ONLINE EXCLUSIVE Shankar Haran, MBBS; Presentation is key to diagnosing Saniya Kazi, MBBS, FRACP; Saliya Caldera, MBBS, BSc, FRCS (ORL-HNS) salivary gland disorders Departments of Otolaryngology and Paediatrics, Townsville Hospital, Queensland, Australia Initial signs and symptoms offer the best guide to next Shankar.haran01@gmail steps in assessment, testing, and treatment, plus any .com The authors reported no needed referral or multidisciplinary care. potential conflict of interest relevant to this article. aking a diagnosis of a salivary gland disorder can be PRACTICE difficult. Common presentations, such as a painful RECOMMENDATIONS or swollen gland, can be caused by numerous disor- ❯ Use ultrasonography M ders of strikingly variable severity and consequences, includ- for initial imaging of a ing inflammatory, infectious, and neoplastic conditions, for salivary gland. A which treatment can differ significantly, and referral for spe- ❯ Refer patients with the cialty care is sometimes necessary. following findings for further Yet it is the patient’s presentation that can aid you in mak- specialty evaluation: abscess, ing the diagnosis that will guide management. Consider that inflammation unresponsive to medical care, recurrent or acute symptoms often result from infection, for example, and chronic symptoms, suspected chronic or recurrent symptoms are caused more often by ob- neoplasm (for excision), and structive or nonobstructive inflammatory conditions and suspected sialolithiasis. A neoplasms. Diagnosis of an apparent neoplasm, prompted by clinical findings, is made using imaging and fine-needle -as Strength of recommendation (SOR) piration (FNA) biopsy. Acute infection usually resolves with A Good-quality patient-oriented evidence antibiotics and supportive management; calculi that cause B Inconsistent or limited-quality persistent symptoms warrant referral for consideration of patient-oriented evidence stone or gland removal; and malignant neoplasms usually re- C Consensus, usual practice, opinion, disease-oriented quire excision as well as neck dissection and chemotherapy or evidence, case series radiotherapy, or both—calling for multidisciplinary care. In this article, we clarify what can be an imprecise and per- plexing path from the presentation to diagnosis to treatment of disorders of the salivary glands. To begin, see “Geography of the salivary glands,” on page E3, for an overview of the location, struc- ture, and corresponding ducts of the component salivary glands (parotid, submandibular, sublingual, and minor glands). Presentation helps establish the differential Dx Ask: Are the glands swollen? Painless salivary gland swelling has a variety of causes, includ- ing neoplasm, sialadenosis, and the eating disorders bulimia and anorexia nervosa. There is significant overlap of presenta- tions among those causes (FIGURE). Pain accompanying swell- ing is uncommon but not unheard of. CONTINUED MDEDGE.COM/FAMILYMEDICINE VOL 68, NO 8 | OCTOBER 2019 | THE JOURNAL OF FAMILY PRACTICE E1 ❚ Neoplasms. Tumors of the salivary Malignancy. Features of a tumor that gland are relatively uncommon, constitut- raise concern of malignancy include6: ing approximately 2% of head and neck • rapid growth neoplasms; most (80%) occur in the parotid • pain gland, and most of those are benign.1 Al- • tethering to underlying structures or though benign and malignant salivary gland overlying skin neoplasms do not usually present with pain, • firm mass pain can be associated with a neoplasm sec- • associated cervical lymphadenopathy ondary to suppuration, hemorrhage into a • facial-nerve palsy. mass, or infiltration of a malignancy into ad- jacent tissue. The workup of a malignant tumor is Benign tumors. The majority of benign the same as it is for a benign neoplasm: tumors are pleomorphic adenomas of the US-guided FNA, essential for diagnosis, and parotid, accounting for approximately 60% of contrast-enhanced CT or MRI to delineate salivary gland neoplasms.1,2 Tumors localized the tumor. to the submandibular gland are often (in 50% Malignant salivary gland neoplasms of cases) malignant, however.3 usually require excision as well as neck dis- Benign tumors are typically slow- section and chemotherapy or radiotherapy, growing and, generally, painless. On ex- or both, necessitating a multidisciplinary ap- Ultrasonography amination, they are well-circumscribed, proach. Also, there is potential for squamous- is an excellent mobile, and nontender. Patients present- cell carcinoma and melanoma of the head to initial imaging ing late with a large tumor might, however, metastasize to salivary gland lymph nodes; it choice for experience pain secondary to stretching of is important, therefore, to examine for, and investigating a the