Table 1 Key items for radiological assessment of oropharyngeal cancers.
Item | Key information | Implications for surgical treatment | TNM classification15 | |
|---|---|---|---|---|
MRI Multidetector CT | Essential for prognosis. Worse prognosis in HPV − tumors | The larger the size, the greater the probability of having to do reconstruction | ≤ 2 cm: classified as T1. 2.1–4 cm: classified as T2 > 4 cm: classified as T3 | |
Preferentially MRI | Involvement of genioglossus entails a high probability of crossing the lingual septum due to its proximity. Evaluation of floor of mouth involvement, mylohyoid | Predicts the probability of needing neck dissection | T4 HPV+ T4a HPV − or indeterminate | |
Preferentially MRI, contrast-enhanced T1 sequences and T2 sequences Better in coronal slices | Marking of midline. Prognostic indicator for nodal dissemination patterns and impacts survival rates. | Its involvement precludes partial glossectomy and hemiglossectomy. Reconstruction should be considered with flaps. | (Involvement of extrinsic musculature) T4 HPV+ T4a HPV − or indeterminate | |
Preferentially MRI, contrast-enhanced T1 sequences and T2 sequences (coronal slice) | Marking of midline. The risk of bilateral metastasis approaches 30%. | Usually, a relative contraindication to surgery. Indication for transoral surgery | ||
Preferentially MRI, contrast-enhanced T1 sequences and T2 sequences Axial slice. Intraluminal tumor is highly specific | Involvement > 270° is associated with embedding and has a mortality rate nearing 100%. If contact affects < 180°, the likelihood of vascular embedding decreases | In case of surgery, ligation is recommended, although due to the prognosis it is not usually done | T4b in HPV − or indeterminate | |
CT better for cortical bone MRI better for medullar bone | Evaluate mandible, hard palate, and skull base | Early identification will allow marginal or partial mandibulectomy | T4 HPV+ T4a HPV − or indeterminate. In case of involvement of skull base: T4b in HPV– or indeterminate | |
Preferentially MRI | The obliteration of the fatty plane surrounding the cranial nerve, enhancement with or without thickening of the nerve, and the denervation of a group of muscles innervated by the cranial nerve26 | 15–20% lymph node involvement. Propose cervical dissection according to guidelines | ||
Involvement of the lingual surface of the epiglottis28 | Preferentially MRI, contrast-enhanced T1 sequences and T2 sequences Multidetector CT. Sagittal section | Not to be confused with laryngeal involvement | Requires excision of epiglottis; risk of aspirations | T3 |
Preferentially MRI, contrast-enhanced T1 sequences and T2 sequences | Virtual space, usually made up of fat. Implies the involvement of the constrictor muscles | Accessible through transoral surgery like TORS | ||
Dissemination to the larynx30 | Preferentially multidetector CT | Involvement of the epiglottis in tumors at the base of the tongue increases the risk o | The resection could be extended without modifying the field in TORS + TLM | T4 HPV+ T4a HPV − or indeterminate |
Sequences in T1 with contrast and T2 | Identify lateral pterygoid, medial pterygoid, and pterygoid plates31 | Very complex, complete resection by transoral techniques | In case of involvement of lateral pterygoid and pterygoid plates T4b in HPV– or indeterminate o T4 in HPV+. | |
Nasopharyngeal space33 | Contrast-enhanced T1 sequences and T2 sequences | Special attention to the lateral wall | More complex excision, requires multiple techniques | T4b in HPV– or indeterminate |
MRI, contrast-enhanced T1 sequences and T2 sequences PET-CT Multidetector CT Ultrasound (experienced user) | High incidence > 15 mm in jugulodigastric lymph nodes and > 10 mm in other lymph nodes. Cystic adenopathy with a hypodense center indicates HPV-positive SCC | Investigate areas I (base of the tongue), II, III and IV (tonsils) | Classification N |
