Diagnostic And Surgical Strategy For The Skeleton-related Events Associated With Plasma Cell Myeloma

BackgroundPlasma cell myeloma is a malignant tumor characterized by abnormal proliferation of monoclonal plasmacytes and secretion of monoclonal immunoglobumin. In some countries, plasma cell myeloma ranks as the second most common hematological malignancies and among which, multiple myeloma (MM), could invade skeleton system, often beginning from spongy bone of axial skeleton. The incidence of MM is about 0.7-3.3/100000 while SM only accounts for approximate 2% of all myeloma patients. It was reported that about 2/3 of SM eventually progressed to MM. The main treatment methods of myeloma included chemotherapy, radiotherapy and hematopoietic stem cell transplantation. The incidence of myeloma is growing with the population aging. The cytokines secreted by myeloma could enhance the activity of osteoclast and reduce the activity of osteoblast, and therefore cause the imbalance of bone resorption and bone formation, which would induce generalized osteoporosis and bone destruction. Eventually, it could lead to bone pain, hypercalcemia and other skeleton-related events (SREs) such as pathological fracture, spinal instability and spinal cord compression. Without effective corresponding treatment, about half of patients with myeloma would suffer at least one kind of SREs. These events greatly influence the quality of life and prognosis of patients with myeloma. Some studies pointed out that the mortality of patients with pathological fractures is approximately 20% higher than those without any SREs. In China, there was one clinical study pointed out that the clinical department which most myeloma patients visited firstly was orthopedic department (29.92%).Up to now, with regard to the necessity of surgery, indications for different surgical method, the influence of surgical intervention to the quality of life and prognosis for myeloma patients, controversy still exist. Some investigators demonstrated that proper surgery could extend the lifespan of myeloma patients while some insisted that for patients with solitary myeloma, surgery is not indispensable.AimBy collecting and discussing the data (such as the clinical manifestation, diagnostic methods, surgical treatment indications, surgical options, as well as recovery and prognosis of patients after surgery) of myeloma patients with skeleton-related events (SREs) as the main clinical sign diagnosed and treated in the department of orthopedics of Qilu hospital affiliated to Shandong University, we aimed to systematically appraise the safety and necessity of different surgical method and investigate the comprehensive surgical regimen for SREs of plasma cell myeloma and therefore to provide reference for the treatment of patients with myeloma in the department of orthopedics, and avoid misdiagnosis, inadequate and excessive treatment.MethodWe followed up 88 patients with plasma cell myeloma admitted to the department of orthopedics of Qilu hospital affiliated to Shandong University and received operations from May,2005 to May,2015, which consisted of 41 males and 47 females with the age ranging from 38 to 76 years (average age of 58.4 years) and retrospectively analyzed their medical history and surgical procedures.78 cases were admitted for spinal events,9 patients for femoral events and 1 for tibial event. Eventually,85 cases were diagnosed as multiple myeloma and 3 cases were diagnosed as solitary myeloma; 51 cases were firstly diagnosed at the department of orthopedics and 37 cases at other department. The main clinical manifestations that most patients presented included cervical, lumbar, back or limb pain, damaged neural function and pathological fracture. 12 patients possessed damage of spinal cord function and according to Frankel classification,5 cases were classified as B-grades and 7 cases were classified as C-grades. All patients were recommended to accept surgical treatment. The related data including the visual analogue scale score (VAS), Oswestry disability index(ODI), Frankel score, Kamofsky sore and Mirel score before as well as two weeks and half year after the surgery were collected and appraised with paired t-test by using SPSS. In order to evaluate the effect of operations, we followed up these patients for a long term and calculate the total survival rate by using Kaplan-Meier method.ResultThe minimal follow-up time was six months. All deaths occurred in patients with multiple lesions in spine.20 patients involving 32 diseased vertebra accepted posterior vertebroplasty (PVP) or posterior kyphoplasty (PKP). For these patients, the VAS before operations were 4-8 with average score of being 6.45±1.05, the VAS 24 hours after operations were 0-3 with average score of being 1.05 ±0.89 and the VAS half years after operations were 1.35 ±0.67; the mean Oswestry disability index (ODI) before the operations was 68.1±8.74, the ODI two weeks after operations was 15.0±8.17 and the ODI half years after operations was 17.1±7.50. These differences were statistically significant (p<0.01). Among the patients that were admitted for vertebral lesions and accepted open operations,49 cases were operated through posterior approach, in which,47 cases received vertebral canal decompression and pedicle screw internal fixation (11 cases also received open vertebroplasty simultaneously) and other 2 cases received total vertebral resection, titanium mesh/bone cement filling and pedicle screw fixation. Five open surgeries operated through anterior approach were vertebral tumor resection, titanium mesh/bone cement implantation, steel/titanium plate internal fixation and the remaining 4 cases were operated through combined anterior and posterior approach. For these patients receiving open operations, the mean VAS before operations was 6.47+ 1.23 and the mean VAS half years after operations were 1.32+0.71; the mean Kamofsky score before the operations was 39.82+8.48 and the mean Kamofsky score half years after operations was 77.76+9.74. These differences were statistically significant (p<0.01). For 12 patients with damaged spinal cord functions,9 cases were relieved to D-grades from B-or C-grades; 3 cases were classified as E-grades and their pains were alleviated and muscle strength was enhanced. For two patients with solitary myeloma, their manifestations disappeared and no recurrence happen at the end of follow-up. Among 9 patients admitted for femoral lesions,7 cases underwent tumor scraping, bone cement filling and internal fixation, and 2 cases of lesions located in the proximal femur underwent tumor resection, femoral head prosthesis/total hip arthroplasty. The follow-up time of patients with femoral lesions were 14-47 months with average follow-up time being 31.75 months. During follow-up, there were 1 withdrawals and no recurrence or death occurs. The one admitted for tibial lesions were diagnosed as solitary myeloma and underwent tumor resection and custom-made prosthesis replacement. We followed up this patient for 12 months and no recurrence or complications occur.Conclusion1.Plasma cell myeloma is a hematological system diseases. The most common involved position are bones. It can cause pain, pathological fractures and damage of spinal cord and neural functions. A subset of patients will require surgical treatment at the department of orthopedics. Preventing and treating skeleton-related events is the task of doctors in the department of orthopedics.2.Spine is the most commonly involved site and lesions of long bones are rare.3.Methods of operations should be chosed according to the tumor location, bone destruction, spinal cord injury, clinical manifestations and systemic status.4.For spinal lesions caused by plasma cell myeloma, if patients presents as simple pathological fracture or near fracture, especially accompanied with pain, they can accept posterior posterior vertebroplasty or posterior kyphoplasty. Meanwhile, spinal decompression and spinal fixation open surgery is indispensable for patients with unstable spine or injured neural and spine cord function. Tumor resection is necessary under a small number of cases.5.For lesions located at long bone with a pathologic fracture or a high risk of fracture, if the lesion involves the end of the joint, endoprostheses replacement can be implemented and if the lesions involves the shaft of the bone, internal fixation and bone cement fulfillment can be implemented.6.Multiple myeloma is a systemic disease and most operations are palliative rather than radical.