Keith L Dawson
Genentech
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Publication
Featured researches published by Keith L Dawson.
Journal of Clinical Oncology | 2015
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.
Blood | 2015
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.
Annals of Oncology | 2013
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 | 2014
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
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
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
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.
British Journal of Haematology | 2015
Chadi Nabhan; Michelle Byrtek; Ashish Rai; Keith L Dawson; Xiaolei Zhou; Brian K. Link; Jonathan W. Friedberg; Andrew D. Zelenetz; Matthew J. Maurer; James R. Cerhan; Christopher R. Flowers
Data from the National LymphoCare Study (a prospective, multicentre registry that enrolled follicular lymphoma (FL) patients from 2004 to 2007) were used to determine disease characteristics, treatment patterns, outcomes and prognosis for elderly FL (eFL) patients. Of 2650 FL patients, 209 (8%) were aged >80 years; these eFL patients more commonly had grade 3 disease, less frequently received chemoimmunotherapy and anthracyclines, and had lower response rates when compared to younger patients. With a median follow‐up of 6.9 years, 5‐year overall survival (OS) for eFL patients was 59%; 38% of deaths were lymphoma‐related. No treatment produced superior OS among eFL patients. In multivariate Cox models, anaemia, B‐symptoms and male sex predicted worse OS (P < 0·01); a prognostic index of these factors (0, 1 or ≥2 present) predicted OS [hazard ratio (95% CI): ≥2 vs. 0, 4·72 (2·38–9·33); 1 vs. 0, 2·63 (1·39–4·98)], with a higher concordance index (0·63) versus the Follicular Lymphoma International Prognostic Index (0·55). The index was validated in an independent cohort. In the largest prospective US‐based eFL cohort, no optimal therapy was identified and nearly 40% of deaths were lymphoma‐related, representing baseline outcomes in the modern era.
Annals of Oncology | 2015
Carla Casulo; Bann-mo Day; Keith L Dawson; Xiaolei Zhou; Christopher R. Flowers; Charles M. Farber; John D. Hainsworth; James R. Cerhan; Brian K. Link; Andrew D. Zelenetz; Jonathan W. Friedberg
BACKGROUND Follicular lymphoma (FL) is the most common indolent non-Hodgkin lymphoma, with median age at diagnosis in the seventh decade. FL in young adults (YAs), defined as diagnosis at ≤40 years, is uncommon. No standard approaches exist guiding the treatment of YA FL, and little is known about their disease characteristics and outcomes. To gain further insights into YA FL, we analyzed the National LymphoCare Study (NLCS) to describe characteristics, initial treatments, and outcomes in this population versus patients aged >40 years. PATIENTS AND METHODS Using the NLCS database, we stratified FL patients by age: 18-40 (YA), 41-60, 61-70, 71-80, and >80 years. Survival probability was estimated using Kaplan-Meier methodology. We examined associations between age and survival using hazard ratios and 95% confidence intervals (CIs) from multivariable Cox models. RESULTS Of 2652 eligible FL patients in the NLCS, 164 (6%) were YAs. Of YA patients, 69% had advanced disease, 80% had low-grade histology, and 50% had good-risk disease according to the Follicular Lymphoma International Prognostic Index (FLIPI). Nineteen percent underwent observation, 12% received rituximab monotherapy, and 46% received chemoimmunotherapy [in 59% of these: R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone)]. With a median follow-up of 8 years, overall survival (OS) at 2, 5, and 8 years was 98% (95% CI 93-99), 94% (95% CI 89-97), and 90% (95% CI 83-94), respectively. Median progression-free survival (PFS) was 7.3 years (95% CI 5.6-not reached). CONCLUSIONS In one of the largest cohorts of YA FL patients treated in the rituximab era, disease characteristics and outcomes were similar to patients aged 41-60 years, with favorable OS and PFS in YAs. Longer-term outcomes and YA-specific survivorship concerns should be considered when defining management. These data may not support the need for more aggressive therapies in YA FL. CLINICAL TRIAL NUMBER Roche/Genentech ML01377 (U2963n).
Leukemia & Lymphoma | 2017
Ida Wong-Sefidan; Michelle Byrtek; Xiaolei Zhou; Jonathan W. Friedberg; Christopher R. Flowers; Andrew D. Zelenetz; Keith L Dawson; Erin Reid
Abstract Positron emission tomography (PET) after induction therapy in follicular lymphoma (FL) is predictive of survival in clinical trials. We describe use of PET and computed tomography (CT) after rituximab-based induction therapy in FL patients followed by the National LymphoCare Study and explore the association between imaging response assessment and survival. Among 1289 patients, imaging consisted of: PET ± CT (35%), CT alone (42%), other/no imaging (24%). Median follow-up was 7.6 years. In unadjusted analyses, positive PET ± CT and CT were prognostic of inferior OS (HR 1.78; 95% CI: 1.16–2.72 and HR 1.61, 95% CI: 1.13–2.29, respectively) and PFS (HR 1.63, 95% CI: 1.21–2.20 and HR 1.45, 95% CI: 1.12–1.89, respectively). Adjusting for FL International Prognostic Index, PET remained predictive of OS (HR 1.54, 95% CI: 1.01–2.36) and PFS (HR 1.54, 95% CI: 1.14–2.07). Residual disease via PET in FL is prognostic of survival in clinical practice.