Person: Yeap, Beow
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Publication Donor Bone Marrow-Derived T Cells Inhibit GVHD Induced by Donor Lymphocyte Infusion in Established Mixed Allogeneic Hematopoietic Chimeras
(Public Library of Science, 2012) Wang, Hui; Yang, Yanping; Wang, Guanjun; Wang, Shumei; Yeap, Beow; Sykes, Megan; Yang, Yong-GuangDelayed administration of donor lymphocyte infusion (DLI) to established mixed chimeras has been shown to achieve anti-tumor responses without graft-vs.-host disease (GVHD). Herein we show that de novo donor BM-derived T cells that are tolerant of the recipients are important in preventing GVHD in mixed chimeras receiving delayed DLI. Mixed chimeras lacking donor BM-derived T cells developed significantly more severe GVHD than those with donor BM-derived T cells after DLI, even though both groups had comparable levels of total T cells at the time of DLI. Post-DLI depletion of donor BM-derived T cells in mixed chimeras, as late as 20 days after DLI, also provoked severe GVHD. Although both CD4 and CD8 T cells contributed to the protection, the latter were significantly more effective, suggesting that inhibition of GVHD was not mainly mediated by CD4 regulatory T cells. The lack of donor BM-derived T cells was associated with markedly increased accumulation of DLI-derived alloreactive T cells in parenchymal GVHD target tissues. Thus, donor BM-derived T cells are an important factor in determining the risk of GVHD and therefore, offer a potential therapeutic target for preventing and ameliorating GVHD in the setting of delayed DLI in established mixed chimeras.
Publication A prospective feasibility study of respiratory-gated proton beam therapy for liver tumors
(Elsevier BV, 2014) Hong, Theodore; Delaney, Thomas; Mamon, Harvey; Willett, Christopher G.; Yeap, Beow; Niemierko, Andrzej; Wolfgang, John; Lu, Hsiao-Ming; Adams, Judith; Weyman, Elizabeth A.; Arellano, Ronald; Blaszkowsky, Lawrence; Allen, Jill; Tanabe, Kenneth; Ryan, David; Zhu, AndrewPurpose
To evaluate the feasibility of a respiratory-gated proton beam therapy for liver tumors.
Materials and Methods
Fifteen patients were enrolled on a prospective IRB-approved protocol. Eligibility criteria included Childs-Pugh A/B cirrhosis, unresectablebiopsy-proven hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), or metastatic disease (solid tumors only), 1-3 lesions, and tumor size of ≤6 cm. Patients received 15 fractions to a total dose of 45-75 GyE using respiratory-gated proton beam therapy. Gating was performed with an external respiratory position monitoring (RPM) based system.
Results
Of the15 patients enrolled on this clinical trial, 11 had HCC, 3 had ICC, and 1had metastasis from another primary. Ten patients had a single lesion, 3 patients had 2 lesions, and 2 patients 3 lesions. Toxicities were: Gr 3 bilirubinemia- 2, Gr 3 gastrointestinal bleed- 1, and Gr 5 stomach perforation-1. One patient had a marginal recurrence, 3 had hepatic recurrences elsewhere in the liver, and 2 had extrahepatic recurrence. With a median follow-up for survivors of 69 months, 1-yr, 2-yr, 3-yr OS is 53%, 40%, and 33% respectively. PFS is 40%,33% and 27% at 1, 2, and 3 years, respectively.
Conclusion
Respiratory-gated proton beam therapy for liver tumors is feasible. Phase II studies for primary liver tumors and metastatic tumorsare underway.
Publication Clinical, Pathologic, and Biologic Features Associated with BRAF Mutations in Non-Small Cell Lung Cancer
(American Association for Cancer Research (AACR), 2013) Cardarella, S.; Ogino, Atsuko; Nishino, Michiya; Butaney, M.; Shen, Jeanne; Lydon, C.; Yeap, Beow; Sholl, Lynette; Johnson, Bruce; Janne, PasiPurpose
BRAF mutations are found in a subset of non-small cell lung cancers (NSCLCs). We examined the clinical characteristics and treatment outcomes of patients with NSCLC harboring BRAF mutations.
