Emmanuel Chrysos

Prof. Emmanuel Chrysos

University of Crete Greece

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

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

Representative Publications

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24 May 2024 in Cancers
Verified
Journal Article
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Taxiarchis Konstantinos NikolouzakisTaxiarchis Konstantinos Nikolouzakis
Taxiarchis Konstantinos Nikolouzakis
ECEmmanuel Chrysos
Emmanuel Chrysos
Anca Oana DoceaAnca Oana Docea
Anca Oana Docea
PFPersefoni Fragkiadaki
Persefoni Fragkiadaki
John SouglakosJohn Souglakos
John Souglakos
Aristidis TsatsakisAristidis Tsatsakis
Aristidis Tsatsakis
Cancer of the colon and rectum (CRC) has been identified among the three most prevalent types of cancer and cancer-related deaths for both sexes. Even though significant progress in surgical and chemotherapeutic techniques has markedly improved disease-free and overall survival rates in contrast to those three decades ago, recent years have seen a stagnation in these improvements. This underscores the need for new therapies aiming to augment patient outcomes. A number of emerging strategies, such as immune checkpoint inhibitors (ICIs) and adoptive cell therapy (ACT), have exhibited promising outcomes not only in preclinical but also in clinical settings. Additionally, a thorough appreciation of the underlying biology has expanded the scope of research into potential therapeutic interventions. For instance, the pivotal role of altered telomere length in early CRC carcinogenesis, leading to chromosomal instability and telomere dysfunction, presents a promising avenue for future treatments. Thus, this review explores the advancements in CRC immunotherapy and telomere-targeted therapies, examining potential synergies and how these novel treatment modalities intersect to potentially enhance each other’s efficacy, paving the way for promising future therapeutic advancements.

Verified
Journal Article
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MVMaria Venianaki
Maria Venianaki
AAAlexandros Andreou
Alexandros Andreou
Taxiarchis Konstantinos NikolouzakisTaxiarchis Konstantinos Nikolouzakis
Taxiarchis Konstantinos Nikolouzakis
ECEmmanuel Chrysos
Emmanuel Chrysos
GCGeorge Chalkiadakis
George Chalkiadakis
Konstantinos LasithiotakisKonstantinos Lasithiotakis
Konstantinos Lasithiotakis
Malnutrition is associated with dismal treatment outcomes in older patients but its impact in geriatric surgery has not been studied extensively. Herein, we report the prevalence of malnutrition risk, its risk factors and its association with postoperative outcomes in older patients undergoing operations of general surgery. This is a retrospective analysis of a prospectively maintained database including patients older than 65 years who were to undergo general surgery operations between 2012 and 2017. The Malnutrition Universal Screening Tool (MUST) was used for nutritional risk. Demographics, socioeconomic data, site and magnitude of the operation, various measures of comorbidity and functional dependence as well as postoperative complications based on Clavien–Dindo classification and length of stay were recorded. There were 501 patients. A total of 28.6% of them were at intermediate malnutrition risk (MUST = 1) and 14.6% were at high malnutrition risk (MUST ≥ 2). Variables independently associated with malnutrition risk (MUST ≥ 1) were smoking (Odds Ratio, OR:1.6, p = 0.041), upper gastrointestinal (GI) tract surgery (OR:20.4, p < 0.001), hepatobiliary-pancreatic surgery (OR:3.7, p = 0.001), lower GI surgery (OR:5.2, p < 0.001) and American Society of Anesthesiologists (ASA) class III/IV (OR:2.8, p = 0.001). In the multiple regression analysis adjusted for several confounding variables, the MUST score was significantly associated with postoperative death (OR:9.1, p = 0.047 for MUST = 1 and OR:11.9, p = 0.035 for MUST score ≥ 2) and postoperative hospital stay (adjusted incidence rate ratio, 1.3, p = 0.041 for MUST = 1 and 1.7, p < 0.001 for MUST ≥ 2). Malnutrition risk was highly prevalent in this sample, particularly in patients with operations of the gastrointestinal tract, in patients with poor physical status and it was associated with postoperative mortality and length of stay.

