M.S. Jawad

Safety and efficacy of stereotactic body radiotherapy as primary treatment for vertebral metastases: a multi-institutional analysis

PurposeTo evaluate patient selection criteria, methodology, safety and clinical outcomes of stereotactic body radiotherapy (SBRT) for treatment of vertebral metastases.Materials and methodsEight centers from the United States (n = 5), Canada (n = 2) and Germany (n = 1) participated in the retrospective study and analyzed 301 patients with 387 vertebral metastases. No patient had been exposed to prior radiation at the treatment site. All patients were treated with linac-based SBRT using cone-beam CT image-guidance and online correction of set-up errors in six degrees of freedom.Results387 spinal metastases were treated and the median follow-up was 11.8 months. The median number of consecutive vertebrae treated in a single volume was one (range, 1-6), and the median total dose was 24 Gy (range 8-60 Gy) in 3 fractions (range 1-20). The median EQD210 was 38 Gy (range 12-81 Gy). Median overall survival (OS) was 19.5 months and local tumor control (LC) at two years was 83.9%. On multivariate analysis for OS, male sex (p < 0.001; HR = 0.44), performance status <90 (p < 0.001; HR = 0.46), presence of visceral metastases (p = 0.007; HR = 0.50), uncontrolled systemic disease (p = 0.007; HR = 0.45), >1 vertebra treated with SBRT (p = 0.04; HR = 0.62) were correlated with worse outcomes. For LC, an interval between primary diagnosis of cancer and SBRT of ≤30 months (p = 0.01; HR = 0.27) and histology of primary disease (NSCLC, renal cell cancer, melanoma, other) (p = 0.01; HR = 0.21) were correlated with worse LC. Vertebral compression fractures progressed and developed de novo in 4.1% and 3.6%, respectively. Other adverse events were rare and no radiation induced myelopathy reported.ConclusionsThis multi-institutional cohort study reports high rates of efficacy with spine SBRT. At this time the optimal fractionation within high dose practice is unknown.

Vertebral compression fractures after stereotactic body radiation therapy: a large, multi-institutional, multinational evaluation

OBJECTIVE The purpose of this study was to identify factors contributing to an increased risk for vertebral compression fracture (VCF) following stereotactic body radiation therapy (SBRT) for spinal tumors. METHODS A total of 594 tumors were treated with spinal SBRT as primary treatment or re-irradiation at 8 different institutions as part of a multi-institutional research consortium. Patients underwent LINAC-based, image-guided SBRT to a median dose of 20 Gy (range 8-40 Gy) in a median of 1 fraction (range 1-5 fractions). Median patient age was 62 years. Seventy-one percent of tumors were osteolytic, and a preexisting vertebral compression fracture (VCF) was present in 24% of cases. Toxicity was assessed following treatment. Univariate and multivariate analyses were performed using a logistic regression method to determine parameters predictive for post-SBRT VCF. RESULTS At a median follow-up of 10.1 months (range 0.03-57 months), 80% of patients had local tumor control. At the time of last imaging follow-up, at a median of 8.8 months after SBRT, 3% had a new VCF, and 2.7% had a progressive VCF. For development of any (new or progressive) VCF following SBRT, the following factors were predictive for VCF on univariate analysis: short interval from primary diagnosis to SBRT (less than 36.8 days), solitary metastasis, no additional bone metastases, no prior chemotherapy, preexisting VCF, no MRI used for target delineation, tumor volume of 37.3 cm(3) or larger, equivalent 2-Gy-dose (EQD2) tumor of 41.8 Gy or more, and EQD2 spinal cord Dmax of 46.1 Gy or more. Preexisting VCF, solitary metastasis, and prescription dose of 38.4 Gy or more were predictive on multivariate analysis. The following factors were predictive of a new VCF on univariate analysis: solitary metastasis, no additional bone metastases, and no MRI used for target delineation. Presence of a solitary metastasis and lack of MRI for target delineation remained significant on multivariate analysis. CONCLUSIONS A VCF following SBRT is more likely to occur following treatment for a solitary spinal metastasis, reflecting a more aggressive treatment approach in patients with adequately controlled systemic disease. Higher prescription dose and a preexisting VCF also put patients at increased risk for post-SBRT VCF. In these patients, pre-SBRT cement augmentation could be considered to decrease the risk of subsequent VCF.

