Rhabdomyosarcoma (RMS) is a rare cancer that forms in the body’s soft tissues from cells that would normally become skeletal muscles. While it can occur at any age, RMS is the most common type of soft tissue sarcoma found in children. The tumors can arise almost anywhere in the body, though certain locations are more common than others.
Symptoms and Signs of RMS
The signs of rhabdomyosarcoma depend on the tumor’s location. A common presentation is a lump or swelling that may or may not be painful, and this mass can grow quickly over a period of weeks. For tumors in the head and neck region, symptoms can include headaches, nosebleeds, or visible changes around the eyes, such as bulging or drooping eyelids.
When the cancer develops in the abdomen or pelvis, it can cause pain, vomiting, or constipation. If the tumor is near the urinary tract or reproductive system, it might lead to trouble with urination, blood in the urine, or bleeding from the vagina or rectum. Tumors in the arms or legs present as a noticeable lump or swelling. Many of these symptoms are also associated with more common, less serious conditions.
Causes and Risk Factors
The precise cause for most rhabdomyosarcoma cases is unknown. The cancer arises when rhabdomyoblasts, which are immature muscle cells, begin to grow and divide abnormally, often for no clear reason. There is no evidence that specific environmental factors or lifestyle choices predict its development.
A small percentage of RMS cases are linked to inherited genetic syndromes that increase a person’s risk. These conditions include:
- Li-Fraumeni syndrome
- Neurofibromatosis type 1 (NF1)
- Beckwith-Wiedemann syndrome
- Costello syndrome
- Noonan syndrome
Individuals with these syndromes have a genetic predisposition that makes them more susceptible to this and other tumors.
The Diagnostic Process
Diagnosing rhabdomyosarcoma begins with a physical examination and a review of the patient’s medical history. If RMS is suspected, imaging tests are the next step. Technologies like Computed Tomography (CT) scans and Magnetic Resonance Imaging (MRI) are used to visualize the tumor’s size, shape, and location. A Positron Emission Tomography (PET) scan may also be used to determine if the cancer has spread.
While imaging provides valuable information, a biopsy is the only definitive way to confirm an RMS diagnosis. During this procedure, a small sample of tissue is surgically removed from the tumor and examined by a pathologist. This analysis confirms the presence of cancer and helps classify the specific type of RMS, such as embryonal or alveolar. This diagnostic phase also includes staging the cancer to understand its extent, which helps in planning treatment.
Treatment Approaches
Treatment for rhabdomyosarcoma involves a combination of therapies tailored to the individual, with the goal of eliminating the cancer while minimizing long-term side effects. Surgery is a common component, with the primary objective of removing as much of the tumor as possible.
Chemotherapy is administered either before surgery to shrink the tumor or after. It uses powerful drugs that travel through the bloodstream to kill cancer cells that may have spread beyond the primary tumor site. This systemic treatment helps eradicate microscopic disease.
Radiation therapy is also used, often after surgery, to destroy any remaining cancer cells in the tumor area. It uses high-energy beams to target the specific location where the tumor was, reducing the risk of it returning in that spot. The sequence of these therapies is carefully planned by a team of specialists.
Prognosis and Follow-Up Care
The outlook for an individual with rhabdomyosarcoma depends on a variety of factors. These include the tumor’s location, its size, the specific type of RMS, the stage of the cancer at diagnosis, and how well the tumor responds to the initial treatment. For example, tumors that are localized and can be completely removed surgically often have a more favorable prognosis. The embryonal subtype of RMS has a better outlook than the alveolar type.
After treatment is completed, long-term follow-up care is a standard part of the process. These appointments monitor for any signs of the cancer returning and manage potential long-term side effects from treatments like chemotherapy or radiation. This ongoing surveillance ensures that any new issues are addressed promptly.