Evaluation of the perioperative safety and feasibility through MDT
Currently, our hospital “Blinded for review” has established MDT, whose core is the Department of Otorhinolaryngology, combined with the Departments of Radiology, Radiotherapy, Neurology, Psychiatry, Anesthesiology.
Radiotherapists, radiologists, and otorhinolaryngologists evaluated the tumor control situation to exclude tumor residue, local recurrence, and distant metastasis
According to the Chinese Society of Clinical Oncology (CSCO) clinical guidelines for the diagnosis and treatment of NPC, nasopharyngoscopy and nasopharyngeal and neck magnetic resonance imaging (MRI) scan were employed to assess the local lesions. Besides, chest computed tomography (CT) scan, abdominal ultrasound or upper abdominal CT, whole-body bone scan, and detection of Epstein-Barr virus (EBV) DNA copy number in peripheral blood were used to exclude distant post-treatment metastases. When necessary, PET-CT examination should be considered.2
Radiologists and otorhinolaryngologists assessed the severity of ORNTB and otitis media
ORNTB was characterized as either localized or diffuse based on Ramsden classification: 1) localized type: mostly limited to the external auditory canal (EAC) without invading the mastoid bone of the middle ear; 2) diffuse type: predominantly diffuse necrosis of the temporal bone with a high risk of involvement of adjacent structures, in particular the brain, labyrinth, and the facial nerve and to a lesser extent the temporomandibular joint and the parotid gland.10-13 Based on the Ramsden classification, the surgeons and the radiologists planned the application of three different surgical methods by assessing the intactness of the tympanic membrane (TM) and the thickness and integrity of the cortical bone of the posterior and upper wall of the EAC through the temporal bone CT thin-layer scan on the horizontal section from the facial recess to the base turn of cochlea.
Radiologists diagnosed radiation encephalopathy (REP) and assessed the severity of REP; neurologists and psychologists evaluated patients’ cognitive function and psychological status.
Focal cerebral radiation necrosis, which is a type of REP, can occur after incidental irradiation of the brain during NPC treatment.14 The diagnosis of REP is based mainly on NPC radiotherapy history, imaging examinations, clinical symptoms, and cognitive functions. However, the clinical presentation of focal radiation necrosis is a subacute space-occupying lesion, which is nonspecific. Therefore, imaging examinations, such as standard MRI scans, are the main diagnostic methods for REP (Fig. 1).15 The radiologists diagnosed REP and assessed the severity of REP by MRI. Meanwhile, neurologists and psychologists assisted in judging whether epilepsy and cognitive dysfunction caused by REP were contraindications.
Anesthesiologists should evaluate patients’ perioperative situation and the risk of anesthesia.
One of the most common complications after radiotherapy for NPC is limitation of the mouth opening, which increases the difficulty of endotracheal intubation and thus increases the risk of anesthesia. The anesthesiologists used the modified Mallampati scores to divide the patients into four classes. Nasotracheal intubation should be considered in grades III and IV patients, whereas orotracheal intubation was applied in grade I and II patients.16
Otorhinolaryngologists and audiologists evaluated the patients’ remaining hearing and speech abilities and predicted the postoperative results.
All patients underwent preoperative audiological examination evaluation for cochlear implant candidacy. Intraoperative audiologists routinely performed neural response telemetry (NRT). Postoperative routine reexamination of temporal bone CT was conducted to confirm the electrode’s position in order to exclude the possibility of electrode fracture, partial electrode implantation or implantation failure.