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Biomedical subjects

C Dimopoulos

Publications and source records attributed to C Dimopoulos.

At least 19 recordsLinked to original sources
PubMed1998

Treatment of patients with metastatic urothelial carcinoma and impaired renal function with single-agent docetaxel.

OBJECTIVES: To evaluate the efficacy and toxicity of single-agent docetaxel in patients with metastatic urothelial carcinoma and impaired renal function. METHODS: Eleven consecutive patients previously untreated for metastatic disease with renal impairment (median serum creatinine level of 2.6 mg/dL) were treated with intravenous docetaxel 100 mg/m2 for 1 hour every 21 days. Granulocyte colony-stimulating factor was administered at a dose of 5 microg/kg/day subcutaneously from days 5 to 14. RESULTS: Five of 11 patients achieved a partial response, with time to progression of responding patients ranging from 5 to 22 months or more. The median overall survival rate was 11 months. Renal function improved in 5 of 8 patients with tumor-related renal impairment. Toxicity was primarily hematologic, with 5 patients developing grade 3 or 4 neutropenia; nonhematologic toxicities were manageable. CONCLUSIONS: Our preliminary data indicate that single-agent docetaxel therapy may represent an effective therapeutic alternative for patients with advanced urothelial carcinoma and renal insufficiency precluding cisplatin-based combination chemotherapy.

Aged↗
PubMed1998

Efficacy of escalating doses of intravesical interferon alpha-2b in reducing recurrence rate and progression in superficial transitional cell carcinoma.

OBJECTIVE: To compare the efficacy of three different doses of intravesical interferon alpha-2b (IFN alpha-2b) in reducing recurrence and progression rates in superficial grade II, transitional cell carcinoma (TCC). PATIENTS AND METHODS: Eighty-nine patients with primary or recurrent TCC stage Ta/T1, grade II, were randomly allocated into four groups after transurethral resection (TUR) of the tumour. Group A (20 patients) received no further treatment, serving as the control group; group B (22 patients) received 40 MU of IFN alpha-2b, group C (24 patients) 60 MU and group D (23 patients) 80 MU. The instillations started within 48-72 h after TUR and were performed weekly for 2 months, bimonthly for the next 4 months and thereafter monthly for 6 months. The patients were followed for 36 months. The four groups were compared for the number of recurrences (simple recurrence rate), progression in stage, disease-free interval and recurrence rate per 100 patient-months. RESULTS: During the follow-up, 33 patients had recurrence (13, eight, seven and five in groups A to D, respectively). The simple recurrence rate was 65% for group A, compared with 36% (P = 0.06), 29% (P < 0.05) and 22% (P < 0.01) for groups B, C and D, respectively. The differences in simple recurrence rates between the groups treated with IFN alpha-2b were not statistically significant. Eleven patients experienced progression in stage, with six, there, one and one in groups A to D, respectively. The differences were statistically significant only between groups A and C (P < 0.05) and groups A and D (P < 0.05). The disease-free interval was 15 months for group A, compared with 21.4 (P < 0.05), 26.1 (P < 0.001) and 30 months (P < 0.001) for groups C to D, respectively. The disease-free intervals of the groups treated with IFN alpha-2b were significantly different between all patients in groups B and D (P < 0.01) and only for those with stage T1 between groups C and D (P < 0.01). Finally the recurrence rate per 100 patient-months was 2.91, 1.19, 0.88 and 0.63 for groups A to D, respectively (all P < 0.001). The results were always in favour of the patients treated with the high dose, the only exception being the difference between groups C and D (P = 0.026). No side-effects of the drug were noted, nor was any adverse reaction reported from any patient. CONCLUSION: These results show a significant advantage for adjuvant intravesical IFN alpha-2b treatment over TUR alone for the 36 months of follow up and indicate that IFN alpha-2b can modify the clinical course of superficial TCC at least in the short term. The appropriate dose was apparently 80 MU, for although 40 MU was better than TUR alone, it was less effective than 60 MU and 80 MU; the 80 MU dose was slightly better than 60 MU and thus this regimen is recommended.

Administration, Intravesical↗
PubMed1998

Back propagation neural network in the discrimination of benign from malignant lower urinary tract lesions.

