Pathologic fractures in patients with multiple myeloma undergoing bisphosphonate therapy: incidence and correlation with course of disease

Predicting Risk of 30-day Postoperative Morbidity Using the Pathologic Fracture Mortality Index

INTRODUCTION

The purpose of this study was to evaluate the ability of the Pathologic Fracture Mortality Index (PFMI) to predict the risk of 30-day morbidity after pathologic fracture fixation and compare its efficacy with those of the American Society of Anesthesiologists (ASA) physical status, modified Charlson Comorbidity Index (mCCI), and modified frailty index (mFI-5).

METHODS

Cohorts of 1,723 patients in the American College of Surgeons National Surgical Quality Improvement Program database from 2005 to 2020 and 159 patients from a tertiary cancer referral center who underwent fixation for impending or completed pathologic fractures of long bones were retrospectively analyzed. National Surgical Quality Improvement Program morbidity variables were categorized into medical, surgical, utilization, and all-cause. PFMI, ASA, mCCI, and mFI-5 scores were calculated for each patient. Area under the curve (AUC) was used to compare efficacies.

RESULTS

AUCs predicting all-cause morbidity were 0.62, 0.54, and 0.56 for the PFMI, ASA, and mFI-5, respectively. The PFMI outperformed the ASA and mFI-5 in predicting all-cause ( P < 0.01), medical ( P = 0.01), and utilization ( P < 0.01) morbidities. In the 2005 to 2012 subset, the PFMI outperformed the ASA, mFI-5, and mCCI in predicting all-cause ( P = 0.01), medical ( P = 0.03), and surgical ( P = 0.05) morbidities but performed similarly to utilization morbidity ( P = 0.19). In our institutional cohort, the AUC for the PFMI in morbidity stratification was 0.68. The PFMI was associated with all-cause (odds ratio [OR], 1.30; 95% confidence interval [CI], 1.12 to 1.51; P < 0.001), medical (OR, 1.19; 95% CI, 1.03 to 1.40; P = 0.046), and utilization (OR, 1.32; 95% CI, 1.14 to 1.52; P < 0.001) morbidities but not significantly associated with surgical morbidity (OR, 1.21; 95% CI, 0.98 to 1.49; P = 0.08) in this cohort.

DISCUSSION

The PFMI is an advancement in postoperative morbidity risk stratification of patients with pathologic fracture from metastatic disease.

LEVEL OF EVIDENCE

III.

Total Hip Arthroplasty With Prophylactic Fixation of Greater Trochanter and Distal Femur in a Patient With a History of Multiple Myeloma and Breast Cancer

Multiple myeloma is the most common primary malignancy of the bone marrow and may present as bone pain and/or pathologic fracture(s) in affected patients. Treatment of bone lesions typically consists of chemotherapy and radiation and may include prophylactic fixation in patients meeting specific criteria. This report reviews a case of a 74-year-old female with a history of multiple myeloma and breast cancer, previously treated with chemotherapy and radiation, who sustained a pathologic femoral neck fracture with associated ipsilateral lesions of the femoral shaft and peritrochanteric region. This patient received a total hip arthroplasty with a greater trochanteric claw plate and extended femoral stem for prophylactic fixation of the distal femur. In this report, the current literature surrounding the use of extended femoral stems for prophylactic fixation of femoral diaphyseal lesions will be reviewed and the above case will be presented. This case serves as a bridge between orthopedic oncology and arthroplasty as an extended femoral stem was used to prevent future pathologic fracture of distal femur lesions.

Treatment of Pathological Fracture of Radius due to Multiple Myeloma with Elastic Intramedullary Nail and Cement Augmentation: Expanding the Indications of Elastic Nails

Pathological fractures of the proximal radius are exceedingly rare. Here, a case of an 81-year-old female diagnosed with multiple myeloma 15 years ago who suffered a pathological fracture of her left proximal radius is presented. Due to the fracture's proximity to the elbow joint and the lack of adjacent healthy bone tissue, a resourceful surgical intervention was implemented using a pediatric flexible nail supplemented by polymethacrylate cement injection. Six weeks post-operatively, the patient had alleviation of the pain with fully functional forearm. This novel approach could possibly aid in the treatment of other long bone pathological fractures due to neoplastic metastases.

