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