Presentation on theme: "EVALUATION OF PAROTID SWELLING"— Presentation transcript:
1EVALUATION OF PAROTID SWELLING Dr.K.Kuberan M.SProfessor of surgeryGovt.Royapettah Hospital
2PAROTID GLANDLargest salivary glands lying largely below the external acoustic meatus between mandible and sternocleidomastoid muscle and it also projects forwards on the surface of masseter
3DEVELOPMENT Ectodermal in origin Each parotid is developed during 5th week from angle of primary oral fissure.The groove is converted into tube which forms duct and opens into angle of primitive mouth.
4DEVELOPMENT (contd.)With the growth of maxillary and mandibular process the duct opening is shifted to vestibule opposite the upper 2nd molar tooth.During development the gland lies in between the branches of facial nerve, as development progresses it envelopes the branches.
5PAROTID GLANDSuperficial part(80%)lies over posterior part of ramus of mandibleDeep part(20%) lies behind mandible and medial pterygoidFacial nerve lies between them
6PAROTID CAPSULEThe gland has a capsule of its own of dense connective tissue but is also provided with a false capsule by investing layer of deep cervical fascia.
7Superficial or lateral relations: SkinSuperficial fasciaSuperficial lamina of investing layer of deep cervical fasciaGreat auricular nerve (anterior ramus of C2 and C3)
8Anteromedial relations: Mandibular ramus,Masseter and medial pterygoid muscles
9Posteromedial relations: Mastoid processStyloid processCarotid sheath with its contained neurovasculature (Common and Internal Carotid artery, Internal Jugular vein, vagus nerve)
16Parotid duct Also known as Stensen’s duct Appears at the anterior part of upper border of gland and passes across masseter to traverse buccal fat and buccinator.Runs obliquely forwards for a short distance between buccinator and the oral mucosa and opens upon a small papilla opposite upper 2nd molar tooth.
17Applied anatomy Infections – Very painful due to unyielding nature of capsule.Retrograde bacterial infection may occur from mouth via duct.
36Pleomorphic adenoma Most common parotid neoplasm Median age—Fifth decadeCommon in femalesUsually unilateralSlow growing mass(80%)LobularNot well encapsulatedMalignant degeneration (2-10%)
37Physical examination Mobile Nontender Firm Solitary mass in parotid regionRaised ear lobuleObliteration of retromandibular grooveCannot be moved above zygomatic boneDeviation of uvula & pharyngeal wall towards midine if deep lobe involvedNo facial nerve involvement
38MacroscopyGreyish white in color with possible cyst formation and haemorrhage.
39Histology Mixture of epithelial, myoepithelial and stromal components Epithelial cells:nests,sheets, ducts, trabeculaeStroma:myxoid, chrondroid,fibroid, osteoidNo true capsuleTumor pseudopods
40Dumb-bell tumor Arise from deep lobe Swelling in the lateral wall of pharynxSoft palate displaced to opposite side
41Carcinoma ex pleomorphic adenoma Rapid increase in sizePain and nodularityInvolvement of skin & ulcerationInvolvement of masseterInvolvement of facial nerveInvolvement of neck lymph node
42Carcinoma Ex-Pleomorphic Adenoma 2-4% of all salivary gland neoplasms4-6% of mixed tumors6th-8th decadesParotid > submandibular > Minor salivaryglandRisk of malignant degeneration1.5% in first 5 years9.5% after 15 yearsPresentationLongstanding painless mass that undergoes sudden enlargement
44Warthin’s tumour (papillary cystadeno lymphomatosum) Second most common benign parotid tumour (5%)Most common bilateral benign neoplasm of parotid.Common in lower poleSlow-growing, painless massMarked male predominanceSixth and seventh decadeHot spot in Tc99 scanMalignant transformation rare.
45Gross pathology Encapsulated Smooth/lobulated surface Cystic spaces of variable size, with viscous fluid, shaggy epitheliumSolid areas with white nodules representing lymphoid follicles
46HistologyPapillary projections into cystic spaces surrounded by lymphoid stromaEpithelium: double cell layerLuminal cellsBasal cellsStroma: mature lymphoid follicles with germinal centers
56Clinical features Painless asymptomatic mass (80%) Pain=> perineural invasion (30%)Facial nerve palsy or paresis (7-20%)H/o prior parotid tumor indicates recurrence.
57Clinical features (contd.) Trismus => advanced disease with extension to masticatory muscles or less commonly invasion into TM jointDysphagia => tumour of deep lobe of parotidEar pain=>extension into auditary canalNumbness along Trigeminal nerve =>neural invasion
58Clinical features Hard mass in parotid region Skin ulceration/fixation Fixation to adjacent structuresExamination of external auditary canal for tumor extensionRegional lymph adenopathyBlood or pus from stensen’s ductBulging of lateral pharyngeal wall or soft palate
63Mucoepidermoid Carcinoma Gross pathologyWell-circumscribed to partially encapsulated to unencapsulatedSolid tumor with cystic spaces
64Histopathology Areas of mucous secreting cells Epidermoid and epithelial cells
65Adenoid cystic carcinoma (cylindroma) Poorly encapsulated infiltrating tumorsPropensity to spread along nervesHighly invasive but may remain quiescent for a long timeHighest incidence of distant metastasisLung metastasis are most frequent.Poor prognosis
66Malignant mixed tumors They can arise within a preexisting benign pleomorphic adenoma (CARCINOMA EX PLEIOMORPHIC ADENOMA)They may arise denovo (CARCINOSARCOMA)
67Acinic cell carcinoma Intermediate grade malignancy Low malignant potentialMay be bilateral or multicentricRarely metastasizeMay spread along perineural planes
68Lymphoma Most commonly in elderly females Usually Non-Hodgkins 5-10% of patients with warthin’sEnlarged parotid with a rubbery consistencyEnlarged regional lymph nodes
70Investigations Ultrasound FNAC is the diagnostic MRI is superior in demonstrating benign tumors than CTCT scan/MRI identifies regional lymph node involvement/ extension into deep lobe / parapharyngeal spacePET may be useful in assessing malignant tumors
71Fine-Needle Aspiration Biopsy Efficacy is well establishedSafe, well toleratedAccuracy = 84-97%Sensitivity = 54-95%Specificity = 86=100%
73Surgery (benign tumors) First line of managementsuperficial lobe is involved, superficial conservative parotidectomyIf deep lobe(dumb bell) also involved, total parotidectomy with preservation of facial nerve.Enucleation should be avoided as recurrence rate is highExtracapsular enucleation-warthin’s tumor
74Malignant tumors RADICAL PAROTIDECTOMY Removal of the entire gland,facial nerve and regional lymph nodesResection of all involved structures