1. Benign salivary gland tumours
Fro a number of reason, benign salivary gland tumours pose special problems for the surgeon & their
patient.
1. At the outset, there is little to distinguish a benign tumour from its malignant counterpart.
The diagnosis is often only made after resection.
2. Preoperative diagnosis by FNAC can be difficult & often inconclusive.
3. The anatomical relationship of the tumour to the facial nerve in the parotid gland is nearly
always intimate & the potential for a significant cosmetic handicap.
Epidemiology & distribution
Salivary gland tumours are relatively uncommon. Fewer than 3% of all neoplasm arise in the salivary
glands. At least 75% of these tumours are benign. For most tumour types there is a slight female
preponderance. All age group are affected from birth to old age.
However, as pleomorphic adenomas predominant overall, the most common age for the
presentation of a benign salivary tumour is in the fourth decade of life.
By far the majority of tumours develop in the parotid gland but a substantial number arise in the
submandibular gland & minor glands of the palate & pharynx.
Within the parotid gland the majority of the tumours develop in the superficial lobe, on other words,
lateral to the facial nerve.
Aetiology
There have been much evidence to suggest that radiation induces salivary gland tumours.( atom
bomb dropped in Japan, salivary gland tumour was increased 2.6 times higher).
Inrecent years, extreme public concern over mobile telephone & development of regional
malignancies. It has been suggested that there is increased risk for brain tumour, uveal melanoma,
salivary gland tumours.
Presentation
Most parotid & submandibular gland tumours develop in an insidious fashion, growing slowly over a
long period of time without causing any other symptom.
1) A very small number causing discomfort by obstructing salivery flow.
Pain is extremely uncommon and if present, usually heralds malignant change. Likewise ,
facial weakness or palsy is virtually never seen unless malignant change has supervene.
The patient with a parotid tumour eventually becomes aware of a firm that is steadily
getting bigger behind the angle of their jaw in the retromandibular region, in front of the
tragus or in the cheek.

2. 2) Deep lobe tumors & those arising from minor oropharyngeal glands displace the tonsil &
palate medially & that are often impalpable from outside.very large parapharyngeal salivary
tumours affect the quality of the patient voice & may interfere with Eustachian tube
function.
3) Tumour those arising from submandibular gland present as swelling in the submandibular
triangle which can be localised more accurately by bimanual palpation of the floor of the
mouth. It is sometimes difficult to differentiate a tumour arising in the posterior aspect of
the submandibular gland from tumour arising from tail of the parotid gland.( an USG is a
simple & quick method of making this distinction when doubt persist).
4) Benign tumours in the minor salivary glands of the oral & pharyngeal mucosa present as firm
submucosal swellings. Ulceration is rarely if ever seen unless there has been local trauma&
in the absence of that, an aggressive malignancy should be suspected.
5) Recurrent tumours are often multiple & it is very easy to underestimate the precise extent
of the disease. Often the tissues in the area are scarred & difficult to palpate accurately &
pinpoint small foci of tumour.
Assessment
Imaging : Detailed imaging of all salivery gland tumours ia neither cost-effective nor necessary. In
the majority, a through clinical examination yields adequate surgical information to permit safe
removal once cosent has been obtained. However for some patients imaging is necessary.
The advantages of USG in the investigation of salivary tumours are frequently exolled by radiologists.
There is little doubt that it can be useful to confirm a clinical suspicion.
There is no doubt that the superior soft tissue definition achieved with MRI makes this the preferred
imaging modality. In the situation where MRI is not available, CT is still a very good substitute.
Indication of CT or MRI
1. Masses confined to the deep lobe of the parotid gland
2. Tumours with involvement of the both the deep & superficial lobes of the parotid
gland(dumb-bell tumours).
3. Parotid tumours presenting with facial weakness , other neural deficit or indication of
malignancy.
4. Congenital parotid masses
5. Submandibular gland tumours with neural deficit or fixation to the mandible.
6. Recurrent disease.
7. Minor glands: tumors of the palate with suspected involvement of the nose or maxillary
antra. All tumours with clinically ill defined margin.

