Otolaryngology
Rhinology
أ م د حيدر السرحان
Sino nasal Tumors:
Pathology:
About 10% of head and neck cancer is sinonasal. It is about double this in
Arabs, the Japanese and Africans. The male: female ratio in series varies
between 1:2 and 1:5. Half of sinonasal cancer arises from the upper jaw, a
quarter from the ethmoids and a quarter from the nasal cavity.
Histologically 50% are squamous cell carcinoma, 15% anaplastic, 10%
lymphomas and about 4% adenocarcinomas.Rarely olifactory neuroma is
also reported. The association between the ethmoidal adenocarcinoma
and hardwood workers is well documented. Workers handling chromate
salts and those involved in nickel refining are at an increased risk of nasal
malignancy. Chronic nasal pathology, including sepsis and Wegener's
granulomatosis, and smoking cigarettes have recently been implicated as
providing an increased risk of squamous cell carcinoma. Human
Papiloma virus genome has been identified and therefore implicated as an
aetiological agent in non-dysplastic and dysplastic inverted papilloma
and seuamous cell carcinoma.
Classification:
Both benign and malignant groups can be classified into epithelial, non
epithelial, odontogenic, and fibro-osseous tumours.
1. Benign.
Epithelial (papilloma, adenoma and inverted papilloma).
Non-epithelial
(fibroma,
haemangioma,
nasal
glioma,
Schwannoma, chon-droma, haemangiopericytoma, chordoma,
meningioma and osteoma).
2. Malignant.
Epithelial (squamous cell carcinoma, adenocarcinoma, anaplastic
carcinoma, transitional cell carcinoma, malignant melanoma,
salivary gland malignancy in particular adenoid cystic carcinoma
and olfactory neuroblastoma.
Non-epithelial (fibrosarcoma, angiosarcoma, chondrosarcoma,
rhabdomyo-sarcoma, and osteogenic sarcomas).
Important benign sinonasal tumours
Inverted papilloma:
originally described by Ringertz, is the most important of this group
forming about 5% of all nasal tumours. Macroscopically there is usually a
papilliferous exophytic mass. Microscopically there are deep
invaginations of epithelium into the stroma, with microcyst formation.
The epithelium retains its basement membrane. Probably less than 2%
undergo malignant change although there may be a synchronous
sinonasal squamous cell carcinoma in up to a further 10%. This
emphasizes the need for careful endoscopic follow up.
Osteomas:
most commonly arise from the frontal region where they may expand
medially to block the frontal recess predisposing to a secondary mucocele
or frontal sinusitis, inferiorly to displace the orbit, superiorly where they
may erode the cribriform plate or posteriorly to erode the posterior wall
of the frontal sinus and impinge on frontal lobe dura. They consist of hard
cortical bone and require excision if symptomatic or enlarging.
Haemangiopericytomas:
may arise anywhere in the sinonasal region and have a spectrum of
aggression, with a propensity to recur many years after apparent cure.
Malignant sinonasal tumours:
Squamous cell carcinoma and adenocarcinoma both usually present at an
advanced stage because their presenting symptoms of epistaxis, nasal
obstruction and headaches occur only with a significant tumour mass.
Further delays may arise because these symptoms are not usually
associated with carcinoma by primary care physicians. Cheek swelling
occurs only when the tumour has breached the anterior antral wall to
impinge on periosteum. It is usually impossible to define a site of origin
of the carcinoma due to its diffuse extent. This may include the cheek,
orbit, nasal cavity and anterior cranial fossa. Five per cent of subjects will
have a metastatic neck lymph node, usually upper deep cervical, on
presentation. This indicates a poor prognosis but not necessarily
incurability. A quarter of patients will die from distant metastases, most
commonly the bronchus. Adenoid cystic carcinoma is particularly
difficult to eradicate because of its ability to spread via the branches of
the trigeminal and olfactory nerves along perineurium. Malignant
melanomas comprise 1% of sinonasal carcinomas and usually arise from
the septum or lateral nasal wall, where the prognosis is reasonable.
Frontoethmoidal and antral malignant melanoma have a much worse
prognosis. There is no relationship between Clark's classification
(penetration of specific skin layers) and prognosis in this region although
the latter is associated with Breslow's classification (thickness of the
lesion in mm). Olfactory neuroblastomas usually arises from neural crest
stem cells, the precursors of olfactory cells, and microscopically
resembles other small cell malignancies such as high grade lymphoma
and anaplastic carcinoma. All ages are affected and urine vanillyl-
mandelic acid (VMA), is not usually detectable. It always involves the
cribriform plate so if resection is contemplated this must be via a
craniofacial approach.
