Testing & Diagnosis for Leiomyosarcoma in Children

The first step in treating your child is forming an accurate and complete diagnosis. To diagnose your child's leiomyosarcoma, your specialist at Boston Children's Hospital uses a combination of medical history, physical examination and laboratory tests.

How does a doctor know that it’s leiomyosarcoma?

Diagnostic procedures for leiomyosarcoma determine the exact type of tumor your child has and whether the tumor has spread. These may include a:

  • physical exam, including neurologic function tests including: reflexes, muscle strength, eye and mouth movement, coordination and alertness
  • x-rays, which produce images of internal tissues, bones and organs onto film
  • magnetic resonance imaging (MRI), which produces detailed images of organs and structures within the body and/or spine
  • computerized tomography scan (also called a CT or CAT scan) to capture a detailed view of the body, in some cases
  • biopsy or tissue sample from the tumor to provide definitive information about the type of tumor; other is collected during surgery
  • bone scan to detect bone diseases and tumors as well as to determine the cause of bone pain or inflammation
  • complete blood count (CBC), which measures size, number and maturity of different blood cells in a specific volume of blood
  • blood tests including blood chemistries
  • CT guided core needle biopsy
    • less invasive than an incisional biopsy

What is differentiation (hertological grading)?

Differentiation is how much a cell stands out from surrounding cells.

For example, a fat cell looks completely different than a cartilage cell.

In terms of leiomyosarcoma, differentiation is about how different the tumor cells appear from the normal cells it originated from.

For example, if it is a leiomyosarcoma of soft tissue, it’s a matter of how different the tumor may look from the soft tissue.

Highly differentiated tumors look like the cells they originated from.

Low differentiated tumors look very different from the cells they originated from.

The less differentiated the tumor is, the more mitosis is going on, meaning the tumor cells are dividing and growing.

What is grading of tumors?

  • Grading is a way to identify the severity of the tumor, and helps to identify the appropriate treatment.
  • There are three grades: low, intermediate and high.
    • Low grade means it is more differentiated, local and usually harmless (benign).
    • High grade means it is undifferentiated, growing and usually cancerous.
  • Ideally, you want a low grade tumor which is highly differentiated, with little or no growth and is benign.

After we complete all necessary tests, our experts meet to review and discuss what they have learned about your child’s condition. Then we meet with you and your family to discuss the results and outline the best treatment options.