Experimental Design
Using DNA sequencing, we successfully screened 883 NSCLC patients for BRAF mutations between 7/1/09 and 7/16/12. Baseline characteristics and treatment outcomes were compared between patients with and without BRAF mutations. Wild type controls consisted of NSCLC patients without a somatic alteration in BRAF, KRAS, EGFR, and ALK. In vitro studies assessed the biological properties of selected non-V600E BRAF mutations identified from NSCLC patients.
Results
Of 883 tumors screened, 36 (4%) harbored BRAF mutations (V600E: 18; non-V600E: 18) and 257 were wild type for BRAF, EGFR, KRAS, and ALK negative. Twenty-nine of the 36 BRAF mutant patients were smokers. There were no distinguishing clinical features between BRAF mutant and wild type patients. Advanced NSCLC patients with BRAF mutations and wild type tumors showed similar response rates and progression-free survival (PFS) to platinum-based combination chemotherapy and no difference in overall survival. Within the BRAF cohort, patients with V600E mutated tumors had a shorter PFS to platinum-based chemotherapy compared to those with non-V600E mutations, although this did not reach statistical significance (4.1 versus 8.9 months; P=0.297). We identified five BRAF mutations not previously reported in NSCLC; two of the five were associated with increased BRAF kinase activity.
Conclusions
BRAF mutations occur in 4% of NSCLCs and half are non-V600E. Prospective trials are ongoing to validate BRAF as a therapeutic target in NSCLC.
Publication Lung Adenocarcinoma with EGFR Amplification Has Distinct Clinicopathologic and Molecular Features in Never-Smokers
(American Association for Cancer Research (AACR), 2009) Sholl, Lynette; Yeap, Beow; Iafrate, Anthony; Holmes-Tisch, A. J.; Chou, Y.-P.; Wu, Ming-Tsang; Goan, Y.-G.; Su, Li; Benedettini, E.; Yu, J.; Loda, Massimo; Janne, Pasi; Christiani, David; Chirieac, LucianIn a subset of lung adenocarcinomas the epidermal growth factor receptor (EGFR) is activated by kinase domain mutations and/or gene amplification, but the interaction between the two types of abnormalities is complex and unclear. We selected to study 99 consecutive never-smoking women of East Asian origin with lung adenocarcinomas that were characterized by histologic subtype. We analyzed EGFR mutations by PCR-capillary sequencing, EGFR copy number abnormalities by fluorescence and chromogenic in situ hybridization and quantitative PCR, and EGFR expression by immunohistochemistry with both specific antibodies against exon 19 deletion-mutated EGFR and total EGFR. We compared molecular and clinicopathologic features with disease-free survival. Lung adenocarcinomas with EGFR amplification had significantly more EGFR exon 19 deletion mutations than adenocarcinomas with disomy, low and high polysomy (100% v 54%, P=0.009). EGFR amplification occurred invariably on the mutated and not the wildtype allele (median mutated:wildtype ratios 14.0 v .33, P=0.003), was associated with solid histology (P=0.008), and advanced clinical stage (P=0.009). EGFR amplification was focally distributed in lung cancer specimens, mostly in regions with solid histology. Patients with EGFR amplification had a significantly worse outcome in univariate analysis (median disease-free survival 16 v 31 months, P=0.01) and when adjusted for stage (P=0.027). Lung adenocarcinomas with EGFR amplification have a unique association with exon 19 deletion mutations and demonstrate distinct clinicopathologic features associated with a significantly worsened prognosis. In these cases, EGFR amplification is heterogeneously distributed, mostly in areas with a solid histology.
