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Dive into the research topics where Erqi L. Pollom is active.

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Featured researches published by Erqi L. Pollom.


Journal of Clinical Oncology | 2016

Outcomes After Stereotactic Body Radiotherapy or Radiofrequency Ablation for Hepatocellular Carcinoma

Daniel R. Wahl; Matthew H. Stenmark; Yebin Tao; Erqi L. Pollom; Elaine M. Caoili; Theodore S. Lawrence; Matthew Schipper; Mary Feng

PURPOSE Data guiding selection of nonsurgical treatment of hepatocellular carcinoma (HCC) are lacking. We therefore compared outcomes between stereotactic body radiotherapy (SBRT) and radiofrequency ablation (RFA) for HCC. PATIENTS AND METHODS From 2004 to 2012, 224 patients with inoperable, nonmetastatic HCC underwent RFA (n = 161) to 249 tumors or image-guided SBRT (n = 63) to 83 tumors. We applied inverse probability of treatment weighting to adjust for imbalances in treatment assignment. Freedom from local progression (FFLP) and toxicity were retrospectively analyzed. RESULTS RFA and SBRT groups were similar with respect to number of lesions treated per patient, type of underlying liver disease, and tumor size (median, 1.8 v 2.2 cm in maximum diameter; P = .14). However, the SBRT group had lower pretreatment Child-Pugh scores (P = .003), higher pretreatment alpha-fetoprotein levels (P = .04), and a greater number of prior liver-directed treatments (P < .001). One- and 2-year FFLP for tumors treated with RFA were 83.6% and 80.2% v 97.4% and 83.8% for SBRT. Increasing tumor size predicted for FFLP in patients treated with RFA (hazard ratio [HR], 1.54 per cm; P = .006), but not with SBRT (HR, 1.21 per cm; P = .617). For tumors ≥ 2 cm, there was decreased FFLP for RFA compared with SBRT (HR, 3.35; P = .025). Acute grade 3+ complications occurred after 11% and 5% of RFA and SBRT treatments, respectively (P = .31). Overall survival 1 and 2 years after treatment was 70% and 53% after RFA and 74% and 46% after SBRT. CONCLUSION Both RFA and SBRT are effective local treatment options for inoperable HCC. Although these data are retrospective, SBRT appears to be a reasonable first-line treatment of inoperable, larger HCC.


Journal of Clinical Oncology | 2016

Cost-Effectiveness of Pertuzumab in Human Epidermal Growth Factor Receptor 2–Positive Metastatic Breast Cancer

Ben Y. Durkee; Yushen Qian; Erqi L. Pollom; Martin T. King; S.A. Dudley; J. Shaffer; Daniel T. Chang; Iris C. Gibbs; Jeremy D. Goldhaber-Fiebert; Kathleen C. Horst

PURPOSE The Clinical Evaluation of Pertuzumab and Trastuzumab (CLEOPATRA) study showed a 15.7-month survival benefit with the addition of pertuzumab to docetaxel and trastuzumab (THP) as first-line treatment for patients with human epidermal growth factor receptor 2 (HER2) -overexpressing metastatic breast cancer. We performed a cost-effectiveness analysis to assess the value of adding pertuzumab. PATIENT AND METHODS We developed a decision-analytic Markov model to evaluate the cost effectiveness of docetaxel plus trastuzumab (TH) with or without pertuzumab in US patients with metastatic breast cancer. The model followed patients weekly over their remaining lifetimes. Health states included stable disease, progressing disease, hospice, and death. Transition probabilities were based on the CLEOPATRA study. Costs reflected the 2014 Medicare rates. Health state utilities were the same as those used in other recent cost-effectiveness studies of trastuzumab and pertuzumab. Outcomes included health benefits expressed as discounted quality-adjusted life-years (QALYs), costs in US dollars, and cost effectiveness expressed as an incremental cost-effectiveness ratio. One- and multiway deterministic and probabilistic sensitivity analyses explored the effects of specific assumptions. RESULTS Modeled median survival was 39.4 months for TH and 56.9 months for THP. The addition of pertuzumab resulted in an additional 1.81 life-years gained, or 0.62 QALYs, at a cost of


