Rhabdomyosarcoma refers to one of the varieties of sarcoma - cancer of the soft tissues, bones or connective tissue. The tumor most often appears in the muscles attached to the bones. Rhabdomyosarcomas are malignant neoplasms that originate in the skeletal muscle. They start in any one part of the body or in several places at once.
Microscopically, rhabdomyosarcoma in adults looks like oblong or round cells with a bizarre shape. This tumor is more characteristic of childhood.
Types of rhabdomyosarcomas
Rhabdomyosarcomas according to their internal structure are divided into types:
1. Embryonic rhabdomyosarcoma consists of round and spindle-shaped cells, the study of the cytoplasm of which shows transverse or longitudinal striation. This type of rhabdomyosarcoma is the most common. Embryonic rhabdomyosarcoma appears in children and adolescence. It is located in the neck or head, on the genitals, innasopharynx. The tumor is sensitive to radiotherapy, but prone to rapid recurrence.
2. Alveolar rhabdomyosarcoma has in its composition groups of cells of a round and oval shape, which are surrounded by partitions of connective tissue. This type of tumor is characterized by the appearance on the legs or arms, abdomen, chest, anal area or genitals. Often it can be found in adolescents and adults on the limbs. The prognosis is poor.
3. The composition of pleomorphic rhabdomyosarcoma is polymorphic spindle-shaped, ribbon-shaped, stellate cells, tumors from which can appear on the legs or arms of people. As a rule, the growth of rhabdomyosarcomas occurs quickly and does not cause pain and dysfunction. There is only an expansion of the veins. They often grow through the skin and become ulcerated, forming exophytic, bleeding tumors.
Risk factors
Among environmental factors, no such factors were found that increase the likelihood of this tumor. This distinguishes rhabdomyosarcoma from most cancers.
Due to the fact that the exact causes of the development of a tumor are not known, no advice can be given to avoid its formation. However, it should be borne in mind that with adequate treatment of rhabdomyosarcoma, patients can sometimes be completely cured.
Risk factors for fetal rhabdomyosarcoma are genetically determined diseases:
1. Li-Fraumeni syndrome, which is a rare disease in whicha trait is inherited when there is enough damage to the gene in one parent so that tumors of various types occur with a high frequency. In this pathology, the specific reactions of tissues to a tumor are inherited, when the likelihood of developing malignant tumors at a young age (up to 30 years) increases sharply.
2. Neurofibromatosis type 1 is the most common hereditary disorder that predisposes to cancer.
3. Beckwith-Wiedemann syndrome is a pathology characterized by macrosomia, macroglossia and omphalocele. It also manifests itself in children with defects in the anterior abdominal wall, hernia, neonatal hypoglycemia, and divergence of the rectus muscles.
4. Costello's syndrome is a rare disease characterized by congenital anomalies: growth retardation, coarse facial features, skin changes.
5. Noonan syndrome is a genetic disease characterized by short stature and deviations in somatic development. Can develop in the whole family or in individual members.
Babies who were overweight and tall at birth are at greater risk of developing fetal rhabdomyosarcoma than others. As a rule, the causes of embryonic rhabdomyosarcoma are unknown. A symptom of the disease is the appearance of a tumor that becomes larger and larger.
Symptoms
The symptoms of the disease are determined by the form of cancer. Urgent medical advice is required if children have any of the followingsigns of cancer:
- swelling or swelling that increases in size or does not go away, sometimes painful;
- bulging eyes;
- severe headache;
- difficulty with defecation and urination;
- blood in urine;
- hemorrhage in the rectum, throat, nose.
Diagnosis
To date, no methods have been developed to detect rhabdomyosarcoma before its first obvious symptoms appear.
The earliest signs of oncology are local swelling or induration that does not cause problems or pain at first. This symptom is characteristic of rhabdomyosarcomas of the arms, legs, and trunk.
If the tumor is localized in the peritoneum or pelvic region, there may be pain in the abdomen, vomiting or constipation. This is an embryonic rhabdomyosarcoma of the retroperitoneum. Rarely, developing in the biliary tract, rhabdomyosarcoma causes jaundice.
If this neoplasm is suspected, a biopsy should be performed to determine which type of rhabdomyosarcoma has arisen.
In most cases, rhabdomyosarcoma occurs in areas where it is easily found, such as in the nasal cavity or outside the eyeball. If the eye protrudes, or nasal discharge appears, you should immediately consult a doctor with a suspicion of a tumor in order to diagnose it at an early stage of its development. In the case when rhabdomyosarcoma appears on the surface of the body, it is easily detected without a deep examination. This is truecalled soft tissue fetal rhabdomyosarcoma.
In 30% of patients, embryonic rhabdomyosarcoma is found at an early stage, when it can be completely removed. But in the vast majority of patients, a detailed examination reveals small metastases, the treatment of which requires chemotherapy.
Embryonic rhabdomyosarcomas, located in the testicular region, are most often formed in young children and are detected by the child's parents when washing. If tumors occur in the urinary tract, they cause difficulty urinating or spotting, symptoms that should not be ignored.
Tumor stages
1. First stage. The tumor can be of any size, but it has not yet spread to the nodes of the lymphatic system and is located in one of the prognostically favorable areas of the body:
- eyes or eye area;
- neck and head (excluding tissues in the area of the brain and spinal cord);
- biliary tract and gallbladder;
- in the uterus or testicles.
Places not listed are considered unfavorable areas.