Publication Sox2 Protein Expression is an Independent Poor Prognostic Indicator in Stage I Lung Adenocarcinoma
(Ovid Technologies (Wolters Kluwer Health), 2010) Sholl, Lynette; Barletta, Justine; Yeap, Beow; Chirieac, Lucian; Hornick, JasonMany patients with stage I non-small cell lung carcinoma will develop recurrence following surgical excision. Sox2 is a marker of embryonic stem cell pluripotency that is associated with aggressive tumor behavior and is expressed in a subset of lung adenocarcinomas. We hypothesized that Sox2 expression may provide prognostic information in early stage lung adenocarcinomas. We evaluated formalin-fixed paraffin embedded tissue from 104 stage I lung adenocarcinomas resected between 1997 and 2000. Sox2 expression was analyzed by immunohistochemistry and compared to clinicopathologic features, time-to-progression (TTP) and overall survival (OS). Sox2 expression was detected in 50% of cases and was more frequent in tumors from older and male patients but not significantly associated with smoking status, tumor stage, grade, or histologic subtype. Compared to Sox2-negative tumors, Sox2 expression predicted a shorter TTP (49% versus 82% at 5 years; P = 0.0006) and shorter OS (54% versus 79% at 5 years; P = 0.004). By multivariate analysis, Sox2 expression predicted a greater risk of progression among men (hazard ratio [HR] 5.6; 95% CI 2.3 to 13.8) and women (HR 2.1; 95% CI 0.8 to 5.7). Sox2 expression was associated with significantly shorter OS among men (HR 2.5; 95% CI 1.2 to 5.1), but not in women. Sox2 appears to be an independent predictor of poor outcome in stage I lung adenocarcinomas and may help stratify patients at increased risk for recurrence.
Publication EGFRMutation Is a Better Predictor of Response to Tyrosine Kinase Inhibitors in Non–Small Cell Lung Carcinoma Than FISH, CISH, and Immunohistochemistry
(Oxford University Press (OUP), 2010) Sholl, Lynette; Xiao, Yun; Joshi, Victoria; Yeap, Beow; Cioffredi, Leigh-Anne; Jackman, David M; Lee, Charles; Janne, Pasi; Lindeman, NealAbout 10% of patients with non–small cell lung carcinoma (NSCLC) respond to epidermal growth factor receptor (EGFR)-targeted tyrosine kinase inhibitors (TKIs). More than 75% of “responders” have activating mutations in EGFR. However, mutation analysis is not widely available, and proposed alternatives (in situ hybridization and immunohistochemical analysis) have shown inconsistent associations with outcome. Fluorescence in situ hybridization (FISH), chromogenic in situ hybridization (CISH), immunohistochemical analysis, and DNA sequencing were compared in this study of 40 NSCLC samples from TKI-treated patients. Response rates were 12 of 19 in EGFR-mutant vs 1 of 20 EGFR wild-type tumors (P = .0001), 7 of 19 FISH+ vs 4 of 17 FISH– tumors (not significant [NS]), 5 of 16 CISH+ vs 6 of 21 CISH– tumors (NS), and 3 of 9 immunohistochemically positive vs 7 of 22 immunohistochemically negative tumors (NS). EGFR mutation was associated with improved progression-free survival (P = .0004). Increased copy number (FISH or CISH) and protein expression (immunohistochemical) did not independently predict outcome. Thus, EGFR sequence analysis was the only method useful for predicting response and progression-free survival following TKI therapy in NSCLC.
Publication Aggressive therapy for patients with non-small cell lung carcinoma and synchronous brain-only oligometastatic disease is associated with long-term survival
(Elsevier BV, 2014) Gray, Phillip; Mak, Raymond; Yeap, Beow; Cryer, Sarah K.; Pinnell, Nancy E.; Christianson, Laura W.; Sher, David J.; Arvold, Nils; Baldini, Elizabeth; Chen, Aileen; Kozono, David; Swanson, Scott; Jackman, David M; Alexander, BrianObjectives: Optimal therapy for patients with non-small cell lung carcinoma (NSCLC) presenting with synchronous brain-only oligometastases (SBO) is not well defined. We sought to analyze the effect of differing therapeutic paradigms in this subpopulation.
