Salivary gland tumors

frequency GlandsFrequency%Malignant% Parotid6525 Submandibular1040 Sublingual<190 Minor2550

Benign salivary gland tumours Mixed tumour (Pleomorphic adenoma) Monomorphic adenomas –Basal cell adenomas: solid, tubular, trabecular or membranous –Canalicular adenoma –Myoepithelioma –Oncocytic tumours Warthins tumour Oncocytoma Papillary csystadenoma –Sebaceous adenoma Ductal adenomas –Inverted ductal Paillomas –Sialoadenoma papilliferum –Intraductal papilloma.

Mixed tumour (pleomorphic adenoma) Histogenesis –Dual proliferation of ducal and Myoepithelial cells –Myoepithelial cell determines the overall composition and range of appearance of the tumour. –Pluripotential stem cell with ability to differentiate towards epithelial or myopithelial cell lines. Clinical features –Adults:4 th to 6 th decade: M:F=1 –Asymptomatic submucosal mass on the palate, upper lip, buccal mucosa and other sites. –Parotid(85%), submandibular(8%), minor(7%) Histopathology –pseudoencapsulated; Pseudopods of tumor –Variable glandular pattern –Mesenchymal (Myoepithelial differentiation)>myxoid, fibrous, cartilage, plasmacytoid Treatment and prognosis –Excision –Recurrence seen in tumors of major glands. Each recurrence carries a risk of malignant transformation.

Monomorphic adenomas Isomorphic epithelial cell population. Lack neoplastic connective tissue elements that characterize mixed tumors Basal cell adenomas –1-2% of all adenomas –70% in parotid –In minor glands upperlip. palate. buccal mucosa. lower lip –Clinical Slow growing and painless nodule. +/_ multifocal and multinodular years with a male predilection Membraneous adenoma occurs mainly in the parotid. Presents as asympytomatic –Histopathology Types: –Solid: Island sheets of basaloid cells –Trabecular: trabecular cords or tubular epithelial elements –Membraneous: variable sized epithelial islands with foci of normal salivary gland tissue with a PAS+ve hyaline membrane Mitoses rare –Treatment and Prognosis Excision Membraneous tends to recur

Canalicular adenoma –Occurs exclusively in the oral cavity majority in Upper lip –Clinical features 50+. F>m. Upper lip Mobile asymptomatic growth –Histology Bilayered strands of basaloid cells that branch and anastomose within a delicate vascular stroma –Rx and Px Surgical excision with a cuff of normal issue Myoepithelioma –Tumour composed of myoepithelial cells –Majority arise within the parotid gland. Well circumscribed painless mass y m:f=1 –Histology: Plasmacytoid(20%) or spindle cell(70%) or both(10%). –Rx: conservative excision. Within parotid: superficial parotidectomy.

Oncocytic tumours. –Oncocytoma. Predominatly in the parotid –Composed of oncocytes>Large granular acidophilic cell filled with mitochondria.> originate from salivary duct epithelium especially the duct epithelium. –Clinically: solid, ovoid encapsulated lesions<3cm within malor salivary glands. Slow growing. Benign course. DD:oncocytosis:oncocytic metaplasia of salivary duct and acinar cells in normal s.g. Histology:polyhedrall cells with granular eosinophillic cytoplasm and centrally palced nuclei. Sheets of cells with microcystic spaes between cellls. Treatment: conservative. Superficail parodiectmy. Recurrence rarely noted. Malignant chage rare but may occur within an exixting tumour. Papillary cyst adenoma lymphomatosum(warthins tumour). –7% of epithelial s.g. neoplasms –Rare. Predominatly males.50-80y. Association with cigarette smoking. –Thought to originae withoin lymphnodes within S>G. lat aise in areas of LN hyperplasia secondary to chronic inflammation. –Presents as a doughy to cystic mass in inf pole of parotid adjacent to &posterior to the angle of the mandible. –Encapsulated with smooth lobulated surface.. Numerous cystic spaceswith papillary projections lined by oncocytessupported by cuboial cells that overlie llymphoid tissue with germial centers. –Recurrences are rare.

Sebaceous adenoma –Sebaceous differentiation in submandibular and parotid glands giving rise to sebaceous adenoma or sebaceous lymphadenoma. –Rare –Surgical excision. Ductal papillomas –Comprise: sialodenoma papilliferm, inverted ductal papilloma and intradutal papilloma –Rare: arise from the interlobular and excretoy ducts portion of the S.G

Sialoadenoma papilliferum –Buccal mucosa and palate –Painless exophytic papillary lesion originated from the superficial portion of the gland excretory duct. papillary processes forming convoluted clefts and spaces. –The superficial potions lined by squamous epithelium and the deeper portions show cuboidal and columnar cells. –Benign. Mx. Conservative surgery. Inverted ductal papilloma –Rare. Nodular submucosal mass resembling a fibroma or lipoma. Proliferation of ductal epithelium adjacent to intact mucosa. –Intraductal papiloma Arises in deeper part of duct system.