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Dive into the research topics where Nikolaos Charalampakis is active.

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Featured researches published by Nikolaos Charalampakis.


European Journal of Cancer | 2015

18-fluorodeoxy-glucose positron emission computed tomography as predictive of response after chemoradiation in oesophageal cancer patients.

Elena Elimova; Xuemei Wang; Elba C. Etchebehere; Hironori Shiozaki; Yusuke Shimodaira; Roopma Wadhwa; Venkatram Planjery; Nikolaos Charalampakis; Mariela A. Blum; Wayne L. Hofstetter; Jeffrey H. Lee; Brian Weston; Manoop S. Bhutani; Jane E. Rogers; Dipen M. Maru; Heath D. Skinner; Homer A. Macapinlac; Jaffer A. Ajani

INTRODUCTION The purpose of this study was to evaluate if a baseline, an interim or a post-chemoradiation (CTRT) 18-fluorodeoxy-glucose positron emission computed tomography (18F-FDG PET/CT) studies could provide information on pathologic response to CTRT and overall survival (OS). MATERIALS AND METHODS Thirty-one patients with histologically proven adenocarcinoma or squamous cell carcinoma of the oesophagus, fit for trimodality therapy were prospectively enrolled. Most were men (93.5%), and had a stage III cancer (74.2%). Chemotherapy consisted of oxaliplatin/5-fluorouracil (45.2%) and taxane/5-fluorouracil (54.8%). All patients underwent a baseline, an interim (performed 12 ± 2 days after the onset of CTRT) and a post-CTRT 18F-FDG PET/CT study. The 18F-FDG PET/CT variables evaluated were at baseline, interim and post-CTRT studies maximum standardised uptake value (SUV max) and total lesion glycolysis (TLG). Clinical and 18F-FDG PET/CT parameters were correlated with pathologic complete response (pathCR) and OS. RESULTS Among the 31 patients studied, 61.3% achieved a clinical complete response (cCR) and 87.1% had surgery. The median OS was 35.1 months (95% confidence interval (CI): 19.9-NA). PathCR rate was 22.2%. There was only a marginal association between cCR and pathCR (p = 0.06). None of the other variables was predictive of pathCR. There was association between OS and baseline TLG (p = 0.03) at the optimal cutoff TLG value of 75.15. Additionally, TLG and ΔTLG post-CTRT were also associated with OS (p = 0.01 and 0.03, respectively). CONCLUSION None of the PET parameters is predictive of pathCR but TLG at baseline and post-CTRT are prognostic of OS.


Oncology | 2016

The Proportion of Signet Ring Cell Component in Patients with Localized Gastric Adenocarcinoma Correlates with the Degree of Response to Pre-Operative Chemoradiation

Nikolaos Charalampakis; Graciela Nogueras Gonzalez; Elena Elimova; Roopma Wadhwa; Hironori Shiozaki; Yusuke Shimodaira; Mariela A. Blum; Jane E. Rogers; Kazuto Harada; Aurelio Matamoros; Tara Sagebiel; Prajnan Das; Bruce D. Minsky; Jeffrey H. Lee; Brian Weston; Manoop S. Bhutani; Jeannelyn S. Estrella; Brian D. Badgwell; Jaffer A. Ajani

Background: Patients with localized gastric adenocarcinoma (LGAC), who get pre-operative therapy, have heterogeneous/unpredictable outcomes. Predictive clinical variables/biomarkers are not established. Methods: We analyzed 107 LGAC patients who had chemoradiation and surgery. LGACs were grouped for (1) presence/absence of signet ring cell histology (SRC) and (2) histologic grade: G2 or G3. %SRC was assessed (0, 1-10, 11-49, and 50-100%) and correlated with pathologic complete response (pathCR) or <pathCR in the resected specimens. Results: Most patients were men (60%), had stage cIII LGAC (50%), and received chemotherapy before chemoradiation (93%). Most had G3 tumors (78%) and SRC (58%). Presence of SRC was associated with a lower rate of pathCR (11 vs. 36%, p = 0.004), and the association remained significant even with a low percentage of SRC (1-10%; p = 0.014). The higher the fraction of SRC, the lower was the probability of pathCR (p = 0.03). G3 and SRC led to a shorter overall survival (OS) (p = 0.046 and p = 0.038, respectively). yp stage independently prognosticated OS and recurrence-free survival (p < 0.001). Conclusion: Our novel findings suggest that LGACs with SRC are relatively chemoradiation resistant compared to LGACs without SRC. A higher fraction of SRC is associated with higher resistance. Upon validation/biomarker(s) evaluation, reporting of the fraction of SRC may be warranted.