Materials and Methods: We retrospectively analyzed NSCLC patients with 1-4 SBO diagnosed between 1/2000 and 1/2011 at our institution. Patients with T0 tumors or documented Karnofsky Performance Status <70 were excluded. Aggressive thoracic therapy (ATT) was defined as resection of the primary disease or chemoradiotherapy whose total radiation dose exceeded 45 Gy. Cox proportional hazards and competing risks models were used to analyze factors affecting survival and first recurrence in the brain.
Results: Sixty-six patients were included. Median follow-up was 31.9 months. Intrathoracic disease extent included 9 stage I, 10 stage II and 47 stage III patients. Thirty-eight patients received ATT, 28 did not. Patients receiving ATT were younger (median age 55 vs. 60.5 years, p=0.027) but were otherwise similar to those who did not. Receipt of ATT was associated with prolonged median overall survival (OS) (26.4 vs. 10.5 months; p<0.001) with actuarial 2-year rates of 54% vs. 26%. ATT remained associated with OS after controlling for age, thoracic stage, performance status and initial brain therapy (HR 0.40, p=0.009). On multivariate analysis, the risk of first failure in the brain was associated with receipt of ATT (HR 3.62, p=0.032) and initial combined modality brain therapy (HR 0.34, p=0.046).
Conclusion: Aggressive management of thoracic disease in NSCLC patients with SBO is associated with improved survival. Careful management of brain disease remains important, especially for those treated aggressively.
Publication Quantitative Clinical Staging for Patients With Malignant Pleural Mesothelioma
(Oxford University Press, 2017) Gill, Ritu; Yeap, Beow; Bueno, Raphael; Richards, WilliamAbstract Background: Analysis of the International Association for the Study of Lung Cancer (IASLC) Malignant Pleural Mesothelioma (MPM) database revealed that clinical (cTNM) staging minimally stratified survival and was discrepant with pathological (pTNM) staging. To improve prognostic classification of MPM, alternative staging models based on quantitative parameters were explored. Methods: An institutional review board–approved MPM registry was queried to identify patients with available pathological and preoperative imaging data. Qualifying patients were randomly assigned to training and test sets in a 1:2 ratio. Computed cTNM and pTNM staging (AJCC Cancer Staging Manual, 7th ed.) were compared. Quantitative image analysis included tumor volume assessed from three-dimensional reconstruction of computed tomography scans (VolCT) and maximal fissural thickness (Fmax). Survival was estimated using the Kaplan-Meier method, and the relationship with VolCT was examined by Cox regression analysis to identify optimized cut-points. Performance of cTNM and quantitative models derived was compared in the test set using Harrell’s C index. Results: A total of 472 patients met inclusion criteria. TNM staging was concordant with pathological TNM staging in 171 of 472 (36.2%), understaged in 209 (44.2%), and overstaged in 92 (19.4%) patients. The most concordant feature was involvement of interlobar fissures. A quantitative clinical staging model comprising VolCT and Fmax (c-index = 0.638, 95% confidence interval [CI] = 0.603 to 0.673) performed statistically significantly better as a prognostic classifier when compared in the test set with cTNM (c-index = 0.562, 95% CI = 0.525 to 0.599, P = .001). Conclusions: Improved prognostic performance may be achievable by quantitative clinical staging combining VolCT and Fmax, providing a cost-effective and clinically relevant surrogate for clinical TNM stage.
Publication The Prognostic Significance of Grading in Lung Adenocarcinoma
(2010-02-01) Barletta, Justine; Yeap, Beow; Chirieac, LucianBackground Although grading has prognostic significance for many tumor types, a prognostically significant grading system for lung adenocarcinoma has not yet been established. The aim of this study was to evaluate histologic characteristics included in tumor grading systems, establish optimal cutoff values that have the strongest association with overall survival, and develop a grading system incorporating the histopathologic characteristics that we found to have prognostic significance in patients with lung adenocarcinoma.
