Malignant Salivary Gland Tumors

What is Malignant Salivary Gland Tumors?

Salivary gland tumors are uncommon and complicated growths that can develop in different areas of the salivary glands. These glands are in parts of the mouth and throat, including the parotid, submandibular, sublingual, and minor salivary glands. These tumors can be hard to diagnose and treat due to their diverse origins, appearance under the microscope, growth rates, and characteristics.

In 2005, the World Health Organization recognized 24 different types of malignant, or cancerous, salivary gland tumors. The most commonly found types are mucoepidermoid carcinoma (MEC), acinic cell carcinoma (ACC), adenoid cystic carcinoma (AdCC), carcinoma ex-pleomorphic adenoma (CExPA), and adenocarcinoma. Each of these represents a different type of cancer that can affect the salivary glands.

What Causes Malignant Salivary Gland Tumors?

The cause of salivary gland cancer isn’t clear-cut, but there are a few theories. These include exposure to radiation, viruses like EBV and HIV, a weakened immune system, exposure to sunlight, working in certain industries like rubber or nickel, having certain medical conditions like medulloblastoma or basal cell carcinoma, having certain genes, and expressing androgen receptors.

The idea that radiation exposure could be a major risk factor for salivary gland cancer has been supported by studies involving survivors of the atomic bomb in Japan and patients who had radiation treatment as children for other, non-cancerous conditions. One type of salivary gland cancer, called MEC, seems particularly associated with exposure to radiation.

When it comes to lifestyle habits like tobacco and alcohol use, the link to salivary gland cancer isn’t as clear. Some studies have found that they do increase the risk, while others haven’t. One study found smoking and other types of salivary gland cancer to be correlated, but found no link between smoking and MEC. Long-term inflammation of the salivary glands hasn’t been shown to increase cancer risk, but certain autoimmune conditions like Sjogren syndrome could make someone more likely to develop lymphoma in the salivary glands.

One type of salivary gland cancer, squamous cell carcinoma (SCC), isn’t linked to the usual risk factors like tobacco, alcohol, and UV exposure. Instead, prior radiation to the gland itself looks to be the most significant risk factor for SCC.

Most cases of another form of salivary gland cancer, melanoma, are thought to have spread from skin cancer on the face or scalp. However, there have been cases reported with no other primary sites. While the exact cause is still uncertain, melanocytes, a type of skin cell, have been found in the parotid gland (one of the salivary glands), suggesting they may be the origin for primary melanoma in the salivary glands. Like with lymphoma, people with Sjogren syndrome have an increased risk of developing non-Hodgkin lymphoma in their salivary glands. Studies show that 4.3% of patients with Sjogren syndrome develop this form of lymphoma within 5-10 years.

Risk Factors and Frequency for Malignant Salivary Gland Tumors

Salivary gland cancers are not very common, making up 0.5 to 1.2% of all cancers and 5% of head and neck cancers. They tend to be more frequent in women than men. Out of all salivary gland growths, roughly 21.7% turn out to be cancerous. These cancers mainly occur in specific salivary glands: the parotid gland, submandibular gland, sublingual gland, and minor salivary glands. For example, a salivary gland mass found in a parotid gland has a 15-32% chance of being cancerous, which increases with other glands – nearly 100% of the masses in the sublingual gland are cancerous. In children under 10 years old, these tumors are often more dangerous and harder to treat.

60 to 75% of all salivary gland tumors are located in the parotid gland.
The most common types of cancer in the parotid gland are MEC, AdCC, CExPA, adenocarcinoma, and SCC.
The submandibular gland contains 10-15% of all salivary gland tumors, both benign and malignant.
AdCC is the most common malignant growth in the submandibular gland, followed by MEC and CExPA.
Other less common types include ACC, salivary duct carcinoma, epi-myoepithelial carcinoma, carcinosarcoma, oncocytic carcinoma, and SCC.
In the minor salivary glands, nearly half of all tumors are cancerous, often located in the palate area.