Cost-effectiveness of 3-dimensional conformal radiotherapy and applicator-based brachytherapy in the delivery of accelerated partial breast irradiation.

Purpose:To compare reimbursement and cost efficacy between accelerated partial breast irradiation (APBI) techniques. Materials/Methods:Four hundred fifty-three patients were treated with APBI using either 3-dimensional conformal radiotherapy (3D-CRT, n=207) or balloon-based brachytherapy (BB) [single-lumen (SL, n=161) and multilumen (ML, n=85)] between March 2000 and October 2011. To evaluate cost-effectiveness, reimbursement by treatment technique was calculated based on 2011 Medicare schedules. Facility costs were generated by technique based on ICD-9 codes. Incremental cost effectiveness ratios (ICER), which compares cost with clinical outcomes, were calculated according to the difference in reimbursement to the criteria being evaluated. Results:With a median follow-up of 3.6 years, the 5-year rate of local recurrence was 1.9% for all patients (3D-CRT, 0%; BB, 4.1%; P=0.23). When pooled, BB patients had a significant improvement in excellent/good cosmesis (91.6% vs. 80.0%; P=0.03). Rates of combined grade 2 or higher dermatitis, hyper/hypopigmentation, pain, or fibrosis per technique were 62%, 28%, and 34% for 3D-CRT, SL, and ML patients, respectively (P=0.26). The ICER per percent improved cosmesis for SL/ML was

Brachytherapy-based Accelerated Partial Breast Irradiation Provides Equivalent 10-Year Outcomes to Whole Breast Irradiation: A Matched-Pair Analysis.

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Outcome After Ipsilateral Breast Tumor Recurrence in Patients With Early-Stage Breast Cancer Treated With Accelerated Partial Breast Irradiation

850 based on reimbursement and

Seven-Year Outcomes Following Accelerated Partial Breast Irradiation Stratified by ASTRO Consensus Groupings.

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Outcomes of patients with triple-negative breast cancer treated with radiation therapy.

643 based on cost compared with 3D-CRT. Conclusions:On the basis of ICER, brachytherapy for APBI is a cost-effective option with regard to cosmesis and toxicity. This economic analysis suggests the increased cost of applicator-based brachytherapy may be justified in appropriately selected patients.

Accelerated partial-breast irradiation (APBI) versus whole-breast irradiation (WBI) in treatment of the biological subtypes of breast cancer: An analysis of comparative effectiveness.

Introduction:Although whole breast irradiation (WBI) represents the standard radiotherapy technique in breast conserving therapy, accelerated partial breast irradiation (APBI) has emerged as an option to reduce treatment duration with comparable clinical outcomes. The purpose of this analysis is to present long-term clinical outcomes between WBI and APBI. Methods:A total of 3009 patients were treated with breast conserving therapy at a single institution between 1980 and 2012. Among them, 2528 patients received WBI and 481 received APBI (interstitial or balloon based). A matched-pair analysis was performed with patients matched by age (±3 years), stage (T-stage vs. T1 vs. T2), and estrogen receptor status (+/−). All patients had a minimum of 12 months follow-up. A total of 274 matches (ratio 1:1) were made. Results:No differences between groups were noted with respect to clinicopathologic features; WBI patients demonstrated a trend for slightly larger tumors (1.3 vs. 1.1 cm, P=0.06). At 10 years, no differences were noted with respect to rates of ipsilateral breast tumor recurrence (4% vs. 4%, P=0.11), regional recurrence (1% vs. 1%, P=0.20), contralateral breast failure (9% vs. 3%, P=0.06), or distant metastases (3% vs. 6%, P=0.47) for WBI and APBI, respectively. In addition, 10-year disease-free survival (93% vs. 91%, P=0.10) and overall survival (83% vs. 75%, P=0.34) were similar. Long-term cosmesis was good to excellent in 94% of WBI patients versus 95% of APBI patients (P=0.78). Conclusions:At 10 years, no differences in recurrence or survival were found between patients undergoing WBI or brachytherapy-based APBI.