International Journal of Radiation Oncology Biology Physics | 2015

Gastrointestinal Toxicities With Combined Antiangiogenic and Stereotactic Body Radiation Therapy

Erqi L. Pollom; Lei Deng; Reetesh K. Pai; J. Martin Brown; Amato J. Giaccia; Billy W. Loo; D.B. Shultz; Quynh-Thu Le; Albert C. Koong; Daniel T. Chang

472,668 per QALY gained. Deterministic sensitivity analysis showed that THP is unlikely to be cost effective even under the most favorable assumptions, and probabilistic sensitivity analysis predicted 0% chance of cost effectiveness at a willingness to pay of


International Journal of Radiation Oncology Biology Physics | 2016

Quantitative Analysis of 18F-Fluorodeoxyglucose Positron Emission Tomography Identifies Novel Prognostic Imaging Biomarkers in Locally Advanced Pancreatic Cancer Patients Treated With Stereotactic Body Radiation Therapy

Yi Cui; Jie Song; Erqi L. Pollom; Muthuraman Alagappan; Hiroki Shirato; Daniel T. Chang; Albert C. Koong; Ruijiang Li

100,000 per QALY gained. CONCLUSION THP in patients with metastatic HER2-positive breast cancer is unlikely to be cost effective in the United States.


American Journal of Clinical Oncology | 2016

Albumin and Neutrophil-Lymphocyte Ratio (NLR) Predict Survival in Patients With Pancreatic Adenocarcinoma Treated With SBRT

Muthuraman Alagappan; Erqi L. Pollom; Rie von Eyben; Margaret M. Kozak; Sonya Aggarwal; George A. Poultsides; Albert C. Koong; Daniel T. Chang

Combining the latest targeted biologic agents with the most advanced radiation technologies has been an exciting development in the treatment of cancer patients. Stereotactic body radiation therapy (SBRT) is an ablative radiation approach that has become established for the treatment of a variety of malignancies, and it has been increasingly used in combination with biologic agents, including those targeting angiogenesis-specific pathways. Multiple reports have emerged describing unanticipated toxicities arising from the combination of SBRT and angiogenesis-targeting agents, particularly of late luminal gastrointestinal toxicities. In this review, we summarize the literature describing these toxicities, explore the biological mechanism of action of toxicity with the combined use of antiangiogenic therapies, and discuss areas of future research, so that this combination of treatment modalities can continue to be used in broader clinical contexts.


JAMA Dermatology | 2015

Concurrent Vismodegib and Radiotherapy for Recurrent, Advanced Basal Cell Carcinoma

Erqi L. Pollom; Timothy Bui; Anne Lynn S. Chang; A. Dimitrios Colevas; Wendy Hara

PURPOSE To identify prognostic biomarkers in pancreatic cancer using high-throughput quantitative image analysis. METHODS AND MATERIALS In this institutional review board-approved study, we retrospectively analyzed images and outcomes for 139 locally advanced pancreatic cancer patients treated with stereotactic body radiation therapy (SBRT). The overall population was split into a training cohort (n=90) and a validation cohort (n=49) according to the time of treatment. We extracted quantitative imaging characteristics from pre-SBRT (18)F-fluorodeoxyglucose positron emission tomography, including statistical, morphologic, and texture features. A Cox proportional hazard regression model was built to predict overall survival (OS) in the training cohort using 162 robust image features. To avoid over-fitting, we applied the elastic net to obtain a sparse set of image features, whose linear combination constitutes a prognostic imaging signature. Univariate and multivariate Cox regression analyses were used to evaluate the association with OS, and concordance index (CI) was used to evaluate the survival prediction accuracy. RESULTS The prognostic imaging signature included 7 features characterizing different tumor phenotypes, including shape, intensity, and texture. On the validation cohort, univariate analysis showed that this prognostic signature was significantly associated with OS (P=.002, hazard ratio 2.74), which improved upon conventional imaging predictors including tumor volume, maximum standardized uptake value, and total legion glycolysis (P=.018-.028, hazard ratio 1.51-1.57). On multivariate analysis, the proposed signature was the only significant prognostic index (P=.037, hazard ratio 3.72) when adjusted for conventional imaging and clinical factors (P=.123-.870, hazard ratio 0.53-1.30). In terms of CI, the proposed signature scored 0.66 and was significantly better than competing prognostic indices (CI 0.48-0.64, Wilcoxon rank sum test P<1e-6). CONCLUSION Quantitative analysis identified novel (18)F-fluorodeoxyglucose positron emission tomography image features that showed improved prognostic value over conventional imaging metrics. If validated in large, prospective cohorts, the new prognostic signature might be used to identify patients for individualized risk-adaptive therapy.


