John Kirkpatrick

Overview:

Malignant and benign tumors of the brain, spine and base of skull. Mathematical modelling of tumor metabolism, mass transfer and the response to ionizing radiation. Enhancing clinical outcome in stereotactic radiosurgery, fractionated stereotactic radiotherapy and stereotactic body radiotherapy.

Positions:

Professor of Radiation Oncology

Radiation Oncology
School of Medicine

Professor in Neurosurgery

Neurosurgery
School of Medicine

Member of the Duke Cancer Institute

Duke Cancer Institute
School of Medicine

Education:

Ph.D. 1978

Rice University

M.D. 1999

University of Texas Health Science Center San Antonio

Grants:

Validation of Novel Therapeutic Approach for Leptomeningeal Metastases

Administered By
Neurosurgery
Role
Investigator
Start Date
End Date

BMX-001 AS A THERAPEUTIC AGENT FOR TREATMENT OF MULTIPLE BRAIN METASTASES

Administered By
Radiation Oncology
Role
Principal Investigator
Start Date
End Date

Publications:

Arteriovenous Malformation: A Real Can of Worms.

Authors
Trotter, JW; Kirkpatrick, JP
MLA Citation
Trotter, Jacob W., and John P. Kirkpatrick. “Arteriovenous Malformation: A Real Can of Worms.Int J Radiat Oncol Biol Phys, vol. 111, no. 4, Nov. 2021, pp. 851–53. Pubmed, doi:10.1016/j.ijrobp.2018.08.068.
URI
https://scholars.duke.edu/individual/pub1499729
PMID
34655559
Source
pubmed
Published In
Int J Radiat Oncol Biol Phys
Volume
111
Published Date
Start Page
851
End Page
853
DOI
10.1016/j.ijrobp.2018.08.068

Primary brain tumor patients admitted to a US intensive care unit: a descriptive analysis.

Purpose: To describe our population of primary brain tumor (PBT) patients, a subgroup of cancer patients whose intensive care unit (ICU) outcomes are understudied. Methods: Retrospective analysis of PBT patients admitted to an ICU between 2013 to 2018 for an unplanned need. Using descriptive analyses, we characterized our population and their outcomes. Results: Fifty-nine PBT patients were analyzed. ICU mortality was 19% (11/59). The most common indication for admission was seizures (n = 16, 27%). Conclusion: Our ICU mortality of PBT patients was comparable to other solid tumor patients and the general ICU population and better than patients with hematological malignancies. Further study of a larger population would inform guidelines for triaging PBT patients who would most benefit from ICU-level care.
Authors
Kang, JH; Swisher, CB; Buckley, ED; Herndon, JE; Lipp, ES; Kirkpatrick, JP; Desjardins, A; Friedman, HS; Johnson, MO; Randazzo, DM; Ashley, DM; Peters, KB
MLA Citation
Kang, Jennifer H., et al. “Primary brain tumor patients admitted to a US intensive care unit: a descriptive analysis.Cns Oncol, vol. 10, no. 3, Sept. 2021, p. CNS77. Pubmed, doi:10.2217/cns-2021-0009.
URI
https://scholars.duke.edu/individual/pub1497219
PMID
34545753
Source
pubmed
Published In
Cns Oncology
Volume
10
Published Date
Start Page
CNS77
DOI
10.2217/cns-2021-0009

Hippocampal Avoidance in Multitarget Radiosurgery.

Brain metastases are a common complication for patients diagnosed with cancer. As stereotactic radiosurgery (SRS) becomes a more prevalent treatment option for patients with many brain metastases, further research is required to better characterize the ability of SRS to treat large numbers of metastases (≥4) and the impact on normal brain tissue and, ultimately, neurocognition and quality of life (QOL). This study serves first as an evaluation of the feasibility of hippocampal avoidance for SRS patients, specifically receiving single-isocenter multitarget treatments (SIMT) planned with volumetric modulated arc therapy (VMAT). Second, this study analyzes the effects of standard-definition (SD) multileaf collimators (MLCs) (5 mm width) on plan quality and hippocampal avoidance. The 40 patients enrolled in this Institutional Review Board (IRB)-approved study had between four and 10 brain metastases and were treated with SIMT using VMAT. From the initial 40 patients, eight hippocampi across seven patients had hippocampal doses exceeding the maximum biologically effective dose (BED) constraint given by RTOG 0933. With the addition of upper constraints in the optimization objectives and one arc angle adjustment in one patient plan, four out of seven patient plans were able to meet the maximum hippocampal BED constraint, avoiding five out of eight total hippocampi at risk. High-definition (HD) MLCs allowed for an average decrease of 29% ± 23% (p = 0.007) in the maximum BED delivered to all eight hippocampi at risk. The ability to meet dose constraints depended on the distance between the hippocampus and the nearest planning target volume (PTV). Meeting the maximum hippocampal BED constraint in re-optimized plans was equally likely with the use of SD-MLCs (five out of eight hippocampi at risk were avoided) but resulted in increased dose to normal tissue volumes (23.67% ± 16.3% increase in V50%[cc] of normal brain tissue, i.e., brain volume subtracted by the total PTV) when compared to the HD-MLC re-optimized plans. Comparing the effects of SD-MLCs on plans not optimized for hippocampal avoidance resulted in increases of 48.2% ± 32.2% (p = 0.0056), 31.5% ± 16.3% (p = 0.024), and 16.7% ± 8.5% (p = 0.022) in V20%[cc], V50%[cc], and V75%[cc], respectively, compared to the use of HD-MLCs. The conformity index changed significantly neither when plans were optimized for hippocampal avoidance nor when SD-MLC leaves were used for treatment. In plans not optimized for hippocampal avoidance, mean hippocampal dose increased with the use of SD-MLCs by 38.0% ± 37.5% (p = 0.01). However, the use of SD-MLCs did not result in an increased number of hippocampi at risk.
Authors
Gude, Z; Adamson, J; Kirkpatrick, JP; Giles, W
MLA Citation
Gude, Zachary, et al. “Hippocampal Avoidance in Multitarget Radiosurgery.Cureus, vol. 13, no. 6, June 2021, p. e15399. Pubmed, doi:10.7759/cureus.15399.
URI
https://scholars.duke.edu/individual/pub1488949
PMID
34249548
Source
pubmed
Published In
Cureus
Volume
13
Published Date
Start Page
e15399
DOI
10.7759/cureus.15399