Staging
The UICC staging is as follows:
Tx Primary tumour cannot be assessed.
T0 No evidence of primary disease.
Tis Carcinoma in situ.
Maxillary sinus:
T1 Tumour limited to the antral mucosa with no erosion or destruction of
bone.
T2 Tumour causing bone erosion or destruction, except for the posterior
wall, including extension into the hard palate and/or middle nasal meatus.
T3 Tumour invades any of the following: bone of posterior wall of
maxillary sinus, subcutaneous tissues, skin of cheek, floor of medial wall
of orbit.
T4 Tumour invades orbital contents beyond the floor or medial wall
including apex and/or any of the following: cribriform plate, base of
skull, nasopharynx, sphenoid sinus, frontal sinus.
Ethmoid sinus:
T1 Tumour confined to ethmoid with or without bone erosion.
T2 Tumour extends into nasal cavity.
T3 Tumour extends to anterior orbit and/or maxillary sinus.
T4 Tumour with intracranial extension, orbital extension including apex,
involving sphenoid and/or frontal sinus and/or skin of nose.
Clinical features:
1. Nasal cavity tumours. Epistaxis, nasal obstruction and a mass visible
on nasendoscopy.
2. Frontal sinus. Features are similar to frontal osteomas except the
history is shorter and more rapidly progressive.
3. Ethmoidal. Epistaxis, nasal obstruction and if the lamina papyracea is
breached, proptosis, epiphora and diplopia. Nasendoscopy may reveal
tumour extruding from the middle meatus.
4. Antral. Epistaxis, nasal obstruction, cheek swelling, headache if
blocking the osteomeatal complex and atypical facial pain (suggesting
involvement of the pterygo-palatine fossa or the infra orbital nerve).
Oroantral fistula, ill-fitting dentures, trismus and ethmoidal symptoms
occur with advanced disease.
Investigations:
A high definition CT scan on both bone and soft tissue windows is the
ideal to show soft tissue and bone involvement. A T2 weighted or STIR
sequence MRI scan may distinguish tumour from inflammation, retained
secretions and fat.
Treatment:
Inverted papilloma:
The accurate identification of disease extent with CT and MRI imaging
has allowed the advent of endoscopic resection for inverted papilloma.
Recent studies have demonstrated recurrence rates no higher than with
external approach surgery. There is significantly less morbidity by the
endoscopic approach. The technique allows direct visualization of tumour
and its extent can be accurately identified during surgery. It prevents an
external scar, there is less blood loss and the hospital stay is shorter.
Tumour limited to the anterior ethmoids or isolated middle turbinate or
middle meatal lesion are ideal for endoscopic resection. Recent work has
also shown its application for tumours involving the posterior ethmoids
and anterior wall of sphenoid. In essence provided the endoscope can
visualize the distal extent of tumour during surgery then endoscopic
resection is a reasonable and perhaps preferred alternative to external
approach surgery. Post-operatively endoscopic inspection of the surgical
cavity allows accurate monitoring of patient progress and early
identification of recurrence.
Carcinoma:
There are three main surgical options for carcinoma:
(a) Lateral rhinotomy for tumour limited to the lateral nasal wall, nasal
cavity and ethmoid. An upper limb extension will allow tumour limited
to the frontal ethmoidal region to be accessed.
(b) Total maxillectomy. For antral carcinoma.
(c) Craniofacial resection is indicated when the cribriform plate is
involved or breached.
In general an orbital exenteration is indicated only if tumour breaches
periostium to involve orbital fat. Adjuvant radiotherapy may be indicated
depending on tissue margins. Prognosis by stage is difficult for reasons
already outlined. Overall a five-year survival of 40-50% would be
reasonable.
Follow-up and aftercare:
Ideally an orthodontist should take an impression of the maxillectomy
cavity at operation in order to make a temporary obturator. Further review
allows a fine tuning of the prosthesis to provide a light, comfortable, well
fitting and easily removable obturator. Those who have a lateral
rhinotomy or craniofacial cavity often have excessive crusting in the early
post-operative phase. Glycerine and glucose nose drops and regular
douching with saline will minimize it Follow-up which involves nose
endoscopy to inspect the surgical cavity created or direct inspection of a
maxillectomy cavity after obturator removal, laryngopharyngeal
examination to exclude a second primary and neck examination to look
for metastases should be monthly for the first post-operative year,
bimonthly for the second, quarterly for the third and six-monthly until
five years post surgery. Some surgeons thereafter review annually for a
further five years.