International Journal of Radiation Oncology Biology Physics | 2015

Value of surveillance studies for patients with stage I to II diffuse large B-cell lymphoma in the rituximab era.

Susan M. Hiniker; Erqi L. Pollom; Michael S. Khodadoust; Margaret M. Kozak; Guofan Xu; Andrew Quon; Ranjana H. Advani; Richard T. Hoppe

Purpose: To determine if pretreatment nutritional status and inflammatory markers correlate with survival in patients with locally advanced pancreatic adenocarcinoma treated with stereotactic body radiotherapy (SBRT). Materials and Methods: We retrospectively reviewed 208 patients with newly diagnosed, locally advanced pancreatic adenocarcinoma treated with SBRT at our institution from 2002 to 2014. Laboratory values were collected before SBRT, including hemoglobin, platelets, albumin, red blood cell, white blood cell, neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio, and tumor markers CA 19-9 and CEA. Patients were followed every 3 months with computed tomography (CT) and/or positron emission tomography-CT imaging to monitor for local recurrence and overall survival (OS). Results: Median follow-up after SBRT was 7.5 months (interquartile range, 4.6 to 12.0 mo) for all patients. Median OS for patients with NLR>5 compared with NLR⩽5 was 6.9 and 8.5 months, respectively (P=0.0057). On univariate analysis, receipt of chemotherapy (P=0.05, hazard ratio [HR]=0.69), increased albumin (P=0.002, HR=0.64), increased red blood cell (P=0.05, HR=0.75), increased lymphocyte count (P=0.002, HR=0.66), decreased CEA (P=0.01, HR=0.96), and NLR⩽5 (P=0.01, HR=0.65) correlated with improved OS. On multivariate analysis, higher albumin (P=0.03, HR=0.70), receipt of chemotherapy (P=0.007, HR=0.56), and NLR⩽5 (P=0.02, HR=0.66) correlated with better survival. Conclusions: Preradiotherapy low albumin levels and NLR>5 correlate with decreased survival in patients with locally advanced pancreatic adenocarcinoma treated with SBRT, indicating the prognostic value of systemic inflammatory markers (such as NLR) and a role of nutritional supplementation to improve outcomes in these patients. Further investigation is warranted.


Seminars in Radiation Oncology | 2017

Normal Tissue Constraints for Abdominal and Thoracic Stereotactic Body Radiotherapy

Erqi L. Pollom; Alexander L. Chin; Maximilian Diehn; Billy W. Loo; Daniel T. Chang

IMPORTANCE Vismodegib is a targeted agent recently approved for treating patients who develop recurrent or locally advanced basal cell carcinoma (BCC), and will inevitably be integrated into existing therapy for advanced BCC as it becomes increasingly used. Improved understanding of how vismodegib interacts with other treatment modalities, including radiotherapy, would help optimize multidisciplinary therapy and clinical outcomes. OBSERVATIONS We report 2 cases of recurrent, advanced BCC treated from April 1, 2012, through October 31, 2014, with concurrent radiotherapy and vismodegib. Concurrent treatment appeared to be well tolerated and efficacious, with both patients having no evidence of progressive disease at last follow-up. CONCLUSIONS AND RELEVANCE We found that the combination of vismodegib and radiotherapy is feasible for patients with recurrent or locally advanced BCC and that combined use of currently available therapies for advanced BCC warrants further prospective study.