Multiple Myeloma: Challenges Encountered and Future Options for Better Treatment

Multiple myeloma (MM) is a malignant hematological disease. The disease is characterized by the clonal proliferation of malignant plasma cells in the bone marrow. MM accounts for 1.3% of all malignancies and has been increasing in incidence all over the world. Various genetic abnormalities, mutations, and translocation, including epigenetic modifications, are known to contribute to the disease's pathophysiology. The prognosis is good if detected early, or else the outcome is very bad if distant metastasis has already occurred. Conventional treatment with drugs poses a challenge when there is drug resistance. In the present review, we discuss multiple myeloma and its treatment, drug resistance, the molecular basis of epigenetic regulation, the role of natural products in epigenetic regulators, diet, physical activity, addiction, and environmental pollutants, which may be beneficial for clinicians and researchers.

Vertebral augmentation

Vertebral augmentation, including vertebroplasty and kyphoplasty, is a minimally invasive, image-guided procedure in which cement (typically polymethylmethacrylate (PMMA)) is injected into a vertebral body to treat painful fractures. The majority of vertebroplasty and kyphoplasty procedures are performed to treat symptomatic osteoporotic compression fractures refractory to conservative medical therapy; however, there is also evidence to suggest the benefits of augmentation in patients with refractory pain in the acute compression setting. The primary goal of augmentation is decreasing pain and improving a patient's functional status. The secondary goal of augmentation is vertebral body stabilization. This chapter outlines the indications, contraindications, techniques, and literature behind vertebral augmentation.

Evaluation of the Relevance of Surgery in Patients with Multiple Myeloma Harboring Symptomatic Spinal Involvement: A Retrospective Case Series

BACKGROUND

Multiple myeloma spinal involvement can lead to bone fractures and neurologic impairment that can severely alter quality of life. The role of surgery is controversial, given its high morbidity, and the lack of evidence. We hereby aim to evaluate efficacy and safety of surgery in the management of symptomatic spinal lesions in patients with multiple myeloma.

METHODS

We included all patients operated on for a myeloma-related spinal lesion in our institution between 2007 and 2015. Demographic, clinical, and surgical data were collected as well as hematologic profiles. We retrospectively assessed the surgical success of the procedures, if at 3 months the patient fulfilled the following 4 criteria: pain relief, ability to walk, spinal stability, and no relevant morbidity.

RESULTS

Thirty-six men and 19 women, with a median age of 62 years, were included. Seventeen patients underwent an emergency intervention, whereas 38 patients underwent elective surgery. At 3 months, 88.2% and 96.1%, respectively, of patients experienced pain relief and were able to walk. Spinal stability was considered satisfactory for 94.1% of patients. We reported 8 major complications in 8 patients. Altogether, 34 patients (61.8%) fulfilled all criteria for surgical success. An International Staging System score of 1 and the absence of previous chemotherapy were significantly associated with surgical success.

CONCLUSIONS

Management of myeloma-related spine lesions requires a multidisciplinary approach. Surgery rapidly provides both decompression and stabilization. Using a strict patient-specific evaluation, we reported rewarding functional results, with acceptable morbidity. Surgery for multiple myeloma vertebral lesions seems to be a valuable option for carefully selected patients.

Stability of Spinal Bone Lesions in Patients With Multiple Myeloma After Radiotherapy-A Retrospective Analysis of 130 Cases

BACKGROUND

The objective of the present retrospective analysis was the response evaluation regarding bone density and stability of patients with osteolytic spinal bone lesions due to multiple myeloma after palliative radiotherapy (RT).

PATIENTS AND METHODS

Patients with multiple myeloma who had undergone spinal RT from March 2003 to May 2016 were analyzed before and 3 and 6 months after RT. Assessment of spinal stability and bone density was performed using the internationally recognized Taneichi scoring system and measurement of bone density using computed tomography imaging-based Hounsfield units. For statistical analysis, we used the Bowker test, McNemar test, and κ statistics to detect possible asymmetries in the distribution of the Taneichi score over time. We used the Student t test for comparison of the density values (Hounsfield units) before and after treatment. Toxicity was evaluated using the Common Terminology Criteria for Adverse Events, version 4.0. Additionally, overall survival was calculated using the Kaplan-Meier method.

