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BHD, TP53, and HNF1beta on chromosome 17 were studied in 92 cases of renal cell carcinoma (46 chromophobe, 19 clear cell, 18 oncocytoma, and nine papillary). Six, thirteen, and zero cases had, respectively BHD, TP53, and HNF1beta mutations, (84% mutations involved chromophobe), suggesting a role for BHD and TP53 in chromophobe subtype.
BACKGROUND: Lamivudine is a potent inhibitor of human immunodeficiency virus reverse transcriptase and hepatitis B virus (HBV) DNA polymerase. Its overall efficiency is clearly hampered by relapse at discontinuation and by risk of genotypic resistance. We describe herein the first cases of HBV resistance to lamivudine in kidney recipients and hemodialyzed patients. METHODS: We analyzed 26 HBV-infected kidney recipients and five hemodialyzed patients treated with lamivudine who became serum HBV DNA-negative (by Digene test). The biological and virological follow-up identified breakthrough as defined by the reappearance of serum HBV DNA. In two cases of breakthrough, HBV DNA was amplified and sequenced through the polymerase domain, including the YMDD motif, before the beginning of treatment and at time of breakthrough to determine genotypic mutations. RESULTS: Ten breakthroughs (reappearance of serum HBV DNA) were observed after a median follow-up of 11 months in eight kidney recipients and two hemodialyzed patients after a median duration of treatment of 16.5 (from 4 to 31) months of treatment. Previous HBe/anti-HBe seroconversion was not observed in the patients who escaped. In two kidney recipients, the comparison of HBV-DNA sequences before the treatment and after the breakthrough identified in one case a mutation of the highly conserved YMDD motif (YVDD), whereas in the second case, no genotypic mutation was observed in the sequenced region. CONCLUSION: We report the first cases of HBV genotypic resistance to lamivudine in kidney recipients and hemodialysis patients. Genotypic resistance is observed after 4-31 months of therapy. The YMDD mutation does not account for all cases of virological escape.
AIMS: Renal lesions in von Hippel-Lindau disease comprise clear cell simple cysts, atypical cysts and carcinomas. Although histological and molecular studies suggest that cystic lesions may represent precursors of carcinomas, there is no detailed phenotypic evidence of their relationship. METHODS AND RESULTS: To investigate such a possible relationship between cystic lesions and solid carcinomas, we studied the pathological and immunohistochemical features of 328 lesions of 33 kidneys originating from 23 patients with von Hippel-Lindau disease, using a panel of antibodies directed against cytoskeleton proteins, cell surface proteins, integrin subunits, adhesion molecules, lectins, and apoptosis and proliferation markers. Solid carcinomas (n = 175) were all of clear cell type and mostly nuclear grade 1. Cystic lesions (n = 138) consisted of cystic clear cell carcinomas (n = 15), atypical cysts (n = 20) and simple cysts (n = 103). Clear cells of the simple cysts, atypical cysts and solid carcinomas coexpressed cytokeratins (CK8, CK19) and vimentin, and expressed a similar pattern of tubular markers (CD24, tetraglonolobus), integrin subunits (alpha3, alpha5, alpha6, alphav, beta1) and cell adhesion molecules (ICAM 1, VCAM 1). In all lesions studied, proliferation rate (MIB1 index) was low, and apoptosis marker expression (fragmented DNA, p53, bcl-2) inconspicuous. CONCLUSIONS: Phenotypic alterations found in solid renal cell carcinomas are already present in simple and atypical renal cysts of von Hippel-Lindau disease.
BACKGROUND: Ursodeoxycholic acid (UDCA) could potentiate the effect of interferon (IFN) in patients with chronic hepatitis C resistant to IFN. We compared the efficacy of IFN with that of a combination of IFN and UDCA. METHODS: Patients were randomized to receive UDCA (13-15 mg/kg/day) (n = 47) or placebo (n = 44) plus interferon (3 MU three times weekly) for 6 months and were then followed up for 6 additional months. RESULTS: At entry 30% of patients had cirrhosis, and 70% had HCV genotype 1. Five and four patients withdrew from the combination and the monotherapy groups, respectively. At 6 months alanine aminotransferase (ALAT) and gamma-glutamyl transferase (GGT) activities were significantly lower (P < 0.001) in the combination group than in the monotherapy group; the differences were no longer significant at 1 year. At 6 months ALAT activities normalized in 10 and 8 patients in the combination and the monotherapy groups, respectively (P = 0.67). In 10 of them (5 in each group) HCV RNA levels became undetectable. At 1 year four versus one patient had a sustained normalization of ALAT, and in one patient the HCV RNA became negative. There was no difference in the histologic progression. In this setting, in contrast to chronic cholestasis, UDCA administration induced an increase in total serum bile acids and did not change primary bile acids. CONCLUSIONS: An IFN plus UDCA combination is more effective than IFN alone in terms of ALAT but not in terms of the virologic response. These results favor the hypothesis that UDCA has an effect on the biochemical indices of cellular injury independent of a change in primary bile acids.
