- Email: [email protected]
Radiation Therapy Fractionation Practice Patterns in End-of-Life Care
E508
International Journal of Radiation Oncology Biology Physics
were described using Kaplan-Meier methods with 95% confidence intervals. Results: There were 187 treatments delivered in 133 patients during the study period. The median age of patients was 65. The most common primary malignancies were prostate cancer (nZ34 patients), colorectal cancer (nZ25), lung cancer (nZ24) and bone and soft tissue sarcomas (nZ15). The two main target sites treated were lung (51%) and bone (41%). The common prescription doses were 26 Gy /1# (47%), 20 Gy /1# (34%) and 24 Gy/1# (10%). The freedom from local progression at 1 year was 90% (95% CI 84% - 95%) and 2 years 84% (95% CI 76% 92%). The freedom from distant progression was 52% at 1 year (95% CI 43% - 62%) and 39% at 2 years (95% CI 30% - 51%). The freedom from widespread disease was 74% at 1 year (95% CI 67% - 83%) and 60% at 2 years (95% CI 50% - 73%). The freedom from widespread disease after salvage SABR for further distant progression was 72% at 6 months (95% CI 60% - 88%) and 68% at 12 months (95% CI 54% 86%). The 1 year overall survival was 99% (95% CI 97% - 100%) and 2 year overall survival was 87% (95% CI 79% - 97%). No Grade 3 or higher treatment related toxicity was reported, with 94 patients (50.8%) not suffering any toxicity. Conclusion: Single fraction SABR is associated with a high rate of freedom from widespread disease, excellent local control, favorable overall survival, and low toxicity profile. Single fraction SABR is a resource efficient treatment that may delay the need for active systemic treatment in patients with oligometastatic disease. Author Disclosure: S. Gandhidasan: None. M. Bressel: None. T. Kron: None. M. Shaw: None. J. Chu: None. S. Chander: None. G. Wheeler: None. N. Plumridge: None. B. Chesson: None. A. Haworth: None. S.P. David: None. D. Ball: None. S. Siva: None.
Conclusion: ICU admission in patients with advanced cancer treated with palliative radiation therapy is associated with poor outcomes. Almost half of the patients with metastatic cancer in this study either died during the hospitalization or were discharged with hospice care, and few were able to receive any further cancer directed therapy after ICU admission. These results point to the palliative radiation consultation as an underutilized opportunity to address goals of care and advanced directives with patients and their families. Author Disclosure: S. Rakhra: None. R. Sacotte: None. F. Wehbe: None. J.M. Kruser: None. D. Liu: None. T. Kruser: None.
3247 Outcomes After Intensive Care Unit Admission for Patients Receiving Palliative Radiation Therapy: A Missed Opportunity for Goals of Care Discussions S. Rakhra,1 R. Sacotte,2 F. Wehbe,3 J.M. Kruser,4 D. Liu,5 and T. Kruser1; 1 Department of Radiation Oncology, The Robert H. Lurie Comprehensive Cancer Center, Chicago, IL, 2Feinberg School of Medicine, Northwestern University, Chicago, IL, 3Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 4 Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 5Northwestern University Cancer Biostatistics, Chicago, IL Purpose/Objective(s): Characterize outcomes of patients with advanced cancer treated with palliative radiation therapy who are subsequently admitted to an intensive care unit (ICU). Materials/Methods: We identified 271 patients at a single tertiary academic center with bone (62.7%) or brain (37.3%) metastases who were treated with palliative radiation therapy and subsequently admitted to an ICU between January 1, 2005, and December 31, 2015. The primary outcome measure was median survival after ICU admission. Secondary outcome measures included discharge disposition and receipt of additional cancer directed therapy following admission to ICU. Results: The patients were 51.3% female and the median age of ICU admission was 60 years (range 20 to 92 years). The most frequent sites of primary malignancy were lung (22.4%) and breast (19.0%). Patients received palliative radiation therapy to the following sites (including patients with more than one site of radiation): bone (55.0%), brain (41.0%), lung (5.9%), and other (5.5%). The median radiation dose was 30 Gy (range 3 to 60 Gy), and the median number of radiation fractions was 10 (range 1 to 30). After ICU admission, 42.4% of patients died during the hospitalization, 37.6% were discharged home, 12.5% of patients were discharged to a long-term care facility, 6.6% of patients were discharged to hospice, and 1.1% had other dispositions. Median survival from the date of ICU admission was 23 days. Most patients (82.0%) received no further cancer-directed therapy after ICU admission.
