Rhabdomyosarcoma

Origin and Causes

Rhabdomyosarcoma is the most common sarcoma in children. It is diagnosed less frequently in adult patients. It is a sarcoma that originates from smooth muscles. The most common subtypes of rhabdomyosarcoma are alveolar rhabdomyosarcoma, embryonic rhabdomyosarcoma, fusiform cell rhabdomyosarcoma, and pleomorphic rhabdomyosarcoma. Some patients with rhabdomyosarcoma may have a genetic predisposition syndrome such as Li-Fraumeni. However, no risk factor explaining the occurrence of this sarcoma is identifiable in the majority of patients.

 

Symptoms and Signs

Rhabdomyosarcoma can affect any part of the body but is most commonly found in the head and neck, genitourinary tract, and extremities. The first symptoms are often swelling of the area affected by the sarcoma, a progressive mass, and sometimes pain. Some patients may present with lung, lymph node, or bone metastases at diagnosis.

 

Diagnosis

When a sarcoma is suspected, the initial evaluation includes either a CT scan or MRI. The diagnosis is made by biopsy of the suspected area. The biopsy can be performed in the operating room or by the radiology team under local anesthesia. The pathology team will then confirm the diagnosis after analyzing the samples. The investigation may be completed by a chest CT scan and a PET scan.

 

Treatment

The types of treatment for rhabdomyosarcoma vary depending on the site affected, the subtype, and the extent of the disease.

When rhabdomyosarcoma is localized, the treatment of choice is surgery with the goal of removing it as completely as possible. In some situations, surgery may not be possible, and radiotherapy would then be favored. Given that rhabdomyosarcoma is an aggressive cancer that can cause metastases, chemotherapy before surgery or radiotherapy and after surgery and radiotherapy is necessary. The most commonly used chemotherapy protocols are VAC (Vincristine-Actinomycin-Cyclophosphamide).

In the case of recurrent rhabdomyosarcoma, chemotherapy is offered with the aim of controlling symptoms and disease progression. The agents of choice are: doxorubicin, Temozolomide-Irinotecan, Ifosfamide-Etoposide. Clinical trials may also be explored.

 

Follow-up

After surgery, patients with rhabdomyosarcoma will be closely followed due to the risk of recurrence. Follow-up will be every 3 months for the first two years and then every 6 months until 5 years. Afterwards, visits will be spaced out to years until 10 years.