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PURPOSE: To describe the technique and results of incision of strictures in anastomotic urinary diversions with a commercially available cutting balloon catheter. MATERIALS AND METHODS: Thirty-seven stenoses were treated in 32 patients. Most (28 [88%]) of the patients had undergone surgery for bladder cancer 17.7 months +/- 17.4 (SD) (range, 3-72 months) before incision. Thirteen patients had undergone ileal conduit diversion, and nineteen had undergone enterocystoplasty. All stenoses were shorter than 3 cm. The presence of adjacent ileal loops and/or iliac vessels was assessed with computed tomography before incision. The cutting wire was oriented anteriorly or anterolaterally, and the balloon was inflated with diluted contrast material during the incision. A Kaplan-Meier survival curve was constructed to illustrate the success rates over time. RESULTS: No major complications occurred. Twelve (32%) stenoses recurred in nine patients 15 months +/- 10 (range, 6-36 months) after stent removal; the failure rate was 53% (eight of 15 stenoses) for ileal conduits and 18% (four of 22 stenoses) for enterocystoplasties. Late failure (>12 months) was observed in four patients. The patency of the other 25 stenoses (23 patients) was checked 25 months +/- 11 after stent removal (range, 5-43 months). The actuarial patency rate was 77% at 1 year, 68% at 2 years, and 62% at 3 years. CONCLUSION: Cutting balloon incision is a safe and simple alternative to surgery, particularly when the urinary diversion is enterocystoplasty.
OBJECTIVE: The purpose of this study was to describe endorectal sonography and color Doppler sonography features of nonpalpable prostate cancer and to assess the value of endorectal MR imaging for the preoperative local staging of these tumors. MATERIALS AND METHODS: Ninety-four patients with nonsuspicious findings on digital rectal examination and a mean prostate-specific antigen level of 16.3 +/-10 ng/mL (median, 13 ng/mL) underwent endorectal sonography, color Doppler sonography, sextant endorectal sonographically guided biopsy, and endorectal MR imaging before radical prostatectomy. RESULTS: Tumors were visible in 48 cases and not visible in 46. The mean Gleason biopsy score, the frequency of tumors involving three sextants or more of the prostate gland at biopsies, and the frequency of stage pT3 tumors were significantly higher in patients with visible tumors (5.9+/-0.9, 42%, and 37.5%) than in those with invisible tumors (5.4+/-1.1, 17%, and 17%). The 42 hypervascular tumors were hypoechoic in every case and had a higher rate of Gleason tumor grades 4 and 5 at biopsy than did the 52 hypovascular tumors (33% versus 11.5%). Six hypovascular tumors (6/52, 11.5%, two visible) had an insignificant tumor volume. Established extraprostatic tumor spread was detected on MR imaging in six of 18 cases (sensitivity, 33%; specificity, 100%0, all of which had the following four features: hypervascularity, prostate-specific antigen level greater than 20 ng/mL, three or more sextants of the gland having positive findings at biopsy, and seminal vesicle invasion. CONCLUSION: Endorectal sonography and color Doppler sonography are useful to differentiate low-risk invisible and hypovascular tumors from high-risk visible and hypervascular tumors. However, MR imaging has a poor sensitivity for the detection of extraprostatic spread and is accurate only in a minority of highly selected high-risk hypervascular tumors.
Several conservative operations are available for renal tumours. This article describes the anatomical bases, the measures designed to protect the parenchyma from ischaemia and the various resection techniques. Wedge resection is described in detail, as it appears to be the most rigorous technique.
