
Imaging helps identify recurrent tumour
But distinguishing the effects of tx from cancer recurrence can be difficult
= MRI
If MRI and clinical exam uncertain = PET scan can be used to measure glucose metabolism
- Cancer cells = more metabolically active than normal cells = useful to identify site for biopsy
What is the role of the pathologist in oral cancer?
Prior to tx - establish/confirm the diagnosis, report on prognostic features
During tx - provision of frozen section diagnosis to determine completeness of excision
After tx - determine completeness of excision, report on factors important in prognosis and planning of further tx
What info is found from an incisional biopsy/specimen?
Depth of invasion
- Superficial or into underlying structures
Pattern of invasion
- Are the tumour islands cohesive or non-cohesive?
- Non-cohesive = cancer cells travel = more aggressive
Degree of differentiation
- Well, moderately or poorly differentiated
- Poorly = may not resemble epithelium
Distance of tumour from mucosal and deep excision margins
- > 5mm = clear margin
- <5mm = close margin
- <1/at margin = involved margin
Tumour in lymphatics
Perineural infiltration: tumour in and around nerves
What do pathologists do regarding frozen section reporting?
Why is this a problem?
Determine if surgeon has completely excised the tumour - if not, surgeon may remove more tissue
BUT an issue as:
- Prolongs operation
- Expensive and time consuming
- May not increase pt survival/prognosis
What can the pathologist report on after treatment?
Extent of spread
- Primary tumour
- Any tumours present in lymphatics, BVs and nerves
- Tumour to lymph nodes in the neck
- From nodes into the tissues of the neck (ECS)
Completeness of excision - soft tissue and bone - is the tumour completely removed? - with specimens black is painted on the anterior margin for orientation
Primary tumour final report consists of..?
Primary tumour
- Diameter of tumour
- Depth and pattern of invasion
- Grade of tumour, clearance from deep and mucosal excision margins
- Invasion into bone
- Clearance of bone margins
- Lymphatic, vascular or peri-neural invasion
Neck dissection final report consists of..?
Number of nodes at each level
Number containing metastasis at each level
Number showing extranodal extension at each level
pTNM stage (TNM7 and 9 together)
What do pathologists report on?
Completeness of excision and other factors important in prognosis
What is vital in the treatment of head and neck cancer?
A multi-disciplinary team (MDT) approach = involves drawing appropriately from multiple disciplines to explore problems outside of normal boundaries and reach solutions based on a new understanding of complex situations
- plastic surgeons
- ENT surgeons
- maxillofacial surgeons
- Oncologists
- Restorative dentist
- Nurses
- Palliative care
- Pathologist
- Radiologist
- Dietitian
- Data manager
- MDT coordinator
What does the oral rehabilitation 2013 contract state?
Appropriate assessment of a pt’s oral rehabilitative needs across the pathway and provider must ensure specialist oral rehab care is provided
What does SIGN90 state?
Pt’s with head and neck cancer, oral cancers or whose teeth are involved in the radiotherapy field have an opportunity for a pre-treatment assessment
What are the aims of a pre-treatment dental assessment?
Avoid unscheduled interruptions to primary tx as a result of dental problems
Pre-prosthetic planning/treatment e.g. planning for primary implants
Planning for extraction of teeth which are of doubtful prognosis or are at risk of dental disease in the future and are in an area where there would be risk of osteoradionecrosis
Extractions must be carried out as early as possible in the pt’s journey - at least 10 days prior to radiotherapy
Planning for restoration of remaining teeth as required
Preventive advice and tx
Assess potential for post tx across difficulties e.g. trismus, microsomia
Short term treatment side effects of cancer on the oral cavity?
Mucositis: inflammation and ulceration of the mucosal lining of the oral cavity
Infection: chemotherapy induced neutropenia makes the pt susceptible to bacterial, viral and fungal infections. Oral candidal infecs are common following chemo or radiotherapy
Xerostomia - dry mouth resulting from a decrease in the production of saliva after radiotherapy
Long term treatment side effects of cancer on the oral cavity?
