Solid Tumors in Children

What is a solid tumor?

Solid tumors appear as lumps that can be felt or seen by radiologic studies. Solid tumors can occur in several places, including bones, soft tissue (muscles and tendon), and different body organs like the kidneys, liver, eyes, etc. Some types of solid tumors occur only in children, including neuroblastoma and Wilms tumor. Other types can occur in children or adults, but the treatments that are effective for children may differ from those for adults.

Solid tumors make up approximately 30% of all cancers in children. The term does not include solid tumors that may grow in the brain.

Most common types of solid tumors

Neuroblastoma: This is a cancer that is usually found in the abdomen. It mostly occurs in infants and young children.
Rhabdomyosarcoma: This is a cancer that originates in the muscles. It can occur almost anywhere in the body.
Retinoblastoma: This is the most common form of eye cancer. This cancer is usually diagnosed before a child reaches the age of 3 years.
Wilms tumor: This cancer occurs in one or both kidneys. This type of cancer is found in children about 3 to 4 years old.
Osteosarcoma and Ewing sarcoma: Both of these cancers are bone cancers. Ewing sarcoma most commonly occurs in middle of the long leg bones, the hip, chest wall, or the spine in young teens, while osteosarcoma (the most common bone tumor) most often happens in the wide end of a leg or arm bone of a teenager.
Hepatoblastoma: This cancer is a common liver tumor in infants; it usually presents with a large mass in the right side of the abdomen.

What are the symptoms of Solid tumors?

Symptoms of solid tumors can vary depending on the type, size and location of the tumor and whether it has spread. The most common presenting symptom is swelling or a mass that can be palpated. Other vague and less specific symptoms include pain, bloody urine, double vision or other eye problems, constipation, and fever. These symptoms can occur for other reasons, but if they do not go away then you should to contact your doctor.

How are Solid tumors diagnosed?

The primary work-up includes a thorough examination followed by select evaluations depending on the type of tumor. Baseline blood tests of hematologic, liver and kidney function are usually obtained.

Further work-up depends on the findings and symptoms, but usually consists of one or more of the following: MRI/CT of the primary tumor, CT thorax, bone scan, urine analysis for specific tumor products in some types of cancer (catecholamine like MVA, HVA), and tumor markers in blood - if indicated (NSE, AFP, HCG).

In most cases, diagnosis of a solid tumor requires a biopsy though there are some exceptions. In retinoblastoma, for example, a diagnosis is made by an eye exam; and in some other types of solid tumors diagnosis can be made based on history, examination, images and blood tests without the need to confirm with tissue.

Tissue diagnoses or biopsies are surgical procedures that are usually done while the patient is asleep so that they do not experience any pain. This can be done with different techniques, though imaging-guided biopsy is usually used (CT or US guided). In rare cases, open biopsy might be needed. The tissue from the biopsy is looked at under a microscope by a pathologist - a specialist at identifying problems with cells like cancer - who makes the diagnosis. It is often necessary to wait 2-7 days after getting the biopsy for the result before starting treatment.

How are solid tumors treated?

There are many types of cancer treatment. The type(s) of treatment that a child with cancer receives depends on the type of cancer and how advanced it is. Common treatments include: surgery, chemotherapy (drugs used to cancer cells or keep them from growing), radiation therapy (X-rays that kill cancer cells or keep them from growing), immunotherapy, and stem cell transplant.

The approach for solid tumors is multidisciplinary, which means that the team includes a pediatric oncologist, pediatric surgeons, an orthopedic oncologist, a pediatric radiation oncologist, pediatric pathologists, pediatric radiologists and pediatric oncology nurses. This is to ensure an in-depth discussion of each case and personalized treatment plans for every patient.

Treatment is based on the specific type and stage of solid tumor. In some cases, treatment may be surgery alone; in other cases your doctor may use some or all of the other modalities of treatment.

What is the outcome and prognosis of solid tumors?

Cure rates vary based on the type of tumor, its location and spread in the body. Other factors like age of the child, the biological characteristics of the tumor and the subtype of the tumor may play an important role in determining the outcome. Solid tumors that are removed completely by surgical intervention usually carry a good prognosis.