J.L. Fox

Spine stereotactic body radiation therapy plans: Achieving dose coverage, conformity, and dose falloff

We report our experience of establishing planning objectives to achieve dose coverage, conformity, and dose falloff for spine stereotactic body radiation therapy (SBRT) plans. Patients with spine lesions were treated using SBRT in our institution since September 2009. Since September 2011, we established the following planning objectives for our SBRT spine plans in addition to the cord dose constraints: (1) dose coverage—prescription dose (PD) to cover at least 95% planning target volume (PTV) and 90% PD to cover at least 99% PTV; (2) conformity index (CI)—ratio of prescription isodose volume (PIV) to the PTV < 1.2; (3) dose falloff—ratio of 50% PIV to the PTV (R(50%)); (4) and maximum dose in percentage of PD at 2 cm from PTV in any direction (D(2cm)) to follow Radiation Therapy Oncology Group (RTOG) 0915. We have retrospectively reviewed 66 separate spine lesions treated between September 2009 and December 2012 (31 treated before September 2011 [group 1] and 35 treated after [group 2]). The χ(2) test was used to examine the difference in parameters between groups. The PTV V(100% PD) ≥ 95% objective was met in 29.0% of group 1 vs 91.4% of group 2 (p < 0.01) plans. The PTV V(90% PD) ≥ 99% objective was met in 38.7% of group 1 vs 88.6% of group 2 (p < 0.01) plans. Overall, 4 plans in group 1 had CI > 1.2 vs none in group 2 (p = 0.04). For D(2cm), 48.3% plans yielded a minor violation of the objectives and 16.1% a major violation for group 1, whereas 17.1% exhibited a minor violation and 2.9% a major violation for group 2 (p < 0.01). Spine SBRT plans can be improved on dose coverage, conformity, and dose falloff employing a combination of RTOG spine and lung SBRT protocol planning objectives.

Fractionated stereotactic radiation therapy for brain metastases: a systematic review with tumour control probability modelling

OBJECTIVE Fractionated stereotactic radiotherapy (FSRT) is a relatively new option for the treatment of brain metastases. We performed a quantitative systematic review to determine if local control (LC) following is affected by FSRT dosing regimen. METHODS We reviewed articles describing LC following FSRT for brain metastases. LC data from each study were extracted from actuarial survival curves and aggregated to form a single data set. LC curves were generated using the Kaplan-Meier method. Log-rank testing and Cox proportional hazards modelling were utilized to test for associations between the biologically effective dose (BED) and LC. Tumour control probability modelling was performed to illustrate the relationship between the BED and the likelihood of LC after FSRT. RESULTS 10 studies (720 metastases) met inclusion criteria. Prescription doses ranged from 18 to 42 Gy, delivered in 3-12 fractions (BED range: 29-100 Gy10). 1- and 2-year actuarial LC rates were 80% and 69%, respectively. Increasing BED was associated with improved LC (HR = 0.77 per increase of 10 Gy10, p = 0.009). Tumour control probability models demonstrated that the BEDs of 40, 50 and 60 Gy10 yield predicted 1-year LC rates of 73%, 78% and 84%, respectively. The BEDs of 40, 50 and 60 Gy10 yield 2-year LC rates of 62%, 69% and 81%, respectively. CONCLUSION FSRT provides high rates of LC for patients with brain metastases. We found evidence for a dose-response relationship that should be explored in prospective trials. Advances in knowledge: This review identified a dose-response relationship for LC in patients treated with FSRT for brain metastases.

BRAF inhibitor (vemurafenib) concurrent with radiation therapy for metastatic melanoma producing severe skin and oral cavity reactions

An 80-year-old female presented in November 2010 with a 2-year history of an enlarging left shoulder lesion. Biopsy revealed malignant melanoma, while resection demonstrated invasive melanoma, 3.8-mm thick (Clark level IV), with negative margins of ≥ 1 cm. Surveillance PET/CT (positron emission tomography/computed tomography) in May 2011 suggested recurrence at a left level IV cervical lymph node. Left neck dissection revealed 1/21 level III nodes positive for disease plus a 1.0-cm lesion in the superficial dermis within level V. The tumors tested positive for the BRAFV600E mutation. She was started on the human monoclonal antibody ipilimumab (Yervoy) in October 2011 for 4 cycles. The PET/CT in February 2012 and magnetic resonance imaging revealed local and distant progression. The patient started palliative radiation therapy (50 Gy/ 20 fractions to the left neck) in March to April 2012 (Fig 1). Concurrently, she was started on the BRAF inhibitor vemurafenib (Zelboraf). Toward the end

The DCIS score: Potential for health care savings?

35 Background: The Oncotype Dx Recurrence Score for DCIS (DCIS Score) is a 12-gene assay derived from the original Oncotype DX test. The DCIS Score provides a local recurrence risk estimate at 10 years after lumpectomy for DCIS. Results can guide decisions regarding adjuvant radiation (RT). Foregoing RT can be a source of significant healthcare savings. We investigated the actual healthcare dollar savings to-date in our patients. METHODS We evaluated patients in whom the DCIS Score was ordered (x) and calculated total cost of testing. Potential cost of RT was that of IMRT as reimbursed by Medicare for a 16 fraction course, multiplied by x. Many of our patients with large breasts require IMRT for dose homogeneity and normal tissue parameters. We also calculated potential cost with 3D conformal (3D-CRT). Total potential cost was the sum of testing and treatment costs, determined for each modality. The number of patients ultimately treated (y) was also multiplied by these costs. Total actual cost was the sum of test expenses and actual treatment costs. Savings was the difference between total actual and total potential cost. RESULTS From 2/2012 to 5/ 2014 the DCIS Score was performed in 38 patients (x = 38). Median age was 66 (40 to 85). Grade was low in 39%, intermediate in 45%, and high in 16%. Fifty percent had necrosis and median size was 0.5 cm (0.1 to 3.1cm). The total cost of testing was

Neoadjuvant radiation therapy for the management of myoepithelial carcinoma of the upper extremity: Neoadjuvant radiation therapy

4125 * 38 =

Tumor bed variation during multi-lumen balloon-based accelerated partial breast irradiation: implication of surgical clips

156,750. IMRT reimburses at

Abstract P6-13-08: The DCIS Score - Potential for healthcare savings?

23, 000 and 3D-CRT at

TU‐F‐18C‐09: Mammogram Surveillance Using Texture Analysis for Breast Cancer Patients After Radiation Therapy

11,000. Potential total cost of RT ranged from

Recurrence patterns among T1-2N0 triple-negative breast cancer patients following mastectomy.

418,000 to

Dosimetric comparison of 3D-field-in-field technique and inverse planning IMRT for large-breasted patients treated in prone position.

874, 000; testing brought total potential costs to