• They arise from mucous glands of upper aerodigestive tract and majority is malignant.
• Commonest site is on hard palate followed by lip and retromolar region.
• Commonest type is adenoid cystic carcinoma.
• It usually presents as a firm mass which later undergoes necrosis and ulceration. It may invade adjoining soft tissues, bone and nerve.
• Treatment is wide excision with plastic reconstruction.
Investigations for Salivary Gland Tumors Radiological Evaluation
• Diagnostic imaging is not required routinely.
• Plain X-ray, USG and sialography have no definite role in salivary tumors.
• CT scan and MRI are good for evaluation of malignant masses that are deep seated and fixed.
• CT scan and MRI help in defining location and extent of tumor, evaluation of neck nodes.
• Bone destruction is best seen on CT scan.
• MRI is useful in detecting perineural invasion, intracranial extension of tumor and detecting deep lobe parotid tumors.
• PET scan is superior to CT and MRI in detecting local recurrence and distinguishing it from past treatment fibrosis.
Cytopathological Diagnosis
• Preoperative tissue diagnosis is not required in discreet parotid swelling.
• FNAC is done when there is high clinical suspicion of malignancy.
Surgery is modified if report is lymphoma. In such case, only incision biopsy is done instead of tumor excision so as to grade the tumor.
If report is Warthin’s tumor in an old patient, the treatment is conservative (no surgery).
FNAC is also useful in recurrent and inoperable tumors for planning radiotherapy as initial treatment.
• Open biopsy is not done routinely due to risk of injury to facial nerve and spreading of tumor cells.
Biopsy is indicated in following conditions:
Repeated FNAC inconclusive in a hard fixed mass.
In case of lymphoma for tumor grading.
Treatment of Salivary Gland Tumors
• Benign and slow growing neoplasm confined to superficial lobe of parotid gland is treated with super-ficial parotidectomy with facial nerve conservation.
In deep lobe tumors, first superficial parotidectomy Fig. 15.13: Rapidly growing and fungating parotid tumor in
a child—high grade mucoepidermoid tumor
Fig. 15.14: Tumor left submandibular gland
with identification of facial nerve is completed. Then with blunt dissection, deep lobe tumor is removed from in-between nerve branches.
• Malignant and high grade parotid tumors require superficial/total/radical parotidectomy with or without sacrifice of facial nerve depending on tumor extent.
Radical parotidectomy may include removal of whole parotid gland with facial nerve, adjoining muscles (masseter, pterygoids) and mandible.
Most important aim of surgery in malignant tumor is “To achieve clear margins of resection”.
Clearance of surgical margins can be confirmed by intraoperative frozen section of the excised specimen (Box 15.6).
Box 15.6: Frozen section evaluation
• Confirms neoplasm (benign vs malignant)
• Accuracy 80-90%
• Confirms margin clearance
• Lymph node assessment for metastasis
If biopsy of resected specimen even in radical parotidectomy shows positive margins for tumor, there is high-risk of recurrence and decreased survival (Figs 15.15A and B).
On the other hand, if surgical margins are negative even in superficial parotidectomy, it is adequate.
Thus more surgery does not improve survival.
Superficial Parotidectomy (Box 15.7) Important steps of surgery are:
• ‘Lazy S’ incision is given which extends from preauricular to mastoid and then in cervical region.
• Skin flaps are raised to expose parotid gland anteriorly and sternomastoid and posterior belly of digastric muscle posteriorly.
• An avascular plane is developed in preauricular area anterior to mastoid tip requiring division of greater auricular nerve.
• By further dissection, facial nerve trunk is identified with the help of various anatomical landmarks (Box 15.8).
Box 15.8: Anatomical landmarks for facial nerve identification
• Tragal pointer (Tragal cartilage points towards nerve)
• Nerve lies deep and medial to tip of mastoid process
• Posterior belly of digastric muscle (lies just inferior and parallel to nerve)
• Styloid process (lies medial and anterior to nerve)
• Bipolar cautery is used for hemostasis to prevent facial nerve damage.
