Rhabdomyosarcoma is a malignant (cancerous), soft tissue tumor found in children. The most common sites are the structures of the head and neck, the urogenital tract, and the arms or legs.

The cause of rhabdomyosarcoma is unknown. It is a rare tumor with only several hundred new cases per year throughout the United States. Some children with certain birth defects are at increased risk, and some families have a gene mutation that elevates risk. However, the vast majority of children with rhabdomyosarcoma do not have any known risk factors.

Symptoms vary depending on location of the tumor. Tumors in the nose or throat may cause bleeding, congestion, swallowing problems, or neurological problems if they extend into the brain.

Tumors in the vagina may be visibly protruding from the opening of the vagina. Bladder and vaginal tumors may cause urinary or bowel obstruction. Tumors in the muscles may appear as a painful lump and are often thought to be an injury. However, they do not go away, but continue to grow, even though they may not continue to be painful.

Diagnosis of rhabdomyosarcoma is often delayed because of lack of symptoms, and because the tumor may appear at the same time as a recent injury. Early diagnosis is important because rhabdomyosarcoma is an aggressive tumor that spreads quickly.

• Biopsy of the tumor
• CT scan of the tumor site
• MRI scan of the tumor site
• CT scan of the chest to look for spread of the tumor
• Bone scan to look for spread of the tumor
• Bone marrow biopsy (may show the cancer has spread)
• Possible spinal tap, to check for spread into the brain, depending on the site of the tumor
• Thorough physical exam