PURPOSE: We investigated the potential value of morphometry and artificial intelligence tools to discriminate between benign and malignant lower urinary tract lesions. MATERIALS AND METHODS: The lesions included lithiasis in 50 cases, inflammation in 61, benign prostatic hyperplasia in 99, carcinoma in situ in 5, and grade I and grades II and III transitional cell carcinoma of the bladder in 71 and 184, respectively. Images of routine processed voided urine smears stained by the Giemsa technique were analyzed using a custom image analysis system, providing a data set of 45,452 cells. A neural net model of the back propagation type was used to discriminate benign from malignant cells based on the extracted morphometric and textural features. Data from 13,636 randomly selected cells (30% of the total data) were used as a training set and the data from the remaining 31,816 cells comprised the test set. In a similar attempt to discriminate at the patient level data on 30% of those randomly selected were used to train a back propagation neural net and data on the remaining 329 were used for testing. RESULTS: Application of the back propagation neural net enabled the correct classification of 95.34% of benign and 86.71% of malignant cells with overall 90.57% accuracy. At the patient level the back propagation neural net enabled the correct classification of 100% of those with benign and 94.51% of those with malignant disease with overall 96.96% accuracy. CONCLUSIONS: The use of neural nets and image morphometry may increase the speed of cytological diagnosis and the diagnostic accuracy of voided urine cytology.

Carcinoma in Situ↗
PubMed1998

Management of renal colic with intranasal desmopressin spray.

This study evaluates the effectiveness of desmopressin renal spray, an antidiuretic drug, in treating patients with acute renal colic. One hundred and eight patients admitted to the emergency room of our hospitals with acute renal colic were included in the study. Each patient, except those with hypertension or other cardiac insufficiency, received 40 micrograms desmopressin intranasal spray. In 58 patients (53.7%) pain was eliminated 30 min after desmopressin administration. Forty-four patients (40.7%) did not respond to desmopressin and received prostaglandin synthesis inhibitors, while another 6 patients required intramuscular pethidine for pain relief. No patient showed any side effects. We conclude that the simplicity and effectiveness of intranasal desmopressin spray in treating renal colic makes this simple method a useful means of confronting a frequent and disturbing urological problem.

Administration, Intranasal↗
PubMed1997

Experience in 3,500 patients with urinary stones treated with the Dornier HM-4 bath-free lithotriptor.

During a 3-year period, hundreds of patients underwent ESWL treatment with the Dornier HM-3 and HM-4 lithotriptors operating at our institution. Our experience in 3,500 patients treated with the HM-4 bath-free lithotriptor is reported. Patients with radiolucent or cystine stones, stones larger than 3 cm or staghorn calculi, multiple stones with a total burden of more than 3 cm and those not amenable to follow-up were excluded from the study. The overall stone-free rate was 70.7% and 81% at 1 and 3 months, respectively. The stone-free rates at 1 and 3 months were further determined by the exact location of each stone within the urinary tract. Stone-free rates at 3 months ranged from 90.84% for renal pelvic stones to 71.08% for lower calyceal stones, while the stone-free rates for ureteral calculi ranged from 80.85% for upper third unstented ureteral stones to 92.92% for lower ureteral stones. The overall complication rate was 6.02% with a 1.2% post-ESWL intervention rate (ureteroscopy or placement of percutaneous nephrostomy or stent).

Disease-Free Survival↗
PubMed1997

Duodenal obstruction caused by pancreatic head carcinoma: palliation with self-expandable endoprostheses.

BACKGROUND: The risks of palliative operative intervention of gastric outlet obstruction for advanced pancreatic head carcinoma has been reported to be quite high. The present study reports the results of attempted endoscopic palliation of duodenal obstruction in these patients. METHODS: Ten patients with endoscopically documented malignant duodenal strictures from pancreatic head carcinoma in whom self-expandable endoprostheses were placed are retrospectively analyzed. In three patients with jaundice, biliary stents were also placed. Standard esophageal type (not membrance coated) Wallstent self-expandable endoprostheses were used. PATIENTS: Gastric outlet obstruction was relieved in all patients after implantation of duodenal endoprostheses, and jaundice was palliated in those with additional biliary obstruction after bile duct stenting. One case of gastric ulceration was the major complication. No recurrence of gastric outlet obstruction was noted in the follow-up period of 1 to 5 months. CONCLUSION: The preliminary data suggest that self-expandable duodenal endoprostheses can effectively relieve gastric outlet obstruction in patients with advanced pancreatic head carcinoma.

