Local radiotherapy for palliation in multiple myeloma patients with symptomatic bone lesions

Radiation for Multiple Myeloma in the Era of Novel Agents: Indications, Safety, and Dose Selection

Survival outcomes for multiple myeloma (MM) have drastically improved over the past two decades with the advent of highly effective biologic agents and integration of autologous stem cell transplant (ASCT) for select patients. Despite these advances, MM remains an incurable disease and duration of remission decreases with each relapse. Palliative radiotherapy (RT) for MM, including treatment of pain, relief of compression, and prevention of fracture, is highly effective and generally well tolerated. Though RT can be delivered concurrently with biologic agents, caution should be exercised for potential added hematologic toxicity that may disrupt systemic therapy, especially in heavily pretreated patients, who have limited bone marrow reserve. In this review, we discuss the safety of RT with biologic agents (proteasome inhibitors, immunomodulators, monoclonal antibodies), review indications for palliative RT in MM, and present a framework for how to personalize RT based on goals of treatment, classification of uncomplicated versus complicated lesions, and patient and lesion characteristics. Additionally, we discuss the emerging role of bridging RT prior to chimeric antigen receptor (CAR) T-cell therapy.

Radiation Therapy Can Be Safely Incorporated into Pretransplantation Treatment Regimens for Patients with Multiple Myeloma

Primary treatment of multiple myeloma (MM) often involves systemic induction therapy (SIT) followed by autologous stem cell transplantation (ASCT). Radiation therapy (RT) is sometimes used for palliation; however, many practitioners avoid RT out of concern that future peripheral blood progenitor cell (PBPC) collection required for ASCT may be compromised. In this study, we retrospectively examined the possible effect of RT on PBPC collection. We reviewed the charts of 732 patients with MM treated with RT at our institution from 1999 to 2017, including patients who received RT prior to PBPC collection for planned ASCT. RT plans (both MM and non-MM RT) were reviewed to estimate the percentage of bone marrow (BM) treated using published estimates of skeletal BM distribution. Statistics were performed using Pearson correlation and the t-test. The 732 MM patients included 485 planned for ASCT; of these, 223 received RT prior to PBPC collection and were included in the final cohort. The median age at PBPC collection was 59 years (range, 33 to 80 years). For SIT, patients received combination regimens including the following agents: bortezomib (142 patients; 64%), lenalidomide (111 patients; 50%), and alkylators (46 patients; 21%). Nine patients (4%) received dexamethasone alone. The median cumulative %BM treated per patient was 6.7 (range .0 to 47.4). The median RT dose was 24 Gy (range, 10.0 to 75.6 Gy). Mobilization was performed using granulocyte-colony stimulating factor (G-CSF) alone (189 patients; 85%), G-CSF with plerixafor (15 patients; 7%), or chemotherapy (19 patients; 9%). A median of 7.8 × 106 CD34+/kg PBPCs (range, .5 to 54.8× 106 CD34+/kg) were collected in a median of 3 (range, 1 to 9) apheresis procedures. One hundred ninety-six patients (99%) collected ≥2.0 × 106 CD34+/kg PBPCs, and 166 (83%) collected >5.0 × 106 CD34+/kg PBPCs. The number of PBPCs collected was not associated with %BM treated (P = .15) or RT dose (P = .56). The number of apheresis procedures performed was not associated with %BM treated (P = .54) or RT dose (P = .85). The amount of PBPCs collected did not differ significantly between patients receiving RT to the pelvis/sacrum (P = .20) and those receiving RT to the spine (P = .13). The time to platelet engraftment was longer for patients with higher %BM treated (P = .02). Eleven patients did not undergo a confirmed ASCT, owing to patient preference (3 patients), trial therapy (1 patient), comorbidities (1 patient), election for hospice (1 patient), inadequate collection (4 patients), or inadequate follow-up (1 patient). In our study cohort, RT prior to ASCT did not impair successful ASCT. RT must be carefully planned and delivered to ensure safe incorporation into pre-ASCT treatment regimens.

The Safety and Efficacy of Radiation Therapy with Concurrent Dexamethasone, Cyclophosphamide, Etoposide, and Cisplatin-Based Systemic Therapy for Multiple Myeloma

INTRODUCTION

The concurrent delivery of radiation therapy (RT) with salvage chemotherapies in the management of relapsed and refractory multiple myeloma (MM) is an area of ongoing investigation. This study examined the safety and efficacy of palliative RT given in the setting of concurrent dexamethasone, cyclophosphamide, etoposide, and cisplatin (DCEP).