3. Fine needle aspiration cytology
Fine needle aspiration cytology offers at least the possibility of preoperative diagnosis of the parotid
tumours without risk. Using fine needle aspiration, a small area of malignant change in a
pleomorphic adenoma could casily be missed. It would not differentiate follicular from diffuse
lymphoma.
Aspirates of non-neoplastic lymphocytes could come from a variety of lymphocyte-rich lesion such
as W arthin’s tumour, tuberculosis, benign or HIV-associated lymphoepithelial lesion.
Accuracy of diagnosis may be improved by application of immunocytochemistry.
Histopathology & natural history of common benign tumours
Pleomorphic adenoma
The mean age at presentation of patients with pleomorphic adenoma in the parotid gland is 46 years
but they can develop at any time of life.
Overall , there is a slight female predominance(1.4: 1). In the submandibular glands, there is a
greater female predominance(1.7: 1).
80% of parotid pleomorphic adenomas are within the superficial lobe & 20% arise either within the
deep lobe or involve it direct growth. These tumours frequently attain a large size. 11% pleomorphic
adenomas are found in the submandibular gland. In the minor gland, the majority of pleomorphic
adenoma are found in the palate, lip & cheek. They are also occasionally found at other sites such as
the tongue, retromolar fossa, pharynx or tonsil.
The capsule
The capsule of pleomorphic ademona may be thick & fibrous or absent in some part. Focal
infiltration of the capsule is common.
The stroma
The myxoid(mucoid material) stroma of pleomorphic ademona is one of its most characteristic
features. It can form the major part of the tumour & can bulge into the normal gland parenchyma
without any capsule intervening. The mucoid appearance of pleomorphic adenomas makes them
extremely fragile so that they can burst easily at operation. Rupture of the tumour inevitably seeds
the operation field & can result in later recurrence.
The cartilage of pleomorphic adenoma, term pseudocartilage, very occasionally it is the major
component with the whole tumour is very firm.
Calcification or bone formation can occur. Their presence in a salivary gland or a parapharyngeal
mass strongly suggest that the tumour is a pleomorphic.
The cells
It is widely accepted that pleomorphic adenoma are derived from intercalated duct & myoepithelial
cells which differentiate into epithelial & connective tissue structures. The epithelial cells are

4. columnar, cuboidal, squamous or flattened . Arranged in sheets but interspersed by stromal
elements. Squamous metaplasia with keratinisation is common & does not imply malignant change.
There are no certain cellular indications of the likelihood of malignant change. Mitoses are an
occasional feature of benign tumours. High cellularity with mitotic activity, particularly if
associated with increased vascularity & area of necrosis are suggestive of carcinomatous change.
A greater diagnostic difficulty is that of area of atypia within the substance of the
tumour(intracapsular carcinoma). Although such change may later develop frank carcinoma.
Several important points about recurrence
1. As a result of poor encapsulation & tendency to rupture during resection, enucleation has
frequently resulted in subsequent recurrence.
2. It may take more than a decade for them to become apparent, perharps as much as 20
years may elapse after the primary surgery before diagnosis.
3. Recurrences are typically multiple, frequently in the incision scar & often widely separated
from each other. These multiplicity of recurrence tumour nodules clearly makes their
management very difficult. Minute nodules can be hard to detect at reoperation & further
recurrences often follow.
4. The recurrent tumour in some cases forms a fixed bulky conglomerate, removal of which
sometimes requires resection of facial nerve.
5. Finally the incidence of malignant change is greater in recurrent tumours.
It is difficult to differentiate deep lobe tumour to minor pharyngeal gland. Deep lobe tumour
joined to the rest of the tumour by a thin neck.
Warthin’s tumour
This tumour is also known & referred to either adenolymphoma or papillary cystadenoma
lymphomatosum. Warthin’s tumour is the most common monomorphic adenoma. It is account for
14% of all salivary neoplasms & second most common tumour.
The peak incidence of Warthin’s tumour is in the seventh decade but they have been known to
develop much earlier in adult life too. Male : female ratio 1.5:1. Warthin’s tumour appear to be
uncommon in black people.
Warthin’s tumour consists of glandular epithelial component & lymphoid follicles.
These tumours typically grow slowly to form soft, painless swellings, usually at the lower pole of the
parotid gland. A few may undergo rapid expansion possibly caused by cystic change.
Pain may be severe,radiating to the ear, particularly in those where the tumour becomes infar cted.
The combination of pain & sudden increase of size of the mass may be mistaken for malignant
change.
If the tumour aspirates, brownish fluid is strongly suggestive of a Warthin’s tumour.

