Jordan Wong1, Tom Pickles1, Joseph Connors2, Christina Aquino-Parsons1, Laurie Sehn2, Ciara Freeman1, Kim DeVries1, Andrea Lo3. 1. BC Cancer - Vancouver, University of British Columbia. 2. BC Cancer - Vancouver, University of British Columbia; BC Cancer - Vancouver, BC Cancer Center for Lymphoid Cancer, University of British Columbia. 3. BC Cancer - Vancouver, University of British Columbia. Electronic address: Andrea.Lo@bccancer.bc.ca.
Abstract
PURPOSE: The study objective was to investigate the effectiveness of palliative radiation therapy (RT) for patients with diffuse large B-cell lymphoma (DLBCL) and to identify factors, such as chemotherapy relapsed/refractory (R/R) disease, that may influence RT outcomes. METHODS AND MATERIALS: Patients with DLBCL who received palliative RT from 2001 to 2015 in British Columbia were reviewed for patient characteristics, treatment details, and outcomes. Univariable and multivariable analyses for response and local progression were performed. RESULTS: Three-hundred and seventy courses of palliative RT in 217 patients were identified. Median equivalent dose in 2 Gy fractions was 19 Gy (range, 2-42 Gy). Clinical and/or radiologic response occurred in 230 (83%) of the 276 courses with response data available. Local control following palliative RT at 6 months was 66.7%. On univariable analysis, R/R disease was not associated with lower clinical response rates but had higher risk of progression (hazard ratio [HR], 0.5; P = .040). On multivariable analyses, patients with R/R disease who did not require concurrent steroids had greater response compared with those who received upfront palliative RT (odds ratio, 3.5; P = .011). Response to first-line chemotherapy and smaller lesion size were associated with improved local progression rates (HR, 0.2; P < .001 and HR, 0.5; P = .020, respectively). RT dose fractionation factors were not significant on any analyses. CONCLUSIONS: Palliative RT for DLBCL is effective for symptom improvement, including in the chemotherapy R/R setting. Not requiring concurrent steroids, response to first-line chemotherapy, and smaller lesion size predicted better RT outcomes. There was no association between dose fractionation and response rates or local control to suggest that higher RT doses are more effective for palliation.
PURPOSE: The study objective was to investigate the effectiveness of palliative radiation therapy (RT) for patients with diffuse large B-cell lymphoma (DLBCL) and to identify factors, such as chemotherapy relapsed/refractory (R/R) disease, that may influence RT outcomes. METHODS AND MATERIALS: Patients with DLBCL who received palliative RT from 2001 to 2015 in British Columbia were reviewed for patient characteristics, treatment details, and outcomes. Univariable and multivariable analyses for response and local progression were performed. RESULTS: Three-hundred and seventy courses of palliative RT in 217 patients were identified. Median equivalent dose in 2 Gy fractions was 19 Gy (range, 2-42 Gy). Clinical and/or radiologic response occurred in 230 (83%) of the 276 courses with response data available. Local control following palliative RT at 6 months was 66.7%. On univariable analysis, R/R disease was not associated with lower clinical response rates but had higher risk of progression (hazard ratio [HR], 0.5; P = .040). On multivariable analyses, patients with R/R disease who did not require concurrent steroids had greater response compared with those who received upfront palliative RT (odds ratio, 3.5; P = .011). Response to first-line chemotherapy and smaller lesion size were associated with improved local progression rates (HR, 0.2; P < .001 and HR, 0.5; P = .020, respectively). RT dose fractionation factors were not significant on any analyses. CONCLUSIONS: Palliative RT for DLBCL is effective for symptom improvement, including in the chemotherapy R/R setting. Not requiring concurrent steroids, response to first-line chemotherapy, and smaller lesion size predicted better RT outcomes. There was no association between dose fractionation and response rates or local control to suggest that higher RT doses are more effective for palliation.