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Dive into the research topics where Andreas C. Lazaris is active.

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Featured researches published by Andreas C. Lazaris.


Surgery Today | 2006

Comparison of Monopolar Electrocoagulation, Bipolar Electrocoagulation, Ultracision, and Ligasure

Theodore Diamantis; Michael Kontos; Antonios Arvelakis; Spiridon Syroukis; Dimitris Koronarchis; Apostolos Papalois; Emmanuel Agapitos; Elias Bastounis; Andreas C. Lazaris

PurposeHemostasis is a fundamental principle of surgery. We compared the safety and efficacy of monopolar electrocoagulation (ME), bipolar electrocoagulation (BE), Ligasure (LS), a modern bipolar vessel sealing system, and Ultracision (UC), a system of ultrasound energy based shears. We also studied the healing process after their use.MethodsWe used each of the above methods to coagulate and divide the short gastric vessels of 16 white male New Zealand rabbits. The animals were killed after 3, 7, 14, or 21 days, and the coagulation sites and the adjacent gastric wall were examined histologically.ResultsLS and UC achieved complete hemostasis without any complications. Conversely, ME and BE often resulted in failed coagulation and perforation of the neighboring gastric wall from a side thermal injury. Histologically, LS demonstrated the mildest side thermal injury and the fastest healing process. We noted greater thermal injury and inflammatory response after UC than after LS on days 7 and 14; however, ME and BE caused the most severe lesions.ConclusionsLS and UC are clearly the safest and most efficient methods of coagulation, whereas ME and BE could cause serious clinical and histological complications. We found histological evidence that UC causes a slightly greater inflammatory response than LS, and the clinical implications of this warrant further investigation.


Journal of Clinical Pathology | 2004

The favourable prognostic value of oestrogen receptor β immunohistochemical expression in breast cancer

Lydia Nakopoulou; Andreas C. Lazaris; Effie Panayotopoulou; Ioanna Giannopoulou; N Givalos; Sofia Markaki; Antonios Keramopoulos

Aims: Oestrogen receptor β (ERβ) is present in breast tumours, although its prognostic and pathophysiological roles remain to be established. Methods: Standard immunohistochemistry with a specific monoclonal antibody was performed on paraffin wax embedded sections; 10% of strongly immunostained carcinoma cells was used as the cutoff point to classify tumours as ERβ positive. Statistical correlations were sought with clinicopathological variables (including hormone receptor status) and disease free (DFS) and overall survival (OS) in a well documented series of 181 invasive breast carcinomas. Cell proliferation was assessed immunohistochemically by topoisomerase IIa (TopoIIa) index; p53 protein accumulation and c-erbB-2 oncoprotein expression were also taken into account. Results: ERβ immunoreactivity was detected in most specimens (71.2%); it was positively linked to ERα immunoreactivity and increased TopoIIα index, and inversely to c-erbB-2 overexpression. There were no correlations with p53 immunostaining or other clinicopathological parameters. A significant favourable impact of ERβ immunopositivity emerged with regard to DFS and OS in both univariate and multivariate analysis; ERβ immunopositivity retained its favourable significance with regard to DFS in the subgroups of stage I and II patients when they were examined separately. Progesterone receptor expression also had an independent favourable influence on survival, albeit with less significance. In contrast, survival was not significantly influenced by ERα status. Conclusions: Because of the positive association between ERβ immunoreactivity and TopoIIα expression, the presence of ERβ in breast cancer cells could be considered an indication of increased proliferation. Nevertheless, ERβ immunoreactivity emerges as a valuable, independent indicator of favourable prognosis.


BJUI | 2005

Evaluation of hypoxia‐inducible factor 1α overexpression as a predictor of tumour recurrence and progression in superficial urothelial bladder carcinoma

Vasilios. E. Theodoropoulos; Andreas C. Lazaris; Ioannis Kastriotis; Chariclia Spiliadi; George Theodoropoulos; Vasiliki Tsoukala; Efstratios Patsouris; F. Sofras

To investigate the possible role of hypoxia‐inducible factor 1α (HIF‐1α, a transcription factor important in regulating O2 homeostasis and physiological responses to oxygen deprivation) in the recurrence and progression of superficial urothelial bladder cancer, and to examine its expression in relation to proliferation status, apoptotic activity and intratumoral angiogenesis.


