What are the other Names for this Condition? (Also known as/Synonyms)

• Malignant GCT of Salivary Gland
• Malignant Granular Cell Myoblastoma of Salivary Gland
• Malignant Granular Cell Nerve Sheath Tumor of Salivary Gland

What is Malignant Granular Cell Tumor of Salivary Gland? (Definition/Background Information)

• Granular cell tumor (GCT) is a mostly benign tumor of the soft tissue, which can occur anywhere in the body. Some researchers note that the tumor may be of neural origin (relating to a nerve)
• Malignant Granular Cell Tumor of Salivary Gland is a very rare tumor that is typically observed in the parotid gland. It is usually noticed in young and middle-aged adults with a preference for females
• In a majority of the cases, the tumor is present as a single nodule; though rarely, the tumor can occur as multiple nodules too. Small tumors may be painless and asymptomatic, while larger ones may cause chewing, speaking difficulties
• The diagnosis of Malignant Granular Cell Tumor of Salivary Gland is generally challenging, since it is extremely rare. However, the diagnosis can be confirmed through a tissue biopsy
• The treatment for Malignant Granular Cell Tumor of Salivary Gland involves surgery. Additional therapies including chemotherapy and radiotherapy are employed, based on the assessment of the healthcare provider
• The prognosis of Malignant GCT of Salivary Gland is guarded in most cases. Nevertheless, it also depends on the stage of the tumor, overall health of the individual, and response to treatment

Who gets Malignant Granular Cell Tumor of Salivary Gland? (Age and Sex Distribution)

• Malignant Granular Cell Tumor of Salivary Gland is an extremely rare tumor that can affect individual of any age. Nevertheless, it is usually seen between the ages 30 and 50 years
• It is infrequently observed in children, and very rarely, a congenital appearance is noted
• Both males and females are affected by GCT; though, it is more common in females than males
• In general, granular cell tumors are more common in African Americans than Caucasians

What are the Risk Factors for Malignant Granular Cell Tumor of Salivary Gland? (Predisposing Factors)

• No documented risk factors have been reported for Malignant Granular Cell Tumor of Salivary Gland
• Even though granular cell tumors do not usually run within families, rare cases of increased incidence within families have been reported

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Malignant Granular Cell Tumor of Salivary Gland? (Etiology)

The exact cause of Malignant Granular Cell Tumor of Salivary Gland is unknown.

• Researchers have documented certain genetic changes within the tumor. However, cases where these specific genetic mutations have been observed are rare. Thus, studies regarding genetic changes are limited
• GCT is not associated with any known congenital syndrome
• A benign granular cell tumor may become malignant, even though this is very rare

What are the Signs and Symptoms of Malignant Granular Cell Tumor of Salivary Gland?

The signs and symptoms of Malignant Granular Cell Tumor of Salivary Gland may include:

• Granular cell tumors are usually presents as a single nodule
• Rarely, the tumor can occur as multiple nodules. About 1 in 10 individuals with GCT may have multiple tumors on the body (including in the mouth)
• Small tumors are asymptomatic and present no pain
• Most salivary gland GCTs affect the major salivary glands, predominantly the parotid gland
• Oral cavity GCTs are known to affect the tongue, inner cheeks, hard/soft palate, gums, and floor of the mouth
• Large tumors may present pain and discomfort
• Malignant tumors may cause neurological signs and symptoms, such as facial muscle weakness and pain, due to facial nerve involvement
• Persistent facial pain at the site of swelling of the tumor; this requires an immediate checkup by a healthcare provider

How is Malignant Granular Cell Tumor of Salivary Gland Diagnosed?

A Malignant Salivary Gland Granular Cell Tumor is diagnosed using the following methods:

• Complete physical examination and a thorough medical history
• Plain X-ray of the head and neck region
• Ultrasound scan of the affected salivary gland
• CT or CAT scan with contrast of the head and neck may show a well-defined mass. This radiological procedure creates detailed 3-dimensional images of structures inside the scanned region
• MRI scans of head and neck region: A magnetic field is used to create high-quality pictures of certain parts of the body, such as tissues, muscles, nerves, and bones. These high-quality pictures may reveal the presence of the tumor

Although the above modalities can be used to make an initial diagnosis, a tissue biopsy of the tumor is necessary to make a definitive diagnosis to begin treatment. The tissue for diagnosis can be procured in multiple different ways which include: 

• Fine needle aspiration (FNA) biopsy of the tumor: A FNA biopsy may not be helpful, because one may not be able to visualize the different morphological areas of the tumor. Hence, a FNA biopsy as a diagnostic tool has certain limitations, and an open surgical biopsy may be recommended.  
• Salivary gland core biopsy of the tumor
• Salivary gland open biopsy of the tumor

Tissue biopsy:

• A tissue biopsy of the tumor is performed and sent to a laboratory for a pathological examination. A pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis. Examination of the biopsy under a microscope by a pathologist is considered to be gold standard in arriving at a conclusive diagnosis
• Biopsy specimens are studied initially using Hematoxylin and Eosin staining. The pathologist then decides on additional studies depending on the clinical situation
• Sometimes, the pathologist may perform special studies, which may include immunohistochemical stains, molecular testing, and very rarely, electron microscopic studies to assist in the diagnosis

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Malignant Granular Cell Tumor of Salivary Gland?