Radiology | 2017

Cost-effectiveness of Stereotactic Body Radiation Therapy versus Radiofrequency Ablation for Hepatocellular Carcinoma: A Markov Modeling Study.

Erqi L. Pollom; Kyueun Lee; Ben Y. Durkee; Madeline M. Grade; Daniel Mokhtari; Daniel R. Wahl; Mary Feng; N. Kothary; Albert C. Koong; Douglas K Owens; Jeremy D. Goldhaber-Fiebert; Daniel T. Chang

BACKGROUND The role of surveillance studies in limited-stage diffuse large B-cell lymphoma (DLBCL) in the rituximab era has not been well defined. We sought to evaluate the use of imaging (computed tomography [CT] and positron emission tomography [PET]-CT) scans and lactate dehydrogenase (LDH) in surveillance of patients with stage I to II DLBCL. METHODS A retrospective analysis was performed of patients who received definitive treatment between 2000 and 2013. RESULTS One hundred sixty-two consecutive patients with stage I to II DLBCL were treated with chemotherapy +/- rituximab, radiation, or combined modality therapy. The 5-year rates of overall survival (OS) and freedom from progression (FFP) were 81.2% and 80.8%, respectively. Of the 162 patients, 124 (77%) were followed up with at least 1 surveillance PET scan beyond end-of-treatment scans; of those, 94 of 124 (76%) achieved a complete metabolic response on PET scan after completion of chemotherapy, and this was associated with superior FFP (P=.01, HR=0.3) and OS (P=.01, HR 0.3). Eighteen patients experienced relapse after initial response to therapy. Nine relapses were initially suspected by surveillance imaging studies (8 PET, 1 CT), and 9 were suspected clinically (5 by patient-reported symptoms and 4 by symptoms and physical examination). No relapses were detected by surveillance LDH. The median duration from initiation of treatment to relapse was 14.3 months among patients with relapses suspected by imaging, and 59.8 months among patients with relapses suspected clinically (P=.077). There was no significant difference in OS from date of first therapy or OS after relapse between patients whose relapse was suspected by imaging versus clinically. Thirteen of 18 patients underwent successful salvage therapy after relapse. CONCLUSIONS A complete response on PET scan immediately after initial chemotherapy is associated with superior FFP and OS in stage I to II DLBCL. The use of PET scans as posttreatment surveillance is not associated with a survival advantage. LDH is not a sensitive marker for relapse. Our results argue for limiting the use of posttreatment surveillance in patients with limited-stage DLBCL.


Oral Oncology | 2015

A prospective study of electronic quality of life assessment using tablet devices during and after treatment of head and neck cancers.

Erqi L. Pollom; Ellen Wang; Timothy Bui; Grant Ognibene; Rie von Eyben; Vasu Divi; John B. Sunwoo; Michael Kaplan; A. Dimitri Colevas; Quynh-Thu Le; Wendy Hara

Although stereotactic body radiotherapy (SBRT) or stereotactic ablative radiotherapy has become an established standard of care for the treatment of a variety of malignancies, our understanding of normal tissue dose tolerance with extreme hypofractionation remains immature. Since Timmerman initially proposed normal tissue dose constraints for SBRT in the 2008 issue of Seminars of Radiation Oncology, experience with SBRT has grown, and more long-term clinical outcome data have been reported. This article reviews the modern toxicity literature and provides updated clinically practical and useful recommendations of SBRT dose constraints for extracranial sites. We focus on the major organs of the thoracic and upper abdomen, specifically the liver and the lung.

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Albert C. Koong

University of Texas MD Anderson Cancer Center

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