p16 negative oropharyngeal squamous cell carcinoma (SCC)

Offer flexible nasoendoscopy/EUA and biopsy.

• If the MDT considers primary surgery is an option, consider minimally invasive transoral or robotic surgical approach for the primary tumour in early-stage disease.

• Avoid mosaic resections other than the specific instance of Trans Oral Laser Surgery (TOLS), where tumour transection is an integral component. Consider surgery to the primary site only when thorough assessment indicates that R0 histopathological surgical margins are probable. Assess definitive margins on the basis of the formalin fixed paraffin embedded surgical specimen and not frozen section findings.

• In lateralised tumours (defined using TNM 8 as a tumour confined to the palatine tonsil/tonsillar fossa/lateral pharyngeal wall with greater than 10 mm clearance from midline, not involving base of tongue or posterior pharyngeal wall and extending onto the adjacent soft palate by less than 10 mm), offer ipsilateral level II-IV neck dissection in well lateralised tumours of the oropharynx (tonsil, ≥1cm from midline) with a N0/N1 neck. Where transoral surgery to the primary site for early disease is deployed accompany the neck dissection with ligation of the appropriate branches of external carotid to reduce postoperative haemorrhage risk.

• In non-lateralised tumours (defined using TNM 8 as a tonsillar/lateral pharyngeal wall tumour that involves the adjacent base of tongue or involves the soft palate by greater than or equal to 10 mm or with less than 10 mm clearance from midline; or as a tumour that arises from a midline structure (base of tongue, soft palate or posterior pharyngeal wall), where tumour extension necessitates significant resection of the soft palate consider flap reconstruction specifically configured to prevent velopharyngeal insufficiency (e.g. ‘Soft Palate Integrity Reconstruction’ with a folded radial forearm flap) and consult surgeons with specific expertise in this scenario.

• For loco-regionally advanced disease (T3/4 N_any or T_any N+) when multi-modality treatment indicated, consider prior to initiating any management:

1. 1. Balance long term control/cure with acute and late morbidity from treatment.
   2. Patient suitability and likelihood of completing whole package of treatment.
   3. Alternative non-curative options.

• Counsel patients carefully on all these factors prior to commencing radical treatment pathway.

• Where the primary tumour abuts or approaches the midline and for N2 disease bilateral neck treatment is indicated.

• For patients with T3 and T4 disease undergoing resection and flap repair patients, counsel patients regarding the likelihood of delayed tracheal decannulation and permanent gastrostomy. Similarly, consider counselling patients where salvage surgery is an option.

Consider prior to initiating any management for salvage:

1. Balance of chance of long term control/cure versus.
2. Likely acute and late morbidity from additional treatment.
3. Likelihood of requiring adjuvant treatment to achieve disease control/cure and patient suitability and likelihood to be offered this depending on patient factors and previous treatment.
4. Alternative non-curative options.

Counsel patients carefully on all these factors prior to commencing salvage treatment pathway.

Salvage surgery is usually undertaken in the context of persistent/recurrent disease after organ preservation treatment.

• Consider salvage neck dissection to the affected nodal basin to patients with N+ve disease who have undergone (chemo)radiotherapy and who are p16 negative and have FDG PET-CT residual avidity in neck nodes at three months post-treatment, with the primary controlled. In p16 positive patients nodal metastases can take longer to respond. In the presence of residual, but declining disease activity (decreased FDG activity, decreased size on cross-sectional imaging), salvage neck dissection may be deferred in favour of continued monitoring via clinical assessment and repeat imaging for up to six months post treatment completion.

• Patients with recurrent/persistent resectable disease at the primary site may be considered for salvage surgery in the absence of distant disease. Consider salvage surgery in the event of recurrence taking into account patient factors including age, co-morbidities, and preferences. Anticipate a high complication rate including fistula formation. The value of elective neck dissection in the salvage setting is uncertain. Anticipate poor swallow functional outcome.
  
  
• Patients with relapse at the primary site as well as regional recurrence have a poor prognosis.
  
  
• Patients with a short disease-free interval have a poor prognosis.

In the palliative setting in anticipation of airway compromise discuss with patients in advance tracheostomy and alternative palliative approaches to respiratory distress. Patients presenting with acute significant bleeding may benefit from interventional radiology procedures and early consultation is advised.