parotid capsule or compression of local elicit any history of, cutaneous malignancy of possible salivary structures. the scalp or face. gland tumor. Ultrasonography (US) is an excellent ❚ Sialadenosis presents with asymp- initial imaging choice for investigating a tomatic bilateral hypertrophy of the salivary possible salivary gland tumor; US is com- glands—more commonly the parotids and bined with FNA, which is safe and highly rarely the submandibular glands. Swelling is reliable for differentiating neoplastic and persistent, symmetrical, painless, and of nor- non-neoplastic disorders.4 (Avoid open bi- mal tone on palpation. opsy of a neoplasm because of the risk of Causes of sialadenosis include alcohol- tumor spillage.) In patients with suspected ism and, less commonly, diabetes mellitus neoplasm, contrast-enhanced computed to- and malnutrition; some cases are idiopathic. mography (CT) or magnetic resonance imag- An autonomic neuropathy, causing excessive ing (MRI) should also be performed, because salivary acinar protein synthesis or failure of both modalities allow delineation of the tu- adequate secretion, or both, is common to al- mor mass and demonstration of any infiltra- coholism, diabetes, and malnutrition.7 Sub- tion of surrounding structures. sequent engorgement of acinar cells leads to Treatment of benign neoplasms involves clinical parotid hypertrophy. complete excision because, with some tu- Diagnosis is based on history and exami- mors, particularly pleomorphic adenomas, nation, as well as on the findings of US or CT, there is risk of malignant transformation over which will reveal bilateral gland enlargement time. Superficial parotidectomy is the most and increased density. The glands appear common procedure, because most benign dense because adipose cells are displaced by tumors occur in the superficial lobe of the pa- acinar cell hypertrophy; however, end-stage rotid gland. Delicate dissection of the facial changes can result in the opposite appearance: nerve is integral to the operation, although a lucent enlargement caused by fatty infiltra- temporary facial nerve palsy will still occur in tion.2 FNA is unnecessary, unless there is suspi- 5% to 10% of patients undergoing superficial cion of neoplasm, as there would be in patients parotidectomy for a benign tumor, with per- with asymmetrical parotid enlargement, pain, manent injury occurring in fewer than 1%.5 lymph node enlargement, or facial-nerve in- E2 THE JOURNAL OF FAMILY PRACTICE | OCTOBER 2019 | VOL 68, NO 8 SALIVARY GLAND DISORDERS Geography of the salivary glands Parotid duct Parotid gland Sublingual gland Submandibular duct Submandibular gland The salivary glands comprise the major paired parotid, submandibular, and sublingual glands, as well as minor salivary glands that line the oropharyngeal mucosa. Secretion of saliva is modulated by both autonomic and humoral factors. z The parotid gland sits between the mastoid process, the ramus of the mandible, and the styloid process, extend- ing from the external auditory meatus superiorly to below the angle of the mandible and into the neck inferiorly. The gland is surrounded by a tough capsule. Embedded within the gland is the facial nerve, which divides into its 5 branches within the substance of the gland. The parotid (Stensen’s) duct passes anteriorly before turning medially to pierce the buccinator muscle, opening onto the mucous membrane of the cheek opposite the second upper molar. z comprises (1) a large superficial part that fills the space between the mandible and the The submandibular gland IMAGE: ©STOCKTREKIMAGES/SCIENCESOURCE floor of the mouth and (2) a small deep part that wraps around the posterior border of the mylohyoid muscle. The submandibular (Wharton’s) duct runs anteriorly to open onto the floor of the mouth, alongside the frenulum. z The sublingual gland, the smallest of the major salivary glands, lies anteriorly in the floor of the mouth, with many small ducts opening either into the submandibular duct or directly into the mouth. z Basic secretory units of salivary glands are clusters of cells, each called an acinus. These cells secrete a fluid that contains water, electrolytes, mucous, and enzymes, all of which flow out of the acini into collecting ducts. The saliva produced by the parotid is mainly serous; by the submandibular gland, mixed; and by the sublingual and minor salivary glands, mucoid. volvement. In patients with sialadenosis, in ❚ Bulimia and anorexia nervosa. Bulimia contrast, acinar cell hypertrophy alone will be nervosa, the induction of vomiting after binge present. eating, can be associated with bilateral or occa- Treatment of sialadenosis is best aimed sionally unilateral parotid swelling. Anorexia, a at rectifying the underlying medical condi-