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Biomedical subjects

B Dufour

Publications and source records attributed to B Dufour.

At least 55 records · Page 3Linked to original sources
PubMed1994

Serum tissue polypeptide antigen (S-TPA) in bladder cancer as a tumor marker. A prospective study.

BACKGROUND: Tissue polypeptide antigen (TPA) is a differentiation and a proliferation tissue marker of non-squamous epithelia. Increased urinary and serum TPA (S-TPA) levels were found in some patients with invasive bladder cancer. The authors report the results of a prospective study evaluating the role of serum TPA (S-TPA) in bladder carcinoma. METHODS: S-TPA concentrations were measured by radioimmunoassay in 53 patients with invasive bladder tumor before treatment, at the end of treatment, and during follow-up. The upper normal limit of the test was set at 80 UI/ml. RESULTS: With a specificity of 100%, the diagnostic sensitivity of the test was 54.7%. S-TPA was increased in 88% of patients with N1 + N2 disease compared with 38.8% of the patients with N0 disease (P = 0.01) and in 100% of patients with metastatic disease and 48% of patients with nonmetastatic disease (P = 0.01). S-TPA was increased in 23% of patients with total macroscopic debulking and in 68% of patients with persistent macroscopic disease (P = 0.004). For patients staged N0 M0, no statistical correlation between S-TPA level and debulking by transurethral resection (TUR) was found (P = 0.15). In the subset of patients with normal pretherapeutic S-TPA levels, 75% achieved a complete response, compared with 44.8% of the patients with initial elevated S-TPA levels (P = 0.04). However, there was no statistically significant relationship between pretherapeutic S-TPA levels and immediate response to treatment according to the stratification for tumor volume after initial debulking by TUR. For a mean follow-up of 15 months +/- 7 months, median survival time and 1-year survival rates were studied in the subset of patients with limited disease (N0 M0) according to the pretherapeutic S-TPA levels. The median survival time was not reached, and the 1-year survival rate was 80% when the initial S-TPA level was normal; these were 10 months and 44%, respectively, when the S-TPA level was high (P < 0.01). Among the 31 patients who achieved a complete response, 9 experienced a relapse, with an increase of the S-TPA level in 8 patients. CONCLUSIONS: The S-TPA level is correlated with initial tumor volume. It appears to be a prognostic factor and a valuable parameter for follow-up.

Biomarkers, Tumor↗
PubMed1994

[MRI in cancer of the prostate with T1-weighted sequences using fat suppression and injection of gadolinium].

The assessment of tumor extension in 20 patients with cancers of the prostate at a clinical stage A or B included MRI with a body coil before prostatectomy. Transverse and coronal T1-weighted sections with injections of gadopentate dimeglumine (gadolinium) and fat suppression were systematically taken to assess the vascularity of the various regions of the prostate and of the cancer, as well as the merits of such sequences for the assessment of extension. The normal, poorly vascularized peripheral area is only slightly enhanced by injection, while the transition area, which is most often hyperplastic in the age group studied, enhances heterogeneously with contrast. All cancers enhance after injection. In the assessment of extension, the major merit of gadolinium is that it allows exploration both of the vesiculodeferential junction on coronal sections and of the structure of the seminal vesicles. Thus a normal junction allows ruling out macroscopic invasion of the vesicles. In addition, gadolinium allows correcting false positive MRI findings when the areolar structure of the vesicles is preserved. Gadolinium does not provide additional evidence of extension through the capsule in comparison with T2-weighted sequences. On a whole, in our series, MRI with a body coil, associated T2-weighted sequences and T1-weighted sequences after gadolinium injection and fat suppression, has 58% sensitivity and 100% specificity for the diagnosis of stage C cancers.

Aged↗
PubMed1993

Combined radiation and chemotherapy for invasive transitional-cell carcinoma of the bladder: a prospective study.

