Table 2.

Table summarizing the potential extensions (clustered in vectors of growth) of sinonasal squamous cell carcinomas alongside the recommended resection strategy, based on available literature and authors’ experience.

Primary Subsite	Extension Vector	Involved Structures	Recommended Surgery
Nasoethmoidal	Anterior	Nasal bones, frontal process of the maxillary bone, external nose	Partial/total rhinectomy
	Lateral	Medial orbital bony wall, periorbit, extraconal fat (minimal), medial wall of the lacrimal sac	Orbit-sparing endoscopic resection
		Extraconal fat (non-minimal), ocular muscles, eye, preseptal structures, orbital apex, lateral wall of the lacrimal sac	Orbital exenteration/clearance
	Medial	Nasal septum	Endoscopic resection
	Posterior	Sphenoid sinus, nasopharynx, sella, clivus	Endoscopic resection
	Posterolateral	Pterygopalatine fossa, infratemporal fossa, upper parapharyngeal space	Endoscopic resection
	Cranial	Bony skull base (ethmoidal roof, cribriform plate), dura mater, falx cerebri (minimal), brain (minimal)	Endoscopic resection with transcranial craniectomy w/o subpial dissection
		Falx cerebri (non-minimal), brain (non-minimal)	Cranioendoscopic resection w/o subpial dissection
	Cranio-lateral	Orbital roof, supraorbital dura	Endoscopic resection or cranioendoscopic resection
	Caudal	Hard palate	Inferior maxillectomy
Maxillary	Anterior	Premaxillary periosteum, subcutaneous tissue, skin	Maxillectomy w/o resection of premaxillary skin and rhinectomy
	Lateral	Buccal space, masticatory space	Maxillectomy w/o coronoidectomy
	Medial	Medial maxillary wall, nasolacrimal duct, nasal septum	Maxillectomy w/o septectomy
	Posterior	Pterygopalatine fossa, pterygoid process, masticatory space, upper parapharyngeal space	Maxillectomy w/o endoscopic-assisted delineation of the posterior margin
	Cranial	Maxillary sinus lumen	Subtotal maxillectomy
		Orbital floor, periorbit, extraconal fat (minimal)	Total maxillectomy w/o resection of the periorbit/extraconal fat
		Extraconal fat (non-minimal), ocular muscles, eye, preseptal structures, orbital apex	Orbital exenteration/clearance
	Caudal	Buccal space, buccinator muscle, alveolar ridge/gum, hard palate	Maxillectomy
Frontal	Anterior	Anterior frontal plate, periosteum, subcutaneous tissue, skin	Riedel’s operation
	Posterior	Posterior frontal plate, dura, brain	Riedel’s operation with posterior frontal craniectomy
		Bony skull base (ethmoidal roof, olfactory cleft) and overlying dura	Cranioendoscopic resection
	Caudal	External nose	Partial/total rhinectomy
		Orbital roof, periorbit, extraconal fat (minimal)	Orbit-sparing Riedel’s operation
		Extraconal fat (non-minimal), ocular muscles, eye, preseptal structures	Riedel’s operation with orbital exenteration/clearance
Sphenoid	Anterior	Anterior sphenoidal wall	Endoscopic resection
	Lateral	Lateral sphenoidal wall	Endoscopic resection
	Posterior	Sella, clivus	Endoscopic resection w/o transnasal craniectomy
	Cranial	Mucosa, planum sphenoidale, dura	Endoscopic resection w/o transnasal craniectomy
	Caudal	Sphenoidal floor, nasopharynx	Endoscopic resection