In terms of specific cancer types:

MEC is the most common in both adults and children, with around 89% found in the parotid gland.
AdCC makes up about 10% of all salivary gland cancers and 30% of all minor salivary gland tumors, usually appears in patients aged in their 50s and 60s, and is equally common in both genders. However, it’s slightly more common in women’s submandibular gland.
ACC is commonly found in the parotid gland (over 80% of cases). This type of cancer typically affects women in their 50s.
CExPA comprises 5% to 15% of all salivary gland cancers. If left untreated, up to 25% of pleomorphic adenomas can turn into CExPA. The majority of these occur in the parotid and submandibular glands.
Polymorphous Low-Grade Adenocarcinoma usually occurs in the minor salivary glands. It’s the second most common minor salivary gland cancer.
Salivary Duct Carcinoma makes up 7-10% of salivary gland tumors, often found in older men’s parotid glands. It’s a very aggressive type of cancer.
Squamous Cell Carcinoma (SCC) typically affects men and is found in the parotid. It’s considered rare, but a specific cause for this transformation from normal to cancerous cells is still unknown.
Primary melanoma is extremely rare, constituting only about 0.68% of malignant parotid cancers, typically occurs in men in their 60s and 70s.
Non-Hodgkin’s Lymphoma constitutes less than 10% of malignant salivary gland tumors and is more common in women and those over 50. The most common type associated with Sjogren Syndrome is MALT, accounting for 48% to 75% of all cases, followed by Diffuse Large B-Cell Lymphoma and Follicular Lymphoma. These are typically found in the parotid gland.

Signs and Symptoms of Malignant Salivary Gland Tumors

People with problems in their salivary glands often notice a lump in the area where these glands are situated. Healthcare professionals will take a thorough history, which should take into account any pain, when and how the lump began, how quickly it has grown, and whether there have been any difficulties with swallowing or facial weakness. They will also go over past medical history. Risk factors like previous skin cancer of the head and neck, medical procedures involving the area, family history of cancer, smoking, exposure to radiation, and certain types of job environments will be discussed. The physical examination will focus particularly on the salivary glands, nerves in the head, and glands in the neck.

Cancerous tumors in the salivary glands can be difficult to distinguish from benign (non-cancerous) tumors. They may appear as painless, stationary, or mobile lumps. Advanced cancer may cause pain, fullness in the roof of the mouth or around the throat, lockjaw, skin ulcers, or unusual holes (fistulas). Tumors in the minor salivary glands might cause oral swelling or ulcers, or nasal obstruction and bleeding if they are found in the nasal cavity or back of the nose. If these small tumors develop in the throat or voice box, they could cause difficulty swallowing, painful swallowing, blockage of the airway, voice changes, and shortness of breath during exercise. Rapid growth, pain, facial nerve weakness, and swollen neck glands are worrying signs of possible cancer.

Specific types of salivary gland cancers may have different features and symptoms, for example:

Malignant Epithelial-Myoepithelial Carcinoma (MEC) often appears as a firm, usually painless lump but can sometimes cause facial paralysis. It may also be associated with first-bite syndrome, a condition where there’s severe pain in the parotid gland at the first bite of each meal.
Adenoid Cystic Carcinoma (AdCC) often presents as a slow-growing, solid mass. It typically causes pain because it invades surrounding tissues and nerves. It may also cause neck lymph node metastasis at a rate of 20% during the first presentation. This type of cancer is also associated with first-bite syndrome.
Acinic Cell Carcinoma (ACC) can appear as a slow-growing lump and could cause occasional pain.
Polymorphous Low-Grade Adenocarcinoma (PLGA) usually presents as a well-defined mass with pain. About 8% of cases also have ulceration.
Extracapsular Extension (CExPA) typically presents with a history of a long-standing lump in the parotid gland which suddenly increases in size. This could be associated with pain and nerve weakness in up to 30% of cases.
Salivary duct carcinoma often appears as a firm, unclear mass that invades the surrounding glandular and soft tissues, resulting in associated pain and facial nerve paralysis. More than half of the patients have neck metastasis at the time of first presentation.
Squamous cell carcinoma (SCC) can present as a long-standing mass with sudden, rapid growth, pain, facial nerve paralysis, or skin ulceration.
Melanoma of the parotid gland can appear as a slow-paced, firm mass near the ear with infiltrative growth causing pain, facial nerve paralysis, and skin changes such as ulceration and redness.
Non-Hodgkin’s Lymphoma (NHL) of the salivary gland can present with unilateral or bilateral swelling of the parotid gland, swollen neck glands, enlarged spleen, vasculitis, and red/purple spots that you can feel on your skin.