Oncology | 2015

Distribution of Resistant Esophageal Adenocarcinoma in the Resected Specimens of Clinical Stage III Patients after Chemoradiation: Its Clinical Implications

Nastaran Neishaboori; Roopma Wadhwa; Graciela M. Nogueras-Gonzalez; Elena Elimova; Hironori Shiozaki; Kazuki Sudo; Nikolaos Charalampakis; Adarsh Hiremath; Jeffrey H. Lee; Manoop S. Bhutani; Brian Weston; Mariela A. Blum; Jane E. Rogers; Jeana L. Garris; David C. Rice; Ritsuko Komaki; Stephen G. Swisher; Heath D. Skinner; Wayne L. Hofstetter; Jaffer A. Ajani

Background: We have limited knowledge of the geographic distribution of resistant esophageal adenocarcinoma (EAC) in resected specimens, but its clinical importance can be enormous. Method: We selected patients with baseline stage III EAC who had had chemoradiation followed by surgery and had residual EAC (resistant cases only). Outcomes were correlated with various endpoints (percentage of resistant EAC and anatomic distribution). Results: A total of 100 clinical stage III patients were studied; 90% had an R0 resection, and 99% had either moderate or poorly differentiated EAC. Twelve percent had >50% residual cancer, 31% had 11-50% residual cancer, 53% had 1-10% residual cancer, and 3% had positive nodes only. Each compartment was frequently involved: mucosa/submucosa (66%), muscularis propria (76%), and serosa (62%); all compartments were involved in 35% of the cases. Lack of EAC (meaning response) was observed in the mucosa/submucosa (34%), muscularis propria (24%), serosa (38%), and nodes (42%). Although the endoscopic biopsies prior to surgery showed no EAC in 79% of the patients, in the surgical specimens, resistant EAC was frequently occurring in the mucosa/submucosa (66%). Conclusion: Contrary to our hypothesis that resistant EAC would be frequent in the nodes, our data show that its distribution is heterogeneous and unpredictable. Most importantly, the postchemoradiation biopsies are misleading, and a decision to delay/avoid surgery based on negative biopsies can be detrimental for the patients.


Oncology | 2015

Early versus Delayed Therapy of Advanced Gastric Cancer Patients - Does It Make a Difference?

Elena Elimova; Hironori Shiozaki; Rebecca S. Slack; Hsiang Chun Chen; Roopma Wadhwa; Kazuki Sudo; Nikolaos Charalampakis; Adarsh Hiremath; Jeannelyn S. Estrella; Aurelio Matamoros; Tara Sagebiel; Prajnan Das; Jane E. Rogers; Jeana L. Garris; Mariela A. Blum; Brian D. Badgwell; Jaffer A. Ajani

Background: Nearly 50% of gastric cancer patients are diagnosed with advanced gastric cancer (AGC). Therapy is palliative but results in ill effects. The median overall survival (OS) of AGC patients is often <12 months. It is unclear if the early initiation of therapy in all AGC patients is beneficial. Methods: A retrospective analysis of AGC patients in our database was carried out. The patients were divided into two groups: asymptomatic or symptomatic. We sought to assess whether the delay of systemic therapy was harmful in asymptomatic patients. Results: A total of 135 patients were analyzed. Most patients were symptomatic (68%), males (67%), and had low ECOG scores (0-1; 85%). In univariate analyses, ECOG performance status 0 (p = 0.005), delayed initiation of therapy (p = 0.03), and lack of symptoms (p = 0.03) were associated with a longer OS. The multivariate model for OS identified only ECOG performance status as an independent prognosticator of longer OS (p = 0.02). Asymptomatic patients who had delayed (≥4 weeks) systemic therapy had an OS rate of 77% at 1 year compared to 58% for patients treated within 4 weeks (p = 0.47). Conclusion: Symptomatic AGC patients had a poor outcome compared to asymptomatic AGC patients. Treatment delay in asymptomatic patients had no detrimental effect on OS, suggesting that the timing of therapy can be based on patient selection.


