Salivary Gland Program
Head & Neck Center
Benign Salivary Gland Conditions & Treatments
- We provide a comprehensive array of surgical procedures to treat
benign and neoplastic disorders of the salivary glands.
- We specialize in minimally invasive parotidectomy.
- We take a multidisciplinary approach towards the treatment of
malignant salivary cancers.
- We are equally focused on the advanced reconstruction of oncologic
defects to provide function and superior esthetic outcomes.
- Benign salivary glad tumors (i.e. Pleomorphic adenoma)
- Dry mouth/Xerostomia
- Salivary stones
- Frey's syndrome
- Cysts (mucocele, sialocele)
- Minimal invasive (retrograde)
- Awake parotidectomy (local anesthesia)
- Botox injection for Frey's Syndrome (office procedure)
- Minor Salivary Gland Operations
What Are 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
Malignant Salivary Gland Conditions and Treatments
What Are Malignant Neoplasms?
Primary cancers of the salivary gland are uncommon, but not rare. Just as a benign tumor does, they often present as a painless enlarging mass that may or may not be associated with neck lymph node metastases. A diagnosis is generally made possible via a fine needle biopsy (FNA). Imaging (MRI) helps define its extent in the neck. A PET-CT or chest CT may be ordered to assess for distant spread. The stage is defined by the size of the tumor, presence of neck metastases, presence of distant spread (uncommon for most tumors) and whether there is facial weakness. About 20% of parotid tumors are malignant, with higher percentages for children, for the submandibular gland, and for intraoral minor salivary glands.
Types of Salivary Gland Malignancies
Broadly speaking, salivary gland malignancies are grouped into low grade and high grade cancers. Low grade cancers have a very good prognosis, and are often cured with surgery alone. Long-term follow-up is required need to ensure early intervention should there be a recurrence, which can occur years later.
The pathologies listed below are among the more common malignancies seen. They may arise from the parotid, submandibular gland or minor salivary glands. In some instances a cancer in the parotid may have actually spread to an intraparotid lymph node from elsewhere (such as from a facial skin squamous cell carcinoma or a melanoma) or such a metastasis may rarely even arise from farther away. Rarely a tumors may be malignant transformation from a prior benign tumor (as in a carcinoma arising within a prior benign pleomorphic adenoma).
- Acinic cell adenocarcinoma
- Low grade mucoepidermoid carcinoma
(some also describe an intermediate grade, which largely behaves similarly)
- Polymorphous low-grade adenocarcinoma (in palate)
- Epithelial-myoepithelial carcinoma
- Adenoid cystic carcinoma
- High grade mucoepidermoid carcinoma
- Carcinoma-ex pleomorphic adenoma
- Salivary duct carcinoma
- Squamous cell carcinoma (a primary squamous cell carcinoma may theoretically also occur)
- Other metastases
- Lymphoma: arising within gland or involve periparotid lymph nodes
Intervention usually require surgery as first step. A low grade small malignancy may require only surgery, with surgery as described for benign parotid tumors. If in the submandibular gland, the gland is removed; likely along with upper neck nodes, a procedure with few likely side effects. A neck dissection (removal of nodes in the neck) will be done if nodes are involved in either a parotid or submandibular gland malignancy and may be recommended for some high grade tumors where the nodes are at risk.
Irradiation after surgery is recommended for larger low grade malignancies (greater than 4 cm.) and all high grade malignant tumors. Irradiation may include the neck nodes on the same side of the malignancy if either there were nodes involved or nodes are at risk for developing metastases. Chemotherapy may play a role as a radiosensitizer or when there is distant spread. Chemotherapy as a radiosensitizer (making the irradiation possibly more effective) may be discussed within a clinical trial.
The Stanford comprehensive multidisciplinary head and neck tumor board meets weekly to review the imaging and pathology of all new patients (and existing patients with new problems). It comprises of members of different specialties with a common clinical focus on head and neck cancers: head and neck surgeons, medical oncologists, radiation oncologists, nutritionists, speech therapists, radiologists, and pathologists. Individualized treatments options are tailored for each patient, including the applicability of available clinical trials, and are then discussed with each patient.
As with low grade cancers, long-term follow-up is required need to facilitate consideration of intervention should there be a recurrence in the neck of a distant metastasis.
We treat all salivary cancers, including patients that have failed prior treatments. In revision parotid cancers that have been previously radiated, intraoperative radiotherapy may be indicated (irradiation to the area of concern done at the time of surgery, such that the skin in not irradiated and critical structures may at times be able to be shielded).
Facial Nerve Reconstruction
Reconstruction after parotid cancer surgery is an important aspect of any cancer operation. The face is important to a person’s identity. Patients with facial nerve paralysis as a result of a high-grade salivary cancer receive facial nerve reconstruction at the time of cancer operation. Facial nerve reconstruction options include:
- Gold or platinum implant to the upper eyelid
- Lower eyelid tightening
- Static lower face sling
- Masseter transfer to the lower face
- Temporalis muscle transfer to the lower face
- Facial nerve grafting
To restore volume loss (cheek hallowing) after parotid surgery, we provide the following reconstructive techniques:
- Sternocleidomastoid muscle flap
- Free flaps
- Fat grafts
- Digastric flap
- Temporalis or temporoparietal flap
Minor Salivary Gland Operations (in the oral cavity)
- Composite resections of high-grade cancers
Your Care Team
Dimitri Colevas, MD
Harlan Pinto, MD
Beth Beadle, MD
Michael Gensheimer, MD
Quynh Thu Le, MD
Speech and Swallowing Rehabilitation
Heather Starmer, Speech Therapist
Jennifer Kizner, SLP
Monika Kurzymski, RN
Priyanka Shah, PA, the advanced practice provider