Testing for Malignant Salivary Gland Tumors

There are various ways that doctors can evaluate potential tumors in your major salivary glands. Each method has its strengths and weaknesses, and can provide different kinds of information. Here they are explained in a bit more detail:

One option is an ultrasound, which is non-invasive and commonly used for examining superficial parotid lesions, which are bumps or lumps near the surface of the parotid glands, the largest of your salivary glands. An ultrasound can help doctors find the exact location of these abnormalities, determine if they are solid or filled with fluid (like a cyst), and even help guide a needle to take a tissue sample. The ultrasound images can reveal if the abnormality displays signs that suggest it could be cancerous or malignant like unevenness, invasive growth, unclear boundaries, or nearby enlarged lymph nodes.

Computed tomography, or CT, is another option. This type of scan uses X-rays to get a detailed image of the tumor – its extent, whether it has infiltrated bones, and if there are affected lymph nodes. It has some limitations, though, as it can be disrupted by dental work and has difficulty clearly showing soft tissue, which can lead to underestimating the size or extent of the abnormality, especially for certain types of tumors like the MEC, AdCC, and ACC.

Magnetic resonance imaging, or MRI, might be recommended for deeper or less accessible areas, such as the deep part of the parotid glands, the sublingual glands under the tongue, and smaller salivary glands scattered throughout your mouth and throat. MRI is particularly useful in detecting any involvement of the nerves, and it can even help surgeons plan by showing them the exact location of facial nerve branches. MRI has an edge over CT in detecting the spread of the tumor along the nerves, particularly for a kind of cancer referred to as AdCC. Certain features on an MRI image, such as inconsistent contrast enhancement, invasive growth into nearby tissues, unclear boundaries, dark areas on T2-weighted imaging, and enlarged lymph nodes, can be signs of cancer. Moreover, a specific type of MRI called diffusion-weighted MRI can provide information about how water molecules move within the tumor, giving an indication of whether the tumor might be cancerous or benign.

Positron emission tomography, or PET, is another imaging technology doctors can use. Its main job is to detect any local or distant spread of the disease. PET scans have been shown to be more accurate than CT scans in showing how far tumor has spread, involvement of lymph nodes, recurrence of the disease, and spread to distant locations due to their ability to pick up on high uptake areas in tissues. However, it can’t tell if a tumor is benign or cancerous, because some non-cancerous tumors can also display high levels of uptake.

While these imaging techniques can provide valuable information, they can’t always definitively tell if a lesion is benign or cancerous. For that, a small sample of the tissue, known as a biopsy, is needed. The approach to obtaining this sample depends upon where the suspected tumor is located. With any biopsy, the goal is to get enough tissue to accurately assess what it is, while minimizing any potential harm. In general, incisional biopsy isn’t recommended for lesions of the parotid gland due to the risk of damaging the facial nerve and the risk of scattering tumor cells. Instead, doctors opt for a fine-needle aspiration biopsy performed under the guidance of an ultrasound. While this technique is straightforward and usually safe, it can sometimes fail in determining the exact type or grade of the tumor. A core needle biopsy that uses a larger needle provides a larger sample that can be helpful in some cases. However, it comes with a bit more discomfort and risk, such as damage to the facial nerve and blood pooling (hematoma). Finally, the intraoperative frozen section technique, used during surgery, has a pretty high success rate at distinguishing between benign and malignant lesions.

Treatment Options for Malignant Salivary Gland Tumors

Surgery to remove the salivary gland along with a border of healthy tissue (known as negative margins) is the primary treatment for all types of salivary gland cancer. Despite attempts to diagnose the condition beforehand with a needle biopsy, a definitive diagnosis might not be made until during the surgery when samples of the salivary gland can be instantly frozen and analyzed in the lab.

The specifics of the surgery, such as whether or not removal of lymph nodes in the neck is needed (a procedure known as neck dissection), depend on the specific type, grade, and stage of the cancer. Additional treatment after surgery, known as adjuvant radiation therapy, may also aid in controlling the disease in the areas it was located. This treatment is usually recommended if the cancer has spread to the neck (cervical metastases), is in an advanced stage, shows aggressive features under the microscope (aggressive histology or grade), invades nerves (perineural invasion), invades blood vessels (lymphovascular invasion), or has grown outside the salivary gland (extra-glandular extension).