To investigate the nature of somatic von Hippel-Lindau (VHL) mutations, we analyzed 173 primary sporadic human renal cell carcinomas for mutations of the VHL tumor suppressor gene, using polymerase chain reaction (PCR) and single-strand conformational polymorphism analysis (SSCP) of DNA. We detected abnormal SSCP pattern in 73 samples. After sequencing, we identified microdeletions in 58% of cases, microinsertions in 17%, nonsense mutations in 8%, and missense mutations in 17%. Among these mutations, 50% correspond to new mutations. VHL mutations were found only in the nonpapillary renal cell carcinoma (RCC) subtype, as previously reported. To compare somatic and germline mutations, we used the VHL database, which includes 507 mutations. The study of mutational events revealed a significant difference between somatic and germline mutations with mutations leading to truncated proteins observed in 78% of somatic mutations vs only 37% in germline mutations (P < 0.001). We postulated that a specific pattern of VHL mutations is associated with sporadic RCC. This pattern corresponds to mutations leading mainly to truncated proteins with few specific missense mutations. We then analyzed the occurrence of RCC in VHL families, based on the nature of mutations. We observed RCC in at least one member of the VHL families in 77% of cases with mutations leading to truncated proteins versus 55% in cases with missense mutations (P < 0.05). Thus, mutations resulting in truncated proteins may lead to a higher risk of RCC in VHL patients.
Ursodeoxycholic acid (UDCA) treatment has been shown to increase survival without orthotopic liver transplantation (OLT) in patients with primary biliary cirrhosis (PBC) at 4 years. Whether this beneficial effect was maintained over the long term remained to be established. In a large cohort of UDCA-treated patients with PBC, we aimed to determine the 10-year outcome of these patients using two endpoints: (1) survival without OLT, and (2) survival. The cohort was comprised of 225 patients with PBC treated with UDCA (13-15 mg/kg/d) monitored from the beginning of treatment until time of last follow-up, OLT, or death. Because of the absence of a control group, survival without OLT was compared with survival predicted by the Mayo model (first 7 years), and observed 10-year survival with an estimation of survival of a standardized control cohort of the French population. Observed survival without OLT of UDCA-treated patients was significantly higher (P <.04) than survival predicted by the Mayo model. Observed survival was significantly lower (P <. 01) than survival predicted from the French population. Observed survival of noncirrhotic patients was not different (P >.9) from that of the French control population but survival of cirrhotic patients was significantly lower (P <.0001). Twenty-two patients died; 13 patients died of hepatic causes and 4 patients died after OLT. In conclusion, survival without OLT among patients treated with UDCA for PBC is higher than that of untreated patients, as predicted by the Mayo model. Ten-year survival among UDCA-treated patients is slightly lower than that of an age- and sex-matched general population, the difference mainly being explained by mortality among cirrhotic patients.
OBJECTIVES: To describe and analyse the proposed therapeutic modalities to treat a series of patients suffering from Fournier's gangrene involving the entire scrotum. MATERIAL AND METHODS: Four patients with macroscopically identical lesions of Fournier's gangrene involving the entire scrotum were managed by wide surgical debridement, diversion colostomy, triple combination antibiotic therapy, transfer to surgical intensive care, multiple repeated operations under general anaesthesia for excision of atonic tissues and mesh skin grafts. The colostomy was closed after 4 months. RESULTS: All patients survived after skin cover. Three of them were reviewed 2 months after restoration of gastrointestinal continuity and presented a good general status with a satisfactory esthetic result. The fourth patient was lost to follow-up. The mean reoperation rate was 6.5 per patient. The mean intensive care stay was 9.5 weeks. CONCLUSION: The choice of intensive treatment depends on the extent of the lesions. When the entire scrotum is involved, repeated surgical excisions and systematic colostomy, combined with the other treatment modalities appear to be necessary to manage this disease, which still has a serious prognosis.
Until now, radical cystectomy has been considered the most effective treatment for invasive bladder cancer. However, it fails to cure more than 50% of patients and can result in a mediocre quality of life. In an effort to improve cure rates, combined modality regimens have been investigated. Despite the preliminary results of early clinical trials, randomized trials have most often failed to show any benefit from neoadjuvant or adjuvant chemotherapy or radiotherapy. One of the major progress brought by radiotherapy has been the wide use of conservative treatment in several cancer, and in the recent years promising results with concomitant radiochemotherapy have been published. Use of the conservative approach in bladder cancer now appears to be a tangible reality for selected patients, but these combined modalities have not yet been tested in randomized trials.
BACKGROUND: Renal vein thrombosis, long recognized as a classical complication of acute pyelonephritis, has become exceptional since the advent of antibiotics. CASE REPORT: An 85-year-old woman was hospitalized for acute Escherichia coli nephritis. Computed tomography with contrast agent injection was performed due to clinical improvement after an 8-day course of antibiotics and demonstrated purulent urine collection on an obstructive calicial stone as well as homolateral thrombosis of the renal vein. Duplex Doppler confirmed the diagnosis. Pulmonary embolism was evidenced by pulmonary scintigraphy. The clinical course was satisfactory after urine drainage and efficacious antibiotics. CONCLUSION: Renal vein thrombosis remains a severe though uncommon complication of acute pyelonephritis. Computed tomography with iodine, contrast agent or duplex Doppler allows noninvasive diagnosis.