RESULTS

We evaluated 130 patients (69% male; 31% female) with multiple myeloma and a median age of 58 years. The median follow-up period was 41 months. Before treatment, 51% of the lesions were classified as unstable. At 3 and 6 months after RT, this rate had decreased to 41% (P = .0047) and 24% (P = .2393), respectively. The computed tomography measurements showed a significant increase in bone density at 3 and 6 months after RT. Acute RT-related grade 1 and 2 complications were detected in 34% of patients. Late side effects (grade 1-2) were detected in 23% of the patients. No severe grade 3 or 4 acute or late toxicities were identified. The median overall survival was 19.7 months for all patients and 6.6 months for patients with a Karnofsky performance score of ≤ 70%.

CONCLUSION

To the best of our knowledge, ours is the first report to analyze the bone density and stability in patients with multiple myeloma after RT using a validated scoring system and computed tomography imaging. Palliative RT is an effective method resulting in a significant increase in bone density for local response and stability without severe RT-related toxicity. Furthermore, recalcification could already be detected at 3 months after treatment.

Imaging of Multiple Myeloma

Multiple myeloma is the most common bone malignancy. Imaging plays an important role in identifying the extent of the disease, disease process, guiding biopsies, and diagnosing associated spinal and intracranial complications. Multiple myeloma and related plasma cell proliferative disorders have a diverse set of clinicopathologic findings and on neuroimaging present unique and diverse findings from the disease and from complications of the disease and treatment, which are valuable for clinicians and radiologists.

Assessment of Bone Fragility in Patients With Multiple Myeloma Using QCT-Based Finite Element Modeling

Multiple myeloma (MM) is a malignant plasma cell disease associated with severe bone destruction. Surgical intervention is often required to prevent vertebral body collapse and resulting neurological complications; however, its necessity is determined by measuring lesion size or number, without considering bone biomechanics. Finite element (FE) modeling, which simulates the physiological loading, may improve the prediction of fragility. To test this, we developed a quantitative computed tomography (QCT)-based FE model of the vertebra and applied it to a dataset of MM patients with and without prevalent fracture. FE models were generated from vertebral QCT scans of the T₁₂ (T₁₁ if T₁₂ was fractured) of 104 MM patients, 45 with fracture and 59 without, using a low-dose scan protocol (1.5 mm slice thickness, 4.0 to 6.5 mSv effective dose). A calibration phantom enabled the conversion of the CT Hounsfield units to FE material properties. Compressive loading of the vertebral body was simulated and the stiffness, yield load, and work to yield determined. To compare the parameters between fracture and nonfracture groups, t tests were used, and standardized odds ratios (sOR, normalized to standard deviation) and 95% confidence intervals were calculated. FE parameters were compared to mineral and structural parameters using linear regression. Patients with fracture showed lower vertebral stiffness (-15.2%; p = 0.010; sOR = 1.73; 95% CI, 1.11 to 2.70), yield force (-21.5%; p = 0.002; sOR = 2.09; 95% CI, 1.27 to 3.43), and work to yield (-27.4%; p = 0.001; sOR = 2.28; 95% CI, 1.33 to 3.92) compared to nonfracture patients. All parameters correlated significantly with vBMD (stiffness: R²  = 0.57, yield force: R²  = 0.59, work to yield: R²  = 0.50, p < 0.001), BV/TV (stiffness: R²  = 0.56, yield force: R²  = 0.58, work to yield: R²  = 0.49, p < 0.001), and Tb.Sp (stiffness: R²  = 0.51, yield force: R²  = 0.53, work to yield: R²  = 0.45, p < 0.001). FE modeling identified MM patients with compromised mechanical integrity of the vertebra. Higher sOR values were obtained for the biomechanical compared to structural or mineral measures, suggesting that FE modeling improves fragility assessment in these patients. © 2016 American Society for Bone and Mineral Research.

Association of osteolytic lesions, bone mineral loss and trabecular sclerosis with prevalent vertebral fractures in patients with multiple myeloma

PURPOSE

In patients with multiple myeloma (MM), computed tomography is widely used for staging and to detect fractures. Detecting patients at severe fracture risk is of utmost importance. However the criteria for impaired stability of vertebral bodies are not yet clearly defined. We investigated the performance of parameters that can be detected by the radiologist for discrimination of patients with and without fractures.

