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Dive into the research topics where Keith Robert Unger is active.

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Featured researches published by Keith Robert Unger.


American Journal of Clinical Oncology | 2017

Stereotactic Body Radiation Therapy (sbrt) Combined With Chemotherapy for Unresected Pancreatic Adenocarcinoma.

Marie Kate Gurka; Christine M Kim; Aiwu Ruth He; Aline Charabaty; Nadim Haddad; Jenna Turocy; Lynt B. Johnson; Patrick G. Jackson; Louis M. Weiner; John Marshall; Sean P. Collins; Michael J. Pishvaian; Keith Robert Unger

Objectives: The role of radiation therapy in the management of unresectable pancreatic cancer is controversial. One concern about concurrent chemoradiation relates to the timing of chemotherapy. In contrast to conventional radiation therapy, stereotactic body radiation therapy (SBRT) delivers high doses in a shorter duration resulting in minimal disruption in chemotherapy. Here, we report our results of patients treated with SBRT and chemotherapy for inoperable pancreatic cancer. Materials and Methods: Thirty-eight patients treated with SBRT and chemotherapy for locally advanced, borderline resectable, and medically inoperable pancreatic cancer at our institution from January 2008 to December 2012 were included in this retrospective analysis. Treatment was delivered in 5 fractions of 5 or 6 Gy per fraction over 5 days. Toxicities were scored using the Common Terminology Criteria for Adverse Events version 3. Survival was calculated using the Kaplan-Meier method. Results: The median age was 70 years (range, 45 to 90 y). Eastern Cooperative Oncology Group performance status ranged from 0 to 3. Thirty-four patients received concurrent chemotherapy. Four patients received sequential chemotherapy. Median overall survival was 14.3 months and median progression-free survival was 9.2 months from diagnosis. From radiation, overall survival and progression-free survival were 12.3 and 6.8 months, respectively. The overall local control rate was 79%. Acute toxicity was minimal. Severe late SBRT-related toxicities included 1 grade 3 gastric outlet obstruction, 1 grade 4 biliary stricture, and 1 grade 5 gastric hemorrhage. Conclusions: SBRT combined with chemotherapy for unresectable pancreatic cancer is convenient, feasible, and generally well tolerated. Outcomes of SBRT combined with chemotherapy compare favorably to results obtained with chemotherapy and conventional radiation therapy.


BMC Cancer | 2016

Incorporating Yttrium-90 trans-arterial radioembolization (TARE) in the treatment of metastatic pancreatic adenocarcioma: a single center experience

Alexander Y. Kim; Keith Robert Unger; Hongkun Wang; Michael J. Pishvaian

BackgroundThe purpose of this retrospective study was to evaluate the efficacy of incorporating trans-arterial radioembolization (TARE) with systemic chemotherapy in the treatment of liver-dominant metastatic pancreatic ductal adenocarcinoma, with the aim of destroying liver metastases and improving patient outcomes.MethodsWe retrospectively evaluated 16 patients with liver-dominant metastatic pancreatic ductal adenocarcinoma who underwent TARE between February 2012 and August 2015; 15 of these patients also underwent concurrent systemic chemotherapy. Patient outcomes were assessed using Response Evaluation Criteria In Solid Tumors (RECIST), Version 1.1 and included disease response, median overall survival from the time of diagnosis of metastatic disease, and median overall survival following receipt of TARE. Treatment-related adverse events were assessed using Common Terminology Criteria for Adverse Events (CTCAE), Version 4.03.ResultsThe median overall survival from the time of diagnosis of metastatic disease and following receipt of TARE was 22.0 and 12.5xa0months, respectively. Overall and liver specific disease response were assessed for 13 patients with follow-up imaging available at the time of study (range 2–13 weeks post TARE). Four patients (31xa0%) demonstrated partial response and five patients (38xa0%) had stable disease in the liver at follow-up. One patient developed grade 3 elevation of total bilirubin three months post-treatment and another patient developed radiation cholecystitis directly following TARE. No treatment-related grade 4 or 5 toxicities were seen.ConclusionTARE can be safely combined with systemic chemotherapy for the treatment of liver-dominant metastatic pancreatic cancer. Patient outcomes following this treatment strategy are promising but prospective evaluations are needed to validate these preliminary findings.