Methods We studied lung adenocarcinomas from 85 consecutive patients, and evaluated the percentage of solid pattern (as a reflection of tumor architecture), the degree of cytologic atypia, and the mitotic count.
Results In univariate analysis, overall survival was associated significantly with sex (P=0.045), age (P=0.0008), tumor status (P<0.0001), node status (P=0.02), solid pattern (P=0.046) and cytologic atypia (P=0.01), but not with mitotic count (P=0.26). Based on optimal cutoff values, we found that a solid pattern ≥ 90% and severe cytologic atypia were the best discriminators of worse outcome. A grading score, computed as the sum of the architecture score and cytologic atypia score (2=well differentiated, 3=moderately differentiated, 4=poorly differentiated), was a significant predictor of overall survival in univariate analysis (median overall survival times 72.4, 39.5, and 8.7 months for well, moderately and poorly differentiated adenocarcinoma, respectively P=0.0001). Moreover, grading was an independent predictor of survival in multivariate analysis (P=0.002).
Conclusions We describe a grading system that incorporates the percentage of solid pattern and degree of the cytologic atypia that is an independent predictor of survival in patients with lung adenocarcinoma.
Publication An Update From the Pediatric Proton Consortium Registry
(Frontiers Media S.A., 2018) Hess, Clayton B.; Indelicato, Daniel J.; Paulino, Arnold C.; Hartsell, William F.; Hill-Kayser, Christine E.; Perkins, Stephanie M.; Mahajan, Anita; Laack, Nadia N.; Ermoian, Ralph P.; Chang, Andrew L.; Wolden, Suzanne L.; Mangona, Victor S.; Kwok, Young; Breneman, John C.; Perentesis, John P.; Gallotto, Sara L.; Weyman, Elizabeth A.; Bajaj, Benjamin V. M.; Lawell, Miranda P.; Yeap, Beow; Yock, TorunnBackground/objectives The Pediatric Proton Consortium Registry (PPCR) was established to expedite proton outcomes research in the pediatric population requiring radiotherapy. Here, we introduce the PPCR as a resource to the oncology community and provide an overview of the data available for further study and collaboration. Design/methods A multi-institutional registry of integrated clinical, dosimetric, radiographic, and patient-reported data for patients undergoing proton radiation therapy was conceived in May 2010. Massachusetts General Hospital began enrollment in July of 2012. Subsequently, 12 other institutions joined the PPCR and activated patient accrual, with the latest joining in 2017. An optional patient-reported quality of life (QoL) survey is currently implemented at six institutions. Baseline health status, symptoms, medications, neurocognitive status, audiogram findings, and neuroendocrine testing are collected. Treatment details of surgery, chemotherapy, and radiation therapy are documented and radiation plans are archived. Follow-up is collected annually. Data were analyzed 25 September, 2017. Results: A total of 1,854 patients have consented and enrolled in the PPCR from October 2012 until September 2017. The cohort is 55% male, 70% Caucasian, and comprised of 79% United States residents. Central nervous system (CNS) tumors comprise 61% of the cohort. The most common CNS histologies are as follows: medulloblastoma (n = 276), ependymoma (n = 214), glioma/astrocytoma (n = 195), craniopharyngioma (n = 153), and germ cell tumors (n = 108). The most common non-CNS tumors diagnoses are as follows: rhabdomyosarcoma (n = 191), Ewing sarcoma (n = 105), Hodgkin lymphoma (n = 66), and neuroblastoma (n = 55). The median follow-up is 1.5 years with a range of 0.14 to 4.6 years. Conclusion: A large prospective population of children irradiated with proton therapy has reached a critical milestone to facilitate long-awaited clinical outcomes research in the modern era. This is an important resource for investigators both in the consortium and for those who wish to access the data for academic research pursuits.