The role of the viral genotype, especially genotype 1b, in the severity of liver injury induced by chronic hepatitis C virus (HCV) infection is unclear, probably because of confounding factors such as the date and mode of contamination. Host genetic or environmental factors such as heterozygous MZ alpha1-antitrypsin deficiency or alcoholism, could also be potential risk factors for the development of cirrhosis. The aim of this study was to compare the prevalence of genotypes, alpha1-antitrypsin phenotype, past hepatitis B virus infection, and alcohol consumption in cirrhotic and noncirrhotic patients with chronic hepatitis C. We conducted a case-control study comparing 84 consecutive cirrhotic patients with chronic hepatitis C (cases) with 84 noncirrhotic patients with chronic hepatitis C (controls) selected from a cohort of 464 patients hospitalized during the same period. Controls were paired with cases according to age, sex, risk factors, and date of infection. HCV genotypes were determined using the InnoLiPA technique (Innogenetics, Zwijnaarde, Belgium) and classified according to the method of Simmonds. Patients were divided in three groups according to alcohol consumption: <30 g/d (light), 30 to 80 g/d (moderate), and >80 g/d (heavy). Cirrhotic and noncirrhotic patients were not significantly different in terms of genotype distribution (1a/1b/2a/3a/others/undetermined: 10/48/7/17/0/2 versus 11/43/10/10/5/5), alpha1-antitrypsin phenotype distribution (MM/MS/MZ: 84%/14%/2% vs. 87%/11%/2%, respectively), and prevalence of antibody to hepatitis B core antigen positivity (29% vs. 23%). Alcohol consumption was significantly different between cases and controls (L/M/H: 58%/27%/16% vs. 76%/15%/9%, respectively; P < .05). Two conclusions regarding patients with chronic hepatitis C virus infection can be drawn from this study: 1) viral genotype, especially 1b, past hepatitis B virus infection, and heterozygous MZ alpha1-antitrypsin deficiency are not risk factors for cirrhosis; and 2) alcohol consumption, even moderate, is a risk factor for cirrhosis.
OBJECTIVES: To compare results of color Doppler-guided ultrasonography (CDUS) versus those of systematic biopsies in 591 patients with an elevated serum PSA level and to correlate them with digital rectal examination (DRE) findings. METHODS: Biopsies were directed into hypervascularized (CDUS+) or hypovascularized (CDUS-) hypoechoic peripheral zone nodules (443 cases). When transrectal ultrasound (TRUS) was normal (148 cases), biopsies were directed into hypervascular area. Six additional posterior biopsies were also performed in every patient, together with four anterior biopsies in 117 patients with normal DRE and prostate weight above 40 g. RESULTS: Biopsies were positive in 339 patients (57%). Positive biopsy rate (PBR) of directed biopsies was 84% in hypervascular abnormalities (264 of 316) and 17% in hypovascular nodules (23 of 134) (P < 0.001). PBR of combined biopsies was 84% in CDUS+ patients (266 of 316) and 26% in CDUS- patients (73 of 275) (P < 0.001). Comparison of TRUS and CDUS showed a sensitivity of 0.9 and 0.78, respectively, and a specificity of 0.46 and 0.8, respectively. Of the 131 patients with a PSA level between 4 and 10 ng/mL and a normal DRE, PBR was 59% (22 of 37) when CDUS was positive and 11% (10 of 94) when it was negative, regardless of TRUS abnormalities (P < 0.001). Nonpalpable cancers with a negative CDUS showed a significantly (P < 0.001) lower Gleason score (5.5 +/- 0.9) than that of CDUS+ cancer (6.5 +/- 1.1). Eleven cancers were diagnosed by only anterior positive biopsies. All of them had a negative CDUS and a PSA level above 10 ng/mL. CONCLUSIONS: CDUS does not modify prostate biopsy policy except in patients with negative CDUS, normal DRE, and PSA level between 4 and 10 ng/mL, where deferment of biopsy can be advocated. Anterior biopsies are only useful in patients with a PSA level above 10 ng/mL and a negative CDUS.
