Browsing by Author "Chang, Michael"

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    Challenges and Opportunities in Developing an Oncology Clinical Trial Network in the United States Veterans Affairs Health Care System: The VA STARPORT Experience
    (MDPI, 2024-08-21) Solanki, Abhishek A.; Zheng, Kevin; Skipworth, Alicia N.; Robin, Lisa M.; Leparski, Ryan F.; Henry, Elizabeth; Rettig, Matthew; Salama, Joseph K.; Ritter, Timothy; Jones, Jeffrey; Quek, Marcus; Chang, Michael; Block, Alec M.; Welsh, James S.; Kumar, Aryavarta; Chao, Hann-Hsiang; Chen, Albert C.; Shapiro, Ronald; Bitting, Rhonda L.; Kwon, Robert; Stross, William; Puckett, Lindsay; Wong, Yu-Ning; Nickols, Nicholas G.; Carlson, Kimberly; VA STARPORT Investigators Group; Radiation Oncology, School of Medicine
    The United States Veterans Affairs (VA) Health Care System has a strong history of conducting impactful oncology randomized clinical trials (RCTs). We developed a phase II/III RCT to test the use of metastasis-directed therapy in Veterans with oligometastatic prostate cancer (OMPC)-the first VA RCT in OMPC that leverages novel imaging and advanced radiotherapy techniques. To accomplish this, we developed a clinical trial network to conduct the study. In this manuscript, we describe several challenges we encountered in study development/conduct and our strategies to address them, with the goal of helping investigators establish robust study networks to conduct clinical trials. In the study start-up, we encountered challenges in timely site activation, and leveraged project management to maximize efficiency. Additionally, there were several changes in the clinical paradigms in imaging and treatment that led to protocol amendments to ensure maximum equipoise, recruitment, and impact of the study. Specifically, we amended the trial to add de novo OMPC patients (from initially only recurrent OMPC) and expanded the study to allow up to 10 metastases (from initially five). Finally, in order to maintain local study team engagement, we developed initiatives to maximize collaboration and add value to the overall clinical program through study participation.
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    Regional Vessel Density Reduction in the Macula and Optic Nerve Head of Patients With Pre-Perimetric Primary Open Angle Glaucoma
    (Wolters Kluwer, 2023) Verticchio Vercellin, Alice; Siesky, Brent; Antman, Gal; Oddone, Francesco; Chang, Michael; Eckert, George; Arciero, Julia; Kellner, Rebecca L.; Fry, Brendan; Coleman-Belin, Janet; Carnevale, Carmela; Harris, Alon; Biostatistics and Health Data Science, Richard M. Fairbanks School of Public Health
    Purpose: To investigate optic nerve head (ONH) and macular vessel densities (VD) and structural parameters assessed by optical coherence tomography angiography (OCTA) in pre-perimetric open-angle glaucoma (ppOAG) patients and healthy controls. Methods: 113 healthy and 79 ppOAG patients underwent global and regional (hemispheric/quadrants) assessments of retinal, ONH, and macular vascularity and structure, including ONH parameters, retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness. Comparisons between outcomes in ppOAG and controls were adjusted for age, sex, race, BMI, diabetes, and hypertension, with p<0.05 considered statistically significant. Results: In ppOAG compared to healthy controls: RNFL thicknesses was statistically significantly lower for all hemispheres, quadrants and sectors (p<0.001–0.041); whole image peripapillary all and small blood vessels VD were statistically significantly lower for all the quadrants (p<0.001–0.002), except for the peripapillary small vessels in the temporal quadrant (ppOAG: 49.66 (8.40), healthy: 53.45 (4.04); p=0.843); GCC and inner and full macular thicknesses in the parafoveal and perifoveal regions were significantly lower in all the quadrants (p=0.000-p=0.033); several macular VD were significantly lower (p=0.006–0.034), with the exceptions of macular center, parafoveal superior and inferior quadrant, and perifoveal superior quadrant (p>0.05). Conclusions: In ppOAG patients, VD biomarkers in both the macula and ONH, alongside RNFL, GCC, and macular thickness were significantly reduced prior to detectable VF loss with regional specificity. The most significant VD reduction detected was in the peripheric (perifovea) regions. Macular and ONH decrease in VD may serve as early biomarker of glaucomatous disease.