14 December 2021 in Journal of Clinical Medicine
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Journal Article
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SKStamatios Kokkinakis
Stamatios Kokkinakis
MVMaria Venianaki
Maria Venianaki
GPGeorgia Petra
Georgia Petra
ACAlexandros Chrysos
Alexandros Chrysos
ECEmmanuel Chrysos
Emmanuel Chrysos
Konstantinos LasithiotakisKonstantinos Lasithiotakis
Konstantinos Lasithiotakis
The optimal malnutrition screening tool in geriatric surgery has yet to be determined. Herein, we compare two main tools in older patients undergoing general surgery operations. Older patients (>65 years old) who underwent general surgery operations between 2012 and 2017 in a tertiary centre were included. The Malnutrition Universal Screening Tool (MUST) and the Mini Nutritional Assessment Short Form (MNA-SF) were used for nutritional risk assessment. Preoperative variables as well as postoperative outcomes were recorded prospectively. Agreement between tools was determined with the weighted kappa (κ) statistic. Multiple regression analysis was used to assess the association of the screening tools with postoperative outcomes. A total of 302 patients (median age 74 years, range: 65–92) were included. A similar number of patients were classified as medium/high risk for malnutrition with the MNA-SF and MUST (26% vs. 36%, p = 0.126). Agreement between the two tools was moderate (weighted κ: 0.474; 95%CI: 0.381–0.568). In the multivariate analysis, MNA-SF was associated significantly with postoperative mortality (p = 0.038) and with postoperative length of stay (p = 0.001). MUST was associated with postoperative length of stay (p = 0.048). The MNA-SF seems to be more consistently associated with postoperative outcomes in elderly patients undergoing general surgery compared with the MUST tool.

15 April 2026 in Journal of Clinical Medicine
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Journal Article
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Taxiarchis Konstantinos NikolouzakisTaxiarchis Konstantinos Nikolouzakis
Taxiarchis Konstantinos Nikolouzakis
EKEpameinondas Evangelos Kantidakis
Epameinondas Evangelos Kantidakis
RCRichard Crawford
Richard Crawford
RPRiaan Pretorius
Riaan Pretorius
OZOrfeas Nikolaos Zaimakis
Orfeas Nikolaos Zaimakis
ECEmmanuel Chrysos
Emmanuel Chrysos
Patient Blood Management (PBM) has evolved from a transfusion-centered practice to a structured, patient-focused perioperative strategy aimed at improving surgical outcomes while preserving blood resources. In the operating room, where bleeding risk is anticipated and modifiable, PBM requires proactive intervention rather than reactive transfusion. This review synthesizes current evidence on perioperative blood conservation strategies specifically relevant to surgeons and anesthesiologists. Preoperative optimization begins with systematic identification and correction of anemia, most commonly iron deficiency, using appropriately timed oral or intravenous iron therapy and, in selected cases, erythropoiesis-stimulating agents. Careful management of anticoagulant and antiplatelet therapies, early recognition of acquired or inherited coagulopathies, and protocol-driven reversal strategies further reduce perioperative hemorrhagic risk. Intraoperatively, blood conservation depends on meticulous surgical technique, respect for anatomical planes, minimally invasive approaches, and the judicious use of advanced energy devices and topical hemostatic agents. Pharmacologic interventions—particularly tranexamic acid administered with appropriate timing and dosing—have demonstrated consistent reductions in blood loss and transfusion requirements across multiple surgical disciplines. Goal-directed coagulation management guided by viscoelastic testing allows targeted correction of specific hemostatic deficits while minimizing unnecessary blood product exposure. Acute normovolemic hemodilution and intraoperative cell salvage provide additional benefit in selected high-blood-loss procedures. Collectively, these multimodal strategies shift perioperative care from product-driven transfusion toward physiology-based blood conservation. When embedded within institutional protocols and supported by multidisciplinary collaboration, perioperative PBM reduces transfusion exposure, decreases morbidity, shortens hospital stay, and promotes sustainable stewardship of blood resources without compromising patient safety.