5. The Warthin’s tumours are also more frequently associated with a second tumour pleomorphic
adenoma. The tumours can be synchronous, metachronous in the same gland or on opposite sides.
Carcinomatous change in Warthin’s tumour may occur.
Myoepithelioma
Myoepithelial cells are a prominent component of pleomorphic adenomas. Tumour derived solely
from myoepithelial cell are rare. Myoepithelioma are considered to be variants of pleomorphic
adenoma that are characterized by overwhelming myoepithelial proliferation. A carcinomatous
variant is also recognized. This tumour has no distinctive clinical characteristics.
Oncocytoma (oxyphilic adenoma)
Oncocytoma are rare tumours. They are predominantly tumours of those over middle age. Women
usually in the seventh or eight decade are more likely to be affected . The parotid are by far the most
frequent site. The tumours are slow growing & may be bilateral. Oncocytoma are benign & excision
are curative.
Treatment
Superficial parotidectomy is adequate treatment for the majority of the tumours.
Total conservative parotidectomy in which all or as much as possible, parotid tissue is removed
leaving the facial nerve intact.
Total parotidectomy , removal of the entire parotid gland & facial nerve is sometimes inevitable
when treating recurrent tumours.
Enucleation or extracapsular dissection is acceptable in those rare situation when tumour is hanging
off the inferior pole parotid gland.
Informed consent
Prior to superficial or total conservative parotidectomy the patient should be warned about
following serious or frequent complications.
Facial weakness: the risk of temporary or permanent facial weakness must be carefully explained as
it has significant impact on quality of life. Neuropraxia usually recovers within 4 to 6 weeks. More
severe injuries cause some degree of degeneration & recovery may never be complete & take 6-12
months oe even longer to take place.
Facial anaesthesia: anaesthesia in the distribution of the greater auricular nerve , over angle of the
mandible, inferior 2/3rd of the pinna is unavoidable.
Cosmetic defects : the cosmetic appearance of the incision rarely causes concern.
Frey’s syndrome: gustatory sweating or flushing is a socially embrassing complication of
parotidectomy. It develops in nearly all patients following surgery to some degree. Application of an
anti-perspirant or local subdermal injections of botulinum toxin.

6. Salivary fistula: it could be speculated that those with a significant volume of residual gland,
extensive cut surface & ligated duct would prone to the complication. Most patients salivery fistula
close spontaneously& settle down over a period of days or weeks.
Operative procdure
The fundamental principle of parotidectomy is exposure of the facial nerve & then removal of the
gland & diseased tissue from around it.
Superficial parotidectomy
Most tumours can be removed through a Lazy S incision. Skin flaps are raised which contain the
subcutaneous tissue lateral to the parotid fascia. The parotid is then mobilized from the cartilage of
the external auditory canal,sternomastoid muscle , digastrics muscle. It is the point of the dissection
that section of the greater auricular nerve becomes necessary.
The facial nerve trunk is then identified. A number of anatomical landmarks facilitate this part of the
procedure.
1. Inferior portion of the cartilage external auditory canal. The facial nerve lies 1cm deep &
inferior to its tip.
2. The groove between the cartilaginous & bony external auditory meatus. The facial nerve lies
immediately deep & inferior to this at its point of exit from the skull. This groove is very easy
to feel.
3. Anterior border of the posterior belly of digastrics muscle. The facial nerve leaves the skull
immediately anterior to the attachment of this muscle. The facial nerve can be exposed by
careful dissection in the area immediately anterior to the posterior belly of the digastrics in
the region of the mastoid process.
In some cases, large or soft tumours immediately overlying the main trunk of the facial nerve, it is
better to locate or identify one of the major branches & dissect centrally or peripherally. The
mandibular branch can be found at the angle of the mandible, lies superficial to facial nerve. The
cervical branch can be located at the point where it pierces the deep fascia below the body of the
mandible. Zygomatic & temporal branches of the upper trunk cross the zygomatic arch anterior to,
the superficial temporal artery.
If the tumour ruptures, the spillage should be contained & the tissue immediately deep to it
removed. In this way , tissue contamination & seeding is minimized.
Total conservative parotidectomy
Occasionally it is necessary to remove the deep lobe of the gland when either tumour has
developed within it or extends into it. Spillage of tumour during superficial parotidectomy is another
indication for local resection of the deep lobe. In this case, parotid tissue must be removed in a
piecemeal fashion.

