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Featured researches published by K. Amarantidis.


American Journal of Clinical Oncology | 2013

Transtympanic Injections of N-acetylcysteine for the Prevention of Cisplatin-induced Ototoxicity A Feasible Method With Promising Efficacy

Maria Riga; Leonidas Chelis; Stylianos Kakolyris; Stergios Papadopoulos; Sofia Stathakidou; Eleni Chamalidou; Nikolaos Xenidis; K. Amarantidis; Prokopios Dimopoulos; Vasilios Danielides

Objectives:Ototoxicity is a common and irreversible adverse effect of cisplatin treatment with great impact on the patients’ quality of life. N-acetylcysteine is a low-molecular-weight agent which has shown substantial otoprotective activity. The role of transtympanic infusions of N-acetylcysteine was examined in a cohort of patients treated with cisplatin-based regimens. Patients and Methods:Twenty cisplatin-treated patients were subjected, under local anesthesia, to transtympanic N-acetylcysteine (10%) infusions in 1 ear, during the hydration procedure preceding intravenous effusion of cisplatin. The contralateral ear was used as control. The number of transtympanic infusions was respective to the number of administered cycles. Hearing acuity was evaluated before each cycle with pure tone audiometry by an audiologist blinded to the treated ear. Results:A total of 84 transtympanic infusions were performed. In treated ears, no significant changes in auditory thresholds were recorded. In the control ears cisplatin induced a significant decrease of auditory thresholds at the 8000 Hz frequency band (P=0.008). At the same frequency (8000 Hz), the changes in auditory thresholds were significantly larger for the control ears than the treated ones (P=0.005). An acute pain starting shortly after the injection and lasting for a few minutes seemed to be the only significant adverse effect. Conclusions:Transtympanic injections of N-acetylcysteine seem to be a feasible and effective otoprotective strategy for the prevention of cisplatin-induced ototoxicity. Additional studies are required to further clarify the efficiency of this treatment and determine the optimal dosage and protocol.


European Radiology | 2009

Treatment response classification of liver metastatic disease evaluated on imaging. Are RECIST unidimensional measurements accurate

Michael Mantatzis; Stylianos Kakolyris; K. Amarantidis; Anastasios J. Karayiannakis; Panos Prassopoulos

The purpose of this study was to evaluate the accuracy of unidimensional measurements (response evaluation criteria in solid tumors, RECIST) compared with volumetric measurements in patients with liver metastases undergoing chemotherapy. Forty-four patients with newly diagnosed liver lesions underwent three MRI examinations at treatment initiation, during chemotherapy, and immediately post-treatment. Measurements based on RECIST guidelines and volume calculations were performed on the “target” lesions (TLs). The two methods were in agreement in 64/77 of patients and 253/301 of individual lesions classification in response categories (“good” agreement, Cohen kappa = 0.735 and 0.741, respectively). In 16.88% of the comparisons the two methods stratified patients to a different response category; 27.6% of TLs did not follow the response category of the patient in whom lesions were located. The actual volume of TLs differs from the calculated volume of a sphere with the same diameter. Our study supports the use of volumetric techniques that may overcome certain disadvantages of unidimensional measurements.


Mutation Research | 2015

Prognostic role of APC and RASSF1A promoter methylation status in cell free circulating DNA of operable gastric cancer patients

Ioanna Balgkouranidou; Dimitrios Matthaios; Anastasios J. Karayiannakis; Helen Bolanaki; P. Michailidis; Nikos Xenidis; K. Amarantidis; Leonidas Chelis; Grigorios Trypsianis; Ekaterini Chatzaki; Evi S. Lianidou; Stylianos Kakolyris