Expert Opinion on Pharmacotherapy | 2015

Biologics in Combination with Chemotherapy for Gastric Cancer: Is This the Answer?

Nikolaos Charalampakis; Elena Elimova; Yusuke Shimodaira; Hironori Shiozaki; Roopma Wadhwa; Jaffer A. Ajani

Gastric cancer (GC) continues to be a significant problem worldwide and is the third leading cause of cancer death. Armamentarium to treat GC whether it is potentially curable or metastatic (incurable) has changed little over the last decades with only two new agents being approved (trastuzumab and ramucirumab). Many relatively healthy patients after second-line therapy have limited and generally ineffective options. The recent The Cancer Genome Atlas analysis has uncovered four genotypes of GC; however, it is not sufficient to change our treatment strategies and more work needs to be done. The popular front-line regimen containing a platinum compound and a fluoropyrimidine is widely used for drug development and has worked well globally. Thus, this combination appears suitable for adding a biologic agent. The search for new classes of cytotoxics has almost stopped, but it is clear that cytotoxic therapy continues to contribute and it is here to stay. Biologic agents that modulate the immune system of the host appear promising along with many other biologics that can potentially inhibit signaling pathways that are often employed by GC cells. We will briefly describe the efforts that have targeted EGFR, mTOR, angiogenesis and MET pathways.


Oncology | 2018

Actionable Locoregional Relapses after Therapy of Localized Esophageal Cancer: Insights from a Large Cohort

Elena Elimova; Xuemei Wang; Wei Qiao; Kazuki Sudo; Roopma Wadhwa; Hironori Shiozaki; Yusuke Shimodaira; Venkatram Planjery; Nikolaos Charalampakis; Jeffrey H. Lee; Brian Weston; Manoop S. Bhutani; Ritsuko Komaki; David C. Rice; Stephen G. Swisher; Mariela A. Blum; Jane E. Rogers; Heath D. Skinner; Dipen M. Maru; Wayne L. Hofstetter; Jaffer A. Ajani

Objective: The goal of surveillance after therapy of localized esophageal cancer (LEC) is to identify actionable relapses amenable to salvage; however, the current surveillance algorithms are not optimized. We report on a large cohort of LEC patients with actionable locoregional relapses (LRRs). Methods: Between 2000 and 2013, 127 (denominator = 752) patients with actionable LRR were identified. Histologic/cytologic confirmation was the gold standard. All surveillance tools (imaging, endoscopy, fine needle aspiration) were assessed. Results: Most patients were men (89%), had adenocarcinoma (79%), and had no new symptoms (72%) when diagnosed with LRR. In trimodality patients, endoscopic confirmation of positron emission tomography-computed tomography-suspected LRR occurred in only 44%, and 56% required additional tools (e.g., fine needle aspiration). Alternatively, in bimodality patients, endoscopy confirmed LRRs in 81%. Trimodality patients had a higher risk of subsequent LRR/distant metastases after the first LRR than the bimodality patients (p = 0.03). In all patients, 78% of the subsequent relapses were distant. For patients who were salvaged, survival was significantly prolonged (50.6 vs. 25.1 months, p < 0.01). Conclusions: Patients live longer after successful salvage of the LRR than if salvage is not possible. After LRR, patients have a high risk of subsequent distant metastasis and whether the second relapse is local or distant, survival is uniformly poor.


Oncotarget | 2017

Utility of endoscopic ultrasound-guided fine-needle aspiration of regional lymph nodes that are proximal to and far from the primary distal esophageal carcinoma

Yusuke Shimodaira; Rebecca Slack; Kazuto Harada; Manoop S. Bhutani; Elena Elimova; Gregg Staerkel; Nour Sneige; Jeremy J. Erasmus; Hironori Shiozaki; Nikolaos Charalampakis; Venkatram Planjery; Dilsa Mizrak Kaya; Fatemeh G. Amlashi; Mariela A. Blum; Heath D. Skinner; Bruce D. Minsky; Dipen M. Maru; Wayne L. Hofstetter; Stephen G. Swisher; Jeannette E. Mares; Jane E. Rogers; Quan D. Lin; William A. Ross; Brian Weston; Jeffrey H. Lee; Jaffer A. Ajani