2. Second stage. The tumor is located in one of the unfavorable zones (zones that are not on the list of favorable ones). The size of the tumor does not exceed 5 cm, and there was no spread to the lymph nodes.
3. Third stage. The tumor is located in an unfavorable area, and one of the following conditions is met:
- the size of the tumor is less than 5 cm, and it has spread to the nearest lymph nodes;
- the size of the tumor exceeds 5 cm, and there isthe risk that it will spread to nearby lymph nodes.
4. Fourth stage. The size of the tumor can be any, and it has spread to the nearest lymph nodes. The cancer has spread to distant areas of the body.
Risk groups
The risk group assigned to the patient determines the likelihood of recurrence of rhabdomyosarcoma. Any child receiving treatment for fetal rhabdomyosarcoma should definitely receive additional chemotherapy to reduce the likelihood of tumor recurrence. The type of anticancer drug, dosage, and number of sessions are all determined by whether the child is at low, intermediate, or high risk.
Treatment options
Patients with fetal rhabdomyosarcoma can be treated in different ways. Treatment of malignant tumors involves separate techniques that are considered traditional. Other methods are at the stage of clinical trials. Clinical trials are used to improve existing treatments or to increase the amount of data on the latest treatments for patients with rhabdomyosarcoma. If, as a result of clinical trials, it turns out that new methods of treatment are superior to traditional ones, then the new method of treatment becomes traditional.
Because cancer tends to appear in different areas of the body, a wide variety of treatments are available. Treatmentrhabdomyosarcoma in children is supervised by a pediatric oncologist.
Among therapies, there are those that can cause side effects, even after a long time has passed since the treatment.
Surgery
The surgical method, or removal of the tumor, is widely used in the treatment of rhabdomyosarcoma. This operation is called "wide local excision". This intervention consists in removing the tumor and part of neighboring tissues along with the lymph nodes, which are also affected by rhabdomyosarcoma. Treatment sometimes consists of several surgeries. The following factors influence the decision on the purpose of the operation and its type:
- the place of the initial localization of the tumor;
- which functions of the child's body are affected by the tumor;
- tumor response to radiation therapy or chemotherapy, which can be applied as a matter of priority.
Surgical removal of the entire tumor is not possible in most children.
Embryonic soft tissue rhabdomyosarcoma tends to form in different places of the body, each of which requires its own operation. Surgical intervention is indicated in the case of rhabdomyosarcoma of the genital organs or eyes, if the biopsy confirmed the diagnosis. Chemotherapy or radiation therapy may be given before surgery to shrink large tumors that cannot be operated on to make it easier to remove the cancer.
Even if the doctor manages to remove the entire tumor, patients after the operation must be subjected to chemotherapy to suppress cancer cells,survivors. Radiation therapy is used along with chemotherapy. Treatment to reduce the risk of recurrence is called adjuvant therapy.
Radiation therapy
This type of treatment uses x-rays or other types of radiation. Radiation therapy is directed at killing tumor cells or stopping its growth. Two methods of radiation therapy have found their application in medicine - external and internal.
External uses a radiation source outside the human body to irradiate the tumor area. Internal radiation therapy, or brachytherapy, produces irradiation of a tumor with the placement of radioactive substances in close proximity to it inside the human body. It is used to treat cancers of the bladder, head, neck, prostate, vulva.
The type of radiation therapy and doses are determined by the age of the child and the type of tumor, its initial localization, as well as the presence of tumor remnants and the degree of tumor coverage of the nearest lymph nodes after surgery.
Chemotherapy
This is a type of tumor treatment that uses medicines to stop the growth of cancer cells. Chemotherapy drugs help kill these cells or prevent them from dividing. When conducting a course of systemic chemotherapy, drugs are taken orally or administered intravenously or intramuscularly. Once in the bloodstream, the drugs affect tumor cells throughout the body. With regional chemotherapy, drugs are injected directly into the organs and cavities of the body, as well as into the cerebrospinal fluid. Combination chemotherapy, which is a treatment that uses more than one anti-cancer drug, is often used. The method of chemotherapy is selected depending on the type and stage of development of the neoplasm.
Chemotherapy is indicated for every child who is being treated for rhabdomyosarcoma. It allows you to minimize the likelihood of recurrence of the disease. The choice of medicine, its dose and the number of procedures are determined by the risk group for rhabdomyosarcoma.
New treatments
New treatments for rhabdomyosarcoma in trial:
- High doses of chemotherapy combined with stem cell transplantation. The method allows organizing the replacement of hematopoietic cells that are destroyed during cancer treatment. Before treatment, immature blood cells are removed from the patient's bone marrow or blood and preserved. At the end of chemotherapy, the preserved stem cells are re-preserved and returned to the patient by infusion. In this way, blood cells are restored.
- Immunotherapy. This type of treatment uses the patient's immune system to fight cancer. The drugs used serve to increase or restore the body's natural defenses against cancer. This type of tumor treatment is called biotherapy.
- Targeted therapy. This type of therapy is directed against metastases. Targeted therapy is based on the use of special antibodies that bind to a cancer cell. These antibodies are similar to the traditional antibodies of the human body. At the same time, they representhigh-tech drugs. Thanks to targeted therapy in the treatment of "chemo", it is possible to find and attack only cancer cells without harming he althy cells. In rhabdomyosarcoma, angiogenesis inhibitors are used as targeted therapy. These drugs interfere with the formation of blood vessels in neoplasms. This causes the tumor to starve and stop growing. Angiogenesis inhibitors and monoclonal antibodies are types of agents in clinical trials to combat fetal rhabdomyosarcoma.
