Stanford Head and Neck Center
Salivary Gland Program
Benign Salivary Gland Conditions & Treatments
Benign salivary glad tumors (i.e. Pleomorphic adenoma)
Cysts (mucocele, sialocele)
- Minimal invasive (retrograde)
- Awake parotidectomy (local anesthesia)
Botox injection for Frey's Syndrome (office procedure)
Minor Salivary Gland Operations
Benign salivary gland tumors (neoplasms)
The majority of salivary gland tumors are benign. These are not cancers: they do not generally invade adjacent tissues or metastasize, but they can continue to grow and become deforming. These tumors are usually best removed, though there is no urgency to do so. A pleomorphic adenoma has a small potential to transform into a malignancy over decades.
- Pleomorphic adenoma (a.k.a. benign mixed tumors)
- Warthin’s Tumor (Papillary cystadenoma lymphomatosum)
- Monomorphic adenoma
- Canalicular adenoma
- Sebaceous adenoma
- Ductal papillomas
- Facial nerve neuroma
Pleomorphic adenoma (a.k.a benign mixed tumors) is the most common salivary gland tumor. They are slow-growing tumors often seen in the parotid glands (located in the cheeks). They are best surgically removed as there is a 1% chance of malignant transformation into a cancer (carcinoma ex-pleomorphic adenoma), but timing of surgery is a discussion with the patient: there is no urgency. These tumors may be clinically monitored, monitored for growth, especially in older patients or those with significant other medical problems. In younger patients, in addition to the longer potential for malignant transformation they can grow to a large size.
The parotid glands are the largest salivary glands and located on either side of the cheek in front part of the ear to the mid cheek and from the cheekbone to the lower edge of the jaw. Critical in surgery is preservation of the facial nerve that exits the skull below the ear and passes into and through the parotid gland as it divides into about five branches that go on to and innervate the muscles of facial expression (forehead wrinkle, eye closure, moving nose, and smile). The facial nerve separates the parotid gland into deep and superficial components (sometimes referred to loosely as “lobes” though the gland is one gland and not separated into components). The majority of pleomorphic adenomas are a single mass in the superficial part of the parotid, although a larger tumor may push nerve branches aside without invading the nerve.
Parotidectomy for Benign Parotid Salivary Neoplasms:
- Small well-camouflaged incisions for limited parotidectomy
- Retrograde dissection of facial nerve reduces risk to nerve
The most common operation for pleomorphic adenoma is a superficial parotidectomy consisting of the removal of the outer part of the parotid down to the level of the facial nerve branches. During this traditional parotidectomy, the surgeon makes an incision (facelift incision or a incision in a skin crease that extends to the earlobe and usually in front of the ear) and retracts the parotid away from the ear and finds the facial nerve close to its exit from the skull. The nerve is followed forward (antegrade technique) and the tumor and the outer part of the parotid is removed. This can leave the patient with facial hollowing (from the volume loss) and places the branches of the facial nerve at risk for temporary weakness and potential paralysis. This extensive a procedure may be unnecessary as there is no oncologic benefit to removing this much parotid.
Minimally Invasive Retrograde Parotidectomy
Pleomorphic adenomas and other benign tumors (and most malignant tumors) present as a single tumor in a localized part of the gland and are amenable to removing less tissue via a minimally invasive retrograde parotidectomy. This technique traces only the involved branches of the facial nerve backwards towards the common trunk of the facial nerve. Minimally invasive retrograde parotidectomy allows for smaller incisions, without compromising the removal of the tumor with a cuff of normal parotid tissue to the extent possible. The risk of facial hollowing is less as the entire outer part of the parotid is not removed. More important, this minimally invasive procedure reduces the risk of global facial nerve paralysis because only the branches that are near the tumor are dissected. The operation takes less than 2 hours and the patient may be discharged on the same day (outpatient) or the next day unless they are traveling from long distances or require monitoring of other medical issues.
Long term monitoring is advisable as there is about a 5% rate of recurrence over time regardless of which parotidectomy approach is done, as long as the surgery adequately removed the tumor. Often recommended is a post-treatment baseline MRI several months after surgery, and depending on the physical exam from time to time thereafter.
Recurrences are more difficult to treat. Revision surgery is technically more challenging than initial surgery as scar tissue makes dissection of the facial nerve far more difficult. In addition recurrences of pleomorphic adenoma may occur as multiple masses. A tumor board discussion should occur to review the options that include surgery, possible radiotherapy, or monitoring without intervention. Some patients have had surgery closer to home and seek consultation at Stanford for recurrent disease.
Stanford is a high volume center with over 100 parotidectomies annually, and a weekly head and neck tumor board. This experience allows for thorough discussion of options, reduced operative time, and improved cosmetic and facial nerve outcomes. Once recurrent, the risk for subsequent re-recurrence is also higher. For these special cases we sometimes use the operative microscope to provide magnification of the delicate nerve among the dense scar tissue during the operation.
Salivary stones can block the outflow of saliva in the parotid and submandibular gland leading to severe symptoms of recurrent swelling and pain.
Sialendoscopy is a diagnostic and therapeutic modality used to remove salivary stones, dilate strictures, and manage chronic reactive sialadenitis.
Conditions treated with sialendoscopy:
- Dry mouth (e.g. Sjogren’s disease, radioactive iodine-induced)
- Salivary Stones
- Chronic Sialadenitis
Sialendoscopy is used as a diagnostic and therapeutic modality to remove salivary stones, dilate strictures caused by radioactive iodine, and manage chronic reactive sialadenitis.
Salivary stones can block the outflow of saliva in the parotid or submandibular gland leading to severe symptoms of recurrent swelling and pain.
Chronic reactive sialadenitis can be caused by many conditions including medication induced dry mouth, Sjogren’s syndrome and other systemic conditions. Often the saliva is thickened and slug is formed which can block the pathway of saliva from the glands to the oral cavity. This blockage can be diagnosed and treated by sialendocopy and prevents further long-term damage to the saliva glands.
We use a 0.8 mm endoscopic camera to evaluate the salivary drainage pathways and remove stones using a 1.3mm sialoendoscope under direct visualization. This procedure is outpatient with no incisions on the face.
Sometimes sialendoscopy is used to dilate strictures in the salivary duct formed as a complication of receiving radioactive Iodine therapy for thyroid cancers. The strictures identified endoscopically are dilated to alleviate the symptoms and prevent further damage to salivary glands.
Chronic reactive sialadenitis can be caused by many conditions including medication-induced dry mouth, Sjogren’s syndrome, and other systemic conditions. Often the saliva is thickened and slug is formed which can block the pathway of saliva from the glands to the oral cavity. This blockage can be diagnosed and treated by sialendocopy and prevents further long-term damage to the saliva glands.
Minor Salivary Gland Operations (in the oral cavity)
- Lower lip biopsy to confirm the diagnosis of Sjogren’s syndrome
- Transoral and transcervical approaches to a ranula