Rhabdomyosarcoma is a malignant tumor that arises from mesenchymal embryonic cells that normally differentiate into skeletal muscle cells. That is why a neoplasm can develop in any part of the body where there is muscle tissue, and its symptoms are very diverse. The tumor is usually found using CT or MRI, and the diagnosis is confirmed using a biopsy. Treatment is complex: rhabdomyosarcoma surgical removal in combination with chemotherapy and radiation.
Rhabdomyosarcoma is considered the third most common solid tumor located outside the central nervous system in children (1st place – Wilms tumor, 2nd – neuroblastoma). Tumor belongs to the group of soft tissue sarcomas, often affecting children under 7 years of age.
Rhabdomyosarcoma is a serious disease with a serious prognosis, but with timely seeking medical help and modern complex therapy, it is completely curable. It is very important to find a competent and qualified specialist who will help to establish the correct diagnosis and select an effective treatment regimen. These are the doctors who work in Pediatric Oncology Department of Tel Aviv Medical Clinic. Each individual case of rhabdomyosarcoma in a child is managed jointly by an entire multidisciplinary team of specialists. Developing an examination plan and treatment regimen, doctors take into account all patient’s characteristics and his disease. Thanks to this personalized approach, it is possible to obtain the best results for each child, which has a positive impact on long-term prognosis.
Causes and types of rhabdomyosarcoma
Unfortunately, the exact causes of rhabdomyosarcoma are currently unknown, but there are risk factors that increase the baseline risk of this disease among children. These include:
- Age. The younger the child, the higher the risk of rhabdomyosarcoma developing. Approximately 75% of cases are diagnosed before the age of 10 years. Adults also get this disease, but much less frequently.
- Male gender. The tumors develops in boys more often than girls.
- Caucasian children have a higher risk of rhabdomyosarcoma developing compared to negroid race children.
- Some inherited syndromes and diseases increase the risk of rhabdomyosarcoma developing. Thus, a connection has been noted between the onset of this tumor and Li-Fraumeni syndrome, mutations in DICER1 gene, neurofibromatosis type 1, Costello syndrome, Beckwith-Wiedemann syndrome and Noonan syndrome.
Depending on the histological features of tumor tissue structure, there are 2 types of rhabdomyosarcoma:
- Fetal – most often diagnosed in children under 5 years of age, favorite localization is head, neck, bladder, vagina in girls, prostate gland and testicles in boys.
- Alveolar – this tumor occurs with equal frequency in all age groups and mainly affects the muscles of arms, legs and torso.
Symptoms of rhabdomyosarcoma
Rhabdomyosarcoma can occur almost anywhere in the body, but the tumor is primarily located in several areas:
- head and neck (about 35% of cases), usually inside the eye fossa or in nasopharynx cavity, this is the most common location among school-age children;
- genitourinary system (about 25% of cases), usually the tumor is located in bladder, prostate gland or vagina, often occurs in infants and children of primary preschool age;
- extremities (about 20% of cases), this is the most common form of rhabdomyosarcoma among teenagers;
- mixed localization (about 20% of cases).
If metastases develop, they are most often found in lungs; bones, bone marrow and lymph nodes are also affected. Metastases develop in 20-25% of patients at the time of diagnosis.
Children with rhabdomyosarcoma usually do not have common symptoms such as fever, night sweats, or progressive weight loss. Most often, a palpable tumor is discovered in a child during a routine examination by a pediatrician, or parents themselves notice a tumor that becomes noticeable to naked eye. In some situations, the first manifestation may be certain organs dysfunction due to influence on them a tumor conglomerate.
Tumors of orbit and nasopharynx can cause watery eyes, eye pain or protrusion of eyeballs from their sockets (exophthalmos), persistent nasal congestion, a change in voice, or abnormal nasopharyngeal discharge.
Tumors of genitourinary system can cause abdominal pain, palpable abdominal masses, difficulty urinating, and blood in urine.
Rhabdomyosarcoma localized in extremities appears as a homogeneous, non-painful protrusion on arms or legs.
Not all children, especially those of younger preschool age, can correctly voice their complaints and assess their well-being, so a lot depends on vigilance of their parents. And the sooner they attend a doctor, the higher chances of a favorable treatment outcome.
Important! If there are any changes in baby’s health, do not hesitate! Seek professional help, and qualified specialists from TAMC Pediatric Oncology Department will help you quickly and efficiently understand any situation.
Modern diagnostic methods
Pediatric Oncology Department at TAMC has an excellent material and technical base for carrying out fast and accurate comprehensive diagnostics, which takes from 3 to 5 working days.
