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Dive into the research topics where H. Demetriades is active.

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Featured researches published by H. Demetriades.


Diseases of The Colon & Rectum | 2003

Incidence and prognostic value of positive peritoneal cytology in colorectal cancer.

I. Kanellos; H. Demetriades; Elias Zintzaras; A. Mandrali; I. Mantzoros; D. Betsis

AbstractPURPOSE: This study was conducted to investigate the incidence of free cancer cells in the peritoneal washings of patients who had undergone surgery for colorectal cancer and to evaluate its influence as a prognostic factor of the disease. METHODS: From 1990 to 1996, intraoperative washing cytology was performed in 110 patients who underwent surgery for colorectal cancer. All patients had curative resections. Immediately after the abdomen was opened and before exploration and mobilization of the tumor, 100 ml of saline was injected over the tumor site. Washings were then aspirated and taken for cytologic examination. RESULTS: Twenty-two (20 percent) of 110 patients examined were found to have positive cytology for intraperitoneal free malignant cells. The site of tumor in the colon or rectum, tumor size, nodal status, degree of differentiation, mucinous characteristics, and vascular or neural invasion were found not to affect the incidence of free cancer cells. Conversely, tumor penetration was found to affect the incidence of positive cytology. The degree of association among the stages of tumor penetration was indicated by the contingency coefficient, which was 0.42. Patients with positive cytology had a significantly higher rate of local recurrence and peritoneal carcinomatosis (22.8 vs. 8 percent, P = 0.05) than patients with negative cytology. Mortality rate was not found to be related to the presence of free cancer cells. CONCLUSION: Cytologic examination of peritoneal lavage at the time of surgery could be a useful prognostic indicator for local and peritoneal recurrence rate. However, it was not found to be a predictor of survival.


Diseases of The Colon & Rectum | 2004

Healing of colon anastomoses covered with fibrin glue after immediate postoperative intraperitoneal administration of 5-fluorouracil

I. Kanellos; I. Mantzoros; H. Demetriades; S. Kalfadis; T. Kelpis; L. Sakkas; D. Betsis

Purpose: The aim of this experimental study was to investigate whether covering the colonic anastomoses with fibrin glue can protect the colonic healing from the adverse effects of 5-fluorouracil (5-FU), when it is injected intraperitoneally immediately after colon resection. Methods: Sixty-four rats were randomized to one of four groups. After resection of a 1-cm segment of the transverse colon, an end-to-end sutured anastomosis was performed. Rats of the control group and the fibrin glue group were injected with 6 ml of solution 0.9 percent NaCl intraperitoneally. Rats in the 5-FU and the 5-FU + fibrin glue groups received 5-FU intraperitoneally. The colonic anastomoses of the rats in the fibrin glue group and in the 5-FU + fibrin glue group were covered with fibrin glue. All rats were killed on the 8th postoperative day and the anastomoses were examined macroscopically. The bursting pressure measurements were recorded and the anastomoses were graded histologically. Results: The leakage rate of the anastomoses was significantly higher in the rats of the 5-FU group than in those of the fibrin glue group and those of the 5-FU + fibrin glue group (37.5 percent vs. 0 percent, P = 0.020). The adhesion formation score was significantly higher in rats of the 5-FU group than in the other groups. Bursting pressures were also significantly lower in the 5-FUgroup than in the other groups (P < 0.001). Rats in the 5-FU + fibrin glue group developed significantly more marked neoagiogenesis than rats in the other groups. Rats in the 5-FU + fibrin glue group also presented significantly more fibroblast activity than those in the 5-FU group. (P = 0.004) Conclusions: The immediate postoperative, intraperitoneal administration of 5-FU inhibited wound healing. However, when the colonic anastomoses were covered with fibrin glue, the injection of 5-FU had no adverse effects on the healing of the anastomoses


