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Featured researches published by Kostas Kalbakis.


Journal of Clinical Oncology | 2009

Cytokeratin-19 mRNA-Positive Circulating Tumor Cells After Adjuvant Chemotherapy in Patients With Early Breast Cancer

Nikolaos Xenidis; Michail Ignatiadis; Stella Apostolaki; Maria Perraki; Kostas Kalbakis; S. Agelaki; Efstathios N. Stathopoulos; Grigorios Chlouverakis; Evi S. Lianidou; S. Kakolyris; Vassilis Georgoulias; Dimitris Mavroudis

PURPOSE To evaluate the prognostic significance of cytokeratin-19 (CK-19) mRNA-positive circulating tumor cells (CTCs) in peripheral blood of women with early-stage breast cancer after the completion of adjuvant chemotherapy. PATIENTS AND METHODS Blood was obtained from 437 patients with early breast cancer before the start and after the completion of adjuvant chemotherapy, and the presence of CK-19 mRNA-positive CTCs was assessed by real-time reverse transcriptase polymerase chain reaction. Interaction with known prognostic factors and association of CTCs with clinical outcome were investigated. RESULTS CK-19 mRNA-positive CTCs were detected before chemotherapy in 179 patients (41.0%). After adjuvant chemotherapy, a significant change in CK-19 status was observed, as status for 51% of patients with initially CK-19 mRNA-positive disease turned negative, and status for 22% of patients with initially CK-19 mRNA-negative disease became positive (McNemar test P = .004). The detection of CK-19 mRNA-positive CTCs postchemotherapy was associated with involvement of more than three axillary lymph nodes (P = .026). Clinical relapses and disease-related deaths were significantly increased in patients with detectable postchemotherapy CK-19 mRNA-positive CTCs (both P < .001, respectively). Disease-free and overall survival were significantly reduced in patients with detectable CK-19 mRNA-positive CTCs postchemotherapy (P < .001 and P = .001, respectively). In multivariate analysis, the detection of CK-19 mRNA-positive CTCs before and after adjuvant chemotherapy was an independent factor associated with reduced disease-free survival (P < .001) and overall survival (P = .003). CONCLUSION The detection of CK-19 mRNA-positive CTCs in the blood after adjuvant chemotherapy is an independent risk factor indicating the presence of chemotherapy-resistant residual disease.


BMC Cancer | 2007

Front-line bevacizumab in combination with oxaliplatin, leucovorin and 5-fluorouracil (FOLFOX) in patients with metastatic colorectal cancer: a multicenter phase II study.

Christos Emmanouilides; Georgia Sfakiotaki; Nikolaos Androulakis; Kostas Kalbakis; Charalambos Christophylakis; Antonia Kalykaki; Lambros Vamvakas; Athanasios Kotsakis; Sofia Agelaki; Eleni Diamandidou; Nikolaos Touroutoglou; Adam Chatzidakis; Vassilis Georgoulias; Dimitris Mavroudis; John Souglakos

PurposeTo evaluate the efficacy and the toxicity of front line FOLFOX4 combined with bevacizumab in patients with metastatsic CRC (mCRC).Patients and MethodsChemotherapy-naïve patients with mCRC, received bevacizumab (5 mg/kg every 2 weeks d1), oxaliplatin (85 mg/m2 on d1), leucovorin (200 mg/m2) on days 1 and 2 and 5-Fluorouracil (400 mg/m2 as i.v. bolus and 600 mg/m2 as 22 h i.v. continuous infusion on days 1 and 2) every 2 weeks.ResultsFifty three patients (46 with a PS 0–1) were enrolled. Complete and partial response was achieved in eight (15.1%) and 28 (52.8%) patients, respectively (ORR: 67.9%; 95% C.I.: 53.8%–92%); 11 (20.7%) patients had stable disease and six (11.3%) progressive disease. With a median follow up period of 13.5 months, time to tumor progression was 11 months while the median survival has not yet been reached; the probability of 1-, 2- and 3- year survival was 79.8%, 63.8% and 58.3%, respectively; Two patients relapsed during the follow up period. Eight (15%) patients underwent metastasectomy with R0 resections. Grade 3–4 neutropenia occurred in 15.1% of patients and one (1.9%) of them presented febrile neutropenia. Non-hematologic toxicity included grade 3 diarrhea (7.6%) and grade 2 and 3 neurotoxicity in 16.9 and 15.1% of patients, respectively. One (1.9%) patient presented pulmonary embolism and one (1.9%) cardiac ischaemia. There was one (1.9%) sudden death after the first cycle.ConclusionThe combination of FOLFOX4/bevacizumab appears to be highly effective, well tolerated and merits further evaluation in patients with mCRC.


