DISORDERS OF THE SALIVARY GLANDS Neoplasms Dr.M.Baskaran Selvapathy S IV

Transcription

1 DISORDERS OF THE SALIVARY GLANDS Neoplasms Dr.M.Baskaran Selvapathy S IV

2 NEOPLASMS A) Epithelial I. Benign Pleomorphic adenoma( Mixed tumour) Adenolymphoma (Warthin s tumour) Oxyphil adenoma (Oncocytoma) Basal cell adenoma II.Malignant 1. Mucoepidermoid carcinoma 2. Adenoid cystic carcinoma 3. Acinic cell adenocarcinoma 4. Papillary adenocarcinoma 5. Squamous cell carcinoma 6. Undifferentiated carcinoma 7.Carcinoma arising from mixed tumour B) Connective tissue tumours Hemangioma, Lymphangioma, Lipoma, Neurofibroma. Lymphoma, Secondary deposits Benign tumour turning malignant 2

3 Diagnosis is made from CT, MRI and FNAC. Open biopsy is avoided for lesions involving the major salivary glands, for fear of dissemination of malignancy and damage to facial nerve. 3

4 Pleomorphic adenoma (Mixed tumour) Commonest tumour of the major salivary glands. More common in parotid. Painless, slow growing, benign tumour of many years duration.firm in consistency. Encapsulated. Bosselated surface. Tiny projections extend through the capsule. After decades, a pleomorphic adenoma can turn malignant. 4

5 Pleomorphic adenoma Microscopically, two groups of cells are found. Epithelial cells proliferate in strands and in a trabecular pattern. Myoepithelial cells proliferate in sheets. Mucoid material resembling cartilage is found in some areas, giving rise to cystic appearance. Pleomorphic adenoma has to be treated by superficial parotidectomy. If the deep lobe is involved, total conservative parotidectomy is indicated. 5

6 Adenolymphoma ( Warthin s tumour, Papillary cystadenoma lymphomatosum) Arises from salivary gland inclusions within lymph nodes of the parotid. Consists of double layered columnar cells lining cystic spaces. It presents as a benign, slowly enlarging soft cystic swelling in the lower pole of the parotid. Frequently bilateral. Common in whites. Only salivary neoplasm which is more common in men. It produces a hot spot in 99Tc m pertechnetate scan. Treated by superficial parotidectomy. 6

7 Oxyphil adenoma ( oncocytoma) Benign slow growing tumour, composed of large cells with eccentric nuclei, granular acidophilic cytoplasm with plenty of mitochondria. Treatment is by simple excision. They do not become malignant and do not recur after removal. 7

8 Mucoepidermoid carcinoma More common in parotid. Variable in aggressiveness. Low grade tumours are soft and cystic, whereas high grade tumours are hard in consistency. Facial nerve paralysis does not occur. Treatment is by radical parotidectomy. 8

9 Acinic cell tumour Occurs in parotid. Tends to be soft and cystic. Composed of cells resembling acini. It can become invasive and can metastasise in regional nodes. 9

10 Adenoid cystic carcinoma (Cylindroma) Poorly encapsulated and infiltrating. It consists of nests of columnar cells arranged concentrically around a gland like space filled with mucin. It infiltrates along perineural spaces and invades medullary bone. Hard and fixed. More common in minor salivary glands. Lymph node involvement and facial nerve infiltration can be seen. This tumour has to be managed by radical parotidectomy. Radiotherapy is advised for inoperable growths. 10

11 Adenocarcinoma of the parotid Management is by total parotidectomy with sacrifice of facial nerve. For high grade tumours, regional block dissection is indicated. Arises after 50 years of age. Rapidly growing painful tumours. Facial nerve and masseter infiltration and regional node involvement are common. Distant metastases can reach lungs. Post operative radiotherapy is given for some tumours like squamous cell carcinoma and cylindroma. 11

12 The facial nerve which is sacrificed can be replaced with a nerve graft from greater auricular nerve. Masseter can be transposed to move the corner of the lip. Lateral tarsorrhaphy can be done to prevent corneal damage. If mandible has been removed, bone grafting is done. 12

13 Chemotherapy Methotrexate and 5 FU are used in some aggressive tumours. Cyclophosphamide can be used for local infusion through a catheter inserted through the superficial temporal artery. 13

14 Superficial parotidectomy This is the most common procedure for parotid tumours. The skin incision is like lazy S shaped, starting just anterior to the ear, curving behind below the ear, reaching the mastoid and then extended below along the anterior border of the sternomastoid.skin flap is raised superficial to the parotid fascia up to the anterior border of the gland. Then the posterior border of the gland is defined, allowing identification of the facial nerve above the posterior belly of the digastric muscle.the facial nerve lies 1 cm deep and inferior to the triangular cartilage of the external auditory canal.once the trunk of the facial nerve is identified, it is followed anteriorly dissecting all the branches. Thus, the entire superficial lobe is removed. The wound is closed with a suction drain. 14

15 Radical parotidectomy This procedure is indicated for high grade tumours with facial nerve involvement. It includes removal of both lobes of the parotid, masseter and sectioning the facial nerve. When regional nodes are involved, block dissection is combined. 15

16 16 Adenocarcinoma of SM gland

17 Pleomorphic adenoma of 17parotid

18 Pleomorphic Adenoma of SM 18gland

19 Pleomorphic Adenoma of SM gland 19

20 Superficial parotidectomy incision 20

21 21 Superficial Parotidectomy

22 Superficial Parotidectomy 22

23 23 CT of a deep lobe tumour