PATIENTS AND METHODS

Fifty-five patients with MM received RT to 64 different sites within three weeks of receiving DCEP from 2010 to 2020. A median dose of 20 Gray (range 8-32.5 Gy) was delivered in a median of 5 fractions (range 1-15). Patients received a median of 1 cycle (range 1-5) of DCEP. Rates of hematologic and RT toxicity were recorded along with pain, radiographic, and laboratory responses to treatment.

RESULTS

RT was completed in 98% of patients. 21% of patients experienced RTOG grade 3+ hematologic toxicity before RT, which increased to 35% one-month post-RT (P = .13) before decreasing to 12% at 3 to 6 months (P = .02). The most common toxicity experienced was thrombocytopenia. Grade 1 to 2 non-hematologic RT-related toxicity was reported in 15% of patients while on treatment and fell to 6% one-month after completing RT. Pain resolved in 94% of patients with symptomatic lesions at baseline. Stable disease or better was observed in 34/39 (87%) of the targeted lesions on surveillance imaging.

CONCLUSION

RT administered concurrently with DCEP was well-tolerated by most of the patients in this series, with low rates of hematologic and RT-related toxicity. RT was also very effective, with the vast majority of patients demonstrating resolution of their pain and a significant response on follow-up imaging.

Does a Custom Electronic Health Record Alert System Improve Physician Compliance With National Quality Measures for Palliative Bone Metastasis Radiotherapy?

PURPOSE

In an effort to promote cost-conscious, high-quality, and patient-centered care in the palliative radiation of painful bone metastases, the National Quality Forum (NQF) formed measure 1822 in 2012, which recommends the use of one of the four dose-fractionation schemes (30 Gy in 10 fractions, 24 Gy in 6 fractions, 20 Gy in 5 fractions, or 8 Gy in a single fraction). We investigated whether a custom electronic health record (EHR) alert system improved quality measure compliance among 88 physicians at a large academic center and institutional network.

METHODS

In March 2018, a multiphase alert system was embedded in a custom web-based EHR. Prior to a course of palliative bone radiation, the alert system notified the user of NQF 1822 recommendations and, once prescription was completed, either affirmed compliance or advised a change in treatment schedule. Rates of compliance were evaluated before and after implementation of alert system.

RESULTS

Of 2,399 treatment courses, 86.5% were compliant with NQF 1822 recommendations. There was no difference in rates of NQF 1822 compliance before or after implementation of the custom EHR alert (86.0% before March 2018 v 86.9% during and after March 2018, P = .551).

CONCLUSION

There was no change in rates of compliance following implementation of a custom EHR alert system designed to make treatment recommendations based on national quality measure guidelines. To be of most benefit, future palliative bone metastasis decision aids should leverage peer review, target a clear practice deficiency, center upon high-quality practice guidelines, and allow flexibility to reflect the diversity of clinical scenarios.

Racial disparities in the use of palliative radiotherapy for black patients with multiple myeloma in the United States

Multiple myeloma (MM) is characterized by painful lesions that are amenable to palliative radiotherapy (PRT) but racial disparities may exist. In the current study, the National Cancer Database was queried for patients diagnosed with MM from 2004 to 2016 who received PRT. The percentages of patients receiving PRT within 12 months of diagnosis by race/ethnicity were: 15.5% non-Hispanic white (NHW), 14.3% African American (AA), 15.8% Hispanic, and 14.4% other. On multivariable logistic regression, the odds of receiving RT were 13% less for AAs compared to NHWs (OR = 0.87, 95% CI = 0.83-0.90, p < .0001) and the odds of dying within 30 days of PRT were 18% less for AAs compared to NHWs (OR = 0.82, 95% CI = 0.67-1.00, p = .046). This study highlights a health disparity affecting AA patients who despite having a higher incidence and mortality from MM are also less likely to receive PRT within 1 year of diagnosis and near the end of life.

Effective Pain Control With Very Low Dose Palliative Radiation Therapy for Patients With Multiple Myeloma With Uncomplicated Osseous Lesions

BACKGROUND

Osteolytic lesions are present in 75% of patients with multiple myeloma (MM) and frequently require palliation with radiation therapy (RT). Prior case series of patients with MM with bone pain undergoing palliative RT suggests doses ≥12 Gy (equivalent dose in 2Gy fractions, EQD2) provide excellent bone pain relief. However, recent advances in care and novel biologic agents have significantly improved overall survival and quality of life for patients with MM. We hypothesized that lower-dose RT (LDRT, EQD2 <12 Gy) offers an effective alternative to higher-dose RT (HDRT, EQD2 ≥12 Gy) for palliation of painful, uncomplicated MM bone lesions.