24 April 2022 in Journal of Clinical Medicine
Verified
Journal Article
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ADAnna Daskalaki
Anna Daskalaki
SXSofia Xenaki
Sofia Xenaki
Konstantinos LasithiotakisKonstantinos Lasithiotakis
Konstantinos Lasithiotakis
ACAlexandros Chrysos
Alexandros Chrysos
Marilena KampaMarilena Kampa
Marilena Kampa
ECEmmanuel Chrysos
Emmanuel Chrysos
Background. Postoperative hypocalcemia is one of the most common complications after total thyroidectomy. Parathormone (PTH) and calcium levels, measured several hours after surgery, have been suggested as valuable markers for detecting patients at risk for post-thyroidectomy hypocalcemia. We aimed to determine if early post-surgery PTH and calcium levels can be used for the early identification of patients at risk for symptomatic hypocalcemia. Methods. PTH and calcium were measured before surgery and at 10 min and 4 h post-thyroidectomy, in 77 patients. Performance characteristics of PTH and calcium levels and their post/pre-surgery ratios were calculated. Results. Four-hour calcium was a sensitive (93.75%) but not specific (67.61%) indicator of patients at risk for symptomatic hypocalcemia. The 4-h/pre-surgery PTH ratio was the most accurate (90.81%) and the most specific (94.37%) test to identify patients at risk. Serum calcium at 4-h, 4-h/pre-surgery PTH ratio, and PTH at 10 min post-surgery had the higher diagnostic odds ratios (50.86, 32.85, and 29.04, respectively). The 4-h/pre-surgery PTH ratio also had the highest (0.694) Youden’s J statistic. Conclusions. Low serum calcium levels 4 h after thyroidectomy and the 4-h/pre-surgery PTH ratio could be valuable additions to everyday clinical practice in post-thyroidectomy patients.

25 March 2026 in Cancers
Verified
Journal Article
Open access
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Taxiarchis Konstantinos NikolouzakisTaxiarchis Konstantinos Nikolouzakis
Taxiarchis Konstantinos Nikolouzakis
John SouglakosJohn Souglakos
John Souglakos
EKEpameinondas Evangelos Kantidakis
Epameinondas Evangelos Kantidakis
KAKaterina Achilleos
Katerina Achilleos
TSTroye van Staden
Troye van Staden
ECEmmanuel Chrysos
Emmanuel Chrysos
Metastatic colorectal cancer (mCRC) accounts for 90% of CRC-related mortality. This review synthesizes insights from comparative genomics tracing evolutionary trajectories from primary tumor to disseminated disease. Multi-region sequencing reveals metastatic seeding often occurs early—before clinical detection—challenging linear progression models. The metastatic bottleneck reduces clonal diversity while enriching for dissemination-competent traits including SMAD4 loss, PTEN inactivation and metabolic reprogramming. Organ-specific adaptation yields distinct molecular signatures: liver metastases exhibit Wnt hyperactivation and TGF-β-driven immune suppression; peritoneal tumors display mucinous features; brain metastases show HER2 enrichment. The immune microenvironment evolves toward immunosuppressive configurations, with Microsatellite instability high (MSI-H) tumors acquiring B2M or JAK1/2 mutations. Circulating tumor DNA (ctDNA) enables real-time tracking of clonal dynamics, detecting molecular residual disease months before radiographic progression. Therapeutic resistance follows predictable evolutionary trajectories—from RAS/BRAF mutations to EGFR ectodomain alterations, HER2/MET amplifications and lineage plasticity—with metastasis-specific mechanisms including microenvironmental protection and cellular dormancy. The clinical future lies in interception: leveraging liquid biopsies for early detection, targeting both tumor-intrinsic vulnerabilities and permissive metastatic niches and adapting therapy dynamically to anticipate resistance. Understanding this genomic odyssey is essential for transforming mCRC into a controllable chronic condition.