3248 Radiation Therapy Fractionation Practice Patterns in End-of-Life Care S. Aggarwal,1 N.D. Prionas,2 J.N. Carter,3 K.A. Kumar,1 P. Pradhan,3 J.L. Bui,3 R. von Eyben,3 A.C. Koong,1 and D.T. Chang4; 1Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, 2Stanford University Department of Radiation Oncology, Stanford, CA, 3Stanford University, Stanford, CA, 4Stanford University School of Medicine, Department of Radiation Oncology, Stanford, CA Purpose/Objective(s): Radiation therapy is commonly used for palliation for metastatic disease. However, during end-of-life care, optimizing the benefit of intervention with the cost of time and inconvenience receiving palliative therapy is important. The purpose of this study is to evaluate the patterns of use of various fractionation schemes used for palliation of patients with metastatic disease. Materials/Methods: We prospectively enrolled 242 patients with metastatic disease who were treated with palliative external beam radiation therapy (EBRT) at our institution from March through December 2015. In total, 69 patients died and were eligible for evaluation. Fractionation was binned as <5 (short), 5-9 (intermediate), or 10 (long) fractions. Common fractionation schedules used were 8 Gy in 1 fraction (83%) for the short group, 20 Gy in 5 fractions (89%) in the intermediate group, and 30 Gy in 10 fractions (62%) in the long group. For 7 patients (10%), palliative radiation was delivered to a previously irradiated site, 0 (0%), 3 (43%), and 4 (57%) of whom received short, intermediate, and long fractionations, respectively. Results: The median follow-up was 3.4 months. Of the 69 deceased patients, 12 (17%), 18 (26%), and 39 (57%) were prescribed short, intermediate, and long fractionation schemes, respectively. For patients that died within 3 months of radiation, 23%, 30%, and 46% received short, intermediate, and long fractionation, respectively. For patients that died 4-6 months after receiving radiation, 6%, 16%, and 78% received each scheme. For patients that died >6 months after receiving radiation, 0%, 20%, and 80% were prescribed each fractionation scheme. The difference in schedule for these patients was statistically significant (P < 0.001). For the 62 patients who died >6 months from receiving radiation or are living with >6 months of follow-up, 4 (7%), 15 (25%), and 43 (68%) were prescribed short, intermediate, and long fractionation schemes, respectively. For patients who died within 6 months of treatment, those who received short radiotherapy were treated on 3% of their remaining days alive, those who received intermediate radiotherapy were treated on 19% of their remaining days alive, and those who received long radiotherapy were treated on 23% of their remaining days alive. Seven patients (2.9%) required subsequent re-irradiation to the same site since this study started. Conclusion: While patients who lived a shorter amount of time after palliative EBRT were more likely to be prescribed a shorter fractionation scheme, the time spent at end-of-life undergoing radiotherapy suggests that short fractionation schemes should be integrated more into clinical practice to reduce the burden of treatment on these patients. Improved understanding of prognosis and better selection of treatment schedule is needed to optimize the utilization of palliative radiation.
Volume 96 Number 2S Supplement 2016 Author Disclosure: S. Aggarwal: None. N.D. Prionas: None. J.N. Carter: None. K.A. Kumar: None. P. Pradhan: None. J.L. Bui: None. R. von Eyben: None. A.C. Koong: None. D.T. Chang: None.