Gastric carcinogenesis is a multistep process including not only genetic mutations but also epigenetic alterations. The best known and more frequent epigenetic alteration is DNA methylation affecting tumor suppressor genes that may be involved in various carcinogenetic pathways. The aim of the present study was to investigate the methylation status of APC promoter 1A and RASSF1A promoter in cell free DNA of operable gastric cancer patients. Using methylation specific PCR, we examined the methylation status of APC promoter 1A and RASSF1A promoter in 73 blood samples obtained from patients with gastric cancer. APC and RASSF1A promoters were found to be methylated in 61 (83.6%) and 50 (68.5%) of the 73 gastric cancer samples examined, but in none of the healthy control samples (p < 0.001). A significant association between methylated RASSF1A promoter status and lymph node positivity was observed (p = 0.005). Additionally, a significant correlation between a methylated APC promoter and elevated CEA (p = 0.033) as well as CA-19.9 (p = 0.032) levels, was noticed. The Kaplan-Meier estimates of survival, significantly favored patients with a non-methylated APC promoter status (p = 0.008). No other significant correlations between APC and RASSF1A methylation status and different tumor variables examined was observed. Serum RASSF1A and APC promoter hypermethylation is a frequent epigenetic event in patients with early operable gastric cancer. The observed correlations between APC promoter methylation status and survival as well as between a hypermethylated RASSF1A promoter and nodal positivity may be indicative of a prognostic role for those genes in early operable gastric cancer. Additional studies, in a larger cohort of patients are required to further explore whether these findings could serve as potential molecular biomarkers of survival and/or response to specific treatments.


Oncology | 2011

Docetaxel plus Oxaliplatin in Combination with Capecitabine as First-Line Treatment for Advanced Gastric Cancer

K. Amarantidis; N. Xenidis; L. Chelis; E. Chamalidou; P. Dimopoulos; P. Michailidis; A. Tentes; S. Deftereos; M. Karanikas; Anastasios J. Karayiannakis; Stylianos Kakolyris

Objective: In the present phase II study, we evaluated the efficacy and safety of a docetaxel-oxaliplatin-capecitabine combination as a first-line treatment in patients with advanced gastric cancer. Patients and Methods: A total of 27 patients (18 males) with histologically confirmed inoperable gastric adenocarcinoma were recruited. Docetaxel was given (50 mg/m2 i.v.) on day 1 followed by oxaliplatin (75 mg/m2 i.v.) also on day 1. Capecitabine (2,750 mg/m2) was given orally as two daily divided doses from days 1 to 7. Cycles were repeated every 2 weeks. All patients had measurable disease and 18 of them had a performance status (WHO) of 0. Results: A total of 240 treatment cycles were administered. All patients were evaluable for toxicity. Four patients who discontinued treatment early (having received only 3 chemotherapy cycles) were included as non-responders in an intention-to-treat response analysis. Complete response, partial response, stable disease and progressive disease were observed in 4 (15%), 12 (44%), 3 (11%) and 8 (30%) patients, respectively. The observed response rate was 59%, and the disease control rate (complete response + partial response + stable disease) was 70%. At the time of analysis, 6 patients were still alive and the median survival was 18.0 months. The most common grade III/IV toxicities observed were neutropenia (5%), diarrhea (2%), palmar-plantar erythrodysesthesia (2%) and neurotoxicity (1%). All other toxicities were mostly of grade I/II and easily manageable. Conclusion: The combination of docetaxel, oxaliplatin and capecitabine in the described mode of administration represents a relatively active and well-tolerated regimen in patients with advanced gastric cancer and warrants further evaluation.


Chemotherapy | 2010

Biweekly Vinorelbine and Gemcitabine as Second-Line Treatment and Beyond in Non-Small Cell Lung Cancer

Leonidas Chelis; Nikolaos Xenidis; K. Amarantidis; P. Prassopoulos; E. Chamalidou; K. Neanidis; D. Mikroulis; Ekaterini Chatzaki; Petros Karakitsos; Stylianos Kakolyris

Background: To evaluate the activity and tolerance of gemcitabine (GEM) in combination with vinorelbine (VRL) in pretreated patients with advanced non-small cell lung cancer (NSCLC). Patients and Methods: Fifteen patients with advanced NSCLC who had disease progression after a cisplatin- or taxane-based front-line regimen were enrolled into a 2-stage design trial and were treated with VRL 30 mg/m2 i.v. for 10 min followed by GEM 1,200 mg/m2 i.v. for 30 min on days 1 and 15 of each 28-day cycle. Chemotherapy was given for 6 cycles unless disease progression or unacceptable toxicity was seen. The patients’ median age was 64 years and the performance status (WHO) was 0 (n = 7), 1 (n = 5), and 2 (n = 3). The treatment was second line for 10 (67%) and third line or more for 5 (33%) patients. Results: No complete or partial responses were observed. Stable disease was seen in 4 (27%) patients and progressive disease in 11 (73%). The median time to tumor progression was 3 months (range 1–12) and the median survival was 4 months (range 2–31). Severe myelotoxicity was infrequent. Grade 2 neutropenia was observed in 2 (13%) patients, grade 2 thrombocytopenia in 1 (7%), and grade 2 anemia in 3 (20%). Nonhematologic toxicities were very mild and easily manageable. Conclusion: The GEM plus VRL combination at the present doses and schedule is a safe but ineffective regimen; therefore, it is not recommended as second-line treatment in patients with advanced NSCLC.