American Journal of Clinical Oncology | 2000

Frontline treatment of advanced gastric cancer with docetaxel and granulocyte colony-stimulating factor (G-CSF): a phase II trial.

Dimitris Mavroudis; Charalambos Kourousis; Nikos Androulakis; Kostas Kalbakis; S. Agelaki; Stylianos Kakolyris; John Souglakos; Evi Sarra; N. Vardakis; Dora Hatzidaki; G. Sarmonis; V. Georgoulias

We conducted a phase II study to evaluate the efficacy and tolerance of docetaxel monotherapy with granulocyte colony-stimulating factor (G-CSF) support in patients with advanced gastric cancer. Thirty patients with measurable advanced gastric cancer were enrolled. Twenty-four patients were chemotherapy-naive and six patients had previously received adjuvant chemotherapy after complete surgical resection. Docetaxel was administered at 100 mg/m2 IV during 1 hour every 3 weeks. G-CSF 5 microg/kg SC was also given on days 2 through 8 prophylactically to all patients. All patients were evaluable for response and toxicity. We observed one complete and five partial responses for an overall response rate of 20% (95% confidence interval: 6-34%). In addition, seven patients (23%) had stable disease. After a median follow-up time of 7 months, the median duration of response was 4.5 months, the median time of tumor progression was 6 months, and the median survival was 7 months. The estimated probability of 1-year survival was 28%. Toxicity was generally mild. Grade III/IV neutropenia occurred in 11 (36%) patients. Neutropenia with fever developed in three patients (10%). There were no toxic deaths. Docetaxel with G-CSF support is an active drug and well tolerated by patients with advanced gastric cancer. Docetaxel merits further investigation in combination with other active agents as frontline treatment in patients with advanced gastric cancer.


Breast Cancer Research | 2011

Cytokeratin-19 mRNA-positive circulating tumor cells during follow-up of patients with operable breast cancer: prognostic relevance for late relapse

Emmanouil Saloustros; Maria Perraki; Stella Apostolaki; Galatea Kallergi; Alexandros Xyrafas; Kostas Kalbakis; S. Agelaki; Antonia Kalykaki; Vassilis Georgoulias; Dimitris Mavroudis

BackgroundThe detection of cytokeratin-19 (CK-19) mRNA-positive circulating tumor cells (CTC) before and/or after adjuvant chemotherapy in patients with operable breast cancer is associated with poor clinical outcome. Reliable prognostic markers for late disease relapse are not available. In this study we investigated the value of CTC detection during the first five years of follow-up in predicting late disease relapse.MethodsBlood was analyzed from 312 women with operable breast cancer who had not experienced disease relapse during the first two years of follow-up. A real-time reverse transcriptase polymerase chain reaction (RT-PCR) for CK-19 mRNA was used to detect CTC three months after the completion of adjuvant chemotherapy and every six months thereafter for a follow-up period of five years.ResultsEighty patients (25.6% of the study population) remained CTC free throughout the five-year period. A change in CTC status was observed in 133 patients (42.6%); 64 patients (20.5%) with initially CK-19 mRNA-positive CTC during the first 24 months turned CTC-negative afterwards while 69 (22.1%) who were initially CTC-negative became CTC-positive. Ninety-nine patients (31.7%) remained persistently CK-19 mRNA-positive. After a median follow-up period of 107 months (range: 38 to 161 months), the persistently CTC-positive patients with either hormonal receptor positive or negative tumors, had a higher risk of late-disease relapse compared to the persistently CTC-negative patients (36.4% versus 11.2%, P <0.001). Multivariate analysis revealed that persistently CTC-positive patients also had a shorter disease-free (P = 0.001) and overall survival (P = 0.001).ConclusionsPersistent detection of CK-19 mRNA-positive CTC during the first five years of follow-up is associated with an increased risk of late relapse and death in patients with operable breast cancer and indicates the presence of chemo-and hormonotherapy-resistant residual disease. This prognostic evaluation may be useful when deciding on subsequent adjuvant systemic therapy.