3249 Impact of Baseline Cachexia in Non-Small Cell Lung Cancer on Radiation Therapy Utilization and Survival F. Giap,1 S.K.M. Lau,1 B.S. Gannavaparu,1 and P. Iyengar2; 1University of Texas Southwestern, Dallas, TX, 2University of Texas Southwestern Medical Center, Dallas, TX Purpose/Objective(s): Cancer cachexia is a well-described syndrome of progressive functional impairment characterized by unintentional weight loss. However, the presence of cachexia at the time of cancer diagnosis and its influence on disease management and treatment outcomes for patients receiving radiotherapy are poorly described. Here, we assess the role of cachexia at baseline in patients with NSCLC on first-line treatment modality and clinical outcomes. Materials/Methods: Retrospective review of medical records identified 1,334 patients with NSCLC consecutively treated at a tertiary care health system between 1/1/06 and 12/31/13. Cachexia was defined using the wellaccepted and validated international consensus definition. The delivery of radiotherapy and its treatment intent, whether curative or palliative, were abstracted. Results: The cohort included a representative group of patients with a median age at diagnosis of 64 years, 623 (46.7%) females, and 422 (31.6%) patients of non-White race. Stage at diagnosis was 0, I, II, III, and IV, in 4 (0.3%), 291 (21.8%), 105 (7.9%), 356 (26.7%), and 578 (43.3%) patients, respectively. Cachexia was present at the time of diagnosis in 403 (30.2%) patients including 17.5%, 14.3%, and 32.0% of stage I, II, and III patients, respectively. Curative intent radiotherapy was prescribed to 48.4% and 45.8% of stage I+II patients with and without cachexia, respectively (PZ.69). Curative intent radiation was administered to 75.4% and 76.0% of stage III patients with and without cachexia, respectively (PZ.98). Palliative intent radiation therapy (RT) was received by significantly more stage IV patients with cachexia (74.4%) than without cachexia (63.4%) (X2, PZ.006). 857 deaths have been observed, with a median follow-up of 23.7 months for patients alive at the time of analysis. Cachexia at the time of diagnosis was prognostic for worse survival by stage. For patients with stage I NSCLC, median survival was 67.1 months for patients without cachexia but 45.0 months with cachexia at diagnosis (PZ.033). For stage I patients receiving curative intent RT, median survival was 39.9 and 25.2 months for patients without and with cachexia, respectively (PZ.31). Cachexia remained significant in stage III NSCLC, with median survival of 20.5 and 13.8 months with or without cachexia at diagnosis, respectively (PZ.013). For stage III patients receiving curative intent RT, median survival was 23.9 and 15.0 months for patients without and with cachexia, respectively (PZ.009). Conclusion: Cancer cachexia at the time of diagnosis is common in patients with NSCLC even with early stage disease. The presence of cachexia at diagnosis does not appear to influence the utilization of RT as a curative modality. However, cachexia at diagnosis of NSCLC, even with early stage disease, is prognostic of worse outcomes despite curative intent therapy. Further studies on the biologic mechanisms and treatment of cancer cachexia may provide novel therapeutic avenues. Author Disclosure: F. Giap: None. S.K. Lau: None. B.S. Gannavaparu: None. P. Iyengar: None.
Poster Viewing E509
3250 Significance of Hormone Therapy and Bisphosphonate Use on Vertebral Compression Fracture (VCF) Incidence Following Spine Stereotactic Body Radiation Therapy (SBRT) for Breast Cancer Metastases E. Elibe, D. Boyce-Fappiano, E.M. Walker, I.Y. Lee, J. Rock, S. Siddiqui, and F. Siddiqui; Henry Ford Health System, Detroit, MI Purpose/Objective(s): Spinal metastases are increasingly being treated with SBRT. Though effective, a potential toxicity of SBRT is VCF. Breast cancer (BC) is one of the most common primary sites to metastasize to the spine, and due to factors such as hormone therapy (HT) use, these patients may be at higher risk for VCF following SBRT. Our study aimed to determine the rate of SBRT induced VCF (S-VCF) in BC patients, and to understand if there is a significant relationship between HT and bisphosphonate (Bp) use on this risk. Materials/Methods: 335 vertebral bodies (VB) (nZ131 patients) were treated with spine SBRT for BC metastases at a single institution between June 2001 and December 2014. EMRs were retrospectively reviewed in this IRB approved study, and data on the use of Bp, selective