Georgios Polychronidis

Dr. Georgios Polychronidis

orcid

Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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24 October 2019 in Cancer Communications
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Journal Article
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JFJincheng Feng
Jincheng Feng
GPGeorgios Polychronidis
Georgios Polychronidis
UHUlrike Heger
Ulrike Heger
GFGiovanni Frongia
Giovanni Frongia
AMArianeb Mehrabi
Arianeb Mehrabi
KHKatrin Hoffmann
Katrin Hoffmann
Background: Hepatoblastoma is a rare disease that nevertheless accounts for the majority of liver malignancies in children. Due to limited epidemiological data, therapy for hepatoblastoma tends to be individualized. This study aimed to evaluate incidence trends of hepatoblastoma and to develop a nomogram to predict the survival of children with newly diagnosed hepatoblastoma on a population‐based level. Methods: Individuals up to 18 years of age with hepatoblastoma recorded in 18 registries of the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015 were examined. Joinpoint regression analyses were applied to assess incidence trends in annual percentage change (APC). Multivariable Cox regression was used to identify factors associated with overall survival (OS). A nomogram was constructed to predict OS in individual cases based on independent predictors. Concordance index (C‐index) and calibration curves were used to evaluate predictive performance. Results: Between 2004 and 2015, hepatoblastoma incidence increased significantly (APC, 2.2%; 95% confidence interval [CI] 0.5% to 3.8%, P < 0.05). In particular, this increase was observed among 2‐ to 4‐year‐old patients, males, and African–Americans. The 5‐ and 10‐year OS rates were 81.5% and 81.0%, respectively. Age of 2 to 4 years, African–American ethnicity, and no surgery were independent predictors for short OS. Distant disease at presentation was found not to be an independent factor of survival. The nomogram had a C‐index of 0.79 (95% CI 0.74–0.84) with appropriate calibration curve fitting. Conclusions: We constructed a nomogram that integrates common factors associated with survival for hepatoblastoma patients. It provides accurate prognostic prediction for children with hepatoblastoma.

27 June 2019 in Investigational New Drugs
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Journal Article
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VMVladimir J. Lozanovski, MD
Vladimir J. Lozanovski, MD
GPGeorgios Polychronidis
Georgios Polychronidis
WGWolfgang Gross
Wolfgang Gross
NGNegin Gharabaghi
Negin Gharabaghi
AMArianeb Mehrabi
Arianeb Mehrabi
Ingrid HerrIngrid Herr
Ingrid Herr
Summary: Pancreatic ductal adenocarcinoma is a highly aggressive malignancy with short survival and limited therapeutic options. Broccoli sulforaphane is a promising new treatment due to the results of recent epidemiological, experimental and patient studies. Upon approval from the ethics committee and registration at ClinicalTrials.gov, 40 patients with palliative chemotherapy were placed into a placebo and treatment group in an unblinded fashion. Fifteen capsules with pulverized broccoli sprouts containing 90 mg/508 μmol sulforaphane and 180 mg/411 μmol glucoraphanin or methylcellulose were administered daily for up to 1 year. Twenty-nine patients were included in the treatment group and 11 patients were in the placebo group; these patients were followed for up to 1 year. The patient characteristics, overall survival and feasibility were assessed. Compared to those of the placebo group, the mean death rate was lower in the treatment group during the first 6 months after intake (day 30: 0%/18%, day 90: 0%/25%, and day 180: 25%/43%), and Kaplan-Meier analysis revealed a higher survival rate. There was a high drop-out rate (72% in the treatment group and 55% in the placebo group) after 1 year. We concluded from the Karnofsky index that the broccoli sprouts did not impact patient’s self-care and overall abilities severely. The intake of 15 capsules daily was difficult for some patients, and the broccoli sprouts sometimes increased digestive problems, nausea and emesis. We did not obtain statistically significant results (p = 0.291 for the endpoint at day 180), but the knowledge about the feasibility is the basis for the development of new sulforaphane drugs.