Figs 15.15A and B: Recurrent malignant parotid tumor after superficial parotidectomy (lateral and frontal views);
previous biopsy report revealed positive margins for tumor
Box 15.7: Superficial parotidectomy
• Treatment for pleomorphic adenoma
• Superficial lobe along with tumor is removed
• Facial nerve branches are identified and preserved
• Avoids tumor spillage and removes pseudopodia
• Simple enucleation will leave behind residual tumor leading to recurrence
• After identification of facial nerve trunk, its branches are dissected towards periphery by dissecting in perineural plane (Fig. 15.16).
• Facial nerve can be traced retrograde as well by identifying one of its branches at periphery.
• The superficial lobe along with tumor is removed in toto.
• The wound is closed over a negative suction drain.
Facial Nerve Management
• Preoperative functional status of facial nerve should be assessed by physical examination and look for any partial or total facial nerve palsy.
• In case of absence of clinical nerve involvement and presence of surgical plane between tumor and the nerve during operation, the facial nerve should be preserved.
• In case of preoperative facial palsy and operative findings of nerve invasion by the tumor, the involved area of nerve should be resected.
• After nerve resection, immediate reconstruction by sural or greater auricular nerve should be done and its success rate is 75%.
• Rehabilitation procedures should be performed simultaneously in form of:
Gold weight upper eyelid implants.
Lower lid tightening.
Static facial slings.
• Details of management of facial nerve palsy are given in Chapter 17: Head Injury.
Management of Neck Nodes
• Neck dissection should be done in node positive cases only.
• Modified radial neck dissection is the preferred technique.
• In high grade tumors with clinically negative neck nodes, frozen section of suspicious nodes should be done.
• There is no benefit of elective node dissection in clinically negative neck.
Role of Radiotherapy
• It is always indicated in high grade malignant tumors for improving local control.
• Area of radiotherapy includes preoperative extent with 2 cm margin.
• In adenoid cystic carcinoma, radiotherapy is also given to named nerve roots up to the base of skull.
• In inoperable tumors, radiotherapy is given for palliation.
• In case of recurrent malignant tumors, if resection is not possible, then high dose radiotherapy is given as:
External beam RT, Neutron RT or Brachytherapy
RT in Pleomorphic Adenoma: Indications
• Deep lobe tumors
• Recurrence after surgery
• Microscopically positive margins
• Significant tumor spillage
Chemotherapy has no proven role.
Management protocol of salivary gland tumors is given in Box 15.9.
Complications of Parotidectomy See Box 15.10.
Frey’s Syndrome
It is also known as gustatory sweating. It is a relatively common long-term complication after parotidectomy.
It results from damage of salivary gland innervation during dissection. There is inappropriate regeneration of parasympathetic fibers, which start stimulating sweat Fig. 15.16: Facial nerve branches exposed following
superficial parotidectomy
glands of overlying skin. As a result, sweating and skin flush occurs during salivary stimulation.
Most of the patients have mild symptoms and improve after reassurance. Less than 10% cases request for the treatment. Frey’s syndrome can be prevented by inserting temporalis fascial flap between skin and parotid bed during parotidectomy.
Treatment is with
• Topical anticholenergic agent (1% Glycopyrrolate).
• Botulinum toxin injection into affected skin.
• Denervation by division of lesser superficial petrosal nerve.
Sjögren’s Syndrome
• It is an autoimmune syndrome causing progressive destruction of salivary and lacrimal glands.
• Primary Sjögren’s syndrome is characterized by presence of dry eyes (keratoconjunctivitis sicca) and dry mouth (xerostomia) (Box 15.11).
• If these features are associated with some connective tissue disorder, it is called as secondary Sjögren’s syndrome.
• Females are affected ten times more than males.
• There is painful enlargement of salivary glands.
• Sialography shows punctate sialectasis.
• Biopsy of minor salivary glands show focal lymphocytic infiltration.
• Treatment is symptomatic in form of artificial tears for dry eyes and oral hydration along with salivary substitutes for dry mouth.
• There is increased risk of developing lymphoma especially in primary Sjögren’s syndrome.
Box 15.11: Xerostomia (dry mouth): Causes
• Dehydration
• Anxiety
• Drugs (anticholenergic)
• Sjögren’s syndrome
• Post RT in head and neck CLINICAL EXAMINATION OF SALIVARY GLANDS
History a. Swelling
i. Most cases present with swelling of the affected gland.
ii. Ask for duration and progress of the swelling.
