Approach To Salivary Tumours Flashcards
Types of adenomas of the salivary gland
- pleomorphic adenoma
- adenolymphoma
- other adenomas
Types of carcinoma of the salivary gland
- acinic cell
- mucuepidermoid
- adenoid cystic
- polymorphous low grade
- ex pleomorphic
- undifferentiated
- squamous
- adenocarcinoma
Histopathological classification of neoplasms of salivary gland
- adenomas
- carcinomas
- non epithelial (vascular, lymphatic, neural origin)
- malignant lymphomas
- secondary mets
- unclassified tumours
- tumour like lesions
Where do parotid tumours most commonly occur
Superficial lobe
What may cause enlargement of parotid lymph nodes
- cancer metastases
- lymphoma
- infection e.g. Tuberculosis
Differentials of parotid tumours
- primary
- lymphoma (especially with HIV)
- metastases
- originating from other local tissue (blood vessels, nerves , fat
Most common beneign parotid tumour
Pleomorphic adenoma
Top 3 parotid malignancies in South Africa
- squamous cell ca of the skin
- mucoepidermoid carcinoma
- malignant melanoma of the skin
Skin cancer of which areas metastasize to the parotid gland
Facial, temporal and auricular skin
Which cancer metastasize to the parotid gland
- skin (most common)
- rarely: cancers of the eye and even distant sites such as breast cancer
Clinical pointers of malignancy of the parotid gland
- Previous skin cancers of the head and neck
- Irradiation to the parotid region many years previously
- Rapid growth
- Pain
- Local invasion
What is the local invasion of parotid malignancy
- Trismus: Invasion of muscles of mastication or temporomandibular joint
- Skin infiltration
- Fixity of the mass to deeper tissues
- facial nerve weakness or paralysis
- Metastases to cervical lymph nodes or lungs
Why may a surgeon request CT scanning of a parotid tumour
To determine the relationship of the tumour mass to the facial nerve (by visualising the retromandibular vein) and to exclude deep extension to the parapharyngeal space
when may fine needle aspiration cytology be useful
- Exclude inflammatory disease eg TB sarcoidosis
- Exclude lymphoma
- Exclude metastasis from skin cancers (these patients require neck dissection)
- patients who do not wish for or are unfit to have surgery
- Inoperable tumours
When is trucut/open biopsy done
- Inoperable cases before committing a patient to radiation therapy
- FNAC is suggestive of lymphoma
Treatment of parotid tumors
All surgically resectable parotid tumours, other than lymphoma are removed by partial or total parotidectomy with preseveration of the facial nerve under general anaesthesia. This is done to remove the tumour and to obtain histological diagnosis
Consequences of parotidectomy
- Scar
- Greater auricular nerve: Permanent loss of skin sensation of the lower half of the external ear and parotid area; may develop neuroma years later
- Facial nerve: Temporary weakness of the face, permanent weakness is unusual
- Frey’s syndrome (gustatory sweating)
What is the postoperative radiation therapy given to parotid neoplasms
- Complete resection: no radiation
- Microscopic residual: Photons
- Macroscopic residual: Neutrons/ photons
What is the follow-up for patients with salivary tumours
Patients need to be followed up lifelong and require an annual CXR
Other than neoplasm, what are other causes of enlarged submandibular glands
- Sialolithiasis
- Sialadenitis
- Enlarged submandibular lymph nodes
How do differentiate between an enlarged lymph node and enlarged submandibular gland on bimanuel examination?
With one finger on the floor of the mouth and the other on the skin overlying the mass:
- Lymph node: Palpable with the outside finger
- Enlarged gland: Palpable with both fingers
Which nerves pass close to the submandibular gland
- Hypoglossal
- Lingual
- Marginal mandibular nerves
How do sublingual gland neoplasms present
Smooth or ulcerated mass in the anterior floor of the mouth, just behind the mandible
How should a sublingual neoplasm be treated
Mass should be biopsied in the oral cavity prior to resection