Implications of assessing the proximal and far para-tracheal or sub-carinal nodes (para-tracheal [PTN] or sub-carinal [SCN]) associated with lower primary esophageal carcinomas (ECs) are unclear. To evaluate the value of endoscopic ultrasound guided fine-needle aspiration (EUS-FNA) for PTN and SCN, we analyzed results by positron emission tomography (PET) avidity, 4 EUS node malignancy features, and EUS-FNA results in all patients with Siewerts I or II EC. Of 133 patients (PTN, n=102; SCN, n=31) with EUS-FNA, 47 (35%) patients had malignant node, leading to treatment modifications. EUS-FNA diagnosed significantly more patients with malignant nodes (p=0.02) even when PET and EUS features were combined. Among 94 PET-negative and EUS-negative patients, 9 (10%) had malignant EUS-FNA. At a minimum follow-up of 1 year, only 3 (5%) of 62 patients with benign EUS-FNA had evidence of malignancy in the nodal area of prior EUS-FNA. Patients with malignant EUS-FNA independently had a much shorter overall survival (OS) than those with benign EUS-FNA (p<0.001). Our data suggest that a benign EUS-FNA is highly accurate and need not be pursued further. However, malignant EUS-FNA of PTN/SCN was independently prognostic, conferred a shorter OS, and altered the management of 35% of patients.Implications of assessing the proximal and far para-tracheal or sub-carinal nodes (para-tracheal [PTN] or sub-carinal [SCN]) associated with lower primary esophageal carcinomas (ECs) are unclear. To evaluate the value of endoscopic ultrasound guided fine-needle aspiration (EUS-FNA) for PTN and SCN, we analyzed results by positron emission tomography (PET) avidity, 4 EUS node malignancy features, and EUS-FNA results in all patients with Siewert’s I or II EC. Of 133 patients (PTN, n=102; SCN, n=31) with EUS-FNA, 47 (35%) patients had malignant node, leading to treatment modifications. EUS-FNA diagnosed significantly more patients with malignant nodes (p=0.02) even when PET and EUS features were combined. Among 94 PET-negative and EUS-negative patients, 9 (10%) had malignant EUS-FNA. At a minimum follow-up of 1 year, only 3 (5%) of 62 patients with benign EUS-FNA had evidence of malignancy in the nodal area of prior EUS-FNA. Patients with malignant EUS-FNA independently had a much shorter overall survival (OS) than those with benign EUS-FNA (p<0.001). Our data suggest that a benign EUS-FNA is highly accurate and need not be pursued further. However, malignant EUS-FNA of PTN/SCN was independently prognostic, conferred a shorter OS, and altered the management of 35% of patients.


Journal of Clinical Oncology | 2016

Course and predictors of postoperative outcomes in older patients with localized gastric adenocarcinoma treated preoperatively.

Nikolaos Charalampakis; Lianchun Xiao; Elena Elimova; Yusuke Shimodaira; Hironori Shiozaki; Prajnan Das; Aurelio Matamoros; Tara Sagebiel; Mariela A. Blum; Jeffrey H. Lee; Manoop S. Bhutani; Brian Weston; Paul F. Mansfield; Bruce D. Minsky; Brian D. Badgwell; Jaffer A. Ajani

132 Background: Older patients with localized gastric adenocarcinoma (LGAC) suffer from substantial postoperative morbidity and mortality; however, postoperative outcomes in older patients who have received preoperative chemotherapy and/or chemoradiation have not been reported. Our study examined the impact of age and other covariates on baseline, surgical and postoperative characteristics and explored potential predictors of postoperative outcomes. Methods: Patients with LGAC who were treated with chemotherapy (n = 36; 18%) and/or chemoradiation (n = 167; 82%) followed by surgery (n = 203) were grouped in 2 categories by age: 1) ≥ 65 years old (n = 70) and 2) < 65 years old (n = 133). The short-term outcomes included postoperative morbidity and mortality, and the long-term outcomes overall survival (OS) and progression-free survival (PFS). Potential predictors of 90-day postoperative outcomes were identified i) by age group and ii) by a number of other covariates. Descriptive statistics and survival anal...


Oncology | 2015

Initial Standardized Uptake Value of Positron Emission Tomography Influences the Prognosis of Patients with Localized Gastric Adenocarcinoma Treated Preoperatively.

