Plasmacytoma

Plasmacytomas are a cancerous condition classified as abnormal plasma cells that grows within soft tissue or within bones. It may present as a solitary mass or in multiple areas of the body, and can develop into multiple myeloma if left untreated. 

Blood is the bodily fluid of the circulatory system that provides nutrients and oxygen to our tissues, and helps remove waste from our bodies. There are three primary types of blood cells produced in the inner, spongy portion of the bone (bone marrow) from stem cells (immature blood cells that develop into either red blood cells (RBCs), white blood cells (WBCs) or platelets). RBCs, or erythrocytes, are responsible for providing oxygen to the tissues in our body, as well as transporting carbon dioxide to the lungs to be exhaled. WBCs are responsible for fighting infection and disease in the body. Plasma cells are a type of B lymphocyte (a type of mature WBC) that produces a type of protein known as antibodies or Ig in response to foreign bacteria, viruses, or other harmful substances in the body. Platelets are blood cells that play a major role in blood clotting (or coagulation), which is an important process that helps reduce blood loss after an injury. 

Plasmacytomas are more common in males, and tend to be diagnosed around the age of 55. However, anyone can develop this disease. 

Types of Plasmacytomas 

There are two primary types of plasmacytomas that are categorised by tumour location. 

Solitary Bone Plasmacytoma 

Solitary bone plasmacytomas are the most common subtype of this disease, and are found in the bones of the body. It is most commonly found in the spine (often the thoracic spine), however they may also develop in the pelvis, rib, sternum (breast bone), clavicle, limb bones, skull and/or scapula. In many cases, solitary bone plasmacytomas may progress to multiple myelomas, and may not have as good of a prognosis as other types of plasmacytomas. 

Solitary Extramedullary Plasmacytoma 

Solitary extramedullary plasmacytomas are a less common subtype of this disease, and are found outside of the bone in soft tissue.  It is most commonly found in the head and neck region (mainly the nose, throat and sinuses), however it can also develop in the gastrointestinal tract, lymph nodes, bladder, skin, limbs and/or lungs. Solitary extramedullary plasmacytomas don’t often progress to multiple myeloma, and generally has a better prognosis than solitary bone plasmacytomas. 

Treatment 

When cancers are detected, they are staged and graded based on size, metastasis, and how the cancer cells look under the microscope. Staging and grading helps your doctors determine the best treatment for you. However, because of how rare plasmacytomas are, there is currently no standard staging and grading system for this disease. Instead of staging and grading, your doctor will recommend a treatment plan based on the following factors:  

  • The type of plasmacytoma you have. 
  • Whether or not the cancer has metastasised. 
  • Your age. 
  • General health. 
  • Your treatment preferences. 

Your doctor may also recommend genetic testing, which analyses your tumour DNA and can help determine which treatment has the greatest chance of success. They will then discuss the most appropriate treatment option for you.    

Treatment is dependent on several factors, including location, stage of disease and overall health.  

Treatment options for plasmacytomas may include: 

  • Radiation therapy. 
  • Chemotherapy. 
  • Surgery (rare – may be required in situations where solitary bone plasmacytoma causes skeletal instability or high fracture risk). 
  • Clinical trials. 
  • Palliative care. 

Risk factors 

Because of how rare plasmacytomas are, there has been limited research done into the risk factors of this disease. 

Symptoms 

The symptoms of plasmacytomas often vary by subtype. 

Symptoms of Solitary Bone Plasmacytomas 

The symptoms of solitary bone plasmacytomas often vary by location. In general, the symptoms of this subtype may include: 

  • Pain at the site of the tumour. 
  • Compression fractures of thoracic and/or lumbar regions of the spine, which can cause: 
    • Muscle spasms. 
    • Back pain. 
  • Nerve root compression, which may cause: 
    • Sharp back pain, arms, legs and/or shoulders. 
    • Weakness or loss of reflexes in the arms and/or legs. 
    • Numbness or tingling in the arms and/or legs. 
  • Spinal cord compression, which may cause: 
    • Pain and/or stiffness in the neck and/or back. 
    • Burning pain in the arms, buttocks and/or legs. 
    • Numbness, cramping or weakness in the arms, hands or legs. 
    • Difficulties with coordination. 
    • Urinary incontinence (severe cases). 
    • Severe or increasing numbness, pain or weakness in the legs (severe cases). 
  • Sharp chest pain that worsens during breathing. 

Symptoms of Solitary Extramedullary Plasmacytomas 

The symptoms of solitary extramedullary plasmacytomas often vary by location. In general, the symptoms of this subtype may include: 

  • Headache. 
  • Nasal discharge. 
  • Nose bleeds. 
  • Nasal obstruction. 
  • Sore throat. 
  • Voice hoarseness. 
  • Changes in the voice. 
  • Difficulties swallowing. 
  • Dyspnea.
  • Upper abdominal pain. 
  • Coughing up blood. 
  • Unexplainable loss of appetite/weight loss. 
  • Abdominal discomfort/obstructions. 
  • Pulmonary nodules. 

Not everyone with the symptoms above will have cancer, but see your general practitioner (GP) if you are concerned.  

Diagnosis

If your doctor suspects you have a plasmacytoma, they may order the following tests to confirm the diagnosis and refer you to a specialist for treatment:

  • Physical examination.
  • Imaging tests, potentially including:
    • MRI (magnetic resonance imaging).
    • CT (computed tomography) scan.
    • PET (positron emission tomography) scan.
    • X-ray.
  • Blood tests.
  • Urine tests.
  • Bone marrow aspiration.
  • Biopsy.

References

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