estrogen receptor modulators (SERMs), and aromatase inhibitors (AIs) were recorded. Development of a new VCF, progression of an existing VCF and requirement of stabilization surgery after SBRT were the primary endpoints of this study. These were evaluated using computed tomography and magnetic resonance images. Only VCF development/progression occurring in VBs treated with SBRT were considered. VBs with concurrent tumor progression, or stabilization surgery prior to SBRT were not included. Statistical significance of SVCF, and the use of Bp and HT concurrent to, within 6 months, 1 year, and 2 years of SBRT, was evaluated using the Chi-Square Test for Independence, and Fisher’s Exact Test. Results: Follow up was available for 91 patients (69%) & 233 VBs. Median survival post SBRT was 21 m. 58.8% of patients were white, 33.6% African American, and 7.6% were of other ethnicities. Bone density was low in 59% of patients. Median SBRT dose was 18 Gy/1 fx. Median tumor volume was 35.83 cc. Median follow-up was 15.6 m. 33 VCFs in 20 patients were observed. 16 (48%) were new VCFs, 8 (24%) progressed, & 9 (27%) were VBs that required surgical stabilization after SBRT. The overall S-VCF rate was 14%. Of the patients evaluable for follow-up, 70 patients (192 VBs) 50 patients (146 VBs), & 78 patients (221 VBs) were exposed to AIs, SERMs, and Bp, with S-VCF rates of 14.6%, 14%, and 13% respectively. The following were found to be statistically significant in relation to VCF rate: SERM use concurrent to (PZ0.003), within 6 m of (PZ0.028), and within 2 yrs of (PZ0.021) SBRT. Also significant was Bp use within 1 yr of SBRT (P< 0.0001). AI use was not found to be statistically significant for any of the time frames evaluated in our study. Conclusion: Rate of developing an S-VCF in our cohort was 14%. The overall rate of S-VCF in BC patients is not considerably higher than S-VCF rates previously reported in non-histology specific series. We will further analyze our cohort to better understand the protective or adverse effects of HT and Bp use in BC patients receiving spine SBRT. To the best of our knowledge, this is the only reported series analyzing S-VCFs in BC with an emphasis on the relation of Bp and HT use. Author Disclosure: E. Elibe: None. D. Boyce-Fappiano: None. E.M. Walker: None. I.Y. Lee: Honoraria; Varian Medical Systems. Consultant; Medtronic. Travel Expenses; Varian Medical Systems. J. Rock: None. S. Siddiqui: Research Grant; Varian Medical Systems, Inc., Phillips Medical. Directs QA program; Henry Ford Hospital. F. Siddiqui: Research Grant; Varian Medical Systems, Inc., Phillips Medical. Oversees the department; Henry Ford Hospital.
International Journal of Radiation Oncology Biology Physics
were described using Kaplan-Meier methods with 95% confidence intervals. Results: There were 187 treatments delivered in 133 patients during the study period. The median age of patients was 65. The most common primary malignancies were prostate cancer (nZ34 patients), colorectal cancer (nZ25), lung cancer (nZ24) and bone and soft tissue sarcomas (nZ15). The two main target sites treated were lung (51%) and bone (41%). The common prescription doses were 26 Gy /1# (47%), 20 Gy /1# (34%) and 24 Gy/1# (10%). The freedom from local progression at 1 year was 90% (95% CI 84% - 95%) and 2 years 84% (95% CI 76% 92%). The freedom from distant progression was 52% at 1 year (95% CI 43% - 62%) and 39% at 2 years (95% CI 30% - 51%). The freedom from widespread disease was 74% at 1 year (95% CI 67% - 83%) and 60% at 2 years (95% CI 50% - 73%). The freedom from widespread disease after salvage SABR for further distant progression was 72% at 6 months (95% CI 60% - 88%) and 68% at 12 months (95% CI 54% 86%). The 1 year overall survival was 99% (95% CI 97% - 100%) and 2 year overall survival was 87% (95% CI 79% - 97%). No Grade 3 or higher treatment related toxicity was reported, with 94 patients (50.8%) not suffering any toxicity. Conclusion: Single fraction SABR is associated with a high rate of freedom from widespread disease, excellent local control, favorable overall survival, and low toxicity profile. Single fraction SABR is a resource efficient treatment that may delay the need for active systemic treatment in patients with oligometastatic disease. Author Disclosure: S. Gandhidasan: None. M. Bressel: None. T. Kron: None. M. Shaw: None. J. Chu: None. S. Chander: None. G. Wheeler: None. N. Plumridge: None. B. Chesson: None. A. Haworth: None. S.P. David: None. D. Ball: None. S. Siva: None.