18 April 2023 in International Journal of Epidemiology
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Journal Article
Closed access
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GPGeorgios Polychronidis
Georgios Polychronidis
HSHaziq Siddiqi
Haziq Siddiqi
FAFasih Ali Ahmed
Fasih Ali Ahmed
SPStefania Papatheodorou
Stefania Papatheodorou
EGEdward Giovannucci
Edward Giovannucci
MSMingyang Song
Mingyang Song
Background: Numerous studies have assessed the association of gallstones or cholecystectomy (CE) with risk of colorectal cancer (CRC). However, the findings are mixed. Objective: To systematically review and meta-analyse the association between the presence of gallstone disease (GD), or CE and the incidence of CRC. Secondary endpoints were the risk based on type of exposure, study design, tumour subsites and sex. Methods: PubMed and EMBASE were searched from September 2020 to May 2021. The protocol was registered on the Open Science Foundation Platform. We identified and classified studies according to their design into prospective cohort, population-based case-control, hospital-based case-control and necropsy studies reporting CRC incidence among individuals with diagnosed GD or after CE (or both). Among 2157 retrieved studies, 65 (3%) met the inclusion criteria. We followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Data were extracted by two independent reviewers. We evaluated the quality of the study according to the Newcastle-Ottawa Scale and only studies with a score of 6 and above were included in the final analyses. We pooled log-transformed odds ratios/risk ratios from the available adjusted models to estimate a summary relative risk (RR) and 95% confidence interval (CI) in a random-effects model. The primary outcome was overall CRC incidence. We also conducted secondary analyses according to sex and CRC subsites (proximal colon, distal colon and rectum). The outcome was measured by RRs with 95% CIs. Results: The overall association of GD and/or CE with CRC was RR = 1.15 (1.08; 1.24), primarily driven by hospital-based case-control studies [RR = 1.61 (1.29; 2.01)], whereas a more modest association was found in population-based case-control and cohort studies [RR = 1.10 (1.02; 1.19)]. Most hospital-based case-control and necropsy studies reported estimates that were adjusted for age and sex only, leaving room for residual confounding; therefore we restricted to population-based case-control and cohort studies for our subsequent analyses. Similar associations were found for women [RR = 1.21 (1.05; 1.4) and men (RR = 1.24 (1.06; 1.44)]. When assessed by CRC subsites, GD and CE were primarily associated with higher risk of proximal colon cancer [RR = 1.16 (1.07; 1.26)] but not distal colon cancer [RR = 0.99 (0.96; 1.03)] or rectal cancer [RR = 0.94 (0.89; 1.00)]. Conclusions: Gallstones are associated with a modestly increased risk of colon cancer, primarily in the proximal colon.

31 August 2016 in Anz Journal of Surgery
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EAEfstathios Antoniou
Efstathios Antoniou
GMGeorgios A. Margonis
Georgios A. Margonis
KSKazunari Sasaki
Kazunari Sasaki
NANikolaos Andreatos
Nikolaos Andreatos
GPGeorgios Polychronidis
Georgios Polychronidis
EPEmmanouil Pikoulis
Emmanouil Pikoulis

13 October 2024 in Journal of Gastrointestinal Surgery
Verified
Journal Article
Open access
MHMax Heckler
Max Heckler
GPGeorgios Polychronidis
Georgios Polychronidis
BKBenedict Kinny-Köster
Benedict Kinny-Köster
SRSusanne Roth
Susanne Roth
THThomas Hank
Thomas Hank
MLMartin Loos
Martin Loos

10 September 2018 in British Journal of Surgery
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Journal Article
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GPGeorgios Polychronidis
Georgios Polychronidis
FHFelix J. Hüttner
Felix J. Hüttner
PCP. Contin
P. Contin
KGK. Goossen
K. Goossen
LUL. Uhlmann
L. Uhlmann
PPPascal Probst
Pascal Probst