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

• ASPS of Salivary Gland
• Salivary Gland Alveolar Soft-Part Sarcoma

What is Alveolar Soft-Part Sarcoma of Salivary Gland? (Definition/Background Information)

• Alveolar soft-part sarcoma (ASPS) is an extremely infrequent, but highly malignant tumor of the soft tissues and muscles. It is formed due to chromosomal aberrations (chromosome 17 and X chromosome) causing abnormal, fused genes. This abnormal gene forms a certain kind of protein that is responsible for the tumor formation
• Alveolar Soft-Part Sarcoma of Salivary Gland is a malignancy that can involve both the major and minor salivary gland. The tumor is usually diagnosed during childhood or young adulthood
• The presenting signs and symptoms of Alveolar Soft-Part Sarcoma of Salivary Gland may include a slowly-growing facial lump and pain while eating/chewing. When the minor salivary glands are involved, the tumor may be present in the mouth
• A combination of surgery, chemotherapy, and radiation therapy may be employed to treat Alveolar Soft-Part Sarcoma of Salivary Gland. However, ASPS tumors are difficult to treat and show poor response to chemotherapy
• Even with prompt diagnosis and adequate treatment, the (long-term) prognosis of Alveolar Soft-Part Sarcoma of Salivary Gland is generally poor. Many tumors are diagnosed after metastasis to the lung or other regions have occurred

Who gets Alveolar Soft-Part Sarcoma of Salivary Gland? (Age and Sex Distribution)

• Alveolar Soft-Part Sarcoma of Salivary Gland is an aggressive malignancy that is seen in children, adolescents, and young adults in the 4-35 years’ age group (average age 14 years)
• Both males and females are affected; a female predominance is noted
• No ethnic or racial preference has been observed

What are the Risk Factors for Alveolar Soft-Part Sarcoma of Salivary Gland? (Predisposing Factors)

• The risk for Alveolar Soft-Part Sarcoma of Salivary Gland is linked to genetic defects on chromosome 17 and X chromosome
• Presently, no other risk factors are evident or identified

The following general risk factors are noted for salivary gland cancers:

• Exposure to ionizing radiation (which may be from natural or artificial sources)
• Occupations involving woodwork, plumbing, and mining (asbestos)
• Working in manufacturing industry related to certain materials, such as rubber products

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s 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 Alveolar Soft-Part Sarcoma of Salivary Gland? (Etiology)

Currently, the cause of Alveolar Soft-Part Sarcoma of Salivary Gland is unclear. The tumor is said to arise from embryonic connective tissues.

• ASPS tumors are thought to occur as a result of gene fusion. The fusion gene occurs when small pieces of two chromosomes break and join to form a new combination gene
• The genes involved in the process include the ASPL gene on chromosome 17 and the TFE3 gene on chromosome X
• Due to the creation of this new gene, certain ‘new’ protein forms that is previously not found in healthy cells. This protein is responsible for the formation of alveolar soft part sarcoma
• However, the exact process of how the tumor forms and develops due to this process is still unclear

Currently, studies indicate defects in the following genes:

• ASPSCR1-TFE3 causing chromosomal abnormality namely der(17)t(X;17)(p11;q25)

The above genetic abnormality can be detected using molecular studies, which may play a significant role in identifying the tumor type, and in some cases, helping the healthcare provider take appropriate treatment decisions.

What are the Signs and Symptoms of Alveolar Soft-Part Sarcoma of Salivary Gland?

Alveolar Soft-Part Sarcoma of Salivary Gland signs and symptoms include:

• Presence of a firm, tender, and visible swelling, typically on the side of the face, that is gradually increasing in size
• Most ASPS tumors do not present any significant symptoms during the initial stages
• The size of the tumors may range from 1-9 cm and they are mostly spherical to ovoid in shape
• Involvement of the parotids is seen in many cases, where the major salivary glands are involved. A firm and painless mass may be observed in the parotid gland
• In the mouth, the tumors have been observed in the inner cheeks, tongue, and larynx. In the head and neck region, the tongue is the most commonly affected location in infants and young children
• 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 Alveolar Soft-Part Sarcoma of Salivary Gland Diagnosed?