Aged↗
PubMed1997

Oral estramustine and oral etoposide for hormone-refractory prostate cancer.

OBJECTIVES: Estramustine and etoposide have been shown to inhibit the growth of prostate cancer cells in experimental models. An in vivo synergism of the two agents, when administered to patients with metastatic prostate cancer refractory to hormone therapy, has been reported. To confirm these results, we administered this combination to a large number of patients with hormone-refractory prostate cancer (HRPC). METHODS: Fifty-six patients with metastatic HRPC were treated with oral estramustine 140 mg three times a day and oral etoposide 50 mg/m2/day for 21 days. Therapy was discontinued for 7 days and the cycle was then repeated. Therapy was continued until evidence of disease progression or unacceptable toxicity occurred. To control for the possible interference of an antiandrogen withdrawal effect, all patients discontinued antiandrogen therapy and were not enrolled in the study unless there was evidence of disease progression. RESULTS: Forty-five percent of 33 patients with measurable soft tissue disease demonstrated an objective response, which included five complete and ten partial responses. Among 52 patients with osseous disease 17% showed improvement and 50% showed stability of bone scan. Thirty patients (58%) demonstrated a decrease of more than 50% in pretreatment prostate-specific antigen (PSA) levels. The median survival of all patients was 13 months. Good pretreatment performance status, measurable disease response, improvement or stability of bone scan, and PSA response were important predictors of longer survival. CONCLUSIONS: We conclude that the combination of estramustine and etoposide is an active and well-tolerated oral regimen in HRPC.

Adenocarcinoma↗
PubMed1997

Extracorporeal shock wave lithotripsy of radiolucent urinary calculi using the Dornier HM-3 and HM-4 lithotriptors.

Between September 1992 and June 1995, 33 patients with radiolucent urinary calculi were treated in our hospital using Dornier HM-3 and HM-4 lithotriptors. There were 11 caliceal stones, 13 in the renal pelvis, and 9 in the ureter. Stone localization was achieved in only 30 patients using intravenous urography or retrograde urography through a ureteric catheter during the procedure. All patients were treated on an outpatient basis, without anesthesia. During the 1st month following extracorporeal shock wave lithotripsy, the patients received alkalization. The overall stone-free rate at 3 months was 90%. The time of radiation exposure was in the range of the opacified stones. Extracorporeal shock wave lithotripsy using Dornier HM-3 and HM-4 lithotriptors proved to be an effective procedure to treat radiolucent urinary calculi when localization of the stone is possible.

Female↗
PubMed1997

Determination of interferon-alpha receptors in urothelial cancer and in normal urothelium.

PURPOSE: We determined and compared the presence and frequency of interferon-alpha 2b receptors in urothelial neoplasms and normal urothelium, since the biological activity of interferons becomes apparent only after they bind to specific receptors. MATERIALS AND METHODS: With our method detection of interferon-alpha 2b receptors required a large number of cells, that is more than 1 x 10(6) cells per ml. We studied 14 patients with relatively large tumors of all stages and grades. Three patients had grade I, 4 grade II and 7 grade III disease. As controls we used biopsies of normal urothelium from 14 patients who underwent transvesical prostatectomy. Interferon-alpha 2b receptors were detected quantitatively through the binding of radiolabeled 125iodine human recombinant interferon-alpha 2b in normal and malignant urothelial tissue samples. The interferon-alpha 2b receptors are expressed as receptor sites per cell, and the results were evaluated with Scatchard analysis. RESULTS: The number of interferon-alpha 2b receptor sites per cell ranged from 43 to 100 (mean plus or minus standard deviation 62 +/- 18) in normal urothelium and from 110 to 210 (mean 174 +/- 25) in malignant epithelium. This difference was statistically significant (p < 0.001), Student's t test 13.75). The difference in the number of interferon-alpha 2b receptors in grades I plus II and grade III tumors is suggestive but not statistically significant (p < 0.10, Student's t test 2.075). High grade tumors expressed greater numbers of interferon-alpha 2b receptors than low grade tumors. CONCLUSIONS: The method used needs refining so that it will require fewer cells to determine interferon-alpha 2b receptors. Interferon-alpha 2b receptors are detected in bladder urothelium and are abundant in malignant tissue with increasing frequency as tumor grade increases. If we can establish, in the future, a correlation of the number of interferon-alpha 2b receptors with the potential response of patients to intravesical instillation therapy with interferon, we might have an important prognostic method for selecting subgroups of patients with transitional cell carcinomas who will benefit from interferon-alpha 2b instillation.

