Post-Op

Question 1

Indications

Answer 1

Indications: ≥2 nodes positive, ECE, positive margin, LVI, PNI, close margin, cartilage/bone/muscle invasion.

Oral cavity: T2 with ≥5-10 mm depth (no consensus)”

Question 2

Dosing

Answer 2

“66 Gy for positive margin or ECE (SIB to 1.6.-1.8 daily to low risk)
60 Gy to tumor bed, involved neck, dissected neck, and intermediate risk (PNI, LVI, T4, close margin in 30 fx (SIB 1.6-1.8 Gy daily to low risk).
Lower risk area to 50-56 Gy
70 Gy if gross disease still present

Two volume: 60 Gy in 30 fx with SIB 1.6-1.8 Gy daily to lower risk areas”

Question 3

Fields

Answer 3

“CTV neck: in dissected neck, include the retrostyloid space (RSS) down to SCV, plus nodes in Biau guideline. There is growing evidence to omit RT to a dissected neck if pN0 and PET negative (Lowe, Contreras). In undissected neck, follow Biau guidelines.

CTV-P: post-op bed plus 0.5-1.5 cm margin. No consensus. In tonsil, consider omission of primary if treating neck and no indications to treat primary

PNI: Trace nerve to skull base for extensive PNI, named nerve involvement, + or close nerve margin, clinical or radiographic PNI, adenoid cystic. Cover anterograde paths only if suggestions of anterograde spread are present.
ECE: some include adjacent muscle and scar. For suspected ECE in gross node, add 5 mm nodal CTV
Trach: Most always treat. Some only treat if emergent, involved, or subglottic ext. Apply low dose volume/middle dose volume.
Flap: most always include

Careful for post-op larynx and hypopharynx total laryngectomy: the hyoid is gone. (Hyoid is normal border of level V and RP nodes). Compare to pre-op scan for reference.

Question 4

Outcomes

Answer 4

Start 4-6 weeks after surgery, finish in 11 weeks per Ang

“5-yr LRC 80%
5-yr OS 50%”

Question 5

PNI

Answer 5

PNI: Trace nerve to skull base for extensive PNI, named nerve involvement, + or close nerve margin, clinical or radiographic PNI, adenoid cystic. Cover anterograde paths only if suggestions of anterograde spread are present.

“CN V or VII involvement: trace nerve to internal auditory canal at skull base.

Oral cavity: inferior alveolar and lingual nerve –> V3 (masticator space to ovale), XII

Submandibular gland: XII and lingual nerve –> V3

Parotid: VII and +V3 via auriculotemporal nerve

Hard palate: V2 and +VII via greater superficial petrosal nerve and vidian nerve

Lower lip: mental nerve –> V3

Upper cheek: infraorbital nerve –> V2