Oncology Research | 2005

VEGF expression in the colorectal adenoma-carcinoma sequence.

Loukas Kaklamanis; Miltiades Trichas; K. Amarantidis; Nikol Spathari; Anastasia Micheli; Anastasios J. Karayiannakis; Ekaterini Chatzaki; Vasilis Georgoulias; Stelios Kakolyris

Angiogenesis is essential for tumor growth and metastasis. It is controlled by multiple factors, one of the most important being vascular endothelial growth factor (VEGF). VEGF and p53 expression were evaluated in 16 hyperplastic polyps, 35 solitary tubular and tubulovillous adenomas, and 47 cases of sporadic colorectal carcinomas arising on the basis of preexisting adenomas, using immunohistochemistry. In parallel, angiogenesis was assessed by the Chalkley score (CS) method. VEGF positivity was detected in 19/47 carcinoma cases (40%). In the respective adenomatous part of the tumor, VEGF positivity was detected in 11/47 cases (23%). Carcinomas arising from VEGF-positive adenomas were mostly VEGF positive (10/11, 91%), whereas in 28/36 (78%) carcinomas arising from VEGF-negative adenomas VEGF expression was not detected. CS was higher in VEGF-positive compared with VEGF-negative carcinomas (9.1 +/- 1.8 and 7.8 +/- 2.3, respectively, p < 0.05), whereas there was no statistically significant difference between the CS in the VEGF-negative and VEGF-positive adenomatous part of the tumor (3.3 +/- 1.8 and 4.3 +/- 2.3, respectively). Nuclear p53 positivity was detected in 26/47 (55%) cases in the cancerous part and in 14/47 (29%) cases in the adenomatous part of the tissue, and no significant correlation with VEGF expression was observed. We conclude that VEGF associates with angiogenesis in colorectal cancer, and its pattern of expression in adenomas is maintained in the arising carcinomas. Further investigation is warranted to clarify whether these findings could be used as indicators of prognosis in screening programs or in patients with limited stage disease where the usefulness of adjuvant therapies with either cytotoxic drugs or inhibitors of angiogenesis is still unclear.


Oncology | 2005

A Dose Escalation Study of Pegylated Liposomal Doxorubicin (Caelyx) in Combination with Capecitabine (Xeloda) in Patients with Refractory Solid Tumors

E. Maltezos; K. Amarantidis; M. Trichas; M. Vasiliadis; M. Toromanidou; Ekaterini Chatzaki; Anastasios J. Karayiannakis; Alexandra K. Tsaroucha; K. Romanidis; Stylianos Kakolyris

Objective: Pegylated liposomal doxorubicin (PLD) and capecitabine (CAP) have separately shown significant antitumor activity in a wide range of solid tumors. A phase I study was conducted in order to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of their combination in patients with refractory solid tumors. Patients and Methods: Fifteen patients with histologically confirmed inoperable solid neoplasms were enrolled. The patients’ median age was 65 years, 10 were male, and 12 had a performance status score (WHO) of 0–1. PLD was administered on day 1 as a 1-hour intravenous infusion at escalated doses ranging from 35 to 40 mg/m2. CAP was administered on days 1–14 per os, at escalated doses ranging from 1,600 to 1,800 mg/m2, given as two daily divided doses. Treatment was repeated every 3 weeks. Results: At the dose of PLD 40 mg/m2 and CAP 1,800 mg/m2, all 3 enrolled patients presented DLTs [2 patients grade 3 palmar-plantar erythrodysesthesia (PPE) and 1 patient grade 3 asthenia] and thus, the recommended MTD for future phase II studies is PLD 40 mg/m2 and CAP 1,700 mg/m2. A total of 57 treatment cycles were administered. Grade 2/3 neutropenia complicated 9 (17%) cycles and 1 patient was hospitalized for febrile neutropenia. There was no septic death. The main nonhematologic toxicity was PPE grade 2 in 3 (19%) patients and grade 3 in 4 (27%). PPE was the reason of treatment interruption for 3 patients. Other toxicities were mild and easily manageable. Two patients (16%) with partial response suffering from gastric cancer and 5 patients with (42%) stable disease were observed among 12 evaluable patients. Conclusions: The results of this phase I study demonstrate that PLD and CAP can be combined at clinically effective and relevant doses. However, PPE is a common side effect and further investigation is warranted to define its precise role in the treatment of solid malignancies.


