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Dive into the research topics where Michelle Byrtek is active.

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Featured researches published by Michelle Byrtek.


Journal of Clinical Oncology | 2015

Early Relapse of Follicular Lymphoma After Rituximab Plus Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone Defines Patients at High Risk for Death: An Analysis From the National LymphoCare Study

Carla Casulo; Michelle Byrtek; Keith L Dawson; Xiaolei Zhou; Charles M. Farber; Christopher R. Flowers; John D. Hainsworth; Matthew J. Maurer; James R. Cerhan; Brian K. Link; Andrew D. Zelenetz; Jonathan W. Friedberg

PURPOSE Twenty percent of patients with follicular lymphoma (FL) experience progression of disease (POD) within 2 years of initial chemoimmunotherapy. We analyzed data from the National LymphoCare Study to identify whether prognostic FL factors are associated with early POD and whether patients with early POD are at high risk for death. PATIENTS AND METHODS In total, 588 patients with stage 2 to 4 FL received first-line rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Two groups were defined: patients with early POD 2 years or less after diagnosis and those without POD within 2 years, the reference group. An independent validation set, 147 patients with FL who received first-line R-CHOP, was analyzed for reproducibility. RESULTS Of 588 patients, 19% (n = 110) had early POD, 71% (n = 420) were in the reference group, 8% (n = 46) were lost to follow-up, and 2% (n = 12) died without POD less than 2 years after diagnosis. Five-year overall survival was lower in the early-POD group than in the reference group (50% v 90%). This trend was maintained after we adjusted for FL International Prognostic Index (hazard ratio, 6.44; 95% CI, 4.33 to 9.58). Results were similar for the validation set (FL International Prognostic Index-adjusted hazard ratio, 19.8). CONCLUSION In patients with FL who received first-line R-CHOP, POD within 2 years after diagnosis was associated with poor outcomes and should be further validated as a standard end point of chemoimmunotherapy trials of untreated FL. This high-risk FL population warrants further study in directed prospective clinical trials.


Journal of Clinical Oncology | 2012

Effectiveness of First-Line Management Strategies for Stage I Follicular Lymphoma: Analysis of the National LymphoCare Study

Jonathan W. Friedberg; Michelle Byrtek; Brian K. Link; Christopher R. Flowers; Michael D. Taylor; John D. Hainsworth; James R. Cerhan; Andrew D. Zelenetz; Jamie Hirata; Thomas P. Miller

PURPOSE The optimal management of stage I follicular lymphoma, according to consensus guidelines, is based on uncontrolled experiences of select institutions. Diverse treatment approaches are used despite guidelines that recommend radiation therapy (XRT). PATIENTS AND METHODS We analyzed outcomes of patients with stage I follicular lymphoma enrolled onto the National LymphoCare database. RESULTS Of 471 patients with stage I follicular lymphoma, 206 patients underwent rigorous staging as defined by both a bone marrow aspirate and biopsy and an imaging study (a computed tomography [CT] scan of the whole body, a positron emission tomography [PET]/CT scan, or both). Rigorously staged patients had superior progression-free survival (PFS) compared with nonrigorously staged patients (hazard ratio [HR], 0.63). Treatments given to rigorously staged patients were rituximab/chemotherapy (R-chemo; 28%), XRT (27%), observation (17%), systemic therapy + XRT (13%), rituximab monotherapy (12%), and other (3%). With a median follow-up of 57 months for PFS, there were 44 progression events (in 21% of patients) for rigorously staged patients. For these patients, PFS was significantly improved with either R-chemo or systemic therapy + XRT compared with patients receiving XRT alone after adjustment for histology, LDH, and the presence of B symptoms. There were no differences in overall survival. CONCLUSION In this largest, prospectively enrolled group of patients with stage I follicular lymphoma, variable treatment approaches resulted in similar excellent outcomes, which challenges the paradigm that XRT should be standard for this presentation.


Blood | 2015

Outcomes of transformed follicular lymphoma in the modern era: a report from the National LymphoCare Study (NLCS).