Radiation therapy as the primary treatment method is typically reserved for patients who can’t have surgery due to the disease being inoperable, widespread (metastatic disease), or if the patient is not well enough to undergo surgery. In cases of lymphoma (a type of blood cancer), chemotherapy and biologically targeted therapy (which attacks cancer cells in specific ways) are the standard treatments. However, for other types of salivary gland cancer, these treatments play a limited role and are usually used to reduce symptoms and improve quality of life in advanced cases, rather than to cure the disease.

More research and clinical trials are needed to establish chemotherapy and targeted therapies as regular treatment options for salivary gland cancer. They are currently not a standard part of the treatment plan except in certain circumstances.

When doctors are trying to diagnose malignant salivary gland tumors, they also consider these conditions that can cause similar symptoms:

Benign salivary lesions like pleomorphic adenoma, myoepithelioma, basal cell adenoma, Warthin’s tumor, oncocytoma, canalicular adenoma, sebaceous adenoma, lymphadenoma, inverted ductal papilloma, intraductal papilloma, and cystadenoma
Benign salivary cysts
Sialadenitis, inflammation of the salivary gland
Sialoliths, or salivary gland stones
Lymphadenopathy, swelling of the lymph nodes usually due to infection or inflammation
Tuberculosis, a serious infectious disease
Mononucleosis, a viral infection
Chronic Sclerosing Sialadenitis, also known as Küttner tumor, which is more common in the submandibular gland
First Branchial cleft cysts
Lymphoepithelial cysts, especially in patients with weakened immune systems, such as HIV patients
Metastases from tumors of other body sites

It’s crucial for the physician to thoroughly investigate these possibilities through appropriate tests to provide an accurate diagnosis.

Surgical Treatment of Malignant Salivary Gland Tumors

For treating malignant salivary gland tumors (cancerous tumors in the glands that make saliva), the first line of attack is a broad, extensive surgical procedure. The main type of surgery for removing benign (non-cancerous) and malignant (cancerous) tumors in the superficial lobe of the parotid gland (a major saliva producing structure next to your face) is called superficial parotidectomy. This procedure gums down the parotid gland by surgery, carefully avoiding the facial nerves, which are vital for facial expressions and sensations.

If tumors are dug deep into the parotid gland or are quite advanced, doctors resort to a more extensive procedure, a total parotidectomy. If the facial nerve is involved, an even more aggressive approach is used, which involves removing the entire parotid gland and the facial nerve, then reconstructing the facial nerve afterward.

A superficial parotidectomy might lead to loss of some functions of the parotid gland and potential facial nerve paralysis due to the complete facial nerve dissection. Therefore, for smaller, less severe tumors located in the lateral or lower parts of the superficial lobe, a partial superficial parotidectomy could be performed. In this operation, a smaller part of the parotid gland is removed, with facial nerves dissected only around where the tumor is located. Comparatively, individuals who had this procedure experienced better appearance post-surgery, improved sensory and salivary functions, less facial nerve weakness, and as low a risk of cancer recurrence.

If cancerous lesions are found in the submandibular gland (another saliva-producing structure under the jaw), removal of the entire gland should be performed. This operation involves creating space for surgical work by cutting a muscle layer (platysma) near the submandibular gland, isolating and securing critical structures and vessels around the gland, and removing the gland while keeping the tumor’s integrity

In some cases of salivary gland malignancies, cancer can spread to the neck – this is called cervical metastasis. The extent of this spread ranges from 10% to 40%, and its likelihood depends on the characteristics and location of the tumor. In the worst-case scenario, cancer can “hide” in the neck, with disease recognized in 12% to 50% of cases where no symptoms of this were detected. The risk of such “hidden” metastasis (spread of disease) increases with the severity of the tumor, patient’s age, extent of cancer spreading to lymph vessels and other parts of the gland (extra-parotid extension).

There are instances when cancer originating from the parotid gland spreads mostly to one side of the neck. For such cases, experts recommend performing a complete neck dissection on the affected side, which involves removing all lymph nodes and tissues. If the neck shows no signs of disease but the tumor has particular features that suggest a high risk of spread, the same procedure is advised.

