Jonas A. De Souza
University of Chicago
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Featured researches published by Jonas A. De Souza.
Clinical Cancer Research | 2012
Jonas A. De Souza; Darren W. Davis; Yujian Zhang; Arun Khattri; Tanguy Y. Seiwert; Serdal Aktolga; Stuart J. Wong; Mark Kozloff; Sreenivasa Nattam; Mark W. Lingen; Rangesh Kunnavakkam; Kerstin M. Stenson; Elizabeth A. Blair; Jeffrey Bozeman; Janet Dancey; Everett E. Vokes; Ezra E.W. Cohen
Purpose: This study sought to determine the efficacy and safety profile of lapatinib in patients with recurrent/metastatic squamous cell carcinoma of the head and neck (SCCHN). Experimental Design: This phase II multiinstitutional study enrolled patients with recurrent/metastatic SCCHN into two cohorts: those without (arm A) and those with (arm B) before exposure to an epidermal growth factor receptor (EGFR) inhibitor. All subjects were treated with lapatinib 1,500 mg daily. Primary endpoints were response rate (arm A) and progression-free survival (PFS; arm B). The biologic effects of lapatinib on tumor growth and survival pathways were assessed in paired tumor biopsies obtained before and after therapy. Results: Forty-five patients were enrolled, 27 in arm A and 18 in arm B. Diarrhea was the most frequent toxicity occurring in 49% of patients. Seven patients experienced related grade 3 toxicity (3 fatigue, 2 hyponatremia, 1 vomiting, and 1 diarrhea). In an intent-to-treat analysis, no complete or partial responses were observed, and stable disease was the best response observed in 41% of arm A (median duration, 50 days, range, 34–159) and 17% of arm B subjects (median, 163 days, range, 135–195). Median PFS was 52 days in both arms. Median OS was 288 (95% CI, 62–374) and 155 (95% CI, 75–242) days for arms A and B, respectively. Correlative analyses revealed an absence of EGFR inhibition in tumor tissue. Conclusion: Lapatinib as a single agent in recurrent/metastatic SCCHN, although well tolerated, appears to be inactive in either EGFR inhibitor naive or refractory subjects. Clin Cancer Res; 18(8); 2336–43. ©2012 AACR.
Nature Reviews Clinical Oncology | 2013
Gilberto Lopes; Jonas A. De Souza; Carlos H. Barrios
Major breakthroughs have been realized in controlling cancer in the past five decades. However, for patients in low- and middle-income countries (LMICs), many of these advances are nothing but an aspiration and hope for the future. Indeed, the greatest challenge we face in oncology today is how to reconcile small, incremental and significant improvements in the management of cancer with the exponentially increasing costs of new treatments. Emerging economies are attempting to address this important issue of access to cancer medications. In this Review, we examine how LMICs are using generic and biosimilar drugs, expanding participation in clinical trials, implementing universal health-care schemes to pool resources, and using compulsory licensing schemes as well as increasing multiple-stakeholder public–private partnerships to increase access to cancer medications for their citizens. Any truly effective programme will require multiple stakeholder involvement—including governments, industry and civil society—to address the issue of access to medication. Only with the creation of a global entity to fight cancer that is supported by a global fund—for example, in the mould of the GAVI alliance and the International Finance Facility for Immunization—will we truly be able to improve cancer care in LMICs and drive down the high mortality rates in these regions.
Seminars in Oncology | 2011
Jonas A. De Souza; Olufunmilayo I. Olopade
The philosophy behind personalized medicine is that each patient has a unique biologic profile that should guide the choice of therapy, resulting in an improved treatment outcome, ideally with reduced toxicity. Thus, there has been increasing interest in identifying genetic variations that are predictive of a drugs efficacy or toxicity. Although it is one of the most effective drugs for treating breast cancer, tamoxifen is not effective in all estrogen receptor (ER)-positive breast cancer patients, and it is frequently associated with side effects, such as hot flashes. Relative resistance to tamoxifen treatment may be a result, in part, from impaired drug activation by cytochrome P450 2D6 (CYP2D6). Indeed, recent studies have identified allelic variations in CYP2D6 to be an important determinant of tamoxifens activity (and toxicity). This article will summarize the current information regarding the influence of the major genotypes and CYP2D6 inhibitors on tamoxifen metabolism, with a focus on its clinical utility and the current level of evidence for CYP2D6 genotyping of patients who are candidates for tamoxifen treatment.