METHODS

We retrospectively identified patients with MM treated with RT for uncomplicated, painful bone lesions and stratified by EQD2 ≥/< 12 Gy. Clinical pain response (CPR) rates, acute and late toxicity, pain response duration, and retreatment rates between LDRT and HDRT groups were analyzed.

RESULTS

Thirty-five patients with 70 treated lesions were included: 24 patients (48 lesions) treated with HDRT and 11 patients (22 lesions) with LDRT. Median follow-up was 14 and 16.89 months for HDRT and LDRT, respectively. The median dose of HDRT treatment was 20 Gy versus 4 Gy in the LDRT group. The CPR rate was 98% for HDRT and 95% for LDRT. There was no significant difference in any-grade acute toxicity between the HDRT and LDRT cohorts (24.5% vs 9.1%, Χ² P = .20). Pain recurred in 10% of lesions (12% HDRT vs 9.5% LDRT). Median duration of pain response did not significantly differ between cohorts (P = .91). Five lesions were retreated, 2 (9.5%) in the LDRT cohort, and 3 (6.3%) in the HDRT cohort.

CONCLUSION

In this study, LDRT effectively palliated painful, uncomplicated MM bony lesions with acceptable CPR and duration of palliation. These data support prospective comparisons of LDRT versus HDRT for palliation of painful, uncomplicated MM bony lesions.

Clinical outcomes and complications of surgical interventions for multiple myeloma lesions in the extremities and pelvis: A retrospective clinical study

OBJECTIVE

This study aimed to assess the pain and functional status of patients who underwent various surgical interventions for the stabilization of selected multiple myeloma (MM) lesions in the extremities and pelvis and to investigate the rate of complications requiring reintervention.

METHODS

Patients with MM who underwent various surgical interventions for the extremity or pelvic lesions were retrospectively reviewed. Change in the pain intensity was assessed using visual analogous scale (VAS) preoperatively, at the time of discharge, and at the final follow-up. Functional status was assessed using the musculoskeletal tumor society (MSTS) scoring system for both upper and lower extremities preoperatively and at the final follow-up. Postoperative complications requiring reintervention, including dislocation, loss of fixation/aseptic loosening of prosthesis, mechanical insufficiency, periprosthetic fracture, infection, or progression of the local disease, were recorded.

RESULTS

A total of 49 (20 men and 29 women) previously (23) or newly (26) diagnosed patients with a mean age of 60.8±18.2 years were included in this study. Of these, 6 patients underwent multiple surgeries for different skeletal sites; in total, 57 procedures were performed. The mean follow-up was 47.7±21.63 months. The lesions were localized to the humerus (19), radius (1), pelvis (4), femur (30), and tibia (3). The surgical indications included therapy-refractory pain for 17 patients and pathological fractures due to progression of pre-existing lesions for 12 patients or newly diagnosed lesions with extensive bone destruction at initial presentation for 28 patients. Surgical procedures included prosthetic reconstruction in 32 patients, cement-augmented osteosynthesis in 9, and closed intramedullary nailing in 16. The mean VAS score decreased from 8.75±1.2 preoperatively to 3.21±1.56 at the time of discharge and 1.2±0.42 at the final follow-up. Although a significant decrease was detected between the preoperative and postoperative VAS scores at the time of discharge (p=0.0001), the decrease between the time of discharge and the final follow-up was statistically insignificant (p=0.086). The mean MSTS score significantly improved from 9.1%±6.4% (range: 0%-40%) preoperatively to 76%±14.9% (range: 40%-93.3%) at the final follow-up (p=0.0001). Significantly higher MSTS scores were obtained in the upper extremity than lower extremity/pelvis (p=0.04) and in isolated diaphyseal involvement than metaphyseal or articular involvement (p=0.032). A total of 11 complications requiring reintervention (19.2%) were observed, which included dislocation (3.5%), loss of fixation (5.2%), mechanical insufficiency (3.5%), infection (5.2%), and local tumor progression (1.7%). The rate of complications requiring reintervention was lower but statistically insignificant in the upper extremity (5%; 1/20) than lower extremity/pelvis (27%; 10/37) (p=0.076) and in isolated diaphyseal involvement (6.2%; 1/16) than metaphyseal or articular involvement (24.3%; 10/41) (p=0.079).