American Journal of Clinical Oncology | 2000

Successful conservative treatment of neutropenic enterocolitis complicating taxane-based chemotherapy : a report of five cases

Charalambos Kouroussis; George Samonis; Nikos Androulakis; John Souglakos; Argiro Voloudaki; Meletios-Athanasios Dimopoulos; Thanos Kotsakis; Stelios Kakolyris; Kostas Kalbakis; Vassilis Georgoulias

Five cases of acute neutropenic enterocolitis complicating taxane-based chemotherapy are described. During a 34-month period, our department administered 4,600 courses of taxane-based (paclitaxel and docetaxel) chemotherapy to 800 cancer patients. Seven to 10 days postchemotherapy in five patients (0.1% of the given courses), neutropenic fever, abdominal pain, rebound tenderness, and grade II-IV diarrhea (bloody in two cases) developed. Two patients had oral candidiasis, and in two others septic shock developed. Computed tomography scans of the abdomen revealed in all patients thickening of the colon wall and pericolic edema, and a pericolic abscess was revealed in three of them. Both clinical and radiologic findings supported the diagnosis of acute neutropenic enterocolitis. All patients were successfully treated with broad-spectrum antibiotics and recombinant human granulocyte colony-stimulating factor. In conclusion, acute neutropenic enterocolitis is a severe complication of taxane-based chemotherapy. Early diagnosis and appropriate conservative treatment leads to complete recovery. Although rare, this infection is less often associated with other chemotherapeutic regimens.


Oncology | 2006

A multicenter phase II study of docetaxel in combination with gefitinib in gemcitabine-pretreated patients with advanced/metastatic pancreatic cancer

Michail Ignatiadis; Aris Polyzos; George Gp Stathopoulos; Evangelos Tselepatiotis; Charalambos Christophylakis; Kostas Kalbakis; Lambros Vamvakas; Athanasios Kotsakis; Anna Potamianou; Vassilis Georgoulias

Purpose: To evaluate the efficacy and tolerance of the docetaxel/gefitinib combination as second-line treatment in patients with advanced pancreatic cancer. Patients and Methods: Twenty-six patients pretreated with gemcitabine-based chemotherapy were enrolled in the study. Docetaxel (75 mg/m2, i.v.) was administered every 3 weeks for a maximum of 6 cycles and gefitinib (250 mg/day, p.o.) was given continuously. Results: Five (19.2%) patients achieved stable disease. The median duration of disease control was 4.8 months (range 1–13.2), the median time to disease progression 2.1 months (range 1–7.3) and the median survival time 2.9 months (range 1–13.9). Grade 3/4 neutropenia was recorded in 9 (34.6%) patients, although only 1 (3.8%) developed grade 2 febrile neutropenia. One (3.8%) patient experienced grade 3 fatigue and 2 (7.7%) grade 3 diarrhea. Grade 1/2 rash was observed in 13 (50%) patients. There were no treatment-related deaths. Conclusion: The docetaxel/gefitinib combination, although safe, has no activity as salvage treatment for advanced pancreatic cancer after failure of gemcitabine-based chemotherapy.


Breast Cancer Research | 2006

Central nervous system relapse in patients with breast cancer is associated with advanced stages, with the presence of circulating occult tumor cells and with the HER2/neu status

John Souglakos; Lambros Vamvakas; Stella Apostolaki; Maria Perraki; Zacharenia Saridaki; Irine Kazakou; Athanasios G. Pallis; Charalambos Kouroussis; Nikos Androulakis; Kostas Kalbakis; Georgia Millaki; Dimitris Mavroudis; Vassilis Georgoulias