Current Opinion in Oncology | 2011
Mariana Ba Ferreira; Jonas A. De Souza; Ezra E.W. Cohen
Purpose of review Head and neck squamous cell carcinoma (HNSCC) is the fifth most common cancer worldwide. Despite advances in treatment, the prognosis remains poor. HNSCC comprise a wide spectrum of neoplasms with different tumor biologies, prognosis and response to therapies. Current tumor classification is based on morphology and anatomic distribution, which leads to a homogeneous treatment for different diseases. Moreover, traditional diagnostic methods such as clinical assessment, histopathological examination, and imaging techniques are limited in their capacity to provide information on prognosis and decision making. Recent findings Molecular markers have increased the understanding of the pathogenesis of head and neck cancer because they give increasing insight into tumor biology, prognosis, and response to therapy. The practical application of these discoveries is beginning to assist greatly in the evaluation and treatment of HNSCC to achieve a more personalized and effective approach. Summary This article focuses on the molecular markers that have already been extensively studied such as epidermal growth factor receptor and human papillomavirus as well as those that offer potential for personalized therapy such as HIF-1 and ERCC-1. The ideal biomarker should be assayed accurately and easily, highly specific, and cost effective. Thus, a validation is required before their implementation into clinical guidelines.
Cancer immunology research | 2015
Rodney J. Taylor; Vassiliki Saloura; Ajay Jain; Olga Goloubeva; Stuart J. Wong; Shari Kronsberg; Madhavi Nagilla; Lorna Silpino; Jonas A. De Souza; Tanguy Y. Seiwert; Everett E. Vokes; Victoria M. Villaflor; Ezra E.W. Cohen
Taylor and colleagues studied patients with recurrent or metastatic squamous cell carcinoma of the head and neck treated with cetuximab and lenalidomide and report that enhanced ex vivo antibody-dependent cellular cytotoxicity and innate immunity best predicted clinical responses. We conducted in vitro studies and a clinical trial for patients with squamous cell carcinoma of the head and neck (SCCHN) to study the relationship between FcγRIIIa polymorphisms and antibody-dependent cellular cytotoxicity (ADCC). In vitro, FcγRIIIa genotype was correlated with ADCC and innate cytotoxicity using natural killer (NK) cells harvested from healthy donors. In the phase II study, patients with recurrent or metastatic SCCHN were treated with cetuximab (500 mg/m2 i.v. every 2 weeks) and lenalidomide (25 mg daily). FcγRIIIa genotype and ex vivo ADCC were correlated with clinical response, progression-free survival (PFS), and overall survival (OS). In vitro, healthy donors with a FcγRIIIa 158-V allele demonstrated more effective ADCC against two colon cancer cell lines HT29 and SW480, mean cytotoxicity: FF 16.1%, VF/VV 24.3% (P = 0.015) and FF 11.7%, VF/VV 21.0% (P = 0.008), respectively. We observed a linear relationship between ADCC response and innate cytotoxicity. In the phase II trial, 40 patients received cetuximab and lenalidomide with median PFS of 7.2 weeks and OS of 16.4 weeks. Thirty-six patients had FcγRIIIa genotype: VV (2), VF (20), and FF (14), and 25 patients had sufficient NK-cell yield to perform ex vivo ADCC. FcγRIIIa genotype was not associated with any clinical outcomes. Patients mounting ex vivo ADCC response had a higher likelihood of stable disease (P = 0.01) and showed a trend toward increased PFS: 14 weeks versus 6.8 weeks, respectively (P = 0.13). Enhanced ex vivo ADCC and innate immunity responses were more predictive of clinical response than FcγRIIIa and may offer a functional assay to select patients suitable for cetuximab therapy. Cancer Immunol Res; 3(5); 567–74. ©2015 AACR.
Journal of Medicine and The Person | 2013
Jonas A. De Souza; Yu-Ning Wong
Novel diagnostic and therapeutic options offer hope to cancer patients with both localized and advanced disease. However, many of these treatments are often costly and even well-insured patients can face high out-of-pocket costs. Families may also be at risk of financial distress due to lost wages and other treatment-related expenses. Research is needed to measure and characterize financial distress in cancer patients and understand how it affects their quality of life. In addition, health care providers need to be trained to counsel patients and their families so they can make patient-centered treatment decisions that reflect their preferences and values.