Conclusion: ICU admission in patients with advanced cancer treated with palliative radiation therapy is associated with poor outcomes. Almost half of the patients with metastatic cancer in this study either died during the hospitalization or were discharged with hospice care, and few were able to receive any further cancer directed therapy after ICU admission. These results point to the palliative radiation consultation as an underutilized opportunity to address goals of care and advanced directives with patients and their families. Author Disclosure: S. Rakhra: None. R. Sacotte: None. F. Wehbe: None. J.M. Kruser: None. D. Liu: None. T. Kruser: None.
3247 Outcomes After Intensive Care Unit Admission for Patients Receiving Palliative Radiation Therapy: A Missed Opportunity for Goals of Care Discussions S. Rakhra,1 R. Sacotte,2 F. Wehbe,3 J.M. Kruser,4 D. Liu,5 and T. Kruser1; 1 Department of Radiation Oncology, The Robert H. Lurie Comprehensive Cancer Center, Chicago, IL, 2Feinberg School of Medicine, Northwestern University, Chicago, IL, 3Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 4 Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 5Northwestern University Cancer Biostatistics, Chicago, IL Purpose/Objective(s): Characterize outcomes of patients with advanced cancer treated with palliative radiation therapy who are subsequently admitted to an intensive care unit (ICU). Materials/Methods: We identified 271 patients at a single tertiary academic center with bone (62.7%) or brain (37.3%) metastases who were treated with palliative radiation therapy and subsequently admitted to an ICU between January 1, 2005, and December 31, 2015. The primary outcome measure was median survival after ICU admission. Secondary outcome measures included discharge disposition and receipt of additional cancer directed therapy following admission to ICU. Results: The patients were 51.3% female and the median age of ICU admission was 60 years (range 20 to 92 years). The most frequent sites of primary malignancy were lung (22.4%) and breast (19.0%). Patients received palliative radiation therapy to the following sites (including patients with more than one site of radiation): bone (55.0%), brain (41.0%), lung (5.9%), and other (5.5%). The median radiation dose was 30 Gy (range 3 to 60 Gy), and the median number of radiation fractions was 10 (range 1 to 30). After ICU admission, 42.4% of patients died during the hospitalization, 37.6% were discharged home, 12.5% of patients were discharged to a long-term care facility, 6.6% of patients were discharged to hospice, and 1.1% had other dispositions. Median survival from the date of ICU admission was 23 days. Most patients (82.0%) received no further cancer-directed therapy after ICU admission.
3248 Radiation Therapy Fractionation Practice Patterns in End-of-Life Care S. Aggarwal,1 N.D. Prionas,2 J.N. Carter,3 K.A. Kumar,1 P. Pradhan,3 J.L. Bui,3 R. von Eyben,3 A.C. Koong,1 and D.T. Chang4; 1Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, 2Stanford University Department of Radiation Oncology, Stanford, CA, 3Stanford University, Stanford, CA, 4Stanford University School of Medicine, Department of Radiation Oncology, Stanford, CA Purpose/Objective(s): Radiation therapy is commonly used for palliation for metastatic disease. However, during end-of-life care, optimizing the benefit of intervention with the cost of time and inconvenience receiving palliative therapy is important. The purpose of this study is to evaluate the patterns of use of various fractionation schemes used for palliation of patients with metastatic disease. Materials/Methods: We prospectively enrolled 242 patients with metastatic disease who were treated with palliative external beam radiation therapy (EBRT) at our institution from March through December 2015. In total, 69 patients died and were eligible for evaluation. Fractionation was binned as <5 (short), 5-9 (intermediate), or 10 (long) fractions. Common fractionation schedules used were 8 Gy in 1 fraction (83%) for the short group, 20 Gy in 5 fractions (89%) in the intermediate group, and 30 Gy in 10 fractions (62%) in the long group. For 7 patients (10%), palliative radiation was delivered to a previously irradiated site, 0 (0%), 3 (43%), and 4 (57%) of whom received short, intermediate, and long fractionations, respectively. Results: The median follow-up was 3.4 months. Of the 69 deceased patients, 12 (17%), 18 (26%), and 39 (57%) were prescribed short, intermediate, and long fractionation schemes, respectively. For patients that died within 3 months of radiation, 23%, 30%, and 46% received short, intermediate, and long fractionation, respectively. For patients that died 4-6 months after receiving radiation, 6%, 16%, and 78% received each scheme. For patients that died >6 months after receiving radiation, 0%, 20%, and 80% were prescribed each fractionation scheme. The difference in schedule for these patients was statistically significant (P < 0.001). For the 62 patients who died >6 months from receiving radiation or are living with >6 months of follow-up, 4 (7%), 15 (25%), and 43 (68%) were prescribed short, intermediate, and long fractionation schemes, respectively. For patients who died within 6 months of treatment, those who received short radiotherapy were treated on 3% of their remaining days alive, those who received intermediate radiotherapy were treated on 19% of their remaining days alive, and those who received long radiotherapy were treated on 23% of their remaining days alive. Seven patients (2.9%) required subsequent re-irradiation to the same site since this study started. Conclusion: While patients who lived a shorter amount of time after palliative EBRT were more likely to be prescribed a shorter fractionation scheme, the time spent at end-of-life undergoing radiotherapy suggests that short fractionation schemes should be integrated more into clinical practice to reduce the burden of treatment on these patients. Improved understanding of prognosis and better selection of treatment schedule is needed to optimize the utilization of palliative radiation.
