To Compare Conservative Management Vs. Balloon Kyphoplasty in the Treatment of VCFs in Patients With Multiple Myeloma

Multiple myeloma (MM) accounts for 10% of the malignant haematological diseases and approximately 1% of all cancer-related deaths in Western countries. MM is characterised by the accumulation of malignant plasma cells in the bone marrow leading to impaired haematopoiesis and the highest incidence of bone involvement among the malignant diseases. MM bone disease is the result of increased destruction of bone that cannot be compensated for by new bone formation. Approximately 80% of patients with MM develop skeletal complications including bone pain, hypercalcemia, osteoporosis, osteolytic lesions and pathologic fractures. Vertebral fractures may be associated with spinal cord compression and neurological complications requiring surgery and/or radiotherapy. Osteolytic bone destruction is the most debilitating manifestation of MM, has a severe impact on patients' quality of life and is responsible for increased morbidity and mortality. Furthermore, bone resorption activity has been shown to be an independent risk factor for overall survival in patients with symptomatic MM. Moreover, myeloma-associated lytic bone lesions do not repair, even in patients who are disease free for years.

More than 50% of patients develop vertebral compression fractures (VCFs) either by the time of diagnosis or during the course of the diagnosed disease. These fractures can compromise the spinal cord and patients' height and stature, cause angulation of the spine, increasing sternum pressure, eventually resulting in sternal fractures and compromising the pulmonary capacity. 9% loss in predicted forced vital capacity is associated with each vertebral fracture. Deformity, Insomnia, depression, substantial physical, functional and psychological impairment and ultimately disability can be the result of severe vertebral compression fractures poorly managed at presentation.

Management of spinal MM bone disease

1. Bisphosphonates he use of bisphosphonates, which inhibit bone reabsorption, for the treatment of MM bone disease has led to an improvement in the quality of life for patients with MM.
2. Conservative (non-surgical) management (this is standard of care management for patients with multiple myeloma)
3. Pain relief
4. Systemic chemotherapy for Myeloma disease
5. Bed rest
6. Radiotherapy
7. Physiotherapy
8. Standard surgical procedures
9. Open surgical decompression Anterior or posterior decompression and stabilisation through internal fixation hardware and bone grafting (in <0.5% with gross spinal deformity or neurologic impairment). Higher morbidity and mortality in MM patients because of comorbid conditions related to age, disease associated end-organ damage and immunosuppression B. Minimally invasive - Cement Augmentation
10. Percutaneous Vertebroplasty
11. Percutaneous Kyphoplasty (i.e. Balloon Kyphoplasty)

COST BURDEN, HEALTH ECONOMIC IMPACT AND COST UTILITY ANALYSIS There is little evidence on differences across health systems in choice and outcome of multiple myeloma being treated with conservative treatment, chemotherapy and spinal surgery are three of many treatment options for managing multiple myeloma. The true cost associated with current therapies in addition to supportive care, is significant and poses a tremendous financial burden to both patient and health care providers.

There is therefore a need to begin to systematically optimise the guidance for treatment for this subgroup of patients especially when comparing the two treatment arms in this study, conservative treatment alone versus surgical treatment, balloon kyphoplasty.

This study will determine the cost burden, health economic impact and cost utility analysis by combining the quality of life measurements, the cost analysis will allow a calculation of the relative cost-effectiveness of conservative treatment standard of care versus standard of care plus balloon kyphoplasty.17

RATIONALE FOR CURRENT STUDY

Osteolytic lesions of vertebral bodies are frequent problems in multiple myeloma patients predisposing to severe pain, vertebral fractures and consequent neurological complications.Open surgical procedures to stabilise or correct deformed vertebral bodies are associated with major complications in this group of immunocompromised patients. In addition, open procedures are often not possible, due to a severely impaired strength of the bone tissue, which does not allow the safe application of screws and plates. As a result the standard management to reduce the local pain secondary to vertebral compression fracture has for many years been with pain relief, radiotherapy and the other elements of conservative management listed above. The development of minimally invasive procedures such as kyphoplasty and vertebroplasty has been demonstrated to be an additional effective treatment option to improve mobility and quality of life and to reduce pain.

Percutaneous vertebroplasty involves the injection of acrylic bone cement into the vertebral body in order to relieve pain and/or stabilise the fractured vertebrae and in some cases, restore vertebral height.

Percutaneous Kyphoplasty (or Balloon Kyphoplasty) is performed by inserting a balloon-like device (inflatable bone tamp) through a channel created by a hand drill in the fractured vertebrae. The tamp is positioned and inserted into the vertebral body. The balloon is then inflated slowly until normal height of the vertebral body is restored or the balloon reaches its maximum volume. The procedure is intended to restore vertebral height and correct kyphosis. It may also help to improve pulmonary and gastrointestinal function and reduce the likelihood of subsequent vertebral compression fractures. The inflation of the balloon tamp creates a cavity in the vertebral body so that when the bone tamp is withdrawn, bone cement can be injected into the cavity at a lower pressure, potentially reducing the risk of cement leakage. The cement increases the strength of the vertebra and is intended to provide pain relief.