Journal of gastrointestinal oncology | 2017

Radiation therapy for hepatobiliary malignancies

Jonathan W. Lischalk; Michael C. Repka; Keith Robert Unger

Hepatobiliary malignancies represent a heterogeneous group of diseases, which often arise in a background of underlying hepatic dysfunction complicating their local management. Surgical resection continues to be the standard of care for hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC); unfortunately the majority of patients are inoperable at presentation. The aggressiveness of these lesions makes locoregional control of particular importance. Historical experience with less sophisticated radiotherapy resulted in underwhelming efficacy and oftentimes prohibitive liver toxicity. However, with the advent of extremely conformal and precise radiotherapy delivery, dose escalation to the tumor with sparing of surrounding normal tissue has yielded notable improvements in efficacy for this modality of treatment. Dose escalation has come in a variety of forms most notably as stereotactic body radiation therapy (SBRT) and hypofractionated proton therapy. As radiation techniques continue to improve, their proper incorporation into the local management of hepatobiliary malignancies will be paramount in improving the prognosis of what is a grave diagnosis.


Frontiers in Surgery | 2017

Gastric Adenocarcinoma: A Multimodal Approach

Humair S. Quadri; Brandon G. Smaglo; Shannon Morales; Anna Chloe Phillips; Aimee D. Martin; Walid M. Chalhoub; Nadim Haddad; Keith Robert Unger; Angela D. Levy

Despite its declining incidence, gastric cancer (GC) remains a leading cause of cancer-related deaths worldwide. A multimodal approach to GC is critical to ensure optimal patient outcomes. Pretherapy fine resolution contrast-enhanced cross-sectional imaging, endoscopic ultrasound and staging laparoscopy play an important role in patients with newly diagnosed ostensibly operable GC to avoid unnecessary non-therapeutic laparotomies. Currently, margin negative gastrectomy and adequate lymphadenectomy performed at high volume hospitals remain the backbone of GC treatment. Importantly, adequate GC surgery should be integrated in the setting of a multimodal treatment approach. Treatment for advanced GC continues to expand with the emergence of additional lines of systemic and targeted therapies.


CardioVascular and Interventional Radiology | 2018

Comparison of Cone-Beam Tomography and Cross-Sectional Imaging for Volumetric and Dosimetric Calculations in Resin Yttrium-90 Radioembolization

Marco Ertreo; Hailey Choi; D. Field; Jonathan W. Lischalk; E. Cohen; G. Lynskey; T. Caridi; Donna Buckley; Keith Robert Unger; Alexander Y. Kim

PurposeTo compare the use of cone-beam computed tomography versus contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) in the calculation of liver volume and planned dose for yttrium-90 radioembolization.Materials and MethodsThe study retrospectively assessed 47 consecutive patients who underwent resin Y-90 radioembolization consecutively over a 2-year period at a single center. Volume calculation software was used to determine perfused lobar liver volumes from cone-beam CT (CBCT) images obtained during mapping angiography. CBCT-derived volumes were compared with perfused lobar volume derived from contrast-enhanced CT and MRI. Nominal activities as determined by the SIR-Spheres Microspheres Activity Calculator were similarly calculated and compared using both CBCT and conventionally acquired volumes.ResultsA total of 82 hepatic lobes were assessed in 47 patients. The mean percentage difference between combined CT-MRI- and CBCT-derived calculated lobar volumes was 25.3% (pu2009=u20090.994). The mean percentage difference in calculated dose between the two methods was 21.8u2009±u200924.6% (pu2009=u20090.42). Combined left and right lobar CT-derived dose difference was less than 10% in 22 lobes, between 10 and 25% in 20 lobes, between 25 and 50% in 13 lobes and greater than 50% in 5 lobes. Combined left and right lobar MRI-derived dose difference was less than 10% in 11 lobes, between 10 and 25% in 7 lobes, between 25 and 50% in 2 lobes and greater than 50% in 1 lobe.ConclusionsAlthough volume measurements derived from CT/MRI did not differ significantly from those derived from CBCT, variability between the two methods led to large and unexpected differences in calculated dose.