PURPOSE: To improve the results obtained by cystectomy alone and to determine the possibilities of conservative treatment in invasive bladder cancer, we designed a prospective study using a combination of fluorouracil (5-FU) plus cisplatin and concomitant radiation therapy, followed by either cystectomy or additional chemoradiotherapy. PATIENTS AND METHODS: Fifty-four patients with stage T2 to T4 operable untreated invasive bladder cancer were entered onto the study. Treatment was begun in all patients by transurethral resection (TUR) and followed by the 5-FU-cisplatin combination with concomitant bifractionated split-course radiation therapy. A control cystoscopy was performed 6 weeks after completion of the neoadjuvant program. Patients with persistent tumor underwent cystectomy. Complete responders were treated by either additional chemoradiotherapy (group A) or cystectomy (group B). RESULTS: At control cystoscopy, 40 of 54 patients (74%) had a histologically documented complete response. Four responders developed recurrent pelvic disease after a mean follow-up time of 27 +/- 12 months (three in group A and one in group B). Metastatic disease, which developed in 16 patients, occurred more frequently in the nonresponders (71%) than in responders (15%). The disease-free survival rate at 3 years was 62%; it was significantly better in responders (77%) than in nonresponders (23%). There was no difference in survival between groups A and B. CONCLUSION: This neoadjuvant chemoradiotherapy combination, easy to implement and well tolerated even in elderly patients, provides a high complete response rate. It may prove to be effective in inoperable patients and may be proposed as conservative treatment in patients with a complete response to the initial course of chemoradiation.

Adult↗
PubMed1993

[Uretero-uterine fistula. Diagnostic and therapeutic management].

A case of uretero-uterine fistula leads the authors to analyse the possible causes and review the diagnosis approach, which is above all clinical:incontinence of urine with persistence of normal micturition; leakage of urine via the cervix and cystoscopically normal bladder, most often following cesarean section. Treatment possibilities are considered, with uretero-vesical reimplantation having a place of choice.

Adult↗
PubMed1993

[Methodology of surveys in animal epidemiology].

In the present paper, the authors review the methodological bases of surveys, both descriptive and analytical, used in animal epidemiology. They give a comprehensive definition of the main terms applied to epidemiology as well as of the method used to evaluate the quality of these surveys.

Animal Diseases↗
PubMed1993

[Role of MRI in the diagnosis of kidney cancer].

The recent technical developments in magnetic resonance imaging (MRI) and the use of paramagnetic contrast media (gadolinium compounds) have considerably improved the performances of MRI for the detection and characterization of renal tumors. MRI does not have specific merits for the diagnosis of the typical form of cancer, nor for the detection of small kidney tumors, both being mainly based on computed tomography (CT). On the other hand, it can be used for the diagnosis of atypical forms of cancers (small, hypovascular, cystic or hemorrhagic cancers) which raise problems of differential diagnosis with some pseudotumoral lesions, complex cysts and benign tumors. Its complementarity to CT for the characterization of an atypical mass results from the signal information it provides, from a better contrast resolution, and from the possibility to make sections in all planes of space. Except for angiomyolipoma, which has a fatty content, there is no really specific MR criterion as present to evidence benign renal tumors. Concerning regional extension, CT remains the primary technique of choice, as it allows studying the limits of the tumor, the renal compartment ans its walls, the renal vein and the inferior vena cava, the neighboring organs and the contralateral kidney all together. Its findings allow defining the indications of MRI, which, as a complementary exploration, is often decisive to assess venous invasion.

Diagnosis, Differential↗
PubMed1992

Fluoroscopically guided percutaneous transrenal electroincision of ureterointestinal anastomotic strictures.