The Journal of Pathology | 1996

Prognostic significance of the co-expression of p53 and c-erbB-2 proteins in breast cancer

Lydia Nakopoulou; Anastasia Alexiadou; George Theodoropoulos; Andreas C. Lazaris; Anastasia Tzonou; Andonis Keramopoulos

The immunohistochemical expression of p53 and c‐erbB‐2 gene proteins was examined in a series of 130 breast adenocarcinomas. This study intended to investigate whether the frequency of the altered expression of the tumour suppressor gene p53 and the overexpression of the oncogene c‐erbB‐2 in breast cancer tissue cells correlated with other variables known to affect the biological behaviour of these tumours and the overall survival of the patients (median follow‐up time: 6 years). The expression of p53 protein and c‐erbB‐2 gene product was evaluated immunohistochemically. Expression of p53 protein was detected in 30 (23 per cent) of the neoplasms examined, while 26 (20 per cent) out of the 130 cases demonstrated positive c‐erbB‐2 immunoreactivity. There was a statistically significant association between p53 protein expression and primary tumour size, lymph node involvement, and oestrogen receptor positivity. The incidence of c‐erbB‐2 positivity was significantly correlated with high tumour grade, axillary node invasion, large tumour size, and the absence of steroid receptors. p53 immuno‐expression was clearly associated with c‐erbB‐2 protein overexpression. Concomitant p53 and c‐erbB‐2 positive immunolabelling, which emerged in 14 out of the 130 cases (10·7 per cent), was clearly associated with high grade, large size, positive nodal status, ductal infiltrating (NOS) histological type, and low values of progesterone receptors. Overall survival of patients was not significantly related to the immunoreactivity of either p53 or c‐erbB‐2 considered separately, whereas there was a clearly significant trend to worse overall prognosis in cancers with double p53/c‐erbB‐2 positive phenotype. The simultaneous immunodetection of p53/c‐erbB‐2 appears to have greater negative prognostic relevance than their separate expression.


Diseases of The Colon & Rectum | 1995

Heat shock protein 70 and HLA-DR molecules tissue expression. Prognostic implications in colorectal cancer.

Andreas C. Lazaris; George Theodoropoulos; Davaris P; Dimitris Panoussopoulos; Lydia Nakopoulou; Christos Kittas; Basil Ch. Golematis

PURPOSE: The expression of 70,000-Da heat shock protein (HSP 70) and HLA-DR molecules on cancer cells influences immunologic mechanisms that may be of some prognostic significance. The purpose of this study was to examine the relationship among immunohistochemical HSP 70, HLA-DR expression, and clinicopathologic tumor variables, as well as patient survival in a series of 128 colorectal carcinomas. METHOD: A three-step immunoperoxidase staining technique was undertaken for detection of both markers. RESULTS: Of the examined carcinomas 77.3 percent were HSP 70-positive and 74.2 percent were HLA-DR-positive. Increased HSP 70-positive expression correlated significantly with low differentiation (P<0.05), showed a tendency to characterize advanced stages of disease, and was clearly associated with worse overall survival (P<0.05). The highest rate of HLA-DR positivity was demonstrated in early stages and was significantly associated with more favorable prognosis (P<0.001). HSP 70-positive/HLA-DR-negative patients had worse overall survival compared with the rest (P<0.001). CONCLUSIONS: The resulting opposite effects on prognosis of examined markers seem to be related to different pathophysiologic functional roles on tumor immunology.


European Urology | 2002

Differential Expression of bcl-2 Family Proteins in Bladder Carcinomas: Relationship with Apoptotic Rate and Survival

Penelope Korkolopoulou; Andreas C. Lazaris; A.E. Konstantinidou; Nikolaos Kavantzas; Efstratios Patsouris; Panayota Christodoulou; Euphemia Thomas-Tsagli; Panagiotis Davaris