METHODS AND MATERIALS

We analyzed 128 whole body low-dose CT of MM patients. In all scans a QCT calibration phantom was integrated into the positioning mat (Image Analysis Phantom(®)). A QCT-software (Structural Insight) performed the volumetric bone mineral density (vBMD) measurements. Description of fracture risk was provided from the clinical radiological report. Suspected progressive disease (PD) was reported by the referring clinicians. Two radiologists that were blinded to study outcome reported on the following parameters based on predefined criteria: reduced radiodensity in the massa lateralis of the os sacrum (RDS), trabecular thickening and sclerosis of three or more vertebrae (TTS), extraosseous MM manifestations (EOM), visible small osteolytic lesions up to a length of 8mm (SO) and osteolytic lesions larger than 8mm (LO). Prevalent vertebral fractures (PVF) were defined by Genant criteria. Age-adjusted standardized odds ratios (sOR) per standard deviation change were derived from logistic regression analysis and area under the curve (AUC) from receiver operating characteristics (ROC) analyses were calculated. ROC curves were compared using the DeLong method.

RESULTS

45% of the 128 patients showed PVF (29 of 75 men, 24 of 53 women). Patients with PVF were not significantly older than patients without fractures (64.6 ± 9.2 vs. 63.3 ± 12.3 years: mean ± SD, p=0.5). The prevalence of each parameter did not differ significantly by sex. Significant fracture discrimination for age adjusted single models was provided by the parameters vBMD (OR 3.5 [1.4-8.8], AUC=0.64 ± 0.14), SO (sOR 1.6[1.1-2.2], AUC=0.63 ± 0.05), LO (sOR 2.1[1.1-4.2] AUC=0.69 ± 0.05) and RDS (sOR 2.6[1.6-4.7], AUC=0.69 ± 0.05). Multivariate models of these four parameters showed a significantly stronger association with the development of PVF (AUC=0.80 ± 0.04) than single variables. TTS showed a significant association with PVF in men(sOR 1.5 [0.8-3.0], AUC=0.63 ± 0.08), but not in women (sOR 2.3[1.4-3.7], AUC=0.70 ± 0.07). PD was significantly associated with PVF in women (sOR 1.9[1.1-3.6], AUC=0.67 ± 0.08) but not in men (sOR 1.4[0.9-2.3], AUC=0.57 ± .07). EOM were not associated with PVF (sOR 1.0[0.4-2.6], AUC=0.51 ± .05).

CONCLUSION

In multiple myeloma, focal skeletal changes in low dose CT scans show a significant association with prevalent vertebral fractures. The combination of large osteolytic lesions and loss in radiodensity as can be detected with simple CT Hounsfield measurements of the os sacrum or BMD measurements showed the strongest association to fractures and may be of value for prospective studies.

Association of QCT Bone Mineral Density and Bone Structure With Vertebral Fractures in Patients With Multiple Myeloma

Computed tomography (CT) is used for staging osteolytic lesions and detecting fractures in patients with multiple myeloma (MM). In the OsteoLysis of Metastases and Plasmacell-infiltration Computed Tomography 2 study (OLyMP-CT) study we investigated whether patients with and without vertebral fractures show differences in bone mineral density (BMD) or microstructure that could be used to identify patients at risk for fracture. We evaluated whole-body CT scans in a group of 104 MM patients without visible osteolytic lesions using an underlying lightweight calibration phantom (Image Analysis Inc., Columbia, KY, USA). QCT software (StructuralInsight) was used for the assessment of BMD and bone structure of the T11 or T12 vertebral body. Age-adjusted standardized odds ratios (sORs) per SD change were derived from logistic regression analyses, and areas under the receiver operating characteristics (ROC) curve (AUCs) analyses were calculated. Forty-six of the 104 patients had prevalent vertebral fractures (24/60 men, 22/44 women). Patients with fractures were not significantly older than patients without fractures (mean ± SD, 64 ± 9.2 versus 62 ± 12.3 years; p = 0.4). Trabecular BMD in patients with fractures versus without fractures was 169 ± 41 versus 192 ± 51 mg/cc (AUC = 0.62 ± 0.06, sOR = 1.6 [1.1 to 2.5], p = 0.02). Microstructural variables achieved optimal discriminatory power at bone thresholds of 150 mg/cc. Best fracture discrimination for single microstructural variables was observed for trabecular separation (Tb.Sp) (AUC = 0.72 ± 0.05, sOR = 2.4 (1.5 to 3.9), p < 0.0001). In multivariate models AUCs improved to 0.77 ± 0.05 for BMD and Tb.Sp, and 0.79 ± 0.05 for Tb.Sp and trabecular thickness (Tb.Th). Compared to BMD values, these improvements of AUC values were statistically significant (p < 0.0001). In MM patients, QCT-based analyses of bone structure derived from routine CT scans permit discrimination of patients with and without vertebral fractures. Rarefaction of the trabecular network due to plasma cell infiltration and osteoporosis can be measured. Deterioration of microstructural measures appear to be of value for vertebral fracture risk assessment and may indicate early stages of osteolytic processes not yet visible.