IntroductionTo evaluate the incidence of central nervous system (CNS) involvement in patients with breast cancer treated with a taxane-based chemotherapy regimen and to determine predictive factors for CNS relapse.MethodsThe medical files of patients with early breast cancer (n = 253) or advanced stage breast cancer (n = 239) as well of those with other solid tumors (n = 336) treated with or without a taxane-based chemotherapy regimen during a 42-month period were reviewed. HER2/neu overexpression was identified by immunohistochemistry, whereas cytokeratin 19 (CK-19) mRNA-positive circulating tumor cells (CTCs) in the peripheral blood were identified by real-time PCR.ResultsThe incidence of CNS relapse was similar in patients suffering from breast cancer or other solid tumors (10.4% and 11.4%, respectively; P = 0.517). The incidence of CNS relapse was significantly higher in breast cancer patients with advanced disease (P = 0.041), visceral disease and bone disease (P = 0.036), in those who were treated with a taxane-containing regimen (P = 0.024), in those with HER2/neu-overexpressing tumors (P = 0.022) and, finally, in those with detectable CK-19 mRNA-positive CTCs (P = 0.008). Multivariate analysis revealed that the stage of disease (odds ratio, 0.23; 95% confidence interval, 0.007–0.23; P = 0.0001), the HER2/neu status (odds ratio, 29.4; 95% confidence interval, 7.51–101.21; P = 0.0001) and the presence of CK-19 mRNA-positive CTCs (odds ratio, 8.31; 95% confidence interval, 3.97–12.84; P = 0.001) were independent predictive factors for CNS relapse.ConclusionCNS relapses are common among breast cancer patients treated with a taxane-based chemotherapy regimen, patients with HER2/neu-positive tumor and patients with CK-19 mRNA-positive CTCs.


PLOS ONE | 2015

Efficacy of Lapatinib in Therapy-Resistant HER2-Positive Circulating Tumor Cells in Metastatic Breast Cancer

Sofia Agelaki; Antonia Kalykaki; Harris Markomanolaki; Maria Papadaki; Galatea Kallergi; Dora Hatzidaki; Kostas Kalbakis; D. Mavroudis; Vassilis Georgoulias

Background To evaluate the efficacy of lapatinib, a dual EGFR and HER2 tyrosine kinase inhibitor, in therapy-resistant HER2-positive CTCs in metastatic breast cancer (MBC). Patients and Methods Patients with MBC and HER2-positive CTCs despite disease stabilization or response to prior therapy, received lapatinib 1500 mg daily in monthly cycles, till disease progression or CTC increase. CTC monitoring was performed by immunofluorescent microscopy using cytospins of peripheral blood mononuclear cells (PBMCs) double stained for HER2 or EGFR and cytokeratin. Results A total of 120 cycles were administered in 22 patients; median age was 62.5 years, 15 (68.2%) patients were post-menopausal and 20 (90.1%) had HER2-negative primary tumors. At the end of the second course, HER2-positive CTC counts decreased in 76.2% of patients; the median number of HER2-positive CTCs/patient also declined significantly (p = 0.013), however the decrease was significant only among patients presenting disease stabilization (p = 0.018) but not among those with disease progression during lapatinib treatment. No objective responses were observed. All CTC-positive patients harbored EGFR-positive CTCs on progression compared to 62.5% at baseline (p = 0.054). The ratio of EGFR-positive CTCs/total CTCs detected in all patients increased from 17.1% at baseline to 37.6% on progression, whereas the mean percentage of HER2-negative CTCs/patient increased from 2.4% to 30.6% (p = 0.03). Conclusions The above results indicate that lapatinib is effective in decreasing HER2-positive CTCs in patients with MBC irrespectively of the HER2 status of the primary tumor and imply the feasibility of monitoring the molecular changes on CTCs during treatment with targeted agents. Trial Registration Clinical trial.gov NCT00694252


Supportive Care in Cancer | 2012

Nutritional status, acute phase response and depression in metastatic lung cancer patients: correlations and association prognosis.