Techniques in Coloproctology | 2004

The failed intraperitoneal colon anastomosis after colon resection

I. Kanellos; Konstantinos Blouhos; H. Demetriades; M. G. Pramateftakis; I. Mantzoros; E. Zacharakis; D. Betsis

BackgroundThe purpose of this study is to present the incidence of anastomotic leakage after colon resection and intraperitoneal anastomosis for colorectal cancer.Patients and methodsIn the last ten years, 205 patients underwent colonic resection with intraperitoneal anastomosis for colon cancer. The surgical management of colorectal cancer consisted of 66 right hemicolectomies, 3 transverse colectomies, 17 left hemicolectomies, 98 sigmoid colectomies and 21 high anterior resections of the rectum. Diagnosis of leakage was made by clinical features, blood vessel examinations and abdominal CT-scans.ResultsAnastomotic leakage occurred in 5 out of 205 patients (2.4%). One of these patients underwent emergency surgery and the other 4 elective surgery; 3 by manual, 2 by mechanical suture. Three patients with anastomotic leakage were reoperated on days 4, 5 and 7, and 2 patients were treated conservatively. Two of the patients (20%) with anastomotic leakage died due to sepsis.ConclusionsEven though the rate of anastomotic leakage in patients with intraperitoneal anastomosis after colon resection for colorectal cancer is low, it remains a significant complication and a major cause of postoperative morbidity and mortality.


Techniques in Coloproctology | 2002

Sutureless colonic anastomosis in the rat: a randomized controlled study

I. Kanellos; I. Mantzoros; H. Demetriades; S. Kalfadis; L. Sakkas; T. Kelpis; D. Betsis

Abstract. The aim of the present study was to evaluate the effect of glue tissue on the healing of colonic anastomosis in rats. Two groups of 20 Wistar rats each were used. Following laparotomy, a segment of 1 cm of the colon was resected, 10 cm from the ileocecal valve. In the control group, the anastomosis was sutured in a single layer with 6-0 polypropylene interrupted extramucosal sutures. In the glue group, the anastomosis was performed by using 2-octyl cyanoacrylate (Dermabond, Ethicon). Rats were sacrificed on day 7 following operation. Integrity of the anastomoses, existence of perianastomotic abscess or peritonitis, and adhesion formation were recorded. Anastomoses were resected including a 2.5-cm of bowel on either side. Bursting pressures were measured and the specimens were sent for histological examination. Anastomotic dehiscence occured in 20% of the animals in each group. Adhesion formation was more extensive in the glue group compared to the control group, but this difference was not statistically significant (p=0.074). Bursting pressures of the anastomoses between the two groups were not statistically significant (p=0.897). The wound healing process, as assessed by inflammatory cell infiltration, blood vessel neodevelopment, collagen deposition and fibroblast activity, did not differ statistically between the two groups (p>0.05). In conclusion, 2-octyl cyanoacrylate provides, under experimental conditions, a sutureless anastomosis equal in healing to the conventionally sutured one. The outcome may differ under demanding clinical situations.


World Journal of Surgical Oncology | 2006

Local excision as a treatment for tumors of ampulla of Vater

H. Demetriades; Emmanouil Zacharakis; Ioanna Kirou; Manousos-Georgios Pramateftakis; Nikolaos Sapidis; I. Kanellos; D. Betsis

BackgroundAlthough local excision (ampullectomy) was first described by Halsted in 1899, its adequacy as an alternative surgical treatment for the ampullary tumors is still a matter of debate. The aim of this study was to evaluate the results of ampullectomy as a curative treatment for benign and malignant tumors arising from the ampulla, in a 14-year single-institution experience.MethodsFrom 1990 to 2004, a total of 20 patients of adenocarcinoma (12) or adenoma (8) of the ampulla of Vater underwent local excision. Clinical data were collected and morbidity, mortality, as well as long-term survival were evaluated. The usefulness of several pre or intraoperative diagnostic methods was also recorded. Median follow-up was 85 (range 6–180) months.ResultsThe combination of endoscopic preoperative biopsies and intraoperative frozen section examination adequately diagnosed ampullary tumors in all cases. The postoperative morbidity and mortality were 0%, whereas the 3 and 5-year survival rates for the patients with adenocarcinoma was 75 % and 33.3 % respectively. All the patients with adenoma are still alive without any sign of recurrence.ConclusionIn our series, local excision was a safe option, associated with satisfactory long-term survival rates in patients with benign lesions and in those with small(<2 cm), pT1, well differentiated ampullary tumours without nodal involvement.