Carcinoma, Transitional Cell↗
PubMed1997

Cisplatin, ifosfamide, methotrexate and vinblastine combination chemotherapy for metastatic urothelial cancer.

PURPOSE: We investigated the activity of combination chemotherapy consisting of cisplatin, ifosfamide, methotrexate and vinblastine in patients with metastatic urothelial cancer. MATERIALS AND METHODS: A total of 32 consecutive patients was treated with 30 mg./m.2 cisplatin on days 1 through 3, 1.5 gm./m.2 ifosfamide with mesna on days 1 through 3, 30 mg./m.2 methotrexate and 3 mg./m.2 vinblastine on day 1 plus 5 micrograms./kg. granulocyte colonystimulating factor on days 7 through 11. Courses were repeated every 21 days for a maximum of 6 cycles. RESULTS: Major toxicity was granulocytopenia in 56% of patients, including 11 episodes of granulocytopenic fever. Anemia and thrombocytopenia developed in a third of the cases. No other significant toxicity or treatment related death was noted. An objective response was achieved in 20 patients (62.5%, 95% confidence interval 44 to 79). Median time to progression was 7 months and median survival was 13 months. CONCLUSIONS: The cisplatin, ifosfamide, methotrexate and vinblastine regimen appeared active in patients with metastatic urothelial carcinoma. This regimen was associated with significant but manageable hematological toxicity and the incidence of mucositis or renal impairment was low. Prospective randomized studies are needed to assess whether the addition of ifosfamide to other active agents will improve the survival of patients with this disease.

Adenocarcinoma↗
PubMed1996

One-session bilateral ureteroscopy: is it safe in selected patients?

The aim of this study was to investigate the possibility to perform bilateral ureteroscopy in one session and to determine the procedure's indications and complication rate. Twenty-two patients underwent bilateral ureteroscopy in one session. Eighteen patients had bilateral lithiasis of the lower ureteral third, three patients had unexplained haematuria and one had unexplained bilateral hydronephrosis. The rigid ureteroscope was used in cases with stones and the flexible one in cases with haematuria and hydronephrosis. Ureteral catheters were placed in all patients. The overall stone-free rate was 83.3%. The procedure failed to confirm a diagnosis in 2 patients with unexplained haematuria. Follow-up included IVU and retrograde cystogram 3 months after the procedure and a renal scan one year later. No major complication was observed. It is concluded that bilateral ureteroscopy in one session can be performed safely in selected patients. The method does not yield major complications and saves patients from a second procedure and a second anaesthesia.

Adult↗
PubMed1996

Distal ureteral calculi: ureteroscopy vs. ESWL. A prospective analysis.

Two groups of 50 consecutive patients each, with distal ureteric calculi, were treated by ureteroscopy or in situ ESWL (Dornier HM-4 lithotriptor) in order to establish the effectiveness of ESWL at the distal portion of the ureter. In comparison to ureteroscopy, ESWL for distal ureteral calculi was performed on an outpatient basis, required less time, patients had more rapid convalescence and the procedure was simpler and safer. The overall success rate was 100% for ureteroscopy and 92% for ESWL. Our observations showed that in situ ESWL with the Dornier HM-4 lithotriptor is the method of choice for the treatment of distal ureteral calculi.

Adult↗
PubMed1996

Primary renal lymphoma: a clinical and radiological study.

PURPOSE: We assessed the incidence, clinical and radiological features, and prognosis of patients with renal lymphoma. MATERIALS AND METHODS: We studied 210 patients with symptoms, signs and and radiological findings suggestive of renal cell carcinoma. RESULTS: Final diagnosis in 6 of 210 patients (3%) was primary renal lymphoma. Radiological features were similar to those of renal cell carcinoma. Five of the 6 patients had an International Prognostic Index score of greater than 1. Despite appropriate chemotherapy, only 2 patients remain with complete remission. CONCLUSIONS: Primary renal lymphoma is unusual but not rare. The relatively poor prognosis in our patients could be attributed to the adverse prognostic factors associated with aggressive nodal lymphomas.