For cancers starting in the submandibular gland and minor salivary glands, the detectable spread to the neck stands at 8% to 20% of cases, however, this figure jumps to 41% when a more thorough neck dissection is carried out. For these cases, a selective neck dissection (removing lymph nodes from specific neck areas) is recommended. If the cancer originates from the minor salivary glands in the pharynx or larynx (parts of the throat), neck dissection should focus on the specific levels (II to IV) affected.

What to expect with Malignant Salivary Gland Tumors

Salivary gland malignancies, or cancer in the salivary glands, vary greatly in terms of their outcomes, due to the diverse array of disease types. Generally speaking, younger patients such as children and teenagers tend to have better outcomes than adults. This difference is largely due to lower instances of the cancer spreading to the neck, not invading the local soft tissue, and showing more differentiated disease types. In children, after surgical treatment, the 5-year survival rate is around 85%, compared to 60% for adults.

Regardless of the specific type of disease, a number of factors can worsen the prognosis. This includes being older in age, having a high stage and high grade disease, the cancer spreading to the neck, being male, experiencing pain, facial nerve involvement, invasion of local soft tissue, positive or close margins (which means cancer cells are found at the edge of the removed tissue), distant metastasis (cancer spreading to far away parts of the body), and the presence of other diseases.

The effects of smoking and alcohol on survival rates are debated, with some studies showing no significant influence on overall survival or disease-free survival, while others finding them to be poor indicators for prognosis. Distant metastasis, when the cancer spreads to far away parts of the body, most commonly affects the lungs (40% to 91%), followed by bone (13% to 40%), liver (4% to 19%), soft tissue (9%), distant nodal basins (8%), and the brain (4% to 7%). Distant metastasis is the main cause of death for malignant salivary glands.

Certain molecular markers, such as the overexpression of epidermal growth factor receptor (EGRF) and human epidermal growth factor receptor 2 (HER2), appear to predict a higher risk of the cancer spreading to the neck and worse survival rates. The absence of c-kit expression in certain types of salivary gland cancers is associated with poorer outcomes.

Several subtypes of salivary gland malignancies have different survival rates and behaviors. Some disease subtypes, like MEC and PLGA, have better survival rates than others, like salivary duct carcinoma, which has a 5-year survival rate between 20% and 50%, and most patients die within 3 years of diagnosis. Factors that impact survival rates include gender, age, tumor size, extent of differentiation and invasion, and presence of distant metastasis. Advanced stage and regional metastasis (cancer spreading to nearby lymph nodes) are also poor prognostic factors for some subtypes of the disease. Melanoma and lymphoma also have varying survival rates based on various factors.

Possible Complications When Diagnosed with Malignant Salivary Gland Tumors

After a parotidectomy, temporary facial nerve paralysis could occur in 10% to 65% of patients, while permanent paralysis is less common and occurs in less than 5% of cases. The occurrence of Frey syndrome, where patients can sweat and flush on the side of their face when eating, can range from 2% to 80% after surgery. The frequency can depend on how long it’s been since the operation and how closely the patients are monitored. Treatments for Frey syndrome include antiperspirant cream, injections of botulinum toxin A, and surgery involving different types of tissue flaps.

Other complications of the surgical removal of the parotid gland can include:

Sialocele, which are pockets of saliva that can form under the skin
Salivary fistula, an abnormal opening that allows saliva to leak onto the skin
Neuromas (nerve damage) around the ear
Anesthesia or loss of sensation in front of the ear skin

Patients who have surgery on their submandibular gland (under the jaw) or who get their neck dissected due to cancer spread can have nerve damage. The nerves that could be potentially harmed control shoulder movement, diaphragm (for breathing), tongue movement, throat and voice box function, and facial expression.

Patients might also experience complications from radiation treatment, such as:

Hearing loss
Chronic ear infections
Ear pain
Skin redness
Sores or inflammation in the mouth or throat
Difficulty swallowing
Taste alteration
Dry mouth
Scarring of soft tissues
Death or degeneration of bone tissue due to radiation exposure
New cancers due to radiation exposure

Studies suggest around 36% of patients could develop a hearing loss of 10 dB or higher at 4 kHz. The occurrence of radiation-related death or degeneration of the lower jaw bone (less than 2%), or new cancers (1%), are rare, but can occur approximately 10 to 25 years post radiation treatment.