Techniques in Coloproctology | 2004

Effects of steroid on the healing of colonic anastomoses in the rat

I. Mantzoros; I. Kanellos; H. Demetriades; E. Christoforidis; D. Kanellos; M. G. Pramateftakis; T. Zaraboukas; D. Betsis

BackgroundThe aim of this experimental study was to evaluate the effects of steroid on colonic anastomosis in a rat model.MethodsForty female Wistar rats were randomised into two groups. After resection of a 1-cm segment of the transverse colon, an end-to-end sutured anastomosis was performed. In the rats of the control group 2 ml of solution 0.9% NaCl was injected once daily intraperitoneally perioperatively. Rats of the steroid group received intraperitoneally once daily, and on the same perioperative days, hydrocortisone (5 mg/kg body weight in 2 ml solution NaCl). All the rats were sacrificed on the 8th postoperative day and the anastomoses were examined macroscopically. The bursting pressure measurements were recorded and anastomoses were graded histologically.ResultsDehiscence rate was significantly higher in the steroid group than in the control group (p<0.001). Mean bursting pressure was significantly lower in the steroid group compared to the control group (p<0.001). Colonic healing process assessed as inflammatory cell infiltration and collagen deposition was significantly lower in the steroid group than in the control group (p<0.001, p=0.03 respectively).ConclusionsPerioperative steroid treatment adversely affects healing of colonic anastomoses in the rat.


Techniques in Coloproctology | 2002

Low anterior resection without defunctioning stoma

I. Kanellos; E. Zacharakis; E. Christoforidis; H. Demetriades; D. Betsis

Abstract. The aim of our study was to determine the anastomotic leakage rate after the performance of low anterior resection without protective stoma. During the time period from 1989 to 2001, 82 consecutive patients underwent low anterior resection for rectal carcinoma without protective stoma. Thirteen anastomoses were hand sewn (15.8%) and the remaining 69 (84.2%) were constructed with the use of a circular stapling gun. The mean distance of the anastomoses from the anal margin was 6.2 cm (range, 3–9 cm). None of the 82 low anterior resections was covered by a defunctioning stoma. Clinical anastomotic leakage occurred in 4 patients (4.9%) and 4 other patients presented radiologically detected leakage (4.9%). No death occurred in the 8 patients that presented anastomotic dehiscence. Non-specific complications were detected in 11 (13.4%) of 82 patients. In conclusion, the low leakage rate of the anastomoses in our patients allows us to recommend low anterior resection without defunctioning stoma.


Journal of Investigative Surgery | 2007

Contribution of insulin-like growth factor I to the healing of colonic anastomoses in rats.

Emmanouil Zacharakis; H. Demetriades; D. Kanellos; Nikolaos Sapidis; E. Zacharakis; I. Mantzoros; I. Kanellos; Georgios Koliakos; Thomas Zaraboukas; Konstantina Topouridou; D. Betsis

The aim of this experimental study was to investigate the contribution of insulin-like growth factor I (IGF)-I in the colonic healing process when injected intraperitoneally after colon resection. Forty male Wistar rats were used. Rats in the control group were injected with 3 mL of a solution of 0.9% NaCl intraperitoneally after the operation and on postoperative day 2, 4, and 6. Rats in the IGF-I group received recombinant human IGF-I in a dose of 2 mg/kg body weight intraperitoneally, immediately after the colonic anastomosis was performed and on postoperative day 2, 4, and 6. All rats were killed on postoperative day 7. The hydroxyproline tissue content was significantly higher in the IGF-1 group than in the control group. The bursting pressures were also significantly higher in IGF-1 group than in the control group. The weight change between the groups differed significantly; in the control group the average weight decreased about 5% postoperatively, while in the IGF-1 group the average weight increased about 6%. The average inflammatory cell infiltration score was significantly higher in the control group. Neoagiogenesis did not differ significantly between the two groups. The fibroblast activity differed significantly between the two groups, as the control group had significantly less fibroblasts compared to the IGF-1 group. In conclusion, IGF-I when given intraperitoneally stimulates the healing of colonic anastomoses in the rats. Further studies are required in order to determine whether this effect is dose related.