Altered anatomy - surgical ablation and reconstruction can cause permanent changes in oral anatomy = prosthetic rehab difficult
Rampant dental caries: radiogenic dental caries due to reduced salivary flow and direct radiogenic damage to amelodentinal junction by radiotherapy
Trismus: due to surgical scarring or by radiotherapy induced fibrosis of the masticatory muscles
Mastication difficulties: if a significant number of opposing pairs of teeth are lost
Osteoradionecrosis: Hypovascularity and necrosis of bone followed by trauma induced or spontaneous mucosal breakdown = non-healing wound
Xerostomia - challacombe to measure degree of dry mouth
What can reduce the risk of xerostomia and potentially osteoradionecrosis after cancer tx?
IMRT
Intensive modulated radiotherapy
Prevention when a pt is having cancer tx?
Maintain good oral hygiene by effective toothbrushing and flossing
Dietary advice with regard to caries prevention
Daily topical F application (duraphat) in custom made trays or brush on. Daily F mouthrinse
Daily use of GC tooth mousse TM containing free calcium
Saliva replacement therapy/use of frequent saline rinses
Jaw exercises to reduce trismus (therabite)
Aetiology of head and neck cancer?
Cigarettes Alcohol Lifestyle Genetics Virus Hormones
Rehab - soft tissue reconstruction and mandibular reconstruction?
Soft tissue reconstruction: Radial forearm flap Anterolateral thigh flap Rectus abdominus Flaps based on the scapular
Mandibular recon: Fibula flap Deep circumflex iliac artery flap Scapular flap RFF
Rehab features - who is involved?
Multidisciplinary decision making should include pt, surgeon, dental prosthodontist/restorative specialist
Prosthetic options reduce morbidity of treatment
Reconstructive options should be considered as defect becomes larger and more complex
Choice of reconstruction or prosthetics requires discussion between pt, maxfax technician, prosthodontist, reconstructive team
Implants?
Pre vs post RXT
Primary vs secondary
1st line of care vs care when conventional removable failed
Fixed vs removable ISPs
When to use primary implants?
Where there is continuity of the mandible
In pts who require the prosthetic obturation of significant maxillary defects
Where retention of the obturator is likely to be compromised
In pts undergoing rhinectomy or orbital exenteration
Types of head and neck cancer?
Oral cavity - Floor of mouth - Anterior 2/3 of tongue - Alveolus - Retromolar trigone - Hard palate Nasopharynx Oropharynx Larynx - supraglottis/glottis/post cricoid Hypopharynx Sinuses
Pathology of head and neck cancer?
SSC 90% Adenocarcinoma Small cell carcinoma Sarcoma Lymphoma Skin - SS C - Basal cell carcinoma - Malignant melanoma - Merkel cell tumour
What does the oncologist need to know?
Type of cancer
Stage of cancer
Fitness of pt
Pt wishes
Investigations needed for oral cancer?
Clinical examination Blood tests Examination under anaesthesia Biopsy Imaging - Of primary: MRI, CT scan - Potential sites of metastatic disease: FDG pet scan, CT scan thorax/CXR
Classification of cancers?
Types of cancer cell
- Glandular = adenocarcinoma
- Skin/mucosa = SS carcinoma
- CT = sarcoma
- Small cell = small cell carcinoma
Grade
- Degree of differentiation, usually G1-3
TNM staging
- T = Size of tumour
- N = spread to lymph nodes
- M = spread to distal organs
HPV features?
DNA Virus
Orogenital transmission
Causes cervical and oropharyngeal SCC
Considered a distinct disease entity
- Younger pts <50yrs
- Non smokers and reduce alcohol exposure
Improved response to chemoradiation
Overview of head and neck cancer management?
Aim = Maximise loco-regional control and survival with minimal functional damage Multidisciplinary approach Early nutritional assessment Dental assessment Speech and language assessment Psychological support
Tx for early stage I-II disease?
