Synovial soft tissue sarcoma is a malignant lesion that forms from the cells of the synovial membrane, tendon, and tendon sheaths. Such a neoplasm is not limited to the capsule, as a result of which it can grow into soft tissues and into hard bone structures.
In almost half of the cases, synovial sarcoma of the soft tissues of the right ankle joint is diagnosed. Sometimes a tumor develops in the joints of the hands, forearms, neck and head, and is difficult to treat.
What is in the composition?
In the composition of such a neoplasm are cystic cavities, necrosis and hemorrhage. The pathological formation has a soft structure, but its ability to harden and calcify is not excluded. On a section during a visual examination of the sarcoma resembles a fish fillet: it has a cavernous structure and white color. Inside the formation, mucous discharge is observed, which is similar to synovial fluid. Synovial sarcoma of soft tissues differs from other malignant neoplasms in that it does not have a capsule.
This pathology is characterized by a rather aggressive course and rapid development. In most cases, it is not treatable and recurs in the next few years. Even with successful therapy, synovioma metastases can occur 5-7 years later in the lymph nodes, lung tissue, or bones.
According to statistics, both men and women equally face synovial sarcoma. Most often, such a tumor is diagnosed at the age of 15 to 25 years, however, such a disease is considered rare - it is diagnosed in three out of a million people.
Causes
The main reasons provoking the development of synovial sarcoma of soft tissues are reliably unknown. Nevertheless, some factors that can serve as an impetus for the emergence of a malignant process are identified in a separate group. These include:
- Hereditary predisposition.
- Ionizing radiation. Exposure of radiation to the body can provoke malignancy of cells in various tissues, for example, in bone.
- Injuries. Serious violations of the integrity of the joints sometimes cause oncological degeneration of cells.
- Chemical substances. The effect of carcinogens is very dangerous and can cause a malignant process.
- Immunosuppressive therapy. The implementation of this type of treatment in certain cases leads to cancer.
- Unhealthy lifestyle, bad habits.
Age of patients
Malignant synovioma is considered a disease of the young. Oncological process, according to doctors, in most cases is provoked by adverse heredity and the state of the environment. The risk group for sarcoma includes young people and adolescents living in disadvantaged ecological zones.
Symptoms of the disease
In the early stages of the malignant process, until the formation is large, clinical signs are not observed. With the progression of synovial sarcoma of soft tissues, unpleasant sensations arise in the joint area, limitation of its motor function. The softer the structure of the tumor, the less pronounced the pain syndrome.
If at this stage the specialist palpates the pathological lesion, he may mark a tumor with sizes from 2 to 15 cm. The oncological process has no boundaries, there is a weak mobility of the tumor, its dense or soft consistency. The skin above it protrudes characteristically, its color and temperature change.
A photo of synovial soft tissue sarcoma is presented.
As the synovioma grows, it destructively affects the affected tissues, they begin to collapse, the pain syndrome intensifies. The joint or limb ceases to function normally, loss of sensation or numbness occurs due to the pressure of the neoplasm on the nerve endings. If it affects the neck or head, symptoms may occur such as a foreign body feeling when swallowing, breathing problems, and a change in voice.
Common symptoms of intoxication
In addition, the patient has common symptoms of cancer intoxication, which include:
- chronic weakness;
- subfebrile condition;
- exercise intolerance;
- losing weight.
With the development of metastases and the spread of cancer cells into regional lymph nodes, their increase in volume is noted.
Synovial sarcoma of the knee, lower leg and thigh
A malignant tumor that affects the knee joint is a non-epithelial oncological neoplasm of the secondary type. The main cause of the pathological process is metastases from neighboring lymph nodes or the hip joint. If bone tissue is damaged, the doctor diagnoses osteosarcoma, and when cartilage fragments are involved in the oncological process, chondrosarcoma.
When a tumor is localized in the cavity of the knee joint, the main sign of pathology becomes pain, which usually covers the entire lower limb. Against this background, the motor functions of the leg are disturbed. If the tumor spreads outward, that is, it is localized closer to the skin, local swelling can be observed and the process diagnosed at the initial stage.
In the case of a lesion of the ligamentous apparatus by sarcoma, the leg is deprived of all functionality, since the joint is completely destroyed. With large tumors, blood flow in the tissues changes, in the lower leg there is an acute shortage of oxygen and nutrients.
Synovial sarcoma of the soft tissues of the thigh can form from almost all of its structures. Most of these neoplasms at the initial stage have a similar picture with benign tumor processes. The bulk of the pathologies of this localization are bone cancer and soft tissue tumors.
Soft sarcoma of the thigh is a rather rare pathology and most often affects men 30-60 years old.
Types of synovial sarcoma
According to the tissue structure, this tumor is divided into:
- cellular, which is formed from cells of the glandular epithelium and consists of papillomatous and cystic structures;
- fibrous, which grows from fibers that resemble fibrosarcoma in nature.
According to the morphological structure, the following types of sarcoma can be distinguished:
- alveolar;
- giant cell;
- fibrous;
- histoid;
- mixed;
- adenomatous.
WHO classification
According to the WHO classification, a tumor is divided into two types:
- Monophasic synovial sarcoma of soft tissues, when the malignant process consists of large bright and spindle-shaped cells. Differentiation of the neoplasm is poorly expressed, which significantly complicates the diagnosis of the disease.
- Biphasic synovial sarcoma of soft tissues, when the formation consists of synovial cells and has multiple cavities. It is easily determined during diagnostic procedures.
The best prognosis for the patient is noted with the development of a biphasic synovioma.
Very rarely, a species such as clear cell fasciogenic synovioma is detected. According to the main signs, it has much in common with oncomelanoma, and it is extremely difficult to diagnose it. The tumor affects the tendons and fascia and is characterized by a slow course of the pathological process.
Pathology stages
At the initial stage, the neoplasm does not exceed 5 cm and has a low degree of malignancy. The prognosis for survival in this case is very favorable and amounts to 90%.
In the second stage, the tumor has a size of more than 5 cm, but it can already affect the vessels, nerve endings, regional lymph nodes and bone tissue.
At the third stage of this oncological process, metastases in the lymph nodes are observed.
At the fourth stage, the area of the oncological process cannot be measured. In this case, important bone structures, vessels and nerves are affected. Multiple metastasis is observed. The prognosis of survival of such patients is zero. What is the treatment for synovial sarcoma of the soft tissues of the thigh or lower leg?
Treatment and prognosis
Synovioma therapy in 70% is based on its resection. Tumors in large joints: the hip, shoulder, or knee grow into the lymph nodes and the main vessels, in connection with which there are frequent relapses and metastases, so specialists resort to amputation of a limb.
In general, the treatment and prognosis of synovial soft tissue sarcoma depends on the stage of its development. At the first and second stages, the pathology is successfully treated and the prognosis of patient survival is the most favorable. At the third stage, with a successfully amputated limb and the absence of metastases, survival is predicted at 60%, at the fourth stage, when the malignant process spreads throughout the body, the prognosis is extremely unfavorable.
Surgical treatment is carried out in the following ways:
- Local removal, which is possible only at the first stage of the disease, when the examination confirmed the benign tumor. Further treatment tactics depend on the histological examination of the seized tissues and the determination of their malignancy. Relapse of the pathology is up to 95%.
- A wide excision, which is carried out with the capture of neighboring tissues with an area of approximately 5 cm. Relapses of synovial sarcoma in this case occur in 50%.
- Radical resection, in which the tumor is removed with the preservation of the organ, but bringing surgical intervention closer to amputation. In such a case, as a rule, prosthetics are used, in particular, replacement of a joint or blood vessels, plastic of nerve endings, bone resection. After the operation, all defects are hidden using autodermoplasty. Skin flaps and muscle transplantation are also used. Relapses of the process occur in about 20% of cases.
- Amputation, which is carried out with damage to the main vessel, the main nerve trunk, as well as with massive proliferation of the tumor in the tissues of the limb. The risk of relapse in this case is the lowest - 15%.
Applying surgical treatment simultaneously with chemotherapy and radiation, there are chances to save the organ in 80% of clinical situations. Removal of lymph nodes along with the focus of the pathological process is carried out provided that the study confirmed the fact of the malignancy of their tissues.
Radiation therapy
Radiation therapy for synovioma is carried out by the following methods:
- Preoperative or neoadjuvant, which is necessary to encapsulate the neoplasm, reduce its size, increase the efficiency of the operation.
- Intraoperative, which reduces the risk of relapse by 40%.
- Postoperative or adjuvant, which is used when it is impossible to carry out surgical treatment due to neglect of the pathological process and tumor decay.