Nina D. Wagner-Johnston; Brian K. Link; Michelle Byrtek; Keith L Dawson; John D. Hainsworth; Christopher R. Flowers; Jonathan W. Friedberg; Nancy L. Bartlett

We assessed the incidence, prognostic features, and outcomes associated with transformation of follicular lymphoma (FL) among 2652 evaluable patients prospectively enrolled in the National LymphoCare Study. At a median follow-up of 6.8 years, 379/2652 (14.3%) patients transformed following the initial FL diagnosis, including 147 pathologically confirmed and 232 clinically suspected cases. Eastern Cancer Oncology Group performance status >1, extranodal sites >1, elevated lactate dehydrogenase, and B symptoms at diagnosis were associated with transformation risk. Relative to observation, patients initiating treatment at diagnosis had a reduced risk of transformation (hazard ratio [HR], 0.58; 95% confidence interval [CI], 0.46-0.75). The risk of transformation was similar in patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone compared with rituximab, cyclophosphamide, vincristine, and prednisone (adjusted HR, 0.94; 95% CI, 0.62-1.42). Maintenance rituximab was associated with reduced transformation risk (HR, 0.67; 95% CI, 0.46-0.97). Five-year survival from diagnosis was significantly worse for patients with vs without transformation (75%, 95% CI, 70-79 vs 85%, 95% CI, 83-86). The median overall survival post-transformation was 5 years. Forty-seven patients with evidence of transformation at the time of diagnosis shared similar prognostic factors and survival rates to those without transformation. Improved outcomes for transformation in the modern era are suggested by this observational study. This trial is registered at www.clinicaltrials.gov as #NCT00097565.


Journal of Clinical Oncology | 2016

Randomized Open-Label Phase II Trial of Apitolisib (GDC-0980), a Novel Inhibitor of the PI3K/Mammalian Target of Rapamycin Pathway, Versus Everolimus in Patients With Metastatic Renal Cell Carcinoma

Thomas Powles; Mark R. Lackner; S. Oudard; B. Escudier; Christy Ralph; Janet E. Brown; Robert E. Hawkins; Daniel Castellano; Brian I. Rini; Michael Staehler; Alain Ravaud; Wei Lin; Bridget O’Keeffe; Yulei Wang; Shan Lu; Jill M. Spoerke; Ling-Yuh Huw; Michelle Byrtek; Rui Zhu; Joseph A. Ware; Robert J. Motzer

PURPOSE To the best of our knowledge, this study is the first to compare dual inhibition of PI3K/mammalian target of rapamycin (mTOR) by apitolisib (GDC-0980) against single inhibition of mTORC1 by everolimus in metastatic renal cell carcinoma (mRCC). PATIENTS AND METHODS Patients with clear-cell mRCC who progressed on or after vascular endothelial growth factor-targeted therapy were randomly assigned to apitolisib 40 mg once per day or to everolimus 10 mg once per day. End points included progression-free survival, safety, overall survival, and objective response rate. Biomarker assessments were conducted. RESULTS Eighty-five patients were randomly assigned. After 67 events, stratified analysis revealed that median progression-free survival was significantly shorter for apitolisib than for everolimus (3.7 v 6.1 months; hazard ratio, 2.12 [95% CI, 1.23 to 3.63; P < .01]); apitolisib was not favored in any stratification subgroup. Median overall survival was not significantly different but trended in favor of everolimus (16.5 v 22.8 months; hazard ratio, 1.77 [95% CI, 0.97 to 3.24; P = .06]). The objective response rate was 7.1% for apitolisib and 11.6% for everolimus. Patients administered apitolisib with a greater incidence of grade 3 to 4 adverse events were more likely to discontinue treatment (31% v 12% for everolimus). No drug-related deaths were observed. Apitolisib in comparison with everolimus was associated with substantially more high-grade hyperglycemia (40% v 9%) and rash (24% v 2%). Apitolisib pharmacokinetics suggested a relationship between exposure, and rash and hyperglycemia. Retrospective biomarker analyses revealed a relationship between VHL mutation status and outcome with everolimus but not with apitolisib. High hypoxia-inducible factor 1α protein expression was associated with better outcome in both arms. CONCLUSION This study demonstrated that dual PI3K/mTOR inhibition by apitolisib was less effective than was everolimus in mRCC, likely because full blockade of PI3K/mTOR signaling resulted in multiple on-target adverse events. VHL mutation and hypoxia-inducible factor 1α expression may be predictive of an mTOR inhibitor benefit, although prospective validation is required.


