Pathological and clinical characterization of the 'troubled transplant': data from the DeKAF study

We are studying two cohorts of kidney transplant recipients, with the goal of defining specific clinicopathologic entities that cause late graft dysfunction: (1) prevalent patients with new onset late graft dysfunction (cross-sectional cohort); and (2) newly transplanted patients (prospective cohort). For the cross-sectional cohort (n = 440), mean time from transplant to biopsy was 7.5 +/- 6.1 years. Local pathology diagnoses included CAN (48%), CNI toxicity (30%), and perhaps surprisingly, acute rejection (cellular- or Ab-mediated) (23%). Actuarial rate of death-censored graft loss at 1 year postbiopsy was 17.7%; at 2 years, 29.8%. There was no difference in postbiopsy graft survival for recipients with versus without CAN (p = 0.9). Prospective cohort patients (n = 2427) developing graft dysfunction >3 months posttransplant undergo 'index' biopsy. The rate of index biopsy was 8.8% between 3 and 12 months, and 18.2% by 2 years. Mean time from transplant to index biopsy was 1.0 +/- 0.6 years. Local pathology diagnoses included CAN (27%), and acute rejection (39%). Intervention to halt late graft deterioration cannot be developed in the absence of meaningful diagnostic entities. We found CAN in late posttransplant biopsies to be of no prognostic value. The DeKAF study will provide broadly applicable diagnostic information to serve as the basis for future trials.

Histopathologic clusters differentiate subgroups within the nonspecific diagnoses of CAN or CR: preliminary data from the DeKAF study

The nonspecific diagnoses 'chronic rejection''CAN', or 'IF/TA' suggest neither identifiable pathophysiologic mechanisms nor possible treatments. As a first step to developing a more useful taxonomy for causes of new-onset late kidney allograft dysfunction, we used cluster analysis of individual Banff score components to define subgroups. In this multicenter study, eligibility included being transplanted prior to October 1, 2005, having a 'baseline' serum creatinine < or =2.0 mg/dL before January 1, 2006, and subsequently developing deterioration of graft function leading to a biopsy. Mean time from transplant to biopsy was 7.5 +/- 6.1 years. Of the 265 biopsies (all with blinded central pathology interpretation), 240 grouped into six large (n > 13) clusters. There were no major differences between clusters in recipient demographics. The actuarial postbiopsy graft survival varied by cluster (p = 0.002). CAN and CNI toxicity were common diagnoses in each cluster (and did not differentiate clusters). Similarly, C4d and presence of donor specific antibody were frequently observed across clusters. We conclude that for recipients with new-onset late graft dysfunction, cluster analysis of Banff scores distinguishes meaningful subgroups with differing outcomes.

Phase 1 dose-escalation study of CP-690 550 in stable renal allograft recipients: preliminary findings of safety, tolerability, effects on lymphocyte subsets and pharmacokinetics

CP-690 550 inhibits Janus kinase 3 with nanomolar potency. In this dose-escalation study, we assessed the safety, tolerability, effects on lymphocyte subsets, and pharmacokinetics of CP-690 550 when coadministered with mycophenolate mofetil in stable renal allograft recipients for 28 days. Twenty-eight patients were enrolled. Six patients received CP-690 550 5 mg twice daily (BID), 6 patients received 15 mg BID, 10 patients received 30 mg BID, and 6 patients received placebo. The most frequent adverse events were infections and gastrointestinal (abdominal pain, diarrhea, dyspepsia, and vomiting). CP-690 550 15 mg BID and 30 mg BID were associated with a mean decrease in hemoglobin from baseline of 11% and a mean decrease in absolute natural killer cell counts of 50%. CP-690 550 30 mg BID was also associated with a mean increase in absolute CD19(+) B-lymphocytes of 130%. There were no changes in the number of neutrophils, total lymphocytes, platelets, or CD4(+) or CD8(+) T cells; clinical chemistry; vital signs; or electrocardiograms from the pretreatment baseline. Administration of CP-690 550 without a concomitant calcineurin inhibitor resulted in CP-690 550 exposures consistent with previous studies in nontransplant subjects. Additional dose-ranging studies are warranted to evaluate the safety and efficacy of CP-690 550 in renal transplant recipients over longer treatment duration.

Role of beta3 integrin in acute renal allograft rejection in humans

BACKGROUND AND OBJECTIVES

Beta3 Integrin may play a role in the process of acute rejection by increasing leukocyte adhesion to the endothelium, cytotoxic T lymphocyte activation, and platelet aggregation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

For investigation of the role of beta3 integrin in the pathogenesis of acute rejection, this study examined the surface expression of beta3 integrin on leukocyte subsets and analyzed a common single-nucleotide polymorphism in exon 2 of the gene encoding the beta3 subunit that generates two beta3 integrin isoforms, termed Pl(A1) and Pl(A2). Pl(A) genotype was determined in blood samples from 445 renal allograft recipients at two centers. Patients were then grouped by Pl(A) genotype, and clinical outcomes as recorded in a preexisting database were analyzed.

RESULTS

Although almost all monocytes express beta3 integrin, its expression was also found on all leukocyte subsets, including T, B, and NK cells. The percentage of patients who experienced acute rejection was noted to be significantly higher in those with Pl(A1)/Pl(A1) (TT) genotype versus patients with the Pl(A1)/Pl(A2) or Pl(A2)/Pl(A2) (CT or CC) genotypes (33% for TT versus 20% for CT or CC). In a multivariate analysis, the Pl(A1)/Pl(A1) (TT) genotype remained significantly associated with acute rejection. Patients with Pl(A1)/Pl(A1) (TT) genotype also exhibited a higher number of acute rejection episodes per patient.

CONCLUSIONS

The Pl(A1)/Pl(A1) (TT) genotype is associated with an increased incidence of acute renal allograft rejection in humans, supporting a role for beta3 integrin in the pathophysiology of acute rejection.

Positive margins in laparoscopic partial nephrectomy in 855 cases: a multi-institutional survey from the United States and Europe

PURPOSE

Open partial nephrectomy has emerged as the standard of care in the management of renal tumors smaller than 4 cm. While laparoscopic radical nephrectomy has been shown to be comparable to open radical nephrectomy with respect to long-term outcomes, important questions remain unanswered regarding the oncological efficacy of laparoscopic partial nephrectomy. We examined the practice patterns and pathological outcomes following laparoscopic partial nephrectomy.

MATERIALS AND METHODS

A survey was sent to academic medical centers in the United States and in Europe performing laparoscopic partial nephrectomy. The total number of laparoscopic partial nephrectomies, positive margins, indications for intraoperative frozen biopsy as well as tumor size and position were queried.

RESULTS

Surveys suitable for analysis were received from 17 centers with a total of 855 laparoscopic partial nephrectomy cases. Mean tumor size was 2.7 cm (+/-0.6). There were 21 cases with positive margins on final pathology, giving an overall positive margin rate of 2.4%. Intraoperative frozen sections were performed selectively at 10 centers based on clinical suspicion of positive margins on excised tumor. Random biopsies were routinely performed on the resection bed at 5 centers. Frozen sections were never performed at 2 centers. Of the 21 cases with positive margins 14 underwent immediate radical nephrectomy based on the frozen section and 7 were followed expectantly.

CONCLUSIONS

Early experience with laparoscopic partial nephrectomy in this multicenter study demonstrates oncological efficacy comparable to that of open partial nephrectomy with respect to the incidence of positive