English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Plasmacytomas are local tumor deposits of multiple myeloma (MM) that can cause focal symptoms including nerve compression, pain, and fracture. Although systemic therapy is the primary treatment for MM, focal radiation therapy (RT) can provide effective palliation of symptomatic plasmacytomas.However, RT can also cause irreversible bone marrow fibrosis and myelosuppression, particularly at doses greater than 30 Gy. Adequate bone marrow reserve is essential for receipt of systemic therapy and stem cell transplantation. Focal RT must be used in a way that is mindful of the overall dose to the bone marrow. The optimal RT dose and fractionation for MM is not clearly established, as existing data were collected from small numbers of patients and the ranges of doses used were limited. Hematologic tumors are radiosensitive and lower doses are expected to produce effective palliation. Several studies have shown palliation from RT doses as low as 8–15 Gy. However, for patients with spinal myeloma causing cord compression, hypofractionated treatments have been found to be inferior for maintaining or restoring ambulation. Existing data are conflicting regarding the optimal radiation dose but suggest that dose escalation is warranted in some situations. Over the last decade, our practice has been to reduce the dose for palliation of MM. The radiation fields that we use in our practice have evolved to become more aligned with “involved site radiation therapy” as defined by the International Lymphoma Radiation Oncology Group (ILROG).We undertook this study to understand palliative radiation treatment patterns in a large cohort of patients with MM and to investigate the relationship between radiation dose and local disease control. We identified all patients aged ≥18 years with a diagnosis of MM who were treated with RT from 1999 through 2017. Charts were reviewed for age, site of disease, radiation dose, and number of radiation fractions. The biologically effective dose (BED) was calculated assuming an α/b of 10 for tumors. A treatment site was defined as a site encompassed by a single radiation field. Reirradiation was defined as treatment at a later date with an overlap of the prescription dose of the new treatment with the prescription dose of the prior treatment. Among patients who received spinal RT, we identified those treatments for which magnetic resonance imaging (or positron emission tomography/computed tomography) of the target lesion had been performed no more than 60 days before RT and at any point after RT. Maximum standard uptake values, Bilsky score, and paraspinal extent were measured. Local failure was defined as any evidence of radiographic progression within the radiation field on images obtained after treatment. All statistical analyses were done with SPSS (version 22.0, Armonk, NY, USA). Disease-related outcomes were evaluated using the Kaplan-Meier method. Cox proportional hazards testing was used for univariate analyses while multivariable Cox proportional hazards regression models were generated to analyze the effects of multiple variables of interest on disease-related outcomes. All tests were two-sided, with an α of 0.05 as the threshold for statistical significance. Patient and treatment characteristics are outlined in Table 1. A total of 772 patients given treatment to 1,513 sites were identified. The median follow-up time was 65.6 months after completion of RT. The most common ly treated site was the spine (39.4%, n=596); 55.9% of patients (n=431) were given treatment to a single site, 22.9% (175) were given treatment to two sites and 21.4% (n=166) were given treatment to three or more sites. The maximum number of treated sites in a single patient was 18. The most common dose and fractionation schemes were 2 Gy × 10 (n=413, 27.3%; BED=24 Gy10), 2 Gy × 12 (n=209, 13.8%; BED=28.8 Gy10), 2.5 Gy × 8 (n=135, 8.9%; BED=25 Gy10), and 2.5 Gy × 10 (n=277, 18.3%;, BED=31.25 Gy10). Only 46 sites (3%) were treated with 3 Gy x 10 (BED=39 Gy10). The median BED was 28.8 Gy10 (range, 7.5–60.0 Gy10). Most patients received a regimen involving five or more fractions (n=1,475, 98.5%). Of the 1,513 sites treated, 39 underwent reirradiation (2.6%). The most common reasons for reirradiation were

New paradigm for radiation in multiple myeloma: lower yet effective dose to avoid radiation toxicity