Primary brain tumors admitted to the neurological intensive care unit: a single institution observational study.

Authors
Kang, J; Swisher, C; Kirkpatrick, J; Herndon, J; Lipp, E; Thomas, L; Johnson, MO; Ashley, D; Desjardins, A; Randazzo, D; Friedman, H; Peters, K
MLA Citation
Kang, J., et al. “Primary brain tumors admitted to the neurological intensive care unit: a single institution observational study.Neurology, vol. 92, no. 15, American Academy of Neurology, 2019, p. P1.6-009-P1.6-009.
URI
https://scholars.duke.edu/individual/pub1459067
Source
manual
Published In
Neurology
Volume
92
Published Date
Start Page
P1.6-009
End Page
P1.6-009

Radiosurgery treatment planning using conformal arc informed volumetric modulated arc therapy.

Linac based radiosurgery to multiple metastases is commonly planned with volumetric modulated arc therapy (VMAT) as it effectively achieves high conformality to complex target arrangements. However, as the number of targets increases, VMAT can struggle to block between targets, which can lead to highly modulated and/or nonconformal multi-leaf collimator (MLC) trajectories that unnecessarily irradiation of healthy tissue. In this study we introduce, describe, and evaluate a treatment planning technique called Conformal Arc Informed VMAT (CAVMAT), which aims to reduce the dose to healthy tissue while generating highly conformal treatment plans. CAVMAT is a hybrid technique which combines the conformal MLC trajectories of dynamic conformal arcs with the MLC modulation and versatility of inverse optimization. CAVMAT has 3 main steps. First, targets are assigned to subgroups to maximize MLC blocking between targets. Second, arc weights are optimized to achieve the desired target dose, while minimizing MU variation between arcs. Third, the optimized conformal arc plan serves as the starting point for limited inverse optimization to improve dose conformity to each target. Twenty multifocal VMAT cases were replanned with CAVMAT with 20Gy applied to each target. The total volume receiving 2.5Gy[cm3], 6Gy[cm3], 12Gy[cm3], and 16Gy[cm3], conformity index, treatment delivery time, and the total MU were used to compare the VMAT and CAVMAT plans. In addition, CAVMAT was compared to a broad range of planning strategies from various institutions (108 linear accelerator based plans, 14 plans using other modalities) for a 5-target case utilized in a recent plan challenge. For the linear accelerator-based plans, a plan complexity metric based on aperture opening area and perimeter, total monitor units (MU), and MU for a given aperture opening was utilized in the plan challenge scoring algorithm to compare the submitted plans to CAVMAT. After re-planning the 20 VMAT cases, CAVMAT reduced the average V2.5Gy[cm3] by 25.25 ± 19.23%, V6Gy[cm3] by 13.68 ± 18.97%, V12Gy[cm3] by 11.40 ± 19.44%, and V16Gy[cm3] by 6.38 ± 19.11%. CAVMAT improved conformity by 3.81 ± 7.57%, while maintaining comparable target dose. MU for the CAVMAT plans increased by 24.35 ± 24.66%, leading to an increased treatment time of 2 minutes. For the plan challenge case, CAVMAT was 1 of 12 linac based plans that met all plan challenge scoring criteria. Compared to the average submitted VMAT plan, CAVMAT increased the V10%Gy[%] of healthy tissue (Brain-PTV) by roughly 3.42%, but in doing so was able to reduce the V25%Gy[%] by roughly 3.73%, while also reducing V50%Gy[%], V75%Gy[%], and V100%Gy[%]. The CAVMAT technique successfully eliminated insufficient MLC blocking between targets prior to the inverse optimization, leading to less complex treatment plans and improved tissue sparing. Tissue sparing, improved conformity, and decreased plan complexity at the cost of slight increase in treatment delivery time indicates CAVMAT to be a promising method to treat brain metastases.
Authors
Giles, WM; Cullom, ET; Laryea, OA-O; Nobah, A; Alves, VGL; Yin, F-F; Kirkpatrick, JP; Adamson, JD
MLA Citation
Giles, William M., et al. “Radiosurgery treatment planning using conformal arc informed volumetric modulated arc therapy.Med Dosim, vol. 46, no. 1, pp. 3–12. Pubmed, doi:10.1016/j.meddos.2020.06.001.
URI
https://scholars.duke.edu/individual/pub1456370
PMID
32807612
Source
pubmed
Published In
Med Dosim
Volume
46
Start Page
3
End Page
12
DOI
10.1016/j.meddos.2020.06.001