At the first consultation with department’s leading oncologist, special attention is paid to studying the medical history, a thorough medical examination, obtaining information about symptoms, general health, previous diseases and risk factors for rhabdomyosarcoma in child.
At the second stage (direct diagnosis), the patient is subjected to the full range of necessary laboratory tests and instrumental diagnostic techniques. Using modern medical imaging methods (ultrasound, CT, MRI), tumor localization, its size, shape, location close to important anatomical structures and organs is determined. Also, MSCT, MRI, PET-CT, PET-MRI, bone scintigraphy are used to determine the presence of metastatic lesions in order to set the stage of the disease, according to which a set of therapeutic measures is planned.
A biopsy and subsequent histological examination of obtained material are necessarily carried out to confirm the diagnosis and determine the histological, as well as molecular genetic features of tumor. After biopsy, we send all materials for revision to the best pathohistological laboratories in Israel, where they are reviewed by a sarcoma specialist. Thanks to such thorough checks, we are absolutely confident in diagnosis correctness and effectiveness of further chosen treatment tactics.
Prognosis for rhabdomyosarcoma
The prognosis for a child with rhabdomyosarcoma depends on a number of factors:
- tumor localization;
- the possibility of tumor conglomerate radical surgical removal;
- the presence of metastatic screenings;
- child’s age at the time of diagnosis;
- histological variant of tumor.
Based on these and other factors, all patients are grouped into low, medium, and high risk categories. The scope of treatment measures depends on this risk group. Overall survival varies from 90% in low-risk patients to 50% in high-risk patients.
Rhabdomyosarcoma modern treatment
For rhabdomyosarcoma, a combination treatment approach is used, which includes chemotherapy, surgical removal and/or radiation, and sometimes experimental therapies and innovative drugs.
Systemic chemotherapy is mandatory for all children with rhabdomyosarcoma. Chemotherapy can be used before surgery to reduce tumor primary size and make it more operable. After surgery, chemotherapy is given to destroy any remaining cancer cells and prevent recurrence of the disease.
Standard chemotherapy regimens include vincristine, actinomycin D, cyclophosphamide, ifosfamide, and irinotecan. Currently, the following chemotherapy protocols are actively used: IVA, VAC and Irinotecan-Vincristine.
Many children are offered treatment for rhabdomyosarcoma as part of clinical trials. For some of them, this is the only real chance for a full recovery and a future healthy life.
Targeted therapy drugs are innovative drugs that have a targeted effect on malignant cells. Kinase inhibitors and monoclonal antibodies (mTOR, IGF1R and VEGF inhibitors) are used to treat rhabdomyosarcoma.
Surgical excision of tumor conglomerate is performed within healthy tissue to reduce the risk of relapse in future. If possible, the tumor is completely removed. If its size, location or close proximity to vital organs does not allow radical surgery, our surgeons perform partial resection.
In Pediatric Oncology Department of TAMC, minimally invasive surgical techniques are used whenever possible, and they also effectively practice robotic innovative surgery, which makes it possible to reduce the extent of injured tissue, avoid the risk of postoperative complications and shorten recovery period after surgery.
More recently, surgeons acted radically – amputating a limb for rhabdomyosarcoma. Today, thanks to new technologies introduction, amputation is performed in very rare cases. When performing tumor resection, surgeons at our medical center try to remove the changed tissue as much as possible, while preserving the healthy part of limb. When removing a large amount of tissue, the next stage of surgical intervention is necessarily reconstructive surgery – reconstruction using artificial implants or autografts. Limb parts 3D printing technology that are removed due to tumor lesions is also available to our patients.
Cryosurgical ablation is a minimally invasive medical procedure that can be used alone or combined with other treatments such as classical surgery, chemotherapy and radiation therapy to treat complex cases. When combined with surgical excision, cryosurgery minimizes the risk of cancer cells spreading during resection.
After organ preserving surgery, in future the child will be able to lead an active lifestyle, play sports, avoiding contact injuries. If during surgical treatment the damaged area was replaced with an implant, then subsequent surgical interventions for replacement or correction may be required as the child grows. Such corrective interventions do not require long-term hospital treatment and are sometimes performed in a day hospital.
Radiation is often used in complex treatment of children with rhabdomyosarcoma. Radiation therapy is prescribed before and/or after surgery. In most cases, radiation therapy gives good results, since the cells of this tumor are sensitive to ionizing radiation.
In each case, treatment program is combined individually, depending on characteristics of clinical case and patient himself.