Recovery from Malignant Salivary Gland Tumors

Post-treatment follow-up appointments aim to keep track of any recurrences of the medical issue and to manage other health problems that may crop up after the treatment. Surgical procedures and radiation therapy can sometimes lead to long-lasting issues with swallowing, such as xerostomia (dry mouth), mucositis (inflammation of the mouth lining), and trismus (lockjaw). Additionally, there may be some cosmetic changes caused by facial nerve paralysis.

Early steps to repair and rehabilitate facial nerves, along with working with speech therapists for swallowing problems, are crucial. These coupled efforts help patients get back to their normal routine prior to treatment as much as possible and improve their quality of life. Most recurrences happen within the first three years of treatment unless the condition is less aggressive or is AdCC (Adenoid cystic carcinoma).

According to the National Comprehensive Cancer Network (NCCN) guidelines, after completing treatment, patients should undergo routine check-ups every 1 to 3 months in the first year; every 2 to 6 months in the second year; every 4 to 8 months in the third to fifth year; and annually after the fifth year. All types of salivary gland cancers call for these follow-up appointments for up to 20 years, especially AdCC, as it is known for its late recurrence or spread.

Patients with high-risk types of cancer or submandibular gland tumors should have chest scans every year since there is a high chance of the cancer spreading to the lungs. As for patients who have undergone neck radiation therapy, their thyroid hormones should be checked every 6 to 12 months.

Preventing Malignant Salivary Gland Tumors

Patients should be made aware of the risk factors that can increase their chances of developing tumors in their salivary glands. They should try to avoid these risk factors as much as possible. Patients and their families should also be informed about the various treatment options available to them and the time it might take for these options to work. These treatment options include surgery to remove the tumor, radiation therapy, and chemotherapy.

Patients and their family members should be guided about the possible risks and complications that could come with each type of treatment. Doctors should properly evaluate the patient’s health conditions for possible complications and decide whether they are suitable for surgery.

It’s important for patients to continue to check in with their doctors regularly after treatment, especially when dealing with salivary gland tumors. Some types of these tumors, such as Adenoid Cystic Carcinoma (AdCC), grow slowly and so, need to be monitored regularly in the long-term to ensure the treatment is effective.

Frequently asked questions

Malignant salivary gland tumors are cancerous growths that can develop in different areas of the salivary glands, including the parotid, submandibular, sublingual, and minor salivary glands.

Malignant salivary gland tumors make up 0.5 to 1.2% of all cancers and 5% of head and neck cancers.

Signs and symptoms of Malignant Salivary Gland Tumors include: - A firm, usually painless lump (Malignant Epithelial-Myoepithelial Carcinoma) - Facial paralysis (Malignant Epithelial-Myoepithelial Carcinoma) - Severe pain in the parotid gland at the first bite of each meal (Malignant Epithelial-Myoepithelial Carcinoma) - Slow-growing, solid mass with pain (Adenoid Cystic Carcinoma) - Neck lymph node metastasis (Adenoid Cystic Carcinoma) - Slow-growing lump with occasional pain (Acinic Cell Carcinoma) - Well-defined mass with pain, and possible ulceration (Polymorphous Low-Grade Adenocarcinoma) - Long-standing lump in the parotid gland suddenly increasing in size, associated with pain and nerve weakness (Extracapsular Extension) - Firm, unclear mass that invades surrounding tissues, resulting in pain and facial nerve paralysis (Salivary duct carcinoma) - Long-standing mass with sudden, rapid growth, pain, facial nerve paralysis, or skin ulceration (Squamous cell carcinoma) - Slow-paced, firm mass near the ear with infiltrative growth causing pain, facial nerve paralysis, and skin changes such as ulceration and redness (Melanoma of the parotid gland) - Unilateral or bilateral swelling of the parotid gland, swollen neck glands, enlarged spleen, vasculitis, and red/purple spots on the skin (Non-Hodgkin's Lymphoma of the salivary gland)

The cause of Malignant Salivary Gland Tumors is not clear-cut, but possible risk factors include exposure to radiation, viruses like EBV and HIV, a weakened immune system, exposure to sunlight, working in certain industries like rubber or nickel, having certain medical conditions like medulloblastoma or basal cell carcinoma, having certain genes, and expressing androgen receptors.