Single modality approach
Favourable prognosis
Exception = nasopharynx (chemo and radiotherapy potentially)
Tx for late stage III-IV, M0 disease?
Majority of workload Requires multidisciplinary approach Potentially curable Significant sequelae - acute and late In oral cavity usually means combined treatment surgery and chemo RT
What is radiotherapy?
Radiotherapy features?
Use of x-rays (ionising radiation) to treat cancer
Energy is higher in a therapeutic setting as opposed to diagnostic setting
Diagnostic x-rays up to 150kV
Therapeutic photons - 80kv-20MV
Amount of radiation absorbed by the tissues is called the radiation dose
Unit of RT = a gray (Gy)
Given in up to 50% of cancer patients in the UK
How does radiotherapy work?
Ionising radiation interacts with water molecules forming free radicals = DNA damage = malignant and normal cells damaged
Damage to normal cells = side effects of radiotherapy
Normal cells can repair if tolerance not exceeded
Oxygen dependent
What to consider prior to radiotherapy?
Nutritional requirements - Feeding tube Dental assessment - Dental assessment and tx Speech and swallowing assessment - Mouth and jaw exercises
How is radiotherapy delivered to head and neck?
- Immobilisation device made - Perspex head shell
= Minimises movement during RT and ensure accurate reproducibility in tx set up
= Reference marks - Localisation of tumour volume
- Clinical exam, radiology and knowledge of possible routes of spread
- CT scan or x-ray fluoroscopy - Defining target volume and critical structures
- Includes tumour volume plus a margin of normal tissue
- Critical structures include spinal cord, brain stem, eyes - Define RT fields and tx plan
- Prescribe dose and fractionation schedule
- Verification during tx = ensures fields are accurate
- Review of pattern during tx
- Nutrition = weekly dietetic review
- Commencing PEG nutrition
- Side effects
Doses of RT?
Small volume e.g. T1 N0 larynx or oropharynx:
- Safe to treat with larger fraction size over shorter period of time
Standard volumes of all H&N sites
- Radical - 66-70Gy in 33-35 fractions
- Post op/adjuvant - 60Gy in 30 fractions
Palliation (larger doses as larger doses give worse long term effects but pt not there to experience them)
- Generally 30-45Gy in 10-15 fractions
- Generally give >2Gy/size
Side effects of RT?
Early (acute)
- Develop during or shortly after RT
- V common
- Nearly always resolve
- Nausea, oedema
- Skin redness
- Mucositis, ulceration, reduced state, dysphagia
- Sticky, dry saliva
- Hair loss
- Sore swallowing
Late (chronic)
- Develop months to yrs (>40yrs) after RT
- V rare
- Irreversible and often severe
- Skin necrosis, fibrosis
- Permanent hair loss
- Reduced vision
- Renal failure
- Hypothyroidism
What makes primary disease and lymph node disease at a high risk of recurrence?
Primary disease
- Involved or close margins
- Advanced T stage
- Lymphovascular invasion perineural invasion
LN disease
- Extracapsular spread
- LN >3cm in size
- > 1 LN level involved
- > 2 LN involved
What is chemotherapy good for?
Pt needs to be reasonably fit Useful in palliation of symptoms - Pain - Difficulty with speech/swallowing - Halitosis due to tumour - Ulcerating tumour/nodal mass
Prolongs life by 10 weeks
Utreated medial survival = 4 months
Palliative RT?
Used to improve QoL in pts with recurrent, locally advanced or metastatic disease
- Bone and brain metastases
- Where cure is not possible
- Where pt is not fit to receive radical RT
- Compression of vital structures
Intent is to relieve symptoms and minimise side effects from tx
- May prolong survival
- Small no of total fractions (sessions)
- Relatively low doses
Radiotherapy?
Very useful for fungation, bleeding, pain Re-treatment Dose - Few fraction 5-15 - Palliative dose (reduced toxicity)
Future directions for RT?
Improve dose to targets
Reduced toxicities
New drugs
- Immunotherapy to improve cure rate in addition to chemoradiotherapy and for Palliative tx