Zoe Giannousi; Ioannis Gioulbasanis; Athanasios G. Pallis; Alexandros Xyrafas; Danai Dalliani; Kostas Kalbakis; Vassilis Papadopoulos; Dimitris Mavroudis; Vassilis Georgoulias; Christos N. Papandreou

Background and aimCancer cachexia is a metabolic syndrome related with poor outcome. Cytokines play a key role in the pathophysiology of that syndrome. The aim of this study was to investigate the potential correlations between nutritional status, systemic inflammation, and psychological distress in cancer patients. The prognostic significance of the recorded parameters was also assessed.Patients and methodsPatients with metastatic lung cancer were eligible. Mini Nutritional Assessment (MNA) was used for the evaluation of nutritional status, Glasgow Prognostic Score (GPS) for the estimation of systemic inflammation, and Hospital Anxiety and Depression Scale (HADS) for psychological assessment.ResultsTotally, 122 patients were enrolled (71.3% with NSCLC and 28.7% with SCLC). The following correlations were observed: MNA and GPS (r = 0.289, p = 0.001), MNA and HADS (depression scale) (r = 0.275, p = 0.002), GPS and HADS (depression scale) (r = 0.256, p = 0.004), and GPS and HADS (anxiety scale) (r = 0.194, p = 0.033). In univariate analysis, GPS (p = 0.002) and MNA (p = 0.010) emerged as significant predictors of survival. In multivariate analysis, both MNA (p = 0.032) and GPS (p = 0.020) retained their importance.ConclusionsThis study highlights the associations between nutritional status, systemic inflammation, and psychological distress, supporting their common underlying pathophysiological mechanisms and further suggesting the necessity of a holistic anti-cachectic approach.


American Journal of Clinical Oncology | 2002

Irinotecan (CPT-11) in combination with infusional 5-fluorouracil and leucovorin (de Gramont regimen) as first-line treatment in patients with advanced colorectal cancer: a multicenter phase II study.

Lambros Vamvakas; Stylianos Kakolyris; Charalambos Kouroussis; K. Kandilis; Dimitris Mavroudis; N. Ziras; Nikos Androulakis; Kostas Kalbakis; Evi Sarra; John Souglakos; V. Georgoulias

The combination of CPT-11 with 5-fluorouracil (5-FU) in advanced colorectal cancer (ACC) represents an attractive approach. A phase II study was conducted to assess the tolerance and efficacy of CPT-11 in combination with leucovorin-modulated bolus plus infusional 5-FU given according to the de Gramont regimen in chemonaive patients with ACC. Fifty-four patients with histologically confirmed ACC were enrolled. The patients’ median age was 65 years; 30 (55.5%) patients were men; performance status (World Health Organization) was 0 in 27 (50%) patients, 1 in 22 (41%), and 2 in 5 (9%). Patients received leucovorin (200 mg/m2/d) as a 2-hour intravenous infusion, followed by 5-FU as an intravenous bolus at 400 mg/m2/d, and then as a 22-hour continuous infusion at 600 mg/m2/d, repeated on 2 consecutive days. CPT-11 (180 mg/m2; 30-minute intravenous infusion) was administered on day 1, simultaneously with leucovorin administration. This cycle was repeated every 2 weeks. Complete response was achieved in 4 patients (8%) and partial response in 19 (37%) (overall response rate: 45%; 95% CI: 24–50.5%). Stable disease was achieved in 16 (31%) patients and progressive disease in 13 (25%). The median duration of response and the median TTP were 5 and 8 months, respectively. After a median follow-up period of 11 months, 33 (61%) patients are still alive; the median overall survival has not yet been reached. Thrombocytopenia and anemia were very rare. Grade III/IV neutropenia developed in 19 patients (36%); febrile neutropenia developed in 4 patients, and 1 of them died of sepsis. Grade IV diarrhea was seen in 7 (13%) patients, and 4 of them required hospitalization. Grade III and IV mucositis was observed in two (4%) and one (2%) patients, respectively. Other toxicities were mild. The combination of CPT-11 and bolus plus infusional 5-FU is a relatively well-tolerated and effective first-line treatment in ACC. Final results from large phase III trials are awaited to clarify whether the CPT-11/5-FU combinations should be considered as “standard” first-line treatment in ACC.

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Vassilis Georgoulias

National and Kapodistrian University of Athens

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Lambros Vamvakas

National and Kapodistrian University of Athens

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Stylianos Kakolyris

Democritus University of Thrace

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