CONCLUSION

Although different types of surgeries can achieve pain relief and good function in different anatomical localizations, better functional results with lower complication rates may be obtained following surgical management of MM lesions in the upper extremities and in diaphyseal localizations.

LEVEL OF EVIDENCE

Level IV, Therapeutic Study.

Local Radiation Therapy for Palliation in Patients With Multiple Myeloma of the Spine

Purpose: The objective of this study was to assess a contemporary cohort of patients with multiple myeloma referred for palliative radiation to the mobile spine for clinical and radiological responses.

Materials/Methods: The records of patients treated between 2009 and 2016 with radiotherapy for multiple myeloma of the spine were retrospectively reviewed. Demographics, systemic therapy, radiation dose, number of fractions, radiographic response based upon adapted RECIST criteria, and symptomatic response were recorded.

Results: Eighty eight patients and 98 treatment courses were analyzed. All courses were analyzed for symptomatic response and 61 of the treatment courses were available for radiologic follow-up. The median follow-up was 9.7 months with a median radiation dose of 25 Gy (12.5–50 Gy) delivered in a median of 10 fractions (5–25 fractions). Fifty-four percent of patients had a high-risk lesion. Symptomatic response as measured by a decrease of ≤5 points on the pain related scale was 83% and 34% of patients had a decrease of >5 points. Of 35% of patients that had neurologic impairments prior to treatment, improvement was identified 83% of the time. Radiographic response was noted as 13% complete response, 16% partial response, 57% stable disease, and 13% disease progression. Specifically, high-risk lesions treated with radiation alone demonstrated no regression with only 10% demonstrating partial response.

Conclusion: This retrospective series of patients treated with palliative intent for multiple myeloma using various dose and fractionation schemes showed favorable symptomatic relief in most patients. Radiographic response did not correlate with clinical response with fewer patients having radiologic disease regression. Longer follow-up is necessary to determine if the lack of radiologic response is associated with clinically relevant recurrent pain.

Dose Selection for Multiple Myeloma in Modern Era

PURPOSE

The management of multiple myeloma (MM) has evolved over the past 20 years, secondary to novel biologic therapeutics. Radiation therapy remains an important intervention in the management of painful lytic bone lesions. However, the currently used radiation therapy regimens were developed in the pre-biologic therapy era. The goal of this study is to assess the effects of dose and fractionation in pain control for patients with MM in the modern era.

METHODS AND MATERIALS

We conducted a retrospective study based on data collected from patients who received radiation therapy at our institute between 2007 and 2017. A total of 130 patients (266 treatment sites) were included in this study. Univariate Cox proportional hazards models were used to analyze the association of risk of pain recurrence with treatment characteristics and compute the hazard ratios (HRs).

RESULTS

The median follow-up time was 14 months. Patients who received a total dose of 20 to <30 Gy (including 20 Gy) had a significantly lower probability of pain recurrence when compared with those who received <20 Gy (HR, 0.36; 95% confidence interval, 0.14-0.94; P = .0365). There was no statistically significant difference in treatment response or pain recurrence between the different fraction numbers and sizes. However, we noted a trend indicating lower pain recurrence in the group that received 6 to 10 fractions of radiation therapy (P = .06). Among the most commonly used regimens, 8 Gy in a single fraction resulted in a statistically significant increased chance of pain recurrence compared with 20 Gy in 10 fractions and a borderline statistically significant increased chance of pain recurrence when compared with 30 Gy in 10 fractions.

CONCLUSIONS

Radiation therapy remains highly effective at managing lytic bone lesions in patients with MM, and 6- to 10-fraction treatment courses are equally as effective as longer courses at treating these lesions. Treatment with 20 Gy in 10 fractions resulted in a significantly lower probability of pain recurrence when compared with 8 Gy in 1 fraction.

Incidence of spinal disease and role of spinal radiotherapy in multiple myeloma

Background

Spinal disease (spd) in multiple myeloma (mm) can be a major source of morbidity in newly diagnosed patients and long-term survivors. We retrospectively assessed the incidence of spinal disease in patients newly diagnosed with myeloma, its effect on survival, and the possible effect of spinal radiation therapy (rt).

Methods

Patients diagnosed with mm between 2010 and 2014 were identified through the provincial cancer registry. Plain radiography, computed tomography, and magnetic resonance imaging were reviewed to detect and document the type of spd. Data related to rt and systemic therapy were collected. Kaplan-Meier and time-varying Cox regression models were used to describe overall survival.

