Management of Salivary Gland Malignancies Daniel G. Deschler, MD Director: Division of Head and Neck Surgery Massachusetts Eye & Ear Infirmary Massachusetts General Hospital Professor Harvard Medical School No Disclosures or Conflicts of Interest Anatomy Major Salivary Glands Parotid (Serous) Submandibular (Mixed) Sublingual (Mucinous) Minor Salivary Glands 500-1000 throughout aerodigestive tract Sinus, base of tongue, laryngeal 1
Histology Multiple cell types Acinar, intercalated, myoepithelial, Reserve cells Tumorogenesis Tumors traceable to specific cell types Tumor arise from abnl proliferation of progenitor cell 2
Epidemiology Salivary Gland Malignancies 2-5% of head and neck cancers Multiple cell types Divided into high and low grade Importance of site of tumor Parotid -15-20% malignant Submand - 35-50 % malignant Sublingual / Minor - 50-85% malignancy T X T0 T1 T2 T3 T4a T4b Staging - AJCC 7th Ed. Primary cannot be assessed No evidence of tumor <2cm w/out extraparenchymal extension 2-4cm w/out extraparenchymal extension >4cm or with parenchyma extension and no facial nerve involvement Invades skin, mandible, ear canal, and/or facial nerve (Moderately Advanced) invades skull base, pterygoid plates, encases carotid artery (Very Advanced) N0, N1, N2(a,b,c), N3 - Per classic H&N Staging Staging - AJCC 7th Ed. Staging - AJCC 7th Ed. T1 T2 T3 T4a T4b N0 I II III IVa IVb N1 III III III IVa IVb N2 IVa IVa IVa IVa IVb N3 IVa IVa IVa IVa IVb Any T, Any M, M1 Stage IVc 3
Tumor Grade Evaluation High Grade High Grade mucoepidermoid Ca High Grade AdenoCa Adenoid Cystic Ca Carcinoma Ex Pleomorphic adenoma Primary SCCa Low Grade Low Grade Mucoepidermoid Ca Low grade AdenoCa Acinic Cell Ca History Rate of growth, pain Physical Exam Fixation, Cranial Nerve involvement Imaging Tissue Diagnosis Imaging CT Excellent initial evaluation Easily tolerated Easily obtained Bone Excellent, Soft tissue adequate MRI Excellent soft tissue evaluation Assess perineural spread Imaging - Utility Parotid 85% accuracy in defining benign parotid tumor Assess extent (depth) Assess Nodes Other sites Sinonasal, oropharyngeal Perineural spread 4
Cassell, Paul XXXXX Compressed 11:1 Page: 23 of 84 IM: 23 SE: 4 Fine Needle Aspiration High Accuracy Rate 90-95% in numerous studies Minimal risk of tumor spread w/ Fine needle 23-25 gauge Utility of tissue diagnosis Pre-operative planning Extent of procedure Patient understanding of procedure Level of vigilance in surgical approach 5
FNA - Which Lesions Parotid - Yes Pain, VII weakness Submandibular - Yes High rate of malignancy, Pain Sublingual - Yes Usually done transorally Oral / Oropharyngeal - Usually No Mucosa part of resection, Unless mobile in buccal region Derm Punch Parapharyngeal space - Usually No Does not change approach Transoral or CT guidance Surgery traditionally has been the mainstay of treatment Over the last 30 years there has been an evolution validating the efficacy of adjuvant radiation therapy for many lesions 6
Arch Head Neck Surg 1990 46 matched pairs treated at Memorial Sloan Kettering Cancer Center Overall Survival Surg Surg/XRT I,II 96% 82% (NS) III,IV 10% 51% (p=0.015) Appropriate extent of surgery Parotid Tumors Parotidectomy approach Identification and attempted preservation of facial nerve Clearance of tumor with cuff of normal tissue Goal is to clear surgical margins 7
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Facial Nerve Unaffected pre-op Dissect and preserve nerve If nerve close and tumor malignant preserve If nerve frankly involved, verify path (frozen section), sacrifice and reconstruct involved branches 9
Facial nerve - affected pre-op If all branches, prepare for total nerve sacrifice Clear nerve margins (main trunk) May require mastoid procedure If affected in selective distribution, potential exists for selective sacrifice Clear distal and proximal margins Reconstruction Primary nerve grafting Greater auricular Ansa cervicalis Sural Medial antebrachial cutaneous Other 10
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Eye Rehabilitation - Lid Tightening Rehabilitation Eye Oral Commissure Forehead XII -> VII Grafts Crossfacial grafting Free tissue transfer 12
Eye Rehabilitation Gold Weight Surgery can be extensive Temporal bone Auricle External carotid Condyle Mandible Closest margin is the closest Margin Reasonable restraint 13
Submandibular gland Similar approach as Parotid Attention to clear margins Attention to Nerves Marginal Mandibular Branch of VII Hypoglossal (XII) Lingual (V) Sacrifice as needed, reconstruct as possible 14
Neck Dissection N + Disease MRND / SLN N0 Disease No Dissection for low grade lesions (Adenoid cystic ca) Selective neck dissection for High Grade lesions High grade mucoepidermoid High grade adenoca SCCa Neck Metastasis by Histologic Subtype 47/ 407 Occult LN (Cancer: 615-9. 1992) Tumor type % LN + Epidermoid 42% AdenoCa 18% MucoEp 14% Acinic 4% Adenoid Cystic 4% Malignant Mixed 0% Minor Salivary Gland Surgery en bloc resection can be challenging by site Sinonasal, BOT, Larynx, Pharynx Risk of perineural spread Adjuvant XRT often included because of potential close margins 15
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Adjuvant XRT Conventional IMRT Fast Neutrons (ACC) Proton (ACC) Intraoperative Radiation Therapy (IORT) Use in salvage setting of previous XRT 17
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Chemotherapy Largely reserved for recurrent unresectable disease Taxol Head Neck 2006 26% response in mucoep and adenoca 0% response in ACC Use of SCCa regimens for high grade mucoepidermoid Small Series demonstrating better outcome with post-op concurrent Chemo-Rad Grade / Margins Low Grade / Clear Margins Surgery Low Grade / Positive-Close Margins Surgery - XRT High Grade / Clear Margins Surgery - XRT High Grade / Positive Margins Surgery - XRT Grade / Stage Low Grade / Early Stage Surgery Low Grade / Advanced Stage Surgery - XRT High Grade / Early Stage Surgery - XRT High Grade / Advanced Stage Surgery - XRT 19
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