Dosimetric predictors of toxicity and cosmesis in women treated with hypofractionated whole-breast irradiation.

PURPOSE Limited outcomes exist in patients who develop an ipsilateral breast tumor recurrence (IBTR) after accelerated partial breast irradiation (APBI). The purpose of this study was to evaluate these outcomes and patterns of failure in our cohort of patients undergoing APBI. METHODS AND MATERIALS A total of 534 patients with early-stage breast cancer were treated with APBI between 1993 and 2010. Clinical, pathologic, and treatment-related variables were analyzed. Clinical outcomes, including further IBTR, regional recurrence, disease-free survival, cause-specific survival, and overall survival were analyzed. RESULTS Eighteen (3.3%) patients developed an IBTR, for a 5-year actuarial rate of 2.0%; 14 (77.8%) of the recurrences were thought to represent new primary cancers. After IBTR, 13 (72.2%) patients were managed with salvage mastectomy and 4 (22.2%) patients with a second attempt at breast-conserving therapy. Five-year rates of disease-free survival, cause-specific survival, and overall survival after salvage mastectomy for IBTR were 81%, 100%, and 100%, respectively. In the 4 patients treated with a second attempt at breast-conserving therapy, no IBTR, axillary failure, regional recurrence, or distant metastases were noted at 5 years. CONCLUSIONS IBTRs that developed after APBI resulted in excellent clinical outcomes comparable with those observed after whole-breast irradiation.

Clinical efficacy of accelerated partial-breast irradiation in treatment of ER-negative breast cancer: Results of a matched pair analysis.

Objectives: Limited long-term data exist regarding outcomes for patients treated with accelerated partial breast irradiation (APBI), particularly, when stratified by American Society for Radiation Oncology (ASTRO) Consensus Statement (CS) risk groups. The purpose of this analysis is to present 5- and 7-year outcomes following APBI based on CS groupings. Materials and Methods: A total of 690 patients with early-stage breast cancer underwent APBI from 1993 to 2012, receiving interstitial brachytherapy (n=195), balloon-based brachytherapy (n=290), or 3-dimensional conformal radiotherapy (n=205) at a single institution. Patients were stratified into suitable, cautionary, and unsuitable groups with 5-year outcomes analyzed. Seven-year outcomes were analyzed for a subset with follow-up of ≥2 years (n=625). Results: Median follow-up was 6.7 years (range, 0.1 to 20.1 y). Patients assigned to cautionary and unsuitable categories were more likely to have high-grade tumors (21% to 25% vs. 9%, P=0.001), receive chemotherapy (15% to 38% vs. 6%, P<0.001), and have close/positive margins (9% to 11% vs. 0%, P<0.001). There was no difference in ipsilateral breast tumor recurrence at 5 or 7 years: 2.2%, 1.2%, 2.8% at 5 years (P=0.57), and 2.2%, 1.9%, 4.6% at 7 years (P=0.58) in the suitable, cautionary, and unsuitable groups, respectively. As compared with the suitable group, increased rates of distant metastases were noted for the unsuitable and cautionary groups at 5 years (P=0.04). Conclusions: No differences in rates of ipsilateral breast tumor recurrence were seen at 5 or 7 years when stratified by ASTRO CS groupings. Modest increases in distant recurrence were noted in the cautionary and unsuitable groups. These findings suggest that the ASTRO CS groupings stratify more for systemic recurrence and may not appropriately select patients for whole versus partial breast irradiation.