G. Alivizatos
National and Kapodistrian University of Athens
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Featured researches published by G. Alivizatos.
Urology | 1994
J.J.M.C.H. de la Rosette; M.J.A.M. de Wildt; G. Alivizatos; E.M. Ja Froeling; E.M.J. Debruyne
OBJECTIVES A prospective, randomized placebo-controlled study was designed to exclude a placebo response in transurethral microwave thermotherapy (TUMT). METHODS During a sham procedure, the microwave applicator was installed in the urethra as in the real TUMT treatment and a complete procedure was simulated by the microwave delivery system (Prostatron). Any patient who entered this study had the option to request a second real TUMT treatment if, 3 months after the initial procedure, his condition had not improved. RESULTS A total of 48 patients were available for evaluation at 3 months and 28 at 6 months. The TUMT group had an average decrease of 7.3 points (from 13.2 to 5.9) in the Madsen symptom score, an average increase in flowrate of 3.4 mL/s (9.6 to 13.0), and an increase in voiding percentage of 9.6% (81.7 to 91.3). All improvements were statistically significant. In the sham group, the average Madsen score decreased from 12.1 to 8.2 points, the average flowrate decreased from 9.7 to 9.5 mL/s, and the voiding percentage increased from 80.8% to 84.3%. Only the change in symptom score was significant. In both groups, observations at the 3-month follow-up were similar to those after 6 and 12 months. Patients who had TUMT after sham treatment showed similar significant changes in symptom score and peak flow as observed in the original TUMT group. Patients who did not respond favorably to a first TUMT did not experience improvement after a second TUMT. CONCLUSIONS A placebo effect, although minimal, exists. This placebo response, however, accounts for little of the observed benefit of TUMT.
Oncology | 2007
Aristotle Bamias; George Lainakis; Efstathios Kastritis; Nikos Antoniou; G. Alivizatos; Andreas Koureas; Michael Chrisofos; Andreas Skolarikos; Evangelos Karayiotis; Meletios A. Dimopoulos
Objective: We evaluated safety and efficacy of first-line gemcitabine/carboplatin in unfit-for-cisplatin patients with advanced urothelial carcinoma and the effect on the quality of life and functional status of elderly patients (aged >70). Methods: Unfit patients had ECOG performance status (PS) ≧2, creatinine clearance <50 ml/min or comorbidities precluding cisplatin administration. Carboplatin at area under the curve of 2.5 and gemcitabine 1,250 mg/m2 were administered biweekly. Elderly patients were stratified into group 1 (no activities of daily living (ADL) or instrumental ADL dependency and no comorbidities), group 2 (instrumental ADL dependency or 1–2 comorbidities) and group 3 (ADL dependency or ≧2 comorbidities). Results: Thirty-four patients were enrolled: 68% had PS 2–3, 69% a creatinine clearance <50 ml/min and 65% had 1 or more comorbidities. There were 3 cases of grade 3 toxicity (9%). Response rate was 24% [95% confidence interval (CI) 11–41]. Median follow-up was 8 months, median progression-free survival 4.4 months (95% CI 1.03–7.75) and median overall survival 9.8 months (95% CI 4.7–14.9). Patients in geriatric assessment groups 1 and 2 had a significantly longer median progression-free survival compared to group 3 [6.9 months (95% CI 1.3–12.4) vs. 1.9 months (95% CI 0.5–3.2); p = 0.005]. Conclusion: First-line gemcitabine/carboplatin combination is active in unfit-for-cisplatin patients with advanced urothelial carcinoma. Pretreatment quality of life and geriatric assessment may be useful in selecting patients likely to benefit from this treatment.
