Extradural Tumor - Causes, Symptoms, Diagnosis, and Treatment

Introduction:

The tumors that are found in the spine are called spinal tumors. It can be primary or metastatic tumors. Primary tumors are those arising from the spine, whereas metastasizing tumors spread to the spine from different organs like the lungs, breasts, or prostate. There are three groups of spinal tumors based on where the tumor is located in relation to the spinal cord. Extradural tumors, intradural tumors, and intramedullary tumors.

What Is an Extradural Tumor?

The spinal cord is covered by a thick fibrous substance called the dura. Extradural tumor or epidural tumor is formed in the spinal column. Extradural tumors can affect the vertebrae, but it is not associated with spinal cord tumors. These tumors are found in the epidural space between the dura membrane and the spinal cord.

What Are the Causes of Extradural Tumors?

The actual cause of the extradural tumor is unknown. Most tumors are metastatic, and they spread from other organs. The probable cause of primary tumor can be:

• Defect in any of the genes controlling growth.

• Chemical exposure.

• Neurofibromatosis type 2 or due to some inherited syndromes.

What Are the Symptoms of an Extradural Tumor?

The signs and symptoms of an extradural tumor are:

• Back pain or pain in the cervical region of the spine.

• Weakness and fatigue in arms and legs.

• Pinching sensation in the nerves.

• Involuntary bowel and bladder functions.

• Sudden weight loss.

• Nausea and vomiting.

• Fever and chills.

• Paralysis is seen in different body parts.

• Radiating back pain to the legs, hands, or hip.

• Numbness in legs or arms.

• Walking difficulty.

What Are the Types of Extradural Tumors?

The primary extradural tumors can be benign or malignant. The types of tumors seen in the extradural space are described below.

1. Benign Tumors -

• Aneurysmal Bone Cyst - Aneurysmal bone cyst is a benign tumor of the bone covered by a thin wall made of bone filled with blood lesions that tend to grow. Other than the spine, they can be seen in the knee and pelvis region. They are aggressive benign tumors that grow fast. The cause of this tumor is unknown but commonly attributed to gene mutations. The treatment includes curettage of the lesion, removing all tumor cells and the cyst lining. Sometimes a bone graft is placed to replace the removed bone.

• Giant Cell Tumor - Giant cell tumor is an aggressive benign tumor and is usually rare. They are seen at the end of long bones like the femur or tibia. Commonly seen in females. In the microscopic examination of this tumor, the cells appear large, so the name giant cell tumor is used. The giant cell tumor is usually removed surgically using curettage (scraping the tumor out) and replaced with a bone graft.

• Hemangioma - They are rare. It is a congenital vascular defect that is round in shape and seen in the lumbar spinal region. Microscopically they are seen as abnormal vascular changes. Treatment for hemangioma is complete removal.

• Osteoblastoma - It is also an aggressive type of tumor and is very rare. Treatment includes complete resection of the tumor to prevent its transformation into a malignant tumor.

• Osteochondroma - Osteochondroma can originate in any part of the spine. It is the tumor growth seen on the cartilage and the bone. Treatment of this tumor depends upon the severity, intralesional (without involving margins), or en bloc resection (complete removal with margin and normal tissue).

• Osteoid Osteoma - These are benign tumors of the bone. They are characterized by inflammation of the bone and severe consistent pain, which increases at night. The treatment of osteoid osteoma is surgical excision.

2. Malignant Tumors -

• Chondroma - They are very rare tumors. It is seen in the lumbar region of the spine. It is a tumor of the cartilage. Surgical removal of the chondroma is the treatment to prevent its recurrence.

• Chondrosarcoma - These are seen in the thoracic spine and are malignant tumors. En-bloc resection of the tumor is the treatment of choice for chondrosarcoma. Spinal reconstruction is needed after the en-bloc tumor resection.

• Ewing’s Sarcoma - It is a malignant tumor of the bone. It is a metastasizing cancer, and the treatment option is surgical removal of the tumor to prevent further spread of the tumor.

• Lymphoma - Primary spinal epidural lymphoma is a type of lymphoma seen in epidural space. The lymphoma is treated with surgical removal of the tumor. Radiotherapy and chemotherapy are used to prevent the recurrence of this tumor.

• Osteosarcoma - Spinal osteosarcoma is rare. Intolerable pain is a common symptom of osteosarcoma. En bloc resection is the treatment of choice.

• Plasmacytoma With Multiple Myeloma - Multiple myeloma is the cancer of plasma cells or white blood cells. Monoclonal plasma cells accumulate in the bone marrow. Plasmacytoma with multiple myeloma is a rare malignant tumor. Surgical therapy is not indicated and chemotherapy is considered the treatment of choice in plasmacytoma with multiple myeloma.

How Is Extradural Tumor Diagnosed?

The initial diagnosis of the extradural tumor is by assessing the signs and symptoms. Detailed medical and family histories are also noted. Radiological tests confirm the tumor.

• X-Ray - Using less ionizing radiation, images of the vertebrae and joints are produced. X-rays can show any infections, fractures, or abnormal growth of cells in the spinal region.

• Computed Tomography (CT) Scan - Using high radiation and computer technology, images of the vertebrae and joints are produced. It produces slices or a cross-sectional view of the bony structures.

• Magnetic Resonance Imaging (MRI) - Using a strong magnetic field and computer technology, three-dimensional images of the body parts, spinal cord, and nerve roots are produced.

• Bone Scan - Using nuclear imaging techniques to diagnose various bone diseases, infections, and tumors of the bone.

• Biopsy - A tissue sample is taken from the abnormal growth to determine whether the tumor is malignant or benign and to stage the tumor.

What Is the Treatment for Extradural Tumors?

The treatment for an extradural tumor depends on the stage to which the tumor has progressed. The staging of the tumor is done by assessing the imaging results and biopsy. Non-surgical or surgical treatment can be done for extradural tumors depending on the stage of the tumor.

1. Non-surgical Treatments - Asymptomatic tumors are monitored by regular MRI scans.

• Chemotherapy uses high dosages of drugs to kill cancer cells. It can be used orally or systemically by injecting the drug into the veins.

• Radiation therapy uses high radiation doses to kill cancer cells and prevent their growth. Radiation therapy can be done by two methods. External beam radiation uses an external source of radiation, usually by a machine, and an internal beam of radiation or brachytherapy, in which radiation is targeted to specific sites with the help of radiation seeds inserted inside the body, which produces the radiation.

2. Surgical Treatments - The metastasized tumor cannot be completely removed, so along with the surgical removal of the tumor, radiotherapy is also advised to prevent the growth of the tumor.

• Non-metastatic or primary tumors are completely removed to prevent their recurrence. This method of complete removal of the tumor without breaking the capsule is called en bloc resection.

• In a metastatic tumor, surgery is often contraindicated, and palliative care is suggested for such cases. Surgery is pursued in cases where there is spinal cord compression, uncontrollable pain, or when the tumor is not responding to chemotherapy or radiation therapy.

Conclusion:

Extradural tumors are common tumors of the spinal cord. They account for 60 percent of all spine tumors. But due to the aggressive nature of the disease, it is very difficult to treat these tumors. It is challenging to get tumor margins in metastasizing spinal tumor surgical procedures. Treatment with molecular drugs can increase survival rates.