Volume 96 Number 2S Supplement 2016 Author Disclosure: S. Aggarwal: None. N.D. Prionas: None. J.N. Carter: None. K.A. Kumar: None. P. Pradhan: None. J.L. Bui: None. R. von Eyben: None. A.C. Koong: None. D.T. Chang: None.
3249 Impact of Baseline Cachexia in Non-Small Cell Lung Cancer on Radiation Therapy Utilization and Survival F. Giap,1 S.K.M. Lau,1 B.S. Gannavaparu,1 and P. Iyengar2; 1University of Texas Southwestern, Dallas, TX, 2University of Texas Southwestern Medical Center, Dallas, TX Purpose/Objective(s): Cancer cachexia is a well-described syndrome of progressive functional impairment characterized by unintentional weight loss. However, the presence of cachexia at the time of cancer diagnosis and its influence on disease management and treatment outcomes for patients receiving radiotherapy are poorly described. Here, we assess the role of cachexia at baseline in patients with NSCLC on first-line treatment modality and clinical outcomes. Materials/Methods: Retrospective review of medical records identified 1,334 patients with NSCLC consecutively treated at a tertiary care health system between 1/1/06 and 12/31/13. Cachexia was defined using the wellaccepted and validated international consensus definition. The delivery of radiotherapy and its treatment intent, whether curative or palliative, were abstracted. Results: The cohort included a representative group of patients with a median age at diagnosis of 64 years, 623 (46.7%) females, and 422 (31.6%) patients of non-White race. Stage at diagnosis was 0, I, II, III, and IV, in 4 (0.3%), 291 (21.8%), 105 (7.9%), 356 (26.7%), and 578 (43.3%) patients, respectively. Cachexia was present at the time of diagnosis in 403 (30.2%) patients including 17.5%, 14.3%, and 32.0% of stage I, II, and III patients, respectively. Curative intent radiotherapy was prescribed to 48.4% and 45.8% of stage I+II patients with and without cachexia, respectively (PZ.69). Curative intent radiation was administered to 75.4% and 76.0% of stage III patients with and without cachexia, respectively (PZ.98). Palliative intent radiation therapy (RT) was received by significantly more stage IV patients with cachexia (74.4%) than without cachexia (63.4%) (X2, PZ.006). 857 deaths have been observed, with a median follow-up of 23.7 months for patients alive at the time of analysis. Cachexia at the time of diagnosis was prognostic for worse survival by stage. For patients with stage I NSCLC, median survival was 67.1 months for patients without cachexia but 45.0 months with cachexia at diagnosis (PZ.033). For stage I patients receiving curative intent RT, median survival was 39.9 and 25.2 months for patients without and with cachexia, respectively (PZ.31). Cachexia remained significant in stage III NSCLC, with median survival of 20.5 and 13.8 months with or without cachexia at diagnosis, respectively (PZ.013). For stage III patients receiving curative intent RT, median survival was 23.9 and 15.0 months for patients without and with cachexia, respectively (PZ.009). Conclusion: Cancer cachexia at the time of diagnosis is common in patients with NSCLC even with early stage disease. The presence of cachexia at diagnosis does not appear to influence the utilization of RT as a curative modality. However, cachexia at diagnosis of NSCLC, even with early stage disease, is prognostic of worse outcomes despite curative intent therapy. Further studies on the biologic mechanisms and treatment of cancer cachexia may provide novel therapeutic avenues. Author Disclosure: F. Giap: None. S.K. Lau: None. B.S. Gannavaparu: None. P. Iyengar: None.