The following complications may be noted due to a Malignant Granular Cell Tumor of Salivary Gland:

• Discomfort while speaking, eating, etc.
• Breathing or swallowing difficulties (if tumor mass obstructs the food pipe or wind pipe)
• Surgically excised tumors may recur locally
• Surgical complications: Surgery to remove the tumor mass may result in facial nerve palsy and gustatory sweating (Frey syndrome)
• Post-surgical wound infection
• Side effects from chemotherapy (such as toxicity), radiation therapy
• A malignant GCT can metastasize to other regions of the body. Extensive metastasis is known to result in fatalities

How is Malignant Granular Cell Tumor of Salivary Gland Treated?

The treatment measures for Malignant Granular Cell Tumor of Salivary Gland include:

• Wide surgical excision with removal of the entire lesion is generally performed
• Following surgery, radiation therapy is usually provided for tumors of the head and neck region
• When the tumor is at an inaccessible location, or is unsafe for surgical intervention, non-invasive procedures, such as chemotherapy and radiation therapy (using fast neutron-beam), may be considered
• Recurrent salivary gland tumors are also known to respond better to fast neutron-beam radiation therapy than other treatment modes
• Clinical trial therapies (especially for stage IV disease) including therapeutic drugs, radiation, stem cell transplantation, and monoclonal antibodies, either singly or in combination of various therapies
• Post-operative care is important: A minimum activity level is to be ensured until the surgical wound heals
• Follow-up care with regular screening and check-ups are important, to watch for recurrence and any metastatic behavior

How can Malignant Granular Cell Tumor of Salivary Gland be Prevented?

• The cause of Malignant Granular Cell Tumor of Salivary Gland is unknown; hence, there are no known methods to prevent the tumor occurrence
• Regular medical screening at periodic intervals with blood tests, radiological scans, and physical examinations, are mandatory for those who have been diagnosed with the tumor
• Due to its metastasizing potential and chances of recurrence, often several years of active follow-up and vigilance is recommended

What is the Prognosis of Malignant Granular Cell Tumor of Salivary Gland? (Outcomes/Resolutions)

• The prognosis of Malignant Granular Cell Tumor of Salivary Gland is good, if the tumor is diagnosed early and treated adequately
• Generally, factors that favor better outcomes include small tumor sizes and tumor involvement of the parotid glands (followed by the submandibulars). Tumors affecting minor salivary glands and sublingual (major salivary) glands have generally poorer outcomes
• Unfavorable prognostic indicators include advanced disease stage, certain histological features, high cell division rate, and large tumor sizes
• The prognosis of salivary gland cancer, in general, depends upon a set of several factors that include:
  • Stage of tumor: With lower-stage tumors, when the tumor is confined to site of origin, the prognosis is usually excellent with appropriate therapy. In higher-stage tumors, such as tumors with metastasis, the prognosis is poor
  • The size of the tumor: Individuals with small-sized tumors fare better than those with large-sized tumors
  • Overall health of the individual: Individuals with overall excellent health have better prognosis compared with those with poor health
  • Age of the individual: Older individuals generally have poorer prognosis than younger individuals
  • Individuals with bulky disease have a poorer prognosis
  • Involvement of the lymph node can adversely affect the prognosis
  • Involvement of vital organs may complicate the condition
  • The surgical respectability of the tumor (meaning, if the tumor can be removed completely)
  • Whether the tumor is occurring for the first time, or is a recurrent tumor. Recurring tumors have worse prognosis compared to tumors that do not recur
  • Response to treatment of salivary gland cancer: Tumors that respond to treatment have better prognosis compared to tumors that do not respond to treatment
  • Progression of the condition makes the outcome worse
• An early diagnosis and prompt treatment of the tumor generally yields better outcomes than a late diagnosis and delayed treatment
• In general, for all salivary gland malignancies the following may be noted:
  • The recurrence rate is between 40-65%
  • Spread of the tumor (metastasis) is seen in 38-65% of the cases
  • And, the death rate lies between 35-65%; most deaths occurring within 3 years of tumor diagnosis

Additional and Relevant Useful Information for Malignant Granular Cell Tumor of Salivary Gland:

There are 3 major types of salivary glands and these include the following:

• Parotid glands, found on the sides of the face
• Submandibular glands located at the back of mouth, on both sides of the jaw
• Sublingual glands that are seen under the floor of the mouth

The following article link will help you understand other cancers and benign tumors:

http://www.dovemed.com/diseases-conditions/cancer/