7. Transpharyngeal approach
After induction og anaesthesia, a preliminary tracheostomy is performed, as this approach includes a
mandibulotomy& there may be significant soft tissue swelling in the immediate postoperative
period.
1. A skin crease incision is made at the level of the hyoid bone extended forward across the
chin to split the centre of the lower lip. The dissection is continued deep to the
submandibular gland until it is free from the surface of the hyoglossus muscle.
2. Attention is then focused on the buccal gingivae which are very carefully elevated from the
underlying bone over chin.
3. Holes are prepared on either side of the proposed, stepped, osteotomy & compression
plates fitted. It is essential that the placement of the compression screws avoid the roots of
the underlying incisor & canine teeth & that plate are accurately bent to the outline of the
mandible.
4. Once fitted, the plates & their screw are removed to one side until the end of the operation.
5. A midline mandibulotomy is then made with a fine oscillating saw.
6. The mandible is then retracted laterally so that the incision can be extended between the
papillae of the submandibular ducts along the floor of the mouth, up the anterior faucial
pillar to the superior pole of the tonsil.
7. During this part of the exposure the lingual & hypoglossal nerves should be identified &
displaced medially.
8. At this stage the exposure is complete & the tumour may be mobilized & removed by blunt
dissection. This technique provides excellent exposure of the medial & superior aspects of
the tumour.
9. After removal of tumour, the mucosa is closed with a single layer of interrupted 3/0 vicryl
suture & mandible secured with the compression plates, the external wound is sutured in
two layers.
Submandibular gland
Unlike the parotid where only a part of the gland is removed, total resection of the submandibular
gland is always indicated for tumours.
Informed consent
The patient should be warned about the following serious or frequent complications.
Damage to the marginal branch of the facial nerve; this may be in either a temporary or permanent
weakness of the angle of the mouth that will be most noticeable on smiling & puckering the lips.
Lingual & hypoglossal nerve damage; neuropraxia of the lingual nerve & hypoglossal nerve is
unusual but possible. Motor dysfunction of the tongue initially impairs articulation & mastication but

8. patient rapidly compensates. Ultimately tongue muscles waste on the side but without further
symptomatic deterioration.
Cosmetic defects; the patient should be reassured that poorly placed skin incision is unlikely to
leave a cosmetically unsightly scar.
Operative procedure
1. The incision is made in or parallel to a natural skin crease approximately 2.5 cm below the
lower border of the mandible & extending for approximately 10cm anterior to
sternomastiod muscle. It is deepened through the platysma muscle & flap developed in the
fascial plane beneath the platysma.
2. Care must be taken in development of the superior flap as the marginal mandibular branch
of the facial nerve runs in the same plane.
3. The nerve enters the neck 1cm in front of the angle of the mandible, loops over the facial
artery &vein 2cm below the lower border of the body of the mandible before sweeping
superiorly to the angle of the mouth.
4. The mandibular branch of the facial nerve can be protected from inadvertent damage by
one of the two manoeuvres.
A) The facial vessels can be transected at a low level on the surface of the
submandibular gland & reflected superiorly. The nerve which lies lateral to the
facial vessels can then be lifted out of the operative field by traction on the
transacted end of the vessels.
B) Alternatively the capsule of the gland can be opened at level of the hyoid bone
& dissection continued beneath capsule. The elevated capsule protects the
nerve in a similar fashion to the first technique.
5. The superficial part of the gland is mobilized by either blunt or sharp dissection & retracted
posteriorly in order to expose the deep portion that lies on the hyoglossus muscle & is partly
covered by the myohyoid muscle.
6. Retraction of the mylohyoid anteriorly, together with posterolateral on the gland, brings the
lingual nerve, duct & more proximal part of the facial artery into the operative field.
7. The lingual nerve appears as a ribbon like band loosely attached to the body of the gland by
a few fibres.
8. At this stage the hypoglossal nerve may be seen inferior & parallel to the lingual nerve.
9. Proximal end of facial artery is usually ligated at this point.
10. The gland is then further mobilized from the hyoglossus muscle & about its duct so that this
may be ligated & transected as far anterior as possible.

9. 11. A small vacuum drain is inserted & brought out through the skin posteriorly. The wound is
closed in two layers.

10. 11. A small vacuum drain is inserted & brought out through the skin posteriorly. The wound is
closed in two layers.