Nikolaos Charalampakis; Lianchun Xiao; Elena Elimova; Roopma Wadhwa; Hironori Shiozaki; Yusuke Shimodaira; Mariela A. Blum; Venkatram Planjery; Jane E. Rogers; Aurelio Matamoros; Tara Sagebiel; Prajnan Das; Jeffrey H. Lee; Manoop S. Bhutani; Brian Weston; Jeannelyn S. Estrella; Brian D. Badgwell; Jaffer A. Ajani

Background: In patients with localized gastric adenocarcinoma (LGAC) who receive preoperative therapy, tools to predict response or prognosticate outcome before therapy are lacking. We used initial standardized uptake value (iSUV) of positron emission tomography (PET) to evaluate its association with overall survival (OS). Methods: We identified 60 patients with confirmed LGAC who were treated with preoperative chemoradiation and had a baseline PET in addition to other routine staging. Fishers exact test and Wilcoxons rank sum test were used to determine the association between iSUV and other variables, and the log-rank test and Cox proportional hazards model were used for survival analysis. Results: The median iSUV was 6 (range, 0-28). The presence of signet ring cells in pretreatment biopsies correlated highly with low iSUV (≤6; p = 0.0017). Patients with a high iSUV (>6) had a longer OS compared to those with a low iSUV (≤6; p = 0.0344). iSUV was not an independent predictor (p = 0.12); however, the risk of death was reduced for patients with an iSUV >6 (hazard ratio = 0.26). Conclusion: Our novel findings show that among LGAC patients treated with preoperative chemoradiation and surgery, those with a high iSUV have longer OS than patients with a low iSUV. iSUV appears to have a predictive role in patients with LGAC when treated with preoperative chemoradiation.


Oncology | 2015

Contents Vol. 89, 2015

Soo Young Lee; Chang Hyun Kim; Young Jin Kim; Hyeong Rok Kim; Sang-Jae Park; Kyong-Ah Yoon; Sang Myung Woo; Eun Kyung Hong; Mee Kyung Jung; Weon Seo Park; Kieun Bae; Sung-Sik Han; Tae Hyun Kim; Young Hwan Koh; Woo Jin Lee; Joo Young Kim; Hee Jin Lee; In Hye Song; In Ah Park; Jong Han Yu; Gyungyub Gong; Jong Gwang Kim; Soo Yeun Park; Hye Jin Kim; Gyu Seog Choi; Ji Yun Jeong; Ghil Suk Yoon; Shinkyo Yoon; An Na Seo; Jun Seok Park

A.B. Benson, Chicago, Ill. A. Chang, Singapore A.L. Cheng, Taipei J.F. Cleary, Madison, Wis. M. Dietel, Berlin M.S. Ernstoff, Cleveland, Ohio M.G. Fakih, Duarte, Calif. J.J. Grau, Barcelona H. Gronemeyer, Illkirch D.F. Hayes, Ann Arbor, Mich. C.S. Johnson, Buffalo, N.Y. M.J. Kelley, Durham, N.C. L. Kumar, New Delhi P.J. Loehrer, Indianapolis, Ind. J.R. Marshall, Buffalo, N.Y. S. Monfardini, Milan R. Nagler, Haifa R. Ohno, Nagoya B. Pestalozzi, Zurich H.M. Pinedo, Amsterdam E.A. Repasky, Buffalo, N.Y. A. Semczuk, Lublin E.F. Smit, Amsterdam C.N. Sternberg, Rome R. Stupp, Zurich M.S. Tallman, New York, N.Y. S. Tanaka, Hiroshima M. Tian, Houston, Tex. D.L. Trump, Buffalo, N.Y. T. Wiegel, Ulm W. Yasui, Hiroshima H. Zhang, Hangzhou City Editor-in-Chief

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Elena Elimova

University of Texas MD Anderson Cancer Center

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Jaffer A. Ajani

University of Texas MD Anderson Cancer Center

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Hironori Shiozaki

University of Texas MD Anderson Cancer Center

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Mariela A. Blum

University of Texas MD Anderson Cancer Center

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Manoop S. Bhutani

University of Texas MD Anderson Cancer Center

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Brian Weston

University of Texas MD Anderson Cancer Center

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Roopma Wadhwa

University of Texas MD Anderson Cancer Center

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Jane E. Rogers

University of Texas MD Anderson Cancer Center

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Jeffrey H. Lee

University of Texas MD Anderson Cancer Center

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Yusuke Shimodaira

University of Texas MD Anderson Cancer Center

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