Results

Of 306 identified patients with newly diagnosed mm, 51% had spd, including 17% with lytic disease, 68% with compression fractures, and 15% with spinal cord compression. Of the patients with spd, 61% received spinal rt. Of those patients, 84% received spinal rt within 3 months after their diagnosis. Median dose was 20 Gy. Most patients (89.2%) received chemotherapy, and 22.5% underwent autologous stem-cell transplantation. Only 6 of the patients treated with spinal rt received re-irradiation to the same site. Overall survival was similar for patients with and without spd. On multivariate analysis, spinal rt had no effect on survival.

Conclusions

In patients newly diagnosed with mm, spd is a common presentation. With current systemic therapy, the presence of spd had no adverse effect on overall survival. The effect of spinal rt on overall survival was nonsignificant.

Balloon kyphoplasty and additional anterior odontoid screw fixation for treatment of unstable osteolytic lesions of the vertebral body C2: a case series

Background

Unstable osteolytic lesions of the occipitocervical junction are rare and may occur in hematological malignancy or vertebral hemangioma, among others. Different case reports have been published about vertebroplasty for treatment of spinal metastases of the upper cervical spine. Only few cases concern balloon kyphoplasty of C2. We present a consecutive case series including four patients with an osteolytic lesion of the dens axis and describe a technical note for balloon kyphoplasty of C2 and an additional anterior odontoid screw fixation.

Methods

Four consecutive patients with an osteolytic lesion of the vertebral body of C2 were treated by anterior balloon kyphoplasty and additional anterior odontoid screw fixation of the dens axis. The radiological imaging showed a lytic process of the vertebral body C2 with no vertebral collapse but involvement of more than 50% of the vertebral body in all patients.

Results

Two cases of potentially unstable osteolytic lesions of C2 by myeloma, one case with metastatic osteolytic lesion of C2 by adenocarcinoma of the colon and one patient with vertebral hemangioma located in C2 were presented to our clinic. In all cases, surgical treatment with an anterior balloon kyphoplasty of C2 and an additional anterior, bicortical odontoid screw placement was performed. Control x-rays showed sufficient osteosynthesis and cement placement in the vertebral body C2.

Discussion

Anterior balloon kyphoplasty and anterior odontoid screw placement is a safe treatment option for large osteolytic lesions of C2. The additional odontoid screw placement has the advantage of providing more stabilization and may prevent late complications, like odontoid fractures. For patients with potentially unstable or large osteolytic lesions of the dens without spinal cord compression or neurological symptoms we recommend the placement of an anterior odontoid screw when performing a balloon kyphoplasty. Level of evidence: - IV: retrospective or historical series.

Palliative external beam radiotherapy for the treatment of tumor bleeding in inoperable advanced gastric cancer

Background

To assess the outcomes and prognostic factors associated with palliative external beam radiotherapy (EBRT), administered to patients with advanced gastric cancer.

Methods

Forty-two patients with bleeding gastric tumors that received EBRT for palliation were analyzed. The response to EBRT was assessed by the palliation of tumor bleeding. Patients were classified as either responders, or non-responders to EBRT. The prognostic utility of clinical and dosimetric variables was examined in a multivariate logistic regression model. The optimal dose cutoff to classify the two groups was determined with receiver operating characteristic analysis.

Results

The palliation of gastric tumor bleeding after EBRT was achieved in 29 patients (69.0%). The time to resolve tumor bleeding ranged from 1 to 84 days (median, 15 days). The median duration of palliation was 14.9 weeks. The median EBRT dose was 40 Gy in responders vs. 21 Gy in non-responders, with the difference being significant (p < 0.001). The biologically effective dose (using α/β = 10, BED₁₀) for responders was significantly higher than the BED₁₀ for non-responders (median 48 Gy vs. 26.4 Gy, p < 0.001), and the optimal cut off value to separate the two groups was 36 Gy (p < 0.001). The absence of distant metastasis and the use of concurrent chemotherapy generally showed a better EBRT response (p = 0.079 and p = 0.079, respectively). In the multivariate analysis, BED₁₀ ≥ 36 Gy was the most significant factor associated with EBRT response (p = 0.001). Overall survival (OS) and re-bleeding-free survival was median 12.6 weeks and 14.9 weeks. The responders to EBRT showed superior OS (16.6 vs. 5.1 months, p < 0.001). Neither acute nor chronic toxicities of grade 3 or higher were observed.

Conclusions

EBRT is an effective method for treating tumor bleeding in advanced gastric cancer, and does not induce severe toxicity.