Annals of Oncology | 2013

Examination of the follicular lymphoma international prognostic index (FLIPI) in the National LymphoCare study (NLCS): a prospective US patient cohort treated predominantly in community practices

A. K. Nooka; Chadi Nabhan; Xiaolei Zhou; Michael D. Taylor; Michelle Byrtek; Thomas P. Miller; Jonathan W. Friedberg; Andrew D. Zelenetz; Brian K. Link; James R. Cerhan; Hildy Dillon; Rajni Sinha; P. J. Shenoy; D. Levy; Keith L Dawson; Jamie Hirata; Christopher R. Flowers

BACKGROUND Because follicular lymphoma (FL) patients have heterogeneous outcomes, the FL international prognostic index (FLIPI) was developed to risk-stratify patients and to predict survival. However, limited data exist regarding the role of FLIPI in the era of routine first-line rituximab (R) and R-chemotherapy regimens and in the setting of community oncology practices. PATIENTS AND METHODS We evaluated the outcome data from the National LymphoCare Study (NLCS), a prospective, observational cohort study, which collects data on patients with FL in the United States (US) community practices. RESULTS Among 1068 male and 1124 female patients with FLIPI data, most were treated in US community practices (79%); 35% were FLIPI good risk, 30% intermediate risk, and 35% poor risk. FLIPI risk groups were significant predictors of overall survival (OS) and progression-free survival (PFS) for patients who undergo watchful waiting (WW), and those who receive non-R-containing regimens, R-alone, and R-chemotherapy combinations. CONCLUSIONS In the setting of contemporary practice with routine R use, stratifying patients into good, intermediate, and poor FLIPI risk groups predicts distinct outcomes in terms of OS and PFS. FLIPI remains an important prognostic index in the R era and should be used in clinical practices to support discussions about prognosis.BACKGROUND Because follicular lymphoma (FL) patients have heterogeneous outcomes, the FL international prognostic index (FLIPI) was developed to risk-stratify patients and to predict survival. However, limited data exist regarding the role of FLIPI in the era of routine first-line rituximab (R) and R-chemotherapy regimens and in the setting of community oncology practices. PATIENTS AND METHODS We evaluated the outcome data from the National LymphoCare Study (NLCS), a prospective, observational cohort study, which collects data on patients with FL in the United States (US) community practices. RESULTS Among 1068 male and 1124 female patients with FLIPI data, most were treated in US community practices (79%); 35% were FLIPI good risk, 30% intermediate risk, and 35% poor risk. FLIPI risk groups were significant predictors of overall survival (OS) and progression-free survival (PFS) for patients who undergo watchful waiting (WW), and those who receive non-R-containing regimens, R-alone, and R-chemotherapy combinations. CONCLUSIONS In the setting of contemporary practice with routine R use, stratifying patients into good, intermediate, and poor FLIPI risk groups predicts distinct outcomes in terms of OS and PFS. FLIPI remains an important prognostic index in the R era and should be used in clinical practices to support discussions about prognosis.


Cancer | 2012

Racial differences in presentation and management of follicular non-Hodgkin lymphoma in the United States: Report from the National LymphoCare Study

Chadi Nabhan; Michelle Byrtek; Michael D. Taylor; Jonathan W. Friedberg; James R. Cerhan; John D. Hainsworth; Thomas P. Miller; Jamie Hirata; Brian K. Link; Christopher R. Flowers

Racial differences in follicular lymphoma (FL) in the United States have not been investigated.


Cancer | 2014

The use and effectiveness of rituximab maintenance in patients with follicular lymphoma diagnosed between 2004 and 2007 in the United States.

Loretta J. Nastoupil; Rajni Sinha; Michelle Byrtek; Xiaolei Zhou; Michael D. Taylor; Jonathan W. Friedberg; Brian K. Link; James R. Cerhan; Keith L Dawson; Christopher R. Flowers

The authors examined the “real‐world” effectiveness of rituximab (R) maintenance therapy (R‐maintenance) compared with observation after R‐based induction therapy in patients with previously untreated follicular lymphoma (FL) in the United States.