We report a french experience of subcutaneous administration of interleukin-2 in treatment of patients with metastatic renal cell carcinoma. Thirty-nine patients with metastatic renal cell carcinoma were included in the study. During the 10-week induction period, interleukin-2 was administrated subcutaneously 5 days a week for 8 weeks. The weekly dosage were 90 MIU during weeks 1 and 6; 63 MIU during weeks 2 to 4 and 7 to 9. After evaluation, responders and patients with stable disease received maintenance treatment which was discontinued upon the appearance of disease progression or unacceptable toxicity. During the maintenance period, interleukin-2 was administered 5 days a week for 4 weeks followed by a 2-week rest period. The weekly dosages were 90 MIU in week 1 and 63 MIU in weeks 2 to 4. After completion of induction treatment, 7 of 39 evaluable patients (18%) had objective responses with 1 complete response. A diminution of dose or interruption of treatment occurred with 7 patients because severe toxicity. Other systemic side effects in the remaining patients were acceptable. Seventeen patients received maintenance treatment. The median follow-up of all the patients included was 21 months. The 1, 2 and 3 years survivals were 64%, 33% and 22% respectively. This multicentric trial confirms the efficacity of subcutaneously-administered interleukin-2 in patients with metastatic renal cell carcinoma in terms of both response rate and survival. Unfortunately, increasing total doses of administrated interleukin-2 does not seem to increase efficacity according to response rate, but is more toxic.
OBJECTIVE: To try to define when and what type of operation should be performed in von Hippel-Lindau disease (VHL) with renal involvement. MATERIAL AND METHODS: Between 1985 and July 1996, 43 patients with renal involvement of VHL disease were followed in our department. We decided to operate on patients with one or several solid or complex tumours greater than 2.5 cm in diameter, by means of conservative surgery (tumour excision removing a layer of healthy parenchyma) when the kidney did not contain more than 5 or 6 tumours or radical nephrectomy in the other cases. Subsequent follow-up consisted of CT, chest x-ray and renal function tests every 6 months. RESULTS: Twenty-nine patients with a mean age of 33.6 years were operated. 21 patients (29 kidneys) were treated by conservative surgery: in situ in 20 cases and ex vivo in 9 cases; 3 cases were treated by bilateral radical nephrectomy, 4 by unilateral radical nephrectomy and 1 by resection of the prominent dome for urinary tract obstruction. Four cases of acute arterial thrombosis were observed following ex vivo surgery, requiring nephrectomy in every case. No serious complications were observed with in situ conservative surgery. A new lesion in the renal parenchyma remaining after conservative surgery was observed in 5 cases during follow-up (mean: 29 months). No local recurrence was observed after radical nephrectomy. Two nonoperated patients developed metastatic disease. CONCLUSION: Conservative treatment is usually possible: either simple surveillance, in the absence of any solid or complex tumours larger than 2.5 cm in diameter, or conservative surgery for tumours larger than 2.5 cm in diameter, with no more than 6 tumours per kidney; this attitude requires six-monthly follow-up by CT of the renal parenchyma.
BACKGROUND: Hormonotherapy temporarily controls symptoms in 80% of patients with metastatic prostate carcinoma. Once progression occurs, no consensus exists on further therapy. Oral etoposide (VP-16) has shown clinical efficacy in advanced small cell lung carcinoma, breast cancer, germ cell tumors, and lymphomas, A synergistic effect between etoposide and alkylating agents such as estramustine was recently reported. We began a prospective Phase II study of an oral combination of cyclophosphamide (CPM) and VP-16 in patients with hormone-refractory [correction of refactory] prostate carcinoma (HRPC). METHODS: Patients were orally treated with CPM (100 mg/day) and VP-16 (50 mg/day) for 14 days every 28 days. Therapy continued until there was evidence of disease progression. RESULTS: From November, 1992, to February, 1995, 20 patients with HRPC were entered into the study. Patients were eligible if they had an ECOG performance status (PS) of 0 to 2. All of the patients presented with bone metastasis, and 70% presented with bone pain. Seventy-five percent had failed at least two hormonal manipulations. The mean duration of treatment was 5 months (range 2-12). Performance status improved in 26% of the patients, and bone pain was relieved in 71%. An objective response was defined as a decrease of 50% or more in the prostate-specific antigen (PSA) level. One patient demonstrated a complete response, and six patients had partial responses assessed by PSA plasma levels (objective response rate: 35%). The mean duration of response was 8 +/- 6 months (range: 2-24). Median survival was 11 months. Toxicities were minimal. CONCLUSIONS: The combination of oral CPM and VP-16 may be an active and well tolerated regimen for patients with HRPC.