Poster Viewing E509
3250 Significance of Hormone Therapy and Bisphosphonate Use on Vertebral Compression Fracture (VCF) Incidence Following Spine Stereotactic Body Radiation Therapy (SBRT) for Breast Cancer Metastases E. Elibe, D. Boyce-Fappiano, E.M. Walker, I.Y. Lee, J. Rock, S. Siddiqui, and F. Siddiqui; Henry Ford Health System, Detroit, MI Purpose/Objective(s): Spinal metastases are increasingly being treated with SBRT. Though effective, a potential toxicity of SBRT is VCF. Breast cancer (BC) is one of the most common primary sites to metastasize to the spine, and due to factors such as hormone therapy (HT) use, these patients may be at higher risk for VCF following SBRT. Our study aimed to determine the rate of SBRT induced VCF (S-VCF) in BC patients, and to understand if there is a significant relationship between HT and bisphosphonate (Bp) use on this risk. Materials/Methods: 335 vertebral bodies (VB) (nZ131 patients) were treated with spine SBRT for BC metastases at a single institution between June 2001 and December 2014. EMRs were retrospectively reviewed in this IRB approved study, and data on the use of Bp, selective estrogen receptor modulators (SERMs), and aromatase inhibitors (AIs) were recorded. Development of a new VCF, progression of an existing VCF and requirement of stabilization surgery after SBRT were the primary endpoints of this study. These were evaluated using computed tomography and magnetic resonance images. Only VCF development/progression occurring in VBs treated with SBRT were considered. VBs with concurrent tumor progression, or stabilization surgery prior to SBRT were not included. Statistical significance of SVCF, and the use of Bp and HT concurrent to, within 6 months, 1 year, and 2 years of SBRT, was evaluated using the Chi-Square Test for Independence, and Fisher’s Exact Test. Results: Follow up was available for 91 patients (69%) & 233 VBs. Median survival post SBRT was 21 m. 58.8% of patients were white, 33.6% African American, and 7.6% were of other ethnicities. Bone density was low in 59% of patients. Median SBRT dose was 18 Gy/1 fx. Median tumor volume was 35.83 cc. Median follow-up was 15.6 m. 33 VCFs in 20 patients were observed. 16 (48%) were new VCFs, 8 (24%) progressed, & 9 (27%) were VBs that required surgical stabilization after SBRT. The overall S-VCF rate was 14%. Of the patients evaluable for follow-up, 70 patients (192 VBs) 50 patients (146 VBs), & 78 patients (221 VBs) were exposed to AIs, SERMs, and Bp, with S-VCF rates of 14.6%, 14%, and 13% respectively. The following were found to be statistically significant in relation to VCF rate: SERM use concurrent to (PZ0.003), within 6 m of (PZ0.028), and within 2 yrs of (PZ0.021) SBRT. Also significant was Bp use within 1 yr of SBRT (P< 0.0001). AI use was not found to be statistically significant for any of the time frames evaluated in our study. Conclusion: Rate of developing an S-VCF in our cohort was 14%. The overall rate of S-VCF in BC patients is not considerably higher than S-VCF rates previously reported in non-histology specific series. We will further analyze our cohort to better understand the protective or adverse effects of HT and Bp use in BC patients receiving spine SBRT. To the best of our knowledge, this is the only reported series analyzing S-VCFs in BC with an emphasis on the relation of Bp and HT use. Author Disclosure: E. Elibe: None. D. Boyce-Fappiano: None. E.M. Walker: None. I.Y. Lee: Honoraria; Varian Medical Systems. Consultant; Medtronic. Travel Expenses; Varian Medical Systems. J. Rock: None. S. Siddiqui: Research Grant; Varian Medical Systems, Inc., Phillips Medical. Directs QA program; Henry Ford Hospital. F. Siddiqui: Research Grant; Varian Medical Systems, Inc., Phillips Medical. Oversees the department; Henry Ford Hospital.