Rhabdomyosarcoma is a malignant tumor
developed from the skeletal muscle
tissue. It is a malignant soft tissue
tumor that develops from striated muscle
cells. This is the most common tumor in children and adolescents.
Rhabdomyosarcoma develop mainly
at cephalic cavities (orbit,
nose, sinuses, ears) or urogenital tract (bladder, prostate, vagina, spermatic cord).
More rarely, they can form in muscle in
The annual incidence of rhabdomyosarcoma is about 1 out of 170 000 individuals.
In children less than 15 years,
the annual incidence is estimated to be less than 1/245 000. The median age at diagnosis is 5 years.
As in the case of
most cancers, rhabdomyosarcoma occurs when some cells become abnormal, and then divide uncontrollably to
eventually form a cancerous tumor. The cancer can be different types, depending on the characteristic of the
cells. For instance, the tumor can be embryonal rhabdomyosarcoma because the tumor resembles muscle cells in the
advances in better understanding the mechanisms of cancer development, it is very difficult to accurately
determine the causes of rhabdomyosarcoma. However, scientific studies have not shown that the environment, food,
certain chemicals, family lifestyle of the child can play a role in the development. Psychological and emotional
factors in the parents are also suspected.
However, most rhabdomyosarcomas present no family hereditary factors. In a
family, the disease occurs very often in isolation. There is no
reason to perform tests in the
parents, brothers and sisters of
a child with rhabdomyosarcoma. But it seems in
very exceptional cases, certain genetic defects
may predispose a child to the development of rhabdomyosarcoma. This is the case of children suffering from Recklinghausen's disease, Li-Fraumeni
syndrome or neurofibromatosis type 1
Signs and Symptoms of Rhabdomyosarcoma
Signs and symptoms of rhabdomyosarcoma
can be similar to symptoms of other medical conditions.
In addition, they may vary greatly
depending on the size, location and characteristic localized or
metastatic tumor. It is, therefore, important to consult a health care professional for diagnosis before confirming
In the general,
rhabdomyosarcoma symptoms include the following:
Swelling or mass
Pain or tenderness in the affected area
Limping or other difficulty using the
legs, feet, arms or hands
Diagnostic of Rhabdomyosarcoma
Rhabdomyosarcoma diagnosis is based on the positivity of
muscle markers in immunohistochemistry (IHC), a diagnostic procedure used to detect antigens (for instance proteins) in
cells of a tissue section by exploiting the principle of antibodies binding specifically to antigens in biological
tissues. The detection of the presence
of translocation of the protein allows the health care provider to diagnose the
alveolar forms. The differential
diagnosis includes small round cell tumors such
as lymphomas, neuroblastoma, Ewing's sarcoma, and others. The Immunohistochemical allows studying and distinguishing these tumors.
Treatment begins after the biopsy, usually with a
first phase of chemotherapy tailored
to the child. This phase treatment usually lasts
12 weeks. This includes
chemotherapy drugs: vincristine, ifosfamide, actinomycin D and doxorubicin. Local therapy may
include surgery when possible with more
or less radiation therapy, depending on potential
risks. Alveolar rhabdomyosarcomas have a higher risk and are routinely irradiated. They also receive
more intensive treatment than
Sometimes the local
procedure will be radiotherapy in the head
and neck. Chemotherapy with
the same drugs, follow this local
therapy with a total treatment that lasts 6 months. In some cases, the patient can be
offered a complementary treatment for 6 months to a year with a less aggressive
chemotherapy called maintenance treatment
in order to help keep the cancer from coming back after it has disappeared.
When it comes to rhabdomyosarcomas, survival depends on the location of
the tumor. In localized tumors,
it is greater than 80% for tumors
of the orbit, of the bladder, vagina, and paratesticular region. It is between 60% and 70% for other
localized tumors. Survival rates of patients with metastases at diagnosis is less,
and among them, adolescents and patients with bone
marrow metastases have a survival
of less than 20%.