Aged↗
PubMed1996

Palliation of malignant gastric outlet obstruction with self-expanding metal stents.

BACKGROUND AND STUDY AIMS: Self-expanding metal stents have long been used in the management of patients with malignant esophageal and malignant biliary obstruction. The aim of the present study was to report on the palliation of malignant gastric outlet obstruction using self-expanding endoprostheses. PATIENTS AND METHODS: Between March 1993 and December 1994, 12 patients (eight women, four men, mean age 64 years) suffering from malignant gastric outlet obstruction due to recurrent gastric carcinoma (seven patients) and pancreatic head carcinoma (five patients) presented with an inability to eat and intractable vomiting. The patients were managed with peroral insertion of self-expanding metal stents. RESULTS: Peroral introduction of the stent with the aid of a stabilizing overtube was successful in all patients, with the stent being supported as it was being advanced through the stenosis. Proper release of the stent into the stenotic area was achieved in all cases, relieving the intractable vomiting. The procedure was accomplished without any complications. All patients were able to eat semisolid food four days after the stent insertion. Apart from an asymptomatic partial stent occlusion in one patient, no other complications were seen during the short-term follow-up one, two, and three months after discharge. CONCLUSIONS: These preliminary results suggest that self-expanding stents can effectively relieve malignant gastric outlet obstruction.

Aged↗
PubMed1996

Palliation of large-bowel obstruction due to recurrent rectosigmoid tumor using self-expandable endoprostheses.

When large-bowel obstruction supervenes in patients with rectal tumor recurrence and extensive nonresectable disease, a proximal diverting colostomy may be indicated. In this study, nonsurgical palliation of the obstruction was attempted by inserting self-expandable endoprostheses to bridge the stenotic lesion. The endoprostheses were positioned in two patients with large-bowel obstruction due to recurrent stenotic tumor, and extensive disease excluding palliative resection. Self-expandable endoprostheses with inner diameters of 18 mm and 22 mm were successfully inserted under endoscopic and radiographic control. Proper expansion of the endoprostheses was achieved in both patients, resulting in immediate decompression of the bowel and lasting relief of the obstruction.

Aged↗
PubMed1996

Extracorporeal shock wave lithotripsy of middle ureteral calculi: ventral shock wave application.

A total of 150 patients presenting with stone in the middle iliac ureter were treated with extracorporeal shock wave lithotripsy using a Dornier HM-4 lithotriptor. For adequate radiological stone visualization and excellent fragmentation, the prone position was used in all patients. In 45 patients (30%) an ureteral stent was placed before treatment. The overall success rate was 82% (123 of 150 patients). All patients were treated on an outpatient basis without anesthesia.

Adult↗
PubMed1996

Extracorporeal shock wave lithotripsy for renal stones in children.

The aim of our study is to determine the efficacy and safety of extracorporeal shock wave lithotripsy (ESWL) as a method of treatment of nephrolithiasis in childhood. Between 1986 and 1994, 50 children with renal calculi were treated by ESWL in our department. The age of the children ranged from 8 months to 14 years. Thirty-three of them were boys and 17 girls. The stone location was in the renal pelvis in 38 cases, in the upper renal calyx in 4 cases, in the lower calyx in 2, while 6 children had staghorn calculi. The stone size ranged between 3 and 39 mm. All treatments were performed with Dornier HM4 except 12 children, all older than 10 years, who underwent ESWL with Dornier HM3. All ESWL procedures took place under general anesthesia or sedation with ketamine. The number of shock waves varied between 400 and 2,000 per treatment and the standard maximum generator voltage was 18 kV. The overall stone clearance rate at 1 month was 66%. Fourteen children with large residual fragments underwent a second ESWL procedure 3 months later. With a mean follow-up of 33 months, 41 children (82%) are stone-free. Ten children developed urinary tract infection and 5 Steinstrasse. Twelve children had a pre- and post-ESWL DMSA scan and no permanent impairment of renal function was observed. We conclude that ESWL is the treatment of choice for urinary tract lithiasis in childhood. It is a low-risk method, without serious complications, which yields as high a success rate in children as in adults. We believe that as the stone fragmentation and clearance is much higher in children that in adults, the method must be the initial approach and may be the monotherapy even in staghorn or complex stones.

Adolescent↗