A diagnosis of Alveolar Soft-Part Sarcoma of Salivary Gland is made using the following tools:

• Complete evaluation of family (medical) history, along with a thorough physical examination
• Plain X-ray of the head and neck
• 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 body
• MRI scans of head and neck: Magnetic resonance imaging (MRI) uses a magnetic field 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
• Genetic testing and analysis, for detecting any chromosomal aberration

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 is preferred
• Salivary gland core biopsy of the tumor
• Salivary gland open biopsy of the tumor

Tissue biopsy of the tumor:

• A tissue biopsy of the nodule 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

A differential diagnosis may have to be undertaken to eliminate the following tumors prior to establishing a definite diagnosis of ASPS of Salivary Gland:

• Hemangioma; other vascular malformations
• Squamous cell carcinoma
• Paraganglioma
• Perivascular epithelioid cell tumor (PEComa)
• Rhabdomyosarcoma
• Schwannoma

What are the possible Complications of Alveolar Soft-Part Sarcoma of Salivary Gland?

Complications of Alveolar Soft-Part Sarcoma of Salivary Gland may include:

• Cosmetic concerns (facial disfigurement) and severe emotional stress
• Large-sized tumors may compress adjoining tissues and structures resulting in additional complications
• Breathing or swallowing difficulties (if tumor mass obstructs the food pipe or wind pipe)
• Surgically excised tumors are known to return (recurrence rate between 10-25%); often several years may elapse, before the tumors return
• Tumor metastasis to local and distant sites: The lung, brain, spinal cord, and bones are common sites of tumor spread. Involvement of the lung is seen in 40-65% of the cases; involvement of the lymph nodes in 7-10% of the cases
• Usually by the time ASPS tumors are detected; chances are that they would have proliferated and metastasized aggressively
• 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

How is Alveolar Soft-Part Sarcoma of Salivary Gland Treated?

Any combination of chemotherapy, radiation therapy, and invasive surgical procedures are used to treat Alveolar Soft-Part Sarcoma of Salivary Gland. Radiation therapy (in some cases) and chemotherapy (either oral drugs, or intravenous administration) are usually found to be ineffective for head and neck ASPS tumors.

The treatment measures for Salivary Gland ASPS include the following:

• 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
• Embolization is used to provide temporary relief from the symptoms, and reduce blood loss during a surgical procedure
• 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 Alveolar Soft-Part Sarcoma of Salivary Gland be Prevented?

• Current medical research has not established a method of preventing the formation of Alveolar Soft-Part Sarcoma of Salivary Gland
• 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 high metastasizing potential and chances of recurrence, often several years of active follow-up and vigilance is recommended

What is the Prognosis of Alveolar Soft-Part Sarcoma of Salivary Gland? (Outcomes/Resolutions)

• The prognosis of Alveolar Soft-Part Sarcoma of Salivary Gland is generally poor. In many cases, the spread of the tumor to other body sites may have already occurred at the time of diagnosis
• Studies indicate that with metastatic disease, the average survival period is about 3 years; without metastasis, it is about 11 years. The 5-year survival rate is 60%, while after 20 years it is 15%
• Factors that favor better outcomes include age of the individual, small tumor sizes (less than 5 cm), and an absence of metastatic disease at the time of diagnosis
• 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 Alveolar Soft-Part Sarcoma of Salivary Gland:

• The most common location for alveolar soft part sarcoma is the thigh, leg, and buttock. Other not so common locations include the head and neck region (usually in children), female genitalia, and abdominal cavity

Please visit the following link to learn more about alveolar soft part sarcoma:

http://www.dovemed.com/diseases-conditions/alveolar-soft-part-sarcoma-asps/

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/