OBJECTIVE To elucidate the role of various bcl-2 family molecules in the regulation of apoptosis and the progression of urothelial cancer, in relation to standard prognosticators. METHODS Paraffin-embedded archival tissue from 103 N0M0 consecutive patients with invasive bladder cancer (28 T1, 57 T2, 13 T3 and 5 T4) was immunostained for bcl-2, bax, bcl-XL, bcl-Xs, p53, Ki-67 and with an anti-single stranded DNA monoclonal antibody recognizing the apoptotic cells. Survival analysis was restricted to T2-T4 tumours. Patients were followed-up until death (n = 27) or for a mean (+/- S.D.) follow-up of 37.6 (+/- 17.4) months. Within this period, 39 patients relapsed after a mean (+/- S.D.) period of 13.6 (+/- 12.3) months. RESULTS Most tumours were immunoreactive for bax (73.1%) and bcl-XL (80.9%) whereas bcl-2 and bcl-XS expression was comparatively less common (44.4 and 28.9%, respectively). The bcl-XL and bcl-XS positivity was related to high grade (P = 0.007) and advanced stage (P = 0.010), respectively. On the contrary, bax and bcl-2 positivity was unrelated to stage or grade. Apoptotic rate was independently influenced only by p53, bcl-2 and proliferation rate. In multivariate analysis of T2-T4 urothelial carcinomas (UC)s, only bax along with T-category and age were the significant predictors of disease-free survival. Increased apoptosis and T-category were also independently related to the overall survival in T2-T4 UCs. CONCLUSIONS The expression of bcl-2 family members appears to be differentially regulated in association with UC evolution. Most importantly, bax immunostaining offers additional information to that provided by traditional prognosticators, with regard to disease-free survival of T2-T4 UCs.


Pathobiology | 2000

DNA topoisomerase II-alpha immunoreactivity as a marker of tumor aggressiveness in invasive breast cancer.

Lydia Nakopoulou; Andreas C. Lazaris; Nikolaos Kavantzas; Paraskevi Alexandrou; Pauline Athanassiadou; Antonios Keramopoulos; Davaris P

Objective: The nuclear enzyme DNA topoisomerase (topo) II breaks and rejoins DNA strands; its isoform topo IIα is associated with active cell proliferation of mammalian cells. The aim of this study was to examine the relationship between the expression of topo IIα and biological behavior markers in breast cancer. Methods: Formalin-fixed, paraffin-embedded tissue from 88 samples of infiltrating breast cancer was immunohistochemically stained for topo IIα. For each case, a topo IIα index was determined by image analysis. Similar indexes were available for Ki-67 protein, a known cell proliferation marker, and p53, bcl-2 and c-erbB-2 oncoproteins. Each case had been staged and graded and the patients had been followed up for a mean period of 61.62 months. Results: Elevated topo IIα immunopositivity (in >10% of malignant nuclei) was detected in 22 tumors, and this immunostatus was statistically associated with poor nuclear differentiation, absence of steroid hormone receptors, high Ki-67 immunoexpression, p53 protein accumulation and c-erbB-2 protein overexpression. Topo IIα expression was not linked with disease extent (stage or lymph node status). Neither proliferation marker (topo IIα or Ki-67) had any significant influence on the patients’ recurrence-free survival. Conclusion: From the above results, we conclude that topo IIα overexpression appears to be linked with cellular dedifferentiation and potentially aggressive tumor phenotype in invasive breast cancer.


Dermatology | 2004

Rosacea: A Clinicopathological Approach

Kyriaki Aroni; Eugenia Tsagroni; Andreas C. Lazaris; Efstratios Patsouris; Emmanouil Agapitos

Background: There are few reports of the histological changes in rosacea, and little attempt has been made to correlate such changes with clinical findings. In the present study, we describe in detail the histopathological features of rosacea in a large number of patients and simultaneously investigate the aetiopathogenesis of the disease based on the comparative assessment of epidemiological, clinical and histological findings. Methods: The study included 73 patients with rosacea. A skin biopsy with a 4-mm punch was performed in each case. All biopsy specimens included subcutaneous tissue. In 10 randomly selected patients, facial biopsy specimens were obtained from both involved and uninvolved (non-lesional) skin. Demodex mite presence was estimated semi-quantitatively under light microscopy. Patients with self-reported gastro-intestinal symptoms were submitted to upper gastro-intestinal endoscopy, and a rapid urease test was performed. Serological antibodies, IgG and IgA, against Helicobacter pylori were also detected. Results: The patients had a broad clinical spectrum of lesions. No specific histological features associated with either erythematous-telangiectatic or papulopustular clinical forms were noticed. Histological examination showed that there is no histological pattern unique to rosacea. Three different types of granulomas were observed: small palisaded ones around altered collagen and other granulomas of elastolytic and non-specific epithelioid type, all coexisting in 5 cases. The deep dermis and subcutis were frequently involved. Comparative study in 10 rosacea patients between lesional and non-lesional skin biopsies revealed almost the same histological changes to the latter biopsies, to a lesser degree though. Conclusion: Rosacea seems to be a reaction pattern to which a variety of pathogenetic routes may lead.


