most primary head and neck cancers are mucosal lesions , and their mucosal extent can be far better evaluated by the clinician than with ct or mri .
indeed , imaging plays little role in the initial detection and characterisation of head and neck malignancies . however , these tumours do have the tendency to spread submucosally , and this extension into the deeply lying tissue planes is sometimes impossible to detect by clinical examination .
metastatic adenopathies can be identified , sometimes still in a subclinical stage or at places not accessible by clinical examination , such as in the retropharyngeal or paratracheal lymph nodes .
all these findings can profoundly influence the staging and management of the patient with head and neck cancer .
finally , imaging may be used to monitor tumour response and to try to detect recurrent or persistent disease before it becomes clinically evident , possibly with a better chance for successful salvage .
clinically , these lesions may remain asymptomatic for a long period ; at presentation , the disease is often advanced .
the characteristic symptoms are sore throat , referred otalgia and dysphagia , but frequently a neck lump ( due to metastatic neck adenopathies ) is the presenting symptom .
the t - staging is determined by tumour size , tumour extent and the presence of hemilaryngeal fixation .
early piriform sinus tumours may be very subtle ; images obtained during a modified valsalva manoeuvre ( while letting the patient blow against closed lips ) may be helpful .
larger cancers appear as soft - tissue masses , often involving the anterior , lateral and posterior walls of the piriform sinus .
soft - tissue thickening or obliteration of the deep fat planes behind the level of the true vocal cord signifies involvement of the piriform sinus apex .
inferior extension into the postcricoid area may occur submucosally and , therefore , is endoscopically undetectable .
lateral extension may result in extrapharyngeal spread into the neck ; the large neck vessels are then at risk of becoming involved by the primary tumour .
cancer of the posterior hypopharyngeal wall commonly appears as a flat but often widespread mass lesion , which may extend into the lower oropharynx .
cancer originating in the postcricoid area is rare . besides superior spread within the hypopharynx and extrapharyngeal spread , also involvement of the cervical oesophagus may be seen .
these cancers may invade the prevertebral muscles ; ct and mri have a high true - negative but also high false - positive rate in diagnosing such posterior tumour spread .
at least 60% of patients with hypopharyngeal cancer present with clinically positive nodal metastases . in a small minority of patients ,
the primary cancer may at that stage be clinically occult , and may be detected by imaging .
at least 75% will have neck adenopathies at some time during the course of disease .
apart from clinical examination , minimal screening for distant metastasis at first presentation should include chest x - ray .
ct of the chest is the next step when a suspect abnormality is seen on the plain film .
chest ct seems justified in advanced stages of the primary tumour and/or bulky neck disease . in borderline - resectable disease , fdg - pet scan may be considered to exclude occult distant disease .
postcricoid cancer is treated by total laryngopharyngectomy and reconstruction , usually with a pectoralis major myocutaneous flap .
if the tumour extends to the oesophagus , an oesophagectomy is also required . in cancer confined to the piriform sinus or with minimal extension beyond it ,
if the apex is involved , the risk of laryngeal invasion is high and a total laryngopharyngectomy has to be performed .
low - volume hypopharyngeal cancer can be effectively treated by radiation therapy . as in laryngeal cancer , ct ( or mri ) is helpful in assigning patients to a favourable group for radiation treatment , by providing an estimate of tumour volume .
it appears that patients with bulky disease at the piriform apex on imaging have a less favourable local outcome after radiotherapy .
cancer of the cervical portion of the oesophagus is relatively rare , comprising 35% of all oesophageal cancer .
as the lumen of the cervical oesophagus is smaller , these symptoms usually occur earlier than in hypopharyngeal cancer .
oesophagography is used to further define the position and extension of the cancer and degree of obstruction .
ct / mri are useful to further define the intra- and extraluminal extent of the lesion .
the primary drainage nodes of the cervical oesophagus are the paratracheal nodes . as the general lymphatic flow in the upper oesophagus
the incidence of nodal metastasis depends on the length of the primary lesion ; lesions more than 5 cm long show adenopathies in 90% of cases .
distant metastasis is frequently present at presentation , most commonly to the lungs / mediastinum ( in about 30% of patients ) and liver ( about 15% ) .
the high incidence of nodal and distant metastases in patients with cervical oesophageal cancer warrants an extensive pre - operative imaging work - up , including fdg - pet if available . in more than 75% of cases ,
when technically feasible , the cancer is surgically treated ( oesophagectomy ) , including pharyngolaryngectomy when no safe margin with the upper oesophageal sphincter can be obtained .
response to chemoradiotherapy as assessed by serial fdg - pet is strongly correlated with pathological response and survival ; such a correlation was not found for ct and endoscopic ultrasound .
overall , the 5-year survival of cervical oesophageal cancer is low ( between 10 and 20% ) .
   hypopharyngeal and cervical oesophageal cancer are nearly always squamous cell carcinomas .   at presentation ,
hypopharyngeal cancer commonly presents with neck nodal disease , and the primary tumour may be clinically occult .  
subclinical submucosal cancer spread is common in both locations , and may be detected by ct / mri .  
fdg - pet is a useful technique to stage cervical oesophageal cancer , and to assess response to chemoradiotherapy .
hypopharyngeal and cervical oesophageal cancer are nearly always squamous cell carcinomas .    at presentation ,
hypopharyngeal cancer commonly presents with neck nodal disease , and the primary tumour may be clinically occult .   
subclinical submucosal cancer spread is common in both locations , and may be detected by ct / mri .   
fdg - pet is a useful technique to stage cervical oesophageal cancer , and to assess response to chemoradiotherapy .
 hypopharyngeal cancer , and particularly cervical oesophageal cancer , are infrequent tumours . 
 imaging methods assist in pre - treatment planning by better defining the extension of the lesions , by detecting subclinical neck adenopathies , as well as distant metastasis . in selected cases , 
 imaging is also useful for treatment response assessment and surveillance . 
Introduction
Hypopharyngeal cancer
Cancer of the cervical oesophagus
Key points