Lymphoma (continued)

Although no lifestyle factors have been definitely linked to childhood lymphomas, kids who have received either radiation treatments or chemotherapy for other types of cancer seem to have a higher risk of developing lymphoma later in life.

In most cases, neither parents nor kids have control over the factors that cause lymphomas. Most lymphomas come from noninherited mutations (errors) in the genes of growing blood cells. Regular pediatric checkups can sometimes spot early symptoms of lymphoma in the relatively rare cases where this cancer is linked to an inherited immune problem, HIV infection, prior cancer treatment, or treatment of immunosuppressive drugs for organ transplants.

Diagnosis

The doctor will check your child's weight and perform a physical examination to look for enlarged lymph nodes and signs of local infection. He or she will also examine your child's chest using a stethoscope and will feel the abdomen to check for pain, organ enlargement, or fluid accumulation.

In addition to doing a physical exam, the doctor will take a medical history by asking you about your child's past health, your family's health, and other issues.

Sometimes, when a child is found to have an enlarged lymph node for no apparent reason, the doctor will watch the node closely to see if it continues to grow. The doctor may prescribe antibiotics if the gland is believed to be infected by bacteria. If the lymph node remains enlarged, the next step is a biopsy (the removal and examination of tissue, cells, or fluids from the body). Biopsies are also necessary for lymphomas that involve the bone marrow or structures within the chest or abdomen.

Depending on the location of the tissue to be sampled, the biopsy may be done using a thin hollow needle (known as needle aspiration) or a small surgical incision made under local anesthesia (the skin around the biopsy site will be numbed with medication). Sometimes, a biopsy may require a larger surgical incision under general anesthesia. This is the case in an excisional biopsy, where the entire enlarged lymph node or a chain of lymph nodes is removed.

In the laboratory, tissue samples obtained from the biopsy are examined to determine the specific type of lymphoma. In addition to these basic lab tests, more sophisticated tests are also generally done, including genetic studies, to distinguish between specific types of lymphoma.

To identify which areas of the body are affected by lymphoma, the following tests are also commonly used:

• blood tests, including complete blood count (CBC)
• blood chemistry, including tests of liver and kidney function
• bone marrow biopsy or aspiration
• lumbar puncture (spinal tap) to check for cancer spread to the central nervous system (brain and spinal cord)
• ultrasound
• computed tomography (CT) of the chest and abdomen or sometimes X-rays
• magnetic resonance imaging (MRI)
• bone scan or gallium scan (when a radioactive material is injected into the bloodstream to look for evidence of inflammation or bone tumors)
• gallium scan to look for tumor or inflammatory cells
• Positron emisson tomography (PET) scan to look for abnormal cells

These tests are important for determining the spread of the lymphoma within the body and in deciding which type of treatment should be used.