A new technique for electroincision of a strictured ureterointestinal anastomosis is described that uses a sphincterotome and high frequency current. After placement of a percutaneous nephrostomy tube a 7F "wire guided" sphincterotome was placed into the stenosis. The cutting wire was then deflected while cutting current was applied intermittently. Injection of contrast medium through the papillotome probe assessed the depth of the incision. A 10 mm. angioplasty balloon was inflated at low pressure to verify that the anastomosis had been incised to a depth of 1 cm. The anastomosis was then stented for 8 weeks with an 18F stent. The operative time did not exceed 45 minutes. A total of 9 stenoses was treated in 7 patients: 4 were ileal conduit diversions and 5 were enterocystoplasties. No immediate complication was observed. In 1 case a small urinoma was surgically drained at removal of the stent. Six stenoses are patent with 2, 3, 4, 4, 10 and 13 months of followup after removal of the stent. One patient died of bladder tumor metastases during the stenting period and 1 with bilateral incision still has a stent. The technique can be performed without major complication (bleeding or digestive fistula). Long-term results remain to be assessed.

Constriction, Pathologic↗
PubMed1992

[What may be expected from endorectal echography and magnetic resonance imaging in the evaluation of local extension of cancer of the prostate?].

Thirty patients presenting with a clinical stage A or B cancer underwent TRUS and MRI with a body coil prior to radical prostatectomy. Imaging and pathology were correlated to assess the limits of TRUS and MRI in pre-operative staging of prostatic carcinoma. Results showed that TRUS and MRI had a sensitivity of 42 and 66% and a specificity of 89 and 94% respectively, for the diagnosis of macroscopic capsular effraction. Seminal vesicle invasion was diagnosed by TRUS with a sensitivity of 16% and a specificity of 81%. With MRI, the sensitivity and the specificity were 85 and 94% if only gross infiltration was considered. Sensitivity dropped to 45% if microscopic invasion was included. We conclude that: 1) postero-lateral venous plexus are more easily delineated by MRI, permitting a more accurate diagnosis of capsular penetration. 2) Seminal vesicle invasion cannot be diagnosed by TRUS as the echo-structure of the cancer and the caudal junction of the seminal vesicles and vas deferent are similar. 3) A normal caudal junction on TRUS or a normal bilateral hypersignal of the seminal vesicles on MRI are associated with seminal vesicle invasion in less than 5% of cases. 4) A normal caudal junction on TRUS eliminates false positive cases of MRI related to non tumoral hyposignals of the seminal vesicles.

Aged↗
PubMed1992

[Desmoid tumor of the mesentery. An uncommon cause of ureteral obstruction].

Desmoid tumors are rare lesions with a local invasive potential and a risk of recurrence considered as benign due to the absence of metastases. They are included in fibromatoses and may be associated with Gardner's syndrome. The authors report an unusual case, in a 26 year old man, of a desmoid tumor invading ileon, right colon, appendix and the right ureter and responsible of a ureteral obstruction. Etiologic factors (traumatic, hormonal, auto-immune...) are discussed. The treatment of choice to lower the risk of recurrence is the complete surgical removal of the tumor.

Adult↗
PubMed1992

[Role of MRI in the diagnosis of cancer of the kidney].

The recent technical developments in magnetic resonance imaging (MRI) and the use of paramagnetic contrast media (gadolinium compounds) have considerably improved the performances of MRI for the detection and characterization of renal tumors. MRI does not have specific merits for the diagnosis of the typical form of cancer, nor for the detection of small kidney tumors, both being mainly based on computed tomography (CT). On the other hand, it can be used for the diagnosis of atypical forms of cancers (small, hypovascular, cystic or hemorrhagic cancers) which raise problems of differential diagnosis with some pseudotumoral lesions, complex cysts and benign tumors. Its complementarity to CT for the characterization of an atypical mass results from the signal information it provides, from a better contrast resolution, and from the possibility to make sections in all planes of space. Except for angiomyolipoma, which has a fatty content, there is no really specific MR criterion as present to evidence benign renal tumors. Concerning regional extension, CT remains the primary technique of choice, as it allows studying the limits of the tumor, the renal compartment and its walls, the renal vein and the inferior vena cava, the neighboring organs and the contralateral kidney all together. Its findings allow defining the indications of MRI, which, as a complementary exploration, is often decisive to assess venous invasion.

