The importance of percutaneous vertebroplasty and radiation therapy for pathological vertebral compression fractures secondary to multiple myeloma

Abstract

It is with great interest that we read the article by Chen et al. ‘‘Percutaneous vertebroplasty for pathological vertebral compression fractures secondary to multiple myeloma’’, published in the 2012 June issue of Archives of Orthopaedic and Trauma Surgery [1]. This is a thoughtful and well-designed retrospective article which evaluated the safety and complication of percutaneous vertebroplasty in the vertebral compression fractures resulting from multiple myeloma. The authors conclude that vertebroplasty remains the best option for pain relief and is effective in increasing the quality of life. They corroborate that radiation therapy needs to be performed in conjunction with vertebroplasty for malignant spinal disease, because cement injection alone does not prevent tumor growth. The article also suggested that vertebroplasty should be performed before radiation therapy, because the analgesic effects of the former are immediate and spinal stability is addressed [1]. The viewpoint of the author is right, but we have some disagreement and a few points need to be discussed with more detail. Nowadays, percutaneous vertebroplasty is a valid therapeutic option in the management of severe back pain caused by vertebral compression fractures. It is a minimally invasive, radiologically guided interventional procedure, which involves the injection of polymethylmethacrylate (PMMA) into the fractured vertebral body [2]. As we know, vertebroplasty and radiation therapy are complementary procedures to patients with pathological vertebral compression fractures; ideally, vertebroplasty immediately stabilizes the spine and relieves pain within hours, and the tumor can be further treated with radiation therapy [3–5]. The authors suggested using vertebroplasty prior to radiation therapy because the analgesic effects of the former are immediate and spinal stability is addressed. In our opinion, the important reason is that radiation therapy can lead to hardening of the bone, making the vertebroplasty more difficult to perform [6, 7]. Another reason is that malignant tissue is compressed and relocated to subcortical areas in vertebroplasty, which support local control by radiation therapy later [8]. The authors also suggested that cement injection alone cannot prevent tumor growth. In our opinion, PMMA cement has an antitumoral effect and could treat the underlying tumor cells within the affected vertebral body. This effect may be the result of the cytotoxicity, thermal effects, and ischemia produced by PMMA cement. When injected into the involved vertebral body, the space-occupying effect will inhibit tumor cell growth. More importantly, vascular structures, which are indispensable for underlying tumor cells to growth, are destroyed by the considerable exothermic reaction of the implant during its polymerization, chemical and toxic effects of the monomer, compressive effects on small nerves, and ischemic phenomena subsequent to PMMA impregnation into small vessels [9, 10]. In summary, to patients with pathological vertebral compression fractures secondary to multiple myeloma, we H. Zhao Q. Shi Z.-Y. Sun Q.-L. Gu L. Ni H.-L. Yang (&) Department of Orthopaedic Surgery, First Affiliated Hospital of Soochow University, 188 Shizi St., Suzhou 215006, Jiangsu, China e-mail: soochowspine@139.com