Leukemia & Lymphoma | 2015

Comparison of the effectiveness of frontline chemoimmunotherapy regimens for follicular lymphoma used in the United States

Loretta J. Nastoupil; Rajni Sinha; Michelle Byrtek; Ryan Ziemiecki; Michael D. Taylor; Jonathan W. Friedberg; Jean L. Koff; Brian K. Link; James R. Cerhan; Keith L Dawson; Christopher R. Flowers

Abstract To compare the effectiveness of frontline rituximab-chemotherapy regimens in clinical practice, we examined outcomes for patients with low-grade, stage III/IV follicular lymphoma receiving rituximab (R) with cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP), R with cyclophosphamide, vincristine and prednisone (R-CVP) or R with a fludarabine-based regimen (R-Flu) as frontline therapy. In total, 611 patients meeting these criteria were identified in the National LymphoCare Study: 47% receiving R-CHOP (n = 287), 31% receiving R-CVP (n = 187) and 22% receiving R-Flu (n = 137). Overall response rates were high (R-CVP 87%, R-CHOP 93%, R-Flu 94%; p = 0.017). Median follow-up was 7.4 years. R-CVP was associated with lower 5-year overall survival (R-CVP 76%, R-CHOP 86%, R-Flu 86%; p = 0.021) and progression-free survival (R-CVP 49%, R-CHOP 58%, R-Flu 64%; p = 0.029). There were no significant differences in survival in Cox models adjusted for baseline clinical factors, practice region/setting and post-treatment R maintenance/observation.


British Journal of Haematology | 2016

Outcomes following watchful waiting for stage II-IV follicular lymphoma patients in the modern era

Loretta J. Nastoupil; Rajni Sinha; Michelle Byrtek; Ryan Ziemiecki; Xiaolei Zhou; Michael D. Taylor; Jonathan W. Friedberg; Brian K. Link; James R. Cerhan; Keith L Dawson; Christopher R. Flowers

To examine the effectiveness of an initial management strategy of watchful waiting for follicular lymphoma (FL) in clinical practice, we compared outcomes for patients diagnosed 2004–2007 in the United States initially managed with watchful waiting with outcomes following initial rituximab monotherapy and chemoimmunotherapy. In total, 1754 stage II–IV patients in the National LymphoCare Study underwent watchful waiting (n = 386), rituximab monotherapy (n = 296) or rituximab plus chemotherapy (n = 1072) as initial management strategy. Female patients and those who received treatment in the Northeast or in an academic setting more commonly underwent watchful waiting versus initial chemoimmunotherapy; whereas patients with grade 3 histology, anaemia, elevated lactate dehydrogenase, extranodal involvement, B symptoms or performance status ≥1 more commonly received chemoimmunotherapy. Although time to new treatment and progression‐free survival following first‐ and second‐line therapy were improved with chemoimmunotherapy, and time to chemotherapy was improved with rituximab monotherapy, there were no differences in overall survival between watchful waiting and chemoimmunotherapy or rituximab monotherapy. With 8‐year overall survival estimates of 74%, initial management with watchful waiting in the context of sequential therapy remains a viable option for FL patients in the modern era. This trial was registered at www.clinicaltrials.gov (NCT00097565).


Cancer | 2013

Patterns of delivery of chemoimmunotherapy to patients with follicular lymphoma in the United States: results of the National LymphoCare Study.

Peter Martin; Michelle Byrtek; Keith L Dawson; Ryan Ziemiecki; Jonathan W. Friedberg; James R. Cerhan; Christopher R. Flowers; Brian K. Link

Drug choice and delivered dose of treatment potentially influence outcome in patients treated for follicular lymphoma (FL). Historically, observational studies have evaluated drug choice. The National LymphoCare Study (NLCS) is a prospective, observational study of patients with FL who were enrolled at academic and community practice sites in the United States between 2004 and 2007. In the current study, the authors report on measures of delivered dose and its impact on outcomes for the most common first‐line regimens.

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Jonathan W. Friedberg

Memorial Sloan Kettering Cancer Center

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Andrew D. Zelenetz

Memorial Sloan Kettering Cancer Center

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John D. Hainsworth

Sarah Cannon Research Institute

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