Journal of Endourology | 2010
Andreas Skolarikos; M.P. Laguna; G. Alivizatos; Ali Riza Kural; J.J.M.C.H. de la Rosette
BACKGROUND AND PURPOSE All urinary stones may not need prompt active treatment. The aim of our study was to identify urinary stones that can be actively monitored safely. MATERIALS AND METHODS We performed a systematic review of the natural history and the role of active monitoring for urinary stones. RESULTS Thirty-seven studies have selected. Of symptomatic ureteral calculi <4 mm, 38% to 71% will pass spontaneously while only 4.8% of stones <2 mm will need intervention during surveillance. Follow-up with history, physical examination, urinalysis, and plain radiography every 2 weeks for 1 month is necessary. If spontaneous passage does not occur within this period, intervention is recommended. When shockwave lithotripsy for caliceal stones is prospectively compared with observation, there is no difference in stone-free rates (28% vs 17%), need for additional treatment (15% vs 21%), or visits to a general practitioner (18.5% vs 20.8%). Patients under observation may need more invasive procedures and may be more commonly left with residual stone fragments >5 mm (58% vs 30%). Isolated, nonuric acid calculi <4 mm may be most amenable to active monitoring. Physical examination, urinalysis, and CT scan performed on an annual basis up to year 2 or 3, followed by intervention, are recommended. Lower pole stones <10 mm could be actively monitored on an annual basis by alternating ultrasonoraphy with CT scan, provided the patients are adequately informed. Up to 58.6% and 43% of patients with residual fragments after shockwave and percutaneous lithotripsy, respectively, may become symptomatic or require intervention during follow-up. Noninfected, asymptomatic fragments, <4 mm postextracorporeal lithotripsy, and <2 mm postpercutaneous surgery could be followed expectantly on an annual basis, in combination with medical therapy. CONCLUSION Active stone monitoring has a certain role in the treatment of patients with urinary stones. The success is largely dependent on the stone size, location, and composition, as well as the time after the diagnosis. Medical therapy is a useful adjunct to observation.
Urologia Internationalis | 1994
Ch. Deliveliotis; G. Alivizatos; N.J. Stavropoulos; K. Makrychoritis; G. Koutsokalis; Z. Kiriakakis; A. Kostakopoulos; C. Dimopoulos
The influence of various prostatic manipulations, including digital rectal examination, cystoscopy, transrectal ultrasonography and transrectal needle biopsy, on the serum prostatic-specific antigen (PSA) levels in 170 men, were examined. We found that digital rectal examination, cystoscopy and transrectal ultrasonography had no significant effect on PSA levels, except for transrectal needle biopsy, which caused an immediate increase of serum PSA in 96.2% of the patients lasting more than 2 weeks in 42.3% of the cases. In conclusion, serum PSA determination after digital rectal examination, after cystoscopy and after transrectal ultrasonography is accurate and reliable. On the other hand, we must wait about 6 weeks after needle biopsy before measuring PSA in the serum of patients with prostatic diseases.
European Urology | 2001
S. Giannakopoulos; G. Alivizatos; Ch. Deliveliotis; Andreas Skolarikos; J. Kastriotis; F. Sofras
Encrusted cystitis (EC) and encrusted pyelitis (EP) are rare chronic inflammatory diseases of the bladder and renal pelvis, respectively, and are characterized by mucosal inflammation with deposits of ammonium magnesium phosphate on the urothelium. Corynebacterium urealyticum is the pathogen responsible in the vast majority of cases. We report 4 cases of EC and 1 case of EP. In 1 case of EC Ureaplasma urealyticum was isolated as the microorganism responsible. To the best of our knowledge, U. urealyticum–induced EC has never been reported previously.
European Urology | 1994
J.J.M.C.H. de la Rosette; F. M. J. A. Froeling; G. Alivizatos; F.M.J. Debruyne
Twenty-four patients with benign prostatic hyperplasia were treated with the Nd:YAG laser. We review our experience with two different techniques: the ultrasound-guided transurethral laser-induced prostatectomy (TULIP) and the visual laser ablation of the prostate (VLAP). Our experience with these two different laser systems shows that the treatment is relatively simple, speedy and performed with virtually no blood loss. The results, of both the TULIP and VLAP procedures, are excellent. The symptom scores decrease from 43 to 19 (TULIP) and 48 to 9 (VLAP). Furthermore, there is a marked increase in average uroflow from 7.9 to 18.6 ml/s (TULIP) and from 8.1 to 18.0 ml/s (VLAP). The patients with the TULIP procedure, however had more pronounced posttreatment complaints. These patients more often received antibiotics. Laser therapy of the prostate, although still in its infancy, gives excellent results and has substantial advantages over conventional transurethral resection of the prostate (TURP). Laser therapy may replace TURP within several years.
