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

• PMS (Psammomatous Melanotic Schwannoma)
• PMS in Carney Complex
• Psammomatous Melanotic Schwannoma in Carney Complex

What is Psammomatous Melanotic Schwannoma? (Definition/Background Information)

• Psammomatous Melanotic Schwannoma (PMS) is a rare tumor of the soft tissue, occurring usually beneath the skin (subcutaneously). It is mostly seen to occur in individuals with Carney complex, an autosomal dominant genetic condition

Note: Psammomatous Melanotic Schwannoma should not be confused with conventional or cellular schwannoma; they are completely different tumor types.

• Carney complex comprises a combination of medical conditions that includes multiple tumors, such as myxomas, schwannomas, endocrine disorders, and pigmented skin conditions
• Psammomatous Melanotic Schwannomas are typically observed in young and middle-aged adults, in the spinal nerves, nerves of the gastrointestinal tract, and soft tissues of the limbs
• The signs and symptoms of Psammomatous Melanotic Schwannomas are linked to the tumor site. Also, a majority of these tumors are benign, though 1 in 10 may be malignant. The malignant tumors may metastasize to various body organs
• Thus, the treatment of Psammomatous Melanotic Schwannoma may involve a surgical removal of the tumor, with chemotherapy and radiotherapy, in case of malignant behavior
• The prognosis is excellent for tumors that are benign and not associated with Carney complex. The prognosis of Psammomatous Melanotic Schwannoma is variable, if they are malignant or are associated with Carney complex, or both

Who gets Psammomatous Melanotic Schwannoma? (Age and Sex Distribution)

• Psammomatous Melanotic Schwannoma is a rare kind of tumor, typically observed between the age ranges of 20-40 years (young and middle-aged adults)
• It is observed in both males and females
• PMS has no known geographical, racial, or ethnic preference; they are seen worldwide
• Approximately 50% of the tumors occur in association with Carney complex, which is a congenital condition

What are the Risk Factors for Psammomatous Melanotic Schwannoma? (Predisposing Factors)

The risk factors for Psammomatous Melanotic Schwannoma include:

• The presence of Carney complex
• A family history of the tumor

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 Psammomatous Melanotic Schwannoma? (Etiology)

• The exact cause and mechanism of Psammomatous Melanotic Schwannoma formation is unknown
• Nevertheless, Carney complex is caused by defective genes and is inherited in an autosomal dominant manner

What are the Signs and Symptoms of Psammomatous Melanotic Schwannoma?

In some cases, Psammomatous Melanotic Schwannoma may not present any signs and symptoms. In tumors with signs and symptoms, it may be dependent upon the location of the tumor and its association with Carney complex. These may include:

• The tumors occur as a firm mass and are mostly solitary, though sometimes multiple tumors are observed
• The tumor size may range from 1-10 cm; the typical size of the tumor at diagnosis is around 5 cm
• Common locations of the tumors include the spinal nerves, nerves of the GI tract, soft tissues of the arms, legs, and trunk
• They can also occur in other body parts such as the bone (Psammomatous Melanotic Schwannoma of Bone), liver (Psammomatous Melanotic Schwannoma of Liver), heart (Psammomatous Melanotic Schwannoma of Heart), and bronchus (Psammomatous Melanotic Schwannoma of Bronchus)

Signs and symptoms of underlying Carney complex are observed in individuals with the disorder.

How is Psammomatous Melanotic Schwannoma Diagnosed?

A diagnosis of Psammomatous Melanotic Schwannoma is made using the following tools:

• Complete physical examination with thorough evaluation of the individual’s medical history (including history of Carney complex)
• Neurological exam of the entire body
• Radiological studies (CT, MRI scan) of the affected region
• Nerve conduction studies of the affected nerve
• Other specific tests may be conducted based on the location of the tumor
• Tissue biopsy: A tissue biopsy is performed and sent to a laboratory for a pathological examination, who 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
• A differential diagnosis may be performed to eliminate malignant melanoma

Note: In individuals diagnosed with Psammomatous Melanotic Schwannoma, the healthcare provider must look for other signs and symptoms of Carney complex.

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 Psammomatous Melanotic Schwannoma?

The complications can depend on where the tumors are located. The complications from Psammomatous Melanotic Schwannoma could include:

• Compression of the underlying nerve, which can affect nerve function
• Damage to the nerve or organ during surgery to remove the tumor
• Infrequently, recurrence of the tumor after surgery, if the tumor is incompletely removed
• Up to 10% of Psammomatous Melanotic Schwannomas can become cancerous (malignant transformation of the tumor). A malignant PMS can metastasize to various body parts such as the lung, liver, or spleen
• Complications of Carney complex that might include heart failure and brain stroke

How is Psammomatous Melanotic Schwannoma Treated?

Treatment measures for Psammomatous Melanotic Schwannoma may include the following:

• In many cases of benign tumors not related to Carney complex, if no symptoms are observed, then no treatment may be necessary. Periodic observations can be maintained through regular check-ups
• Treatment of the underlying Carney complex
• Complete surgical excision and removal of the tumor is the preferred treatment option for benign tumors
• Malignant tumors can be treated with a combination of surgery, chemotherapy, and radiation therapy, depending on the location of tumor
• Post-operative care is important: One must maintain minimum activity levels, until the surgical wound heals
• Follow-up care with regular screening and check-ups are important and encouraged

How can Psammomatous Melanotic Schwannoma be Prevented?

Current medical research has not established a way of preventing Psammomatous Melanotic Schwannoma. However, for those tumors that occur with Carney complex, the following measures may be considered:

• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• If an individual is diagnosed with Carney Complex, then it is important to screen close blood relatives of the patient too

Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders.

What is the Prognosis of Psammomatous Melanotic Schwannoma? (Outcomes/Resolutions)

• The prognosis of Psammomatous Melanotic Schwannoma is excellent, if the tumors are benign and do not arise in association with Carney complex. In such cases, a surgical removal of the tumor is curative
• 90% of the tumors are benign and 10% are seen to be malignant. The prognosis of malignant tumors depend on their stage including whether they have metastasized to other body regions or organs
• The prognosis of PMS when it is associated with Carney complex, depend upon the underlying disorder. The outcome of Carney Complex depends upon the location and type of tumors and the combination of signs and symptoms

Additional and Relevant Useful Information for Psammomatous Melanotic Schwannoma:

From a biopsy specimen, it is very hard to differentiate between a benign or malignant Psammomatous Melanotic Schwannoma, and hence, work-up of the patient for metastasis is very important.