Techniques in Coloproctology | 2004

Pneumomediastinum after dilatation of anal stricture following stapled hemorrhoidopexy

I. Kanellos; Konstantinos Blouhos; H. Demetriades; M. G. Pramateftakis; D. Betsis

Stapling procedure is a new technique for the surgical management of prolapsing haemorrhoids. Some articles have reported severe adverse effects of this operation. We describe a case of an excessive staple-line stenosis followed stapled haemorrhoidopexy. Proctoscopic dilatation resulted in complications of retropneumoperitoneum, pneumomediastinum, subcutaneous emphysema and perianal abscess. Drainage of the abscess was performed, allowing quick recovery. After discharge from the hospital, the patient continued to perform periodic dilatation. Simple proctoscopic dilatation was conducted in an outpatient setting.


Diseases of The Colon & Rectum | 2007

Effect of Iloprost on Impaired Anastomotic Healing Caused by 5-Fluorouracil plus Leucovorin

K. Vasiliadis; M. G. Pramateftakis; Konstantinos Blouhos; I. Mantzoros; George Koliakos; Thomas Zaraboukas; I. Kanellos; H. Demetriades; Daryoush Hamidi Alamdari; D. Betsis

PurposeThis experimental study was designed to investigate whether iloprost can reverse impaired colonic healing caused by immediate postoperative intraperitoneal administration of 5-fluorouracil plus leucovorin.MethodsEighty Wistar rats were randomized into four groups. After resection of a 1-cm segment of transverse colon, an end-to-end sutured anastomosis was generated. Rats received saline solution (Group 1), 5-fluorouracil plus leucovorin (Group 2), iloprost (Group 3), and 5-fluorouracil plus leucovorin plus iloprost (Group 4) intraperitoneally from the day of operation and once daily until killing. Each group was further randomized into two subgroups. Subjects were killed on the fifth (Subgroup a) and eighth (Subgroup b) postoperative days. After killing, anastomoses were examined macroscopically and graded histologically. Rats were measured for anastomotic bursting pressures and tissue hydroxyproline levels.ResultsThe leakage rate of the anastomoses was significantly higher in the 5-fluorouracil plus leucovorin group compared with the other groups (P = 0.049). Bursting pressure was significantly lower in 2a subgroup (5-fluorouracil plus leucovorin, postoperative Day 5) than in 4a (5-fluorouracil plus leucovorin plus iloprost, postoperative Day 5; P < 0.001). Adhesion formation was significantly higher in all b subgroups compared with the Control b subgroup. Neoangiogenesis was significantly higher in iloprost and iloprost plus 5-fluorouracil plus leucovorin subgroups compared with the 5-fluorouracil plus leucovorin subgroups. Hydroxyproline levels, collagen deposition, fibroblasts, and white cell count were significantly higher in the iloprost plus 5-fluorouracil plus leucovorin b subgroup (postoperative Day 8) compared with the 5-fluorouracil plus leucovorin b subgroup (postoperative Day 8).ConclusionsThe immediate postoperative, intraperitoneal administration of iloprost counteracts and reverses the negative effects of 5-fluorouracil plus leucovorin chemotherapy and protects colonic healing in rats.

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I. Kanellos

Aristotle University of Thessaloniki

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D. Betsis

Aristotle University of Thessaloniki

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I. Mantzoros

Aristotle University of Thessaloniki

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D. Kanellos

Aristotle University of Thessaloniki

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Manousos-Georgios Pramateftakis

Aristotle University of Thessaloniki

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Emmanouil Zacharakis

Aristotle University of Thessaloniki

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Konstantinos Blouhos

Aristotle University of Thessaloniki

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M. G. Pramateftakis

Aristotle University of Thessaloniki

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Thomas Zaraboukas

Aristotle University of Thessaloniki

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E. Zacharakis

Aristotle University of Thessaloniki

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