Is retention of zoledronic acid onto bone different in multiple myeloma and breast cancer patients with bone metastasis?

Zoledronic acid (Zol) is used to treat bone disease in both multiple myeloma (MM) and breast cancer patients with bone metastasis (BC). However, bones of MM and BC patients show a difference in retention of the bisphosphonate used for bone scintigraphy. Therefore, we hypothesized that disease-specific factors may differently influence Zol retention in MM and BC patients. We tested this hypothesis in an investigator initiated phase II clinical trial in which we compared the whole-body retention (WBrt) of Zol in a cohort of 30 multiple myeloma (MM) and 30 breast cancer (BC) (20 Zol naive and 40 with six or more previous administrations). On average, 62% of the administered Zol was retained in the skeleton of both MM and BC patients and independently of the number of treatments. WBrt of Zol did not correlate with cross-linked C-telopeptide (CTX) levels, but linear regression analyses showed that WBrt of Zol correlated with bone-specific alkaline phosphatase (bALP) levels in BC (p = 0.001), and with CTX/bALP in Zol naive MM patients (p = 0.012). Especially in BC patients, WBrt correlated with age (p = 0.014) independently of kidney function. In MM patients WBrt was found to primarily correlate with the extent of bone disease (p = 0.028). Multivariate linear regression analyses of the entire cohort pointed out that WBrt of Zol was best predicted by age (p < 0.000), osseous lesions (p < 0.001), and the preceding Zol dosing (p < 0.005) (r(2)  = 0.97). Comparing bone scintigrams with CT/X-ray images showed a poor correlation between sites of active bone disease and binding of scintigraphy bisphosphonate in 36% of MM patients and in 13% of BC patients. We conclude that WBrt of Zol is primarily determined by two non-disease related factors and only one disease related, but that there may be differences in retention or drug delivery at individual sites of bone disease between MM and BC patients. In order to find the optimal dosing of Zol, these observations should be taken into account.

Role of whole-body 64-slice multidetector computed tomography in treatment planning for multiple myeloma

PURPOSE

The authors evaluated the role of whole-body 64-slice multidetector computed tomography (WB-MDCT) in treatment planning for multiple myeloma.

MATERIAL AND METHODS

This was a prospective study of 28 consecutive patients with multiple myeloma (19 men, nine women; age range, 51-73 years; mean age, 60 years) who underwent WB-MDCT and conventional radiography (CR) of the skeleton. The images were interpreted for the presence of bony lesions, medullary lesions, fractures and extraosseous lesions. We evaluated any changes in treatment planning as a result of WB-MDCT findings.

RESULTS

WB-MDCT was superior to CR for detecting bony lesions (p=0.001), especially of the spine (p=0.001) and thoracic cage (p=0.006). WB-MDCT upstaged 14 patients, with a significant difference in staging (p=0.002) between WB-MDCT and CR. Medullary involvement either focal (n=6) or diffuse (n=3) had a positive correlation with the overall score (r=0.790) and stage (r=0.618) of disease. Spine fractures were better detected at WB-MDCT (n=4) than at CR (n=2). Extraosseous soft tissue lesions (n=7) were detected only at WB-MDCT. Findings detected at the WB-MDCT led to changes in the patient's treatment plan in 39% of cases. Upstaging of seven patients (25%) altered the medical treatment plan, and four of 28 (14%) patients required additional radiotherapy (7%) and vertebroplasty (7%).

CONCLUSIONS

We conclude that WB-MDCT has an impact on treatment planning and prognosis in patients with multiple myeloma, as it has high rate of detecting cortical and medullary bone lesions, spinal fracture and extraosseous lesions. This information may alter treatment planning in multiple myeloma due to disease upstaging and detection of spine fracture and extraosseous spinal lesions.