Acta Oncologica | 2010

A dose escalation study of docetaxel plus capecitabine in combination with oxaliplatin in patients with advanced solid tumors.

K. Amarantidis; Nikolaos Xenidis; Leonidas Chelis; Anestis Chiotis; Apostolos Tentes; Ekaterini Chatzaki; Alexandros Kortsaris; Alexandros Polychronidis; Petros Karakitsos; Stylianos Kakolyris

Abstract Objectives. Capecitabine (CAP), Oxaliplatin (OX) and Docetaxel (DOC) have shown considerable activity in a wide range of solid tumors. A phase I study was conducted in order to determine the maximum-tolerated dose (MTD) and dose-limiting toxicities (DLTs) of their combination in patients with advanced solid tumors. Patients and methods. Twenty-one patients were enrolled. The patients median age was 68 years, 15 were male, and 12 were chemo-naïve. DOC was administered on day 1 as an 1-hour (iv) infusion at a standard dose of 50 mg/m2. OX was administered on day 1 as a 2-hour (iv) infusion at escalating doses ranging from 70–80 mg/m2. CAP was administered orally on days 1 to 7 at escalating doses ranging from 2 000–2 750 mg/m2 given as two daily divided doses. Treatment was repeated every two weeks. Results. Six different dose-levels were examined. At dose-level VI, two of three enrolled patients presented DLTs (one patient diarrhea and asthenia grade 3 and another grade 3 diarrhea), and thus, the recommended MTD for future phase II studies is CAP 2 750 mg/m2 , DOC 50 mg/m2 and OX 75 mg/m2. A total of 121 treatment cycles were administered. Grade 3 neutropenia was observed in six (5%) treatment cycles and grade 3 thrombocytopenia in one (1%). There was no febrile episode. Grade 3 asthenia was observed in three (14%) patients, grade 3 diarrhea in four (19%), grade 3 neuropathy in one (5%), and grade 1/2 hand-foot syndrome in three (14%). Other toxicities were uncommon. There was no treatment related death. Four (29%) PRs and seven (50%) SD were observed among 14 evaluable patients. Responses were seen in patients with renal (n = 1), gastric (n = 2) and pancreatic (n = 1) cancer. Conclusions. These results demonstrate that CAP, DOC and OX can be safely combined at clinically relevant doses and this regimen merits further evaluation.


Oncology Letters | 2016

Methylation status of the APC and RASSF1A promoter in cell‑free circulating DNA and its prognostic role in patients with colorectal cancer

Dimitrios Matthaios; Ioanna Balgkouranidou; Anastasios J. Karayiannakis; Helen Bolanaki; Nikolaos Xenidis; K. Amarantidis; Leonidas Chelis; Konstantinos Romanidis; Aikaterini Chatzaki; Evi S. Lianidou; Grigorios Trypsianis; Stylianos Kakolyris


Cancer Chemotherapy and Pharmacology | 2012

Docetaxel plus gemcitabine in combination with capecitabine as treatment for inoperable pancreatic cancer: a phase II study

Nikolaos Xenidis; L. Chelis; K. Amarantidis; E. Chamalidou; P. Dimopoulos; N. Courcoutsakis; Antonios-Apostolos K. Tentes; A. Chiotis; P. Prassopoulos; Stylianos Kakolyris

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Stylianos Kakolyris

Democritus University of Thrace

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Ekaterini Chatzaki

Democritus University of Thrace

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Leonidas Chelis

Democritus University of Thrace

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Dimitrios Matthaios

Democritus University of Thrace

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Petros Karakitsos

National and Kapodistrian University of Athens

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Alexandra K. Tsaroucha

Democritus University of Thrace

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Evi S. Lianidou

National and Kapodistrian University of Athens

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