Journal of Endourology | 2004
F. Sofras; K. Livadas; G. Alivizatos; Ch. Deliveliotis; S. Albanis; Michael D. Melekos; K. Christoforidis
PURPOSE To identify patients with ureteropelvic junction (UPJ) obstruction who will benefit from endoscopic Acucise incision of the stenosis and to compare the open Hynes-Anderson pyeloplasty with this minimally invasive technique. PATIENTS AND METHODS In a prospective trial, 22 patients with primary and secondary UPJ obstruction were treated by Acucise endopyelotomy, and 18 patients were treated by Hynes-Anderson pyeloplasty. Preoperative and postoperative renal scans were used to determine the degree of obstruction and intravenous urography, ultrasound scanning, or both to assess the degree of dilation. RESULTS There was a vast difference in the cure rate of the two groups: Hynes-Anderson pyeloplasty cured 94.5% of the patients, while in the Acucise group, the cure rate was only 32%. There was some improvement in another 22% of the patients, but the renal scan curve remained obstructed. The remaining 45% of patients failed to show any improvement. CONCLUSION Acucise endopyelotomy will improve or cure only patients with good renal function and mild dilation of the pelvicaliceal system. Patients with severe dilation should be treated by Hynes-Anderson pyeloplasty.
Urologia Internationalis | 1996
Charalambos Deliveliotis; Giannakopoulos S; Louras G; G. Koutsokalis; G. Alivizatos; A. Kostakopoulos
In this study, we treated patients with a solitary distal ureteral stone of less than 10 mm in maximum diameter by placing a double-pigtail stent and subsequently removing it allowing the calculus to pass spontaneously. A total of 40 patients were enrolled in the study with a mean stone size of 5.1 x 3.5 mm (range 2-8 mm in length and 2-7 mm in width). The indication for intervention was intractable pain in 5 patients, infection due to obstruction in 2, highly obstructed urinary tract in 10, absence of progression for 30 days in 21 and desire of the patient to be free of stone in 2. A double-pigtail stent was inserted in the involved ureter under local anesthesia and left in place for 2 weeks. After stent removal, 34 patients succeeded in passing the stone within an average time of 5.8 days. The overall success rate was 85%. We suggest this method as an alternative form of treatment for distal ureteral calculi to extracorporeal shockwave lithotripsy of ureterolithotripsy under selected clinical circumstances.
Urologic Oncology-seminars and Original Investigations | 2011
Aristotelis Bamias; G. Aravantinos; Ioannis Kastriotis; G. Alivizatos; Ioannis Anastasiou; Christos Christodoulou; Reveka Gyftaki; Haralabos P. Kalofonos; Meletios A. Dimopoulos
OBJECTIVES Stage I testicular nonseminomatous germ-cell tumors (NSGCT) are highly curable. Following orchidectomy surveillance, adjuvant chemotherapy and retroperitoneal lymph node dissection can be applied. Certain factors are used to select patients in high-risk for relapse. We report the outcome and safety of a risk-adapted strategy by the Hellenic Cooperative Oncology Group. METHODS Between 1994 and 2004, 142 patients with stage I NSGCT and 1 of the following risk factors: lymphovascular invasion (LVI), invasion of tunica vaginalis, spermatic cord, rete testis or scrotal wall, embryonal component >50% of the total tumor, were prospectively included in a protocol of adjuvant chemotherapy consisting of two 3-week courses of bleomycin 15 IU, etoposide 120 mg/m(2), and cisplatin 40 mg/m(2) for 3 consecutive days with G-CSF support. RESULTS Median follow-up was 79 months and 138 patients have been followed for at least 2 years. Seventy-seven patients (54%) had LVI and 74 (52%) had >50% embryonal component. There was 1 relapse, which was cured with chemotherapy and surgery. Another patient died due to disease-unrelated causes and 1 patient developed a new primary of the remaining testicle, which was cured with surgery. CONCLUSION Two cycles of bleomycin/etoposide/cisplatin is an effective and safe form of adjuvant therapy in high-risk stage I NSGCT.
European Urology | 1992
G. Alivizatos; K. Pavlaki; A. Giannopoulos; D. Mitropoulos; A. Tsega; Ch. Deliveliotis; C. Dimopoulos
Twenty-eight cases of prostatic adenocarcinomas have been selected and the mean argyrophil nucleolar organizer region (AgNOR) count for each case was evaluated. Nine of these tumors were of high, 13 of median and 6 of low differentiation. It was found that as the tumors became less differentiated, the AgNOR count increased (p less than 0.001). Stage of the disease, serum prostate-specific antigen (PSA) value, and DNA ploidy of all these cases have been examined as well but no statistically significant correlation among these three parameters and the AgNOR count was found.