Value in Health | 2013
Kathy L. Schulman; Karina Berenson; Ya Chen Shih; K. Foley; Arijit Ganguli; Jonas A. De Souza; Nicholas A. Yaghmour; Alex Shteynshlyuger
OBJECTIVES The ISPOR Oncology Special Interest Group formed a working group at the end of 2010 to develop standards for conducting oncology health services research using secondary data. The first mission of the group was to develop a checklist focused on issues specific to selection of a sample of oncology patients using a secondary data source. METHODS A systematic review of the published literature from 2006 to 2010 was conducted to characterize the use of secondary data sources in oncology and inform the leadership of the working group prior to the construction of the checklist. A draft checklist was subsequently presented to the ISPOR membership in 2011 with subsequent feedback from the larger Oncology Special Interest Group also incorporated into the final checklist. RESULTS The checklist includes six elements: identification of the cancer to be studied, selection of an appropriate data source, evaluation of the applicability of published algorithms, development of custom algorithms (if needed), validation of the custom algorithm, and reporting and discussions of the ascertainment criteria. The checklist was intended to be applicable to various types of secondary data sources, including cancer registries, claims databases, electronic medical records, and others. CONCLUSIONS This checklist makes two important contributions to oncology health services research. First, it can assist decision makers and reviewers in evaluating the quality of studies using secondary data. Second, it highlights methodological issues to be considered when researchers are constructing a study cohort from a secondary data source.
Biology of Blood and Marrow Transplantation | 2009
Jonas A. De Souza; Rima M. Saliba; Poliana A. Patah; Gabriela Rondon; Rachel Ribeiro; Leandro de Padua Silva; Muzaffar H. Qazilbash; Chitra Hosing; Uday Popat; Yvonne A Efebera; Richard E. Champlin; Marcos de Lima
Nonrelapse mortality (NRM) after reduced-intensity allogeneic transplants is likely to be influenced by abnormalities in renal function. We studied 141 patients diagnosed with acute myelogenous leukemia (AML) (n = 131) or high-risk myelodysplastic syndrome (MDS) (n = 10) who underwent allogeneic transplantation with fludarabine (Flu)/melphalan (Mel)-based regimens and hypothesized that moderate to mild renal function impairment increases NRM in this setting. Flu dose consisted of 25-30 mg/m(2) for 4 days and Mel dose was 100-180 mg/m(2). Donors were HLA-compatible siblings (n = 69) and matched unrelated donors (n = 72). Disease status at transplantation was complete remission (n = 56, 40%) or active disease (n = 85, 60%). The influence of the estimated glomerular filtration rate (GFR) measured before transplantation on outcomes was analyzed. GFR was estimated by both the Cockcroft-Gault (CG) and the modified diet in renal disease (MDRD) equations, using the creatinine value obtained prior to starting chemotherapy. Evaluated outcomes were overall survival (OS), NRM, and treatment-related mortality (TRM) at day 100 and 1-year posttransplantation. Median age was 55 years (range: 21-74 years); 59% of the patients were male. Estimated GFR by CG was > or =90 for 45 (32%), 60-89 for 78 (55%), and <60 for 18 (13%) patients. When estimated by MDRD, GFR was > or =90 for 65 (46%), 60-89 from 66 (47%), and <60 for 10 (7%) patients. The majority of patients by both estimations had a GFR between 60 and 89 (n = 78 by CG and n = 66 by MDRD) with no difference in the evaluated outcomes between this group and the subgroup of patients with a GFR <60 (P > .05). There were no differences in OS and NRM at day 100 and 1-year posttransplantation in the 3 groups by any GFR estimation method. In conclusion, a mild to moderate decrease in GFR was not associated with an increase in NRM.
Value in Health | 2016
Sheetal Mehta Kircher; Caitlin R. Meeker; Halla Sayed Nimeiri; Daniel M. Geynisman; S. Yousuf Zafar; Veena Shankaran; Jonas A. De Souza; Yu Ning Wong
Over the last decade, there has been increased development and use of oral anticancer medications, which sometimes leads to high cost sharing for patients. Drug parity laws require insurance plans to cover oral anticancer medications with the same cost sharing as intravenous/injected chemotherapy or have a capped limit on out-of-pocket costs. There are currently 36 enacted state laws (plus the District of Columbia) addressing drug parity, but no federal laws. In this policy perspective piece, we discuss the history, opportunities, and limitations of drug parity laws in oncology. We also discuss the implications of provisions of the Affordable Care Act and other proposed policy reforms on financing oral chemotherapy.
The Journal of community and supportive oncology | 2016
Jeremy O'Connor; Sheetal Mehta Kircher; Jonas A. De Souza
The cost of cancer care is increasing, with important implications for the delivery of high-quality, patent-centered care. In the clinical setting, patents and physicians express a desire to discuss out-of-pocket costs. Nevertheless, both groups feel inadequately prepared to participate in these discussions, and perhaps not surprisingly, the integration of these discussions into clinical practice seems to be the exception rather than the rule. The resulting neglect of financial issues has the potential to cause unnecessary suffering for oncology patents. In this paper, we review the most relevant literature on financial toxicity in cancer care. In addition, we discuss potential predictors of financial toxicity, and the recent development of instruments to help clinicians and researchers quantify financial burden.