Journal of Clinical Oncology | 2012

Quality of life and acute radiation toxicity following hypofractionated stereotactic body radiation therapy with concurrent full-dose gemcitabine for unresectable pancreatic adenocarcinoma.

Marie Kate Gurka; Gary Tse; Keith Robert Unger; Nadim Haddad; John Marshall; C. D. Johnson; Lisa Ley; Rebecca Slack; Michael J. Pishvaian; Sean P. Collins

336 Background: Quality of life (QoL) is of paramount importance when cure is not obtainable. The aim of this study is to report QoL outcomes and acute radiation toxicity in patients with pancreatic cancer treated with stereotactic body radiation therapy (SBRT) and concurrent gemcitabine.nnnMETHODSnThis prospective study reviewed the charts of 10 patients with locally advanced, unresectable pancreatic cancer treated with SBRT and 6 cycles of gemcitabine. The primary tumor and adjacent para-aortic nodes received a total dose of 2500 cGy in 500 cGy fractions on consecutive days between cycles 1 and 2 of gemcitabine. QoL was assessed on the 1st day of each cycle using the EORTC QLQ-C30 and EORTC QLQ-PAN26 questionnaires. Wilcoxon rank sum test was used to determine statistical significance between QoL scores. Toxicity was graded by NCI Common Terminology Criteria for Adverse Events, Version 3.0.nnnRESULTSnThe median age was 62.5 years. All patients completed the prescribed SBRT. Median overall survival was 13 months (range 5- 17). QoL scores at baseline compared to immediately after SBRT showed an increase in the following symptoms: fatigue, nausea/vomiting (N/V) and anorexia, which were statistically significant (P < 0.05). These were not statistically different from baseline by cycle 3 except N/V. No symptoms were significantly improved after radiation therapy; however, there was a trend towards improvement in back pain, night pain and abdominal discomfort. Functional scales declined after treatment, but not significantly. Global QoL did not significantly change from baseline. There were no grade 3 or 4 acute toxicities related to SBRT.nnnCONCLUSIONSnHypofractionated SBRT with concurrent gemcitabine is feasible for locally advanced, unresectable pancreatic cancer. There is a temporary increase in selected symptoms due to radiation which resolve within one month. This may be an improvement compared to conventional fractionated radiation due to shorter duration of symptoms related to radiation treatment.


Journal of Clinical Oncology | 2014

Stereotactic body radiation therapy (SBRT) combined with chemotherapy for locally advanced pancreatic adenocarcinoma.

Marie Kate Gurka; Christine M Kim; Nadim Haddad; John Carroll; Aline Charabaty; Patrick G. Jackson; K. William Harter; Jimmy J. Hwang; Louis M. Weiner; John Marshall; Sean P. Collins; Michael J. Pishvaian; Keith Robert Unger


Oncology Times UK | 2018

An Update in the Management of Retroperitoneal Soft Tissue Sarcoma

Anthony M. Villano; Kathryn M. Maselli; Angela D. Levy; Keith Robert Unger; Dennis A. Priebat; Raphael E. Pollock; Waddah B. Al-Refaie


Journal of The American College of Surgeons | 2018

Hospital Factors and Sources of Variation in Mortality After Treatment of Retroperitoneal Soft-Tissue Sarcoma: Results Beyond TNM Staging

Anthony M. Villano; Alexander Zeymo; Kitty Chan; Nawar Shara; Keith Robert Unger; Waddah B. Al-Refaie


Journal of Clinical Oncology | 2018

Molecular profiling to predict outcomes following Y90 radioembolization for metastatic colorectal cancer.

Petra Prins; Alexandra Gradzka; Alexander Y. Kim; John Marshall; Keith Robert Unger

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Michael J. Pishvaian

Georgetown University Medical Center

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Alexander Y. Kim

MedStar Georgetown University Hospital

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Nadim Haddad

MedStar Georgetown University Hospital

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Jonathan W. Lischalk

MedStar Georgetown University Hospital

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Aiwu Ruth He

Georgetown University Medical Center

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