The doctor needs to rule out the following conditions when diagnosing Malignant Salivary Gland Tumors: - Benign salivary lesions like pleomorphic adenoma, myoepithelioma, basal cell adenoma, Warthin's tumor, oncocytoma, canalicular adenoma, sebaceous adenoma, lymphadenoma, inverted ductal papilloma, intraductal papilloma, and cystadenoma - Benign salivary cysts - Sialadenitis, inflammation of the salivary gland - Sialoliths, or salivary gland stones - Lymphadenopathy, swelling of the lymph nodes usually due to infection or inflammation - Tuberculosis, a serious infectious disease - Mononucleosis, a viral infection - Chronic Sclerosing Sialadenitis, also known as Küttner tumor, which is more common in the submandibular gland - First Branchial cleft cysts - Lymphoepithelial cysts, especially in patients with weakened immune systems, such as HIV patients - Metastases from tumors of other body sites

The types of tests that are needed for Malignant Salivary Gland Tumors include: 1. Ultrasound: This non-invasive test can help determine the location of abnormalities, whether they are solid or filled with fluid, and can guide a needle for tissue sampling. It can also reveal signs of cancerous or malignant growth. 2. Computed Tomography (CT) scan: This scan uses X-rays to get a detailed image of the tumor, including its extent, infiltration of bones, and affected lymph nodes. However, it may have limitations in showing soft tissue. 3. Magnetic Resonance Imaging (MRI): This test is recommended for deeper or less accessible areas and can detect nerve involvement. It can also help surgeons plan by showing the location of facial nerve branches. MRI has an advantage over CT in detecting tumor spread along nerves. 4. Positron Emission Tomography (PET) scan: This imaging technology is used to detect the spread of the disease, involvement of lymph nodes, and recurrence. However, it cannot determine if a tumor is benign or cancerous. 5. Biopsy: A small sample of tissue is needed to definitively determine if a lesion is benign or cancerous. Fine-needle aspiration biopsy, core needle biopsy, and intraoperative frozen section technique are some of the biopsy methods used. It is important to note that the specific tests ordered may vary depending on the individual case and the doctor's judgment.

Malignant salivary gland tumors are typically treated with surgery. The main type of surgery for removing these tumors is called superficial parotidectomy, which involves removing the superficial lobe of the parotid gland. In more advanced cases, a total parotidectomy may be necessary. If the facial nerve is involved, an even more aggressive approach is used, which involves removing the entire parotid gland and the facial nerve, then reconstructing the facial nerve afterward. In cases where cancerous lesions are found in the submandibular gland, the entire gland is removed. The extent of treatment may also involve neck dissection, depending on the characteristics and location of the tumor.

The side effects when treating Malignant Salivary Gland Tumors include: - Temporary or permanent facial nerve paralysis (10% to 65% temporary, less than 5% permanent) - Frey syndrome (2% to 80% occurrence), where patients sweat and flush on the side of their face when eating - Sialocele, which are pockets of saliva that can form under the skin - Salivary fistula, an abnormal opening that allows saliva to leak onto the skin - Neuromas (nerve damage) around the ear - Anesthesia or loss of sensation in front of the ear skin - Nerve damage in patients who have surgery on their submandibular gland or who get their neck dissected - Complications from radiation treatment, such as hearing loss, chronic ear infections, ear pain, skin redness, sores or inflammation in the mouth or throat, difficulty swallowing, taste alteration, dry mouth, scarring of soft tissues, death or degeneration of bone tissue due to radiation exposure, and new cancers due to radiation exposure.

The prognosis for malignant salivary gland tumors varies depending on several factors, including age, stage and grade of the disease, presence of distant metastasis, and the specific subtype of the tumor. Generally, younger patients, such as children and teenagers, tend to have better outcomes than adults. The 5-year survival rate after surgical treatment is around 85% for children, compared to 60% for adults. Factors that worsen the prognosis include older age, high stage and grade disease, cancer spreading to the neck, male gender, pain, facial nerve involvement, invasion of local soft tissue, positive or close margins, distant metastasis, and the presence of other diseases.

An oncologist or head and neck surgeon.