Virchows Archiv | 1995

Immunohistochemical expression of C-myc oncogene, heat shock protein 70 and HLA-DR molecules in malignant cutaneous melanoma

Andreas C. Lazaris; George Theodoropoulos; Kiriaki Aroni; Angelica A. Saetta; Davaris P

The clinical course of malignant melanomas is frequently unpredictable, although a number of prognostically useful variables can be identified. There is a need for additional markers of prognostic value. In a series of 60 malignant cutaneous melanomas, we analysed the immunohistochemical expression of c-myc proto-oncogene, heat shock protein 70 (HSP70) and HLA-DR molecules in order to investigate their prognostic significance. C-myc, HSP70 and HLA-DR were expressed in 43.3%, 56.6% and 38.3% of all melanoma cases, respectively. Advanced Clark levels (Clark III–V) were significantly associated with c-myc expression rate (P<0.05), HSP70 detection (P<0.01) and HLA-DR positivity (P<0.01). Increased Breslow thickness (>1.5 mm) was related to HLA-DR expression (P<0.05). High mitotic rate was closely associated with c-myc positivity (P<0.05), while HSP70 and HLA-DR expression separately correlated to clinical stage of the disease (P<0.05). The evaluation of these variables may be of immunological and prognostic significance. They were found to be associated with melanocyte subpopulations of the vertical growth phase which are arguably characterized by an increased invasive potential.


Diseases of The Colon & Rectum | 2005

Assessment of JC polyoma virus in colon neoplasms.

George Theodoropoulos; Dimitris Panoussopoulos; Ioannis Papaconstantinou; Maria Gazouli; Marina Perdiki; John Bramis; Andreas C. Lazaris

PURPOSEResearch data have recently emphasized an intriguing association of JC polyoma virus with colon carcinogenesis. Tumorigenicity of JC virus is attributed to the T-antigen of its Mad-1 variant. Controversy arose when another research group did not confirm this association. The purpose of this study was to detect JC virus in a series of colon neoplasms from Greek patients.METHODSA nested polymerase chain reaction assay was used to detect JC virus in 80 cancerous, 25 adenomatous specimens of large bowel, and 20 colonoscopic biopsy samples from normal patients without colorectal neoplasia. Quantitation of JC virus DNA was performed by real-time polymerase chain reaction.RESULTSJC polyoma virus nucleotide sequence was detected in 61 percent of colon adenocarcinomas and in 60 percent of adenomas, at a viral load of 9 × 103 to 20 × 103 copies/µg DNA. Adjacent normal mucosa in 35 positive colon adenocarcinoma specimens, and normal mucosa from six patients of the control group, had low viral loads (50–450 copies/µg DNA).CONCLUSIONSJC polyoma virus genome is present in colon neoplasms. JC virus detection in adenomas at comparable viral loads to malignant tumors suggests its implication at early steps of colonic carcinogenesis. Taking into consideration other published data, infection of colonic epithelium with JC virus might be a prime candidate for a role in chromosomal and genomic instability.

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Efstratios Patsouris

National and Kapodistrian University of Athens

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George Theodoropoulos

National and Kapodistrian University of Athens

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Nikolaos Kavantzas

National and Kapodistrian University of Athens

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E. Patsouris

National and Kapodistrian University of Athens

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Davaris P

Athens State University

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Christos Yapijakis

National and Kapodistrian University of Athens

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Eleftherios Vairaktaris

National and Kapodistrian University of Athens

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Sofia Spyridonidou

National and Kapodistrian University of Athens

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Antonis Vylliotis

National and Kapodistrian University of Athens

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Stavros Vassiliou

National and Kapodistrian University of Athens

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