Adenocarcinoma↗
PubMed1991

[Color and pulsed Doppler of renal masses. Angiographic and anatomo-pathological correlation].

We report the results of a prospective study about the detection of tumoral neovascularization, the renal vein involvement and the characterization of renal tumors by color and pulsed doppler. Twenty-six renal tumors including 19 renal carcinomas and 7 benign tumors (2 angiomyolipomas, 2 oncocytomas, 2 complex cysts and one adenoma) were prospectively explored. Benign cysts were excluded from the study. The results were correlated to pathologic (24/26) and angiographic datas (24/26). Doppler ultrasonography seems to be an accurate method for the detection of a neovascularization (19 true-positives/19 vascularised tumors, no false-positive) but pulsed doppler (no false-negative) is more sensitive than color doppler imaging (3 false-negatives), the results of color doppler were improved by using a new software for the color detection of very low flow. Spectral analysis found 3 different types of doppler curves inside the masses, but all of them were observed in benign and malignant tumors. We did not find any correlation between the size of the tumor and the peak systolic velocity. The specificity of Doppler regarding the renal vein and inferior vena cava involvement seems to be good (no false-positive). But as, in our series, we do not have any case of main renal vein involvement, the sensitivity of this technique cannot be assessed.

Adult↗
PubMed1991

[What may be expected from endorectal ultrasonography and magnetic resonance imaging in the assessment of local extension of cancer of the prostate?].

30 patients presenting with a clinical stage A or B cancer underwent TRUS and MRI with a body coil prior to radical prostatectomy. Imaging and pathology were correlated to assess the limits of TRUS and MRI in pre-operative staging of prostatic carcinoma. Results showed that TRUS and MRI had a sensitivity of 42 and 66% and a specificity of 89 and 94% respectively, for the diagnosis of macroscopic capsular effraction. Seminal vesicle invasion was diagnosed by TRUS with a sensitivity of 16% and a specificity of 81%. With MRI, the sensitivity and the specificity were 85 and 94% if only gross infiltration was considered. Sensitivity dropped to 45% if microscopic invasion was included. We conclude that: (1) postero-lateral venous plexus are more easily delineated by MRI, permitting a more accurate diagnosis of capsular penetration. (2) Seminal vesicle invasion cannot be diagnosed by TRUS as the echostructure of the cancer and the caudal junction of the seminal vesicles and vas deferens are similar. (3) A normal caudal junction on TRUS or a normal bilateral hypersignal of the seminal vesicles on MRI are associated with seminal vesicle invasion in less than 5% of cases. (4) A normal caudal junction on TRUS eliminates false positive cases of MRI related to non tumoral hyposignals of the seminal vesicles.

Aged↗
PubMed1991

[Desmoid tumor of the mesentery. An uncommon cause of ureteral obstruction].

Desmoid tumors are rare lesions with a local invasive potential and a risk of recurrence considered as benign due to the absence of metastases. They are included in fibromatoses and may be associated with Gardner's syndrome. The authors report an unusual case, in a 26 year old man, of a desmoid tumor invading ileon, right colon, appendix and the right ureter and responsible of a ureteral obstruction. Etiologic factors (traumatic, hormonal, auto-immune, ... ) are discussed. The treatment of choice to lower the risk of recurrence is the complete surgical removal of the tumor.

Adult↗
PubMed1991

[Conservative surgery of kidney cancer. Ex vivo surgery with immediate magnetic resonance imaging].

In addition to the technical difficulties arising when the tumor is located in the centre of the kidney, one of the stumbling blocks of conservative partial surgery of the parenchyma is the risk of leaving a second tumoral focus in place. In these cases, we propose an ex vivo operation associated with an intraoperative examination of the isolated kidney with nuclear magnetic resonance.

Anastomosis, Surgical↗