Box 15.9: Salivary gland tumors—management protocol
Box 15.10: Complications of parotidectomy (5 F)
• Flap necrosis
• Fluid collection (hematoma, infection)
• Facial nerve palsy
• Fistula (salivary fistula)
• Frey’s syndrome
• Others—sensory loss to lower pinna (greater auricular nerve damage)
iii. Commonest cause of parotid gland swelling is pleomorphic adenoma. It is slow growing and may be present for several years. Sudden increase in size of swelling is suggestive of malig-nant transformation.
iv. Commonest cause of submandibular gland swelling is chronic sialadenitis due to stone disease. The swelling is of long duration and increases in size during meals.
b. Pain
i. In acute parotitis there is severe throbbing pain.
ii. In malignant parotid tumor there can be pain in parotid region with radiation to ear lobule due to involvement of greater auricular nerve.
iii. In submandibular sialadenitis, the swelling becomes painful during meals.
c. Fever: High grade fever in acute parotitis, parotid abscess.
d. Discharge
i. Foul smelling purulent (sometime blood stained) discharge in oral cavity is seen in chronic sub-mandibular sialadenitis.
ii. Watery discharge over parotid region is seen in parotid fistula. This follows previous surgery or trauma in parotid region (Box 15.12).
e. Sialorrhea: Increased salivary flow (Box 15.13).
Examination Parotid Gland
• Parotid swelling is usually present below ear lobule.
The ear lobule is raised and retromandibular sulcus (groove between mandible and mastoid process) is obliterated due to the swelling.
• On palpation, look for exact dimensions, surface, consistency, mobility, fixity to overlying skin and underlying structures (Box 15.14).
• If overlying skin can be pinched over the swelling, it means skin is free (Fig. 15.17).
Box 15.14: Clinical findings of parotid gland tumors
Pleomorphic adenoma Adenolymphoma Carcinoma
Surface Nodular Smooth Irregular
Consistency Variable (firm, nodular) Cystic Hard
Mobility Mobile Mobile Fixed
Overlying skin Free Free Fixed
Underlying structures Free Free Fixed
Facial nerve palsy Absent Absent Present
Cervical lymph nodes Not enlarged Not enlarged Enlarged Box 15.13: Sialorrhea (increased salivary flow): Causes
• Stomatitis
• Drugs
• Cerebral palsy
• Cretinism
Fig. 15.17: Testing fixity of swelling to overlying skin by pinching
Box 15.12: Parotid fistula Etiology Superficial parotidectomy
Drainage of parotid abscess Trauma of parotid region
Clinical features Clear watery discharge on cheek, more during meals
Diagnosis Fistulography Sialography
Treatment Mostly heals with conservative treatment,
Excision of fistula tract with ligation of parotid duct
• Fixity to underlying masseter muscle – look for the mobility of swelling and then ask the patient to clinch the teeth so as to contract the masseter muscle. If swelling was earlier mobile and becomes fixed on contraction of masseter muscle, it means the swelling is infiltrating the muscle (Fig. 15.18).
• If swelling is immobile on underlying structures even without clinching teeth, it means it is adherent to underlying mandible as well.
• Clinical examination for facial nerve involvement (see Chapter 17: Head Injury).
• Palpate cervical lymph nodes. Hard lymph nodes are suggestive of metastatic deposits from malignant tumor.
• Examine oral cavity—fullness of lateral pharyngeal wall is seen in deep lobe tumors.
• Examine opening of parotid duct in the vestibule against upper second molar tooth. It may be inflamed in acute parotitis.
Fig. 15.18: Testing mobility of swelling by side-to-side movements
Submandibular Gland
• It is felt as a firm, mildly tender swelling in the submandibular triangle of neck in case of chronic sialadenitis.
• Do bimanual palpation of gland by putting one finger in oral cavity to feel floor of the mouth while other finger feels the submandibular gland from outside (Fig. 15.19). The enlarged gland is bimanually palpable while the enlarged submandibular lymph node is palpable only from outside. Sometimes a hard stone may be palpable in the duct of the submandibular gland.
• Look for the opening of the submandibular duct lateral to the frenulum of tongue that might exude pus in chronic sialadenitis.
• Do examination of all salivary glands on both sides since these might be involved due to autoimmune disease (Sjögren’s syndrome).
Fig. 15.19: Bimanual palpation of floor of mouth