Chordoma is a rare neoplasm, presumably originating from the remains of a chord. Currently, it is more often considered as malignant. Occurs near the spine, can be located at any level, from the coccyx to the base of the skull. It usually develops in the sacrococcygeal region or the occipital-basilar part of the skull. The symptoms of chordoma are determined by the localization of the tumor and the degree of damage to various nerves. Possible pain, paresis, sensitivity disorders and disorders of the pelvic organs. The diagnosis is made taking into account the data of neurological examination, radiography, CT, MRI and biopsy. Treatment – surgery, radiation therapy.
Chordoma is a tumor of varying degrees of malignancy, presumably arising from the embryonic precursor of the spine. It is always located next to the spinal column. It is usually localized in the sacrum or the base of the skull, but it can also affect other parts. Can occur at any age. Chordomas in the base of the skull are more often diagnosed at the age of 20-40 years, tumors of the sacral region – at the age of 40-60 years. Men suffer twice as often as women. The prevalence of the disease is 1-3 new cases of chordoma per year per 1 million population. The treatment is carried out by specialists in the field of oncology, neurology and vertebrology.
The causes and predisposing factors affecting the likelihood of the development of the oncological process remain unclear. It is assumed that the risk factors are cellular immunodeficiency, contacts with radioactive and chemical carcinogens in the anamnesis.
The question of malignancy of the neoplasm remains debatable. Some researchers distinguish benign and malignant forms of chordomas, others regard such tumors as relatively benign due to their slow growth and rare metastasis. At the same time, due to the high tendency to relapse and a large number of adverse outcomes, modern specialists tend to consider chordoma as a malignant process.
The chordoma is a soft single node covered with a well-defined capsule. With a malignant course, encapsulation is poorly visible. The neoplasm has a lobular structure, the section of the chordoma is translucent, light gray, areas of necrosis are visible in the tissue. Microscopy reveals cell polymorphism. Cell nuclei are small, hyperchromic. Large vacuoles are visible in the cells. In malignant chordomas, cellular anaplasia and atypical figures of mitosis are revealed.
Symptoms depend on the location, size and direction of tumor growth. Signs of damage to certain nerves usually come to the fore in the clinical picture. Chordomas located in the area of the base of the skull can spread to the area of the Turkish saddle, grow deep into the skull, in the direction of the nasopharynx or orbit. With compression of the pituitary gland, hormonal disorders may occur. Bulbar disorders are characteristic, resulting from lesions of the vagus, sublingual and pharyngeal nerve.
In patients suffering from chordoma of the base of the skull, dysarthria, swallowing disorders and voice changes (weakness, nasal twang) can be detected up to aphonia. With common chordomas, there are disturbances in the rhythm of breathing and cardiac activity due to the involvement of the respiratory and cardiovascular centers located in the medulla oblongata. Visual disturbances may occur due to compression of the optic nerve. During the spread of the process, the germination of the orbit or nasopharynx may be observed.
Sacral chordomas can spread both superficially and in the direction of the abdominal cavity or pelvis. Compression of the spinal cord and nerve roots causes pain, weakness of the lower extremities, disorders of sensitivity and movement, paresis and disorders of the pelvic organs. When the chordoma is located in an atypical place (in the cervical, thoracic or lumbar spine), pain and neurological disorders corresponding to the level of lesion are observed.
With a malignant course, there is a rapid growth of the neoplasm. The chordoma sprouts vertebrae or bones of the skull, gives metastases to regional lymph nodes, liver and lungs. In the later stages, a picture of cancer intoxication is revealed. Patients with chordoma lose weight and appetite, feel constant weakness. Mood swings, depressive disorders, anemia and hyperthermia are observed. With metastases to the lungs, shortness of breath and coughing with blood occur, with liver metastases – hepatomegaly, jaundice and ascites.
The diagnosis is made taking into account anamnesis, patient complaints, general and neurological examination data and examination results. Necessary research:
Radiography. Patients with suspected chordoma are prescribed X-ray of the skull or X-ray of the sacrococcygeal spine (depending on the localization of the neoplasm). Large areas of bone tissue destruction are found on radiographs. Sometimes, in the area of a bone defect, thin partitions are visible, dividing the cavity into several chambers. When the chordoma is located in the sacral region, an increase in the anteroposterior size of the sacrum is detected. When the tumor is localized in the skull, resorption of the sphenoid bone is noted. To determine the involvement of vessels, angiography is performed.
Tumor biopsy. The final diagnosis of chordoma is established on the basis of a biopsy and subsequent histological examination of a tissue sample. The material is taken under X-ray control. The condition of regional lymph nodes is assessed taking into account ultrasound data of the affected area.
To detect metastases in the lungs, chest X–ray and CT of the lungs are performed, to detect secondary foci in the liver – CT of the abdominal cavity and MRI of the liver. To assess the general condition of the body, patients suffering from chordoma are prescribed a general blood test, a general urine test and a biochemical blood test. During preoperative preparation, the blood group and Rh factor are determined. In the presence of somatic pathology, the patient is referred for consultation to doctors of the appropriate profile (cardiologist, gastroenterologist, endocrinologist, etc.).
Differential diagnosis of chordoma is carried out with neoplasms of the spinal cord and brain, sacral chondrosarcoma, as well as tumors of the female genital organs and colon cancer spreading to the spine.
The main method of treatment of chordoma is surgical intervention. Due to the peculiarities of the location and growth of the tumor, radical removal is possible only in a small part of patients. If radical surgical intervention is possible, a complete chordoma resection is performed together with the capsule. In other cases, palliative surgery is performed. Partial excision of the chordoma can reduce compression of nerve structures and significantly improve the quality of life of patients.
Radiation therapy for chordomas is ineffective, however, due to the great technical difficulties during surgical intervention, this method often becomes essential in the process of palliative therapy. Radiotherapy provides a reduction in the intensity of the pain syndrome and a slight reduction in the size of the chordoma. Irradiation is carried out using an X-ray machine or a gamma installation.
Along with traditional methods of radiation therapy, stereotactic surgery is used, during which the targeted effect of thin beams of gamma rays on the chordoma area is carried out. Chemotherapy is not used in the treatment of this pathology due to the resistance of the tumor to the action of chemotherapy drugs. Due to frequent recurrence, many patients require repeated operations and courses of radiation therapy.
The prognosis for chordomas is determined by the level of malignancy of the neoplasm, the prevalence of the oncological process and the success of the first surgical intervention. The average five-year survival rate for malignant forms of chordoma is about 30%. The average life expectancy of patients suffering from this pathology ranges from 5 to 10 years. The recurrence of chordoma is considered as a prognostically unfavorable sign.