Nasopharyngeal Carcinoma Flashcards
Risk factors of NPC
- EBV infection
- Nitrosamines in salt preserved food
- First degree relative
Epidemiology of NPC
Gender: 3/4 male
Race: majority Chinese
Age: 30-60 years old
- significant socio-economic impact
15-34 yo: 2nd most common cancer
35-64 yo: 3rd most common cancer
WHO histological classification of NPC
Type 1: squamous cell carcinoma
Type 2: undifferentiated squamous cell carcinoma
2a: keratinising undifferentiated SCC
2b: non-keratinising undifferentiated SCC** (most common)
Clinical presentations of NPC
1st most common:
Big, bulky, bilateral neck lumps (DDx: lymphoma) in level II, V
- Mets to cervical LNs
- Firm
- Enlarge –> Central necrosis and abscess formation if left for long time
2nd most common:
Persistent blood stained oral secretions (sputum/saliva)
- Tumour is at post-nasal space so blood from tumour tend to drop down and mix with saliva and sputum
- NO epistaxis/ profuse bleeding
3rd most common:
Unilateral conductive hearing loss or sensation of blocked eyes
- Eustachian tube dysfunction
- NPC compresses eustachian tube causing airway pressure changes –> Otitis Media with Effusion —> Unilateral CHL or aural fullness
Other presentations of NPC
4. Nasal obstruction
5 Unilateral tinnitus
6. CN palsies
- In decreasing order of frequency:
CN 6 –> 5 –> 12 –> 9/10 (patient will be on NGT)
Clinical examination for NPC
- Rigid nasopharyngoscope
- Identify superficial mucosal irregularities
- Other hand freed up for manipulation purposes like suctioning, indirect palpation and biopsies
- Camera-mounted system so others can see
- Performed under LA with nasal spray - Otoscope
- Oral cavity PE (Salivary glands)
- CN PE
Normal post-nasal space
- Mucosal walls smooth
- No asymmetry
- Eustachian tube orifices not obstructed
- Fossa of Rosenmuller well defined bilaterally
*posterolateral outpouching from each side of the nasopharynx that lies posterior to the eustachian tube
Describe an NPC seen
- Exophytic mass that is located at postnasal space posterior to the Eustachian tube orifices
- Ulcerated
- Contact bleeding
Submucosal NPC
Mucosa only slightly irregular
- Small area of heaped up mucosa or
- mucosa of ↑ vascularity which can look normal
*asymptomatic
*incidental finding
Investigations for NPC
Imaging
- for staging purposes
- CT (MRI costly)
- assess nasopharynx, neck lymph nodes - FDG PET-CT
- assess for distant metastasis, augment MRI
- bone scan: bone mets
- cxr: lung mets
- ultrasound liver: liver mets
Others
1. Audiogram and tympanogram (type B)
- check baseline levels as radiation and chemotherapy can cause sensorineural hearing loss
- EBV serology titres
- IgA VCA (Viral capsid antigen) is sensitive
- IgA Ea (Early antigen) is specific
- IgA VCA ≥ 1:40 and IgA Ea ≥ 1:10 is significant - Plasma EBV DNA
- levels should drop after treatment
- used to trace recurrence during post-treatment surveillance
Most common order of distant metastasis from NPC
Bone > Lungs > Liver
GOLD standard for NPC diagnosis
Postnasal space biopsy
- done under direct visualisation using rigid endoscopy under LA
TMN staging epidemiology for NPC
- Majority T1
- Majority N positive
- 2/3 of patients will be stage III/IV when they present
- stage I-III have good outcomes
T staging for NPC
T0: no primary tumour
T1: confined to nasopharynx
T2a: extends to nasal cavity and oropharynx
T2b: extends to parapharyngeal space
T3: extends to sinuses, orbit, skull base, hypopharynx or bony erosions
T4: intracranial involvement, CN palsy
N staging for NPC
N0: no nodal involvement
N1: nodes confined to ipsilateral neck, not > 3cm
N2: ipsilateral nodes > 3cm but not > 6cm, bilateral nodes or contralateral nodes
N3: ipsilateral nodes > 6cm, supraclavicular nodes
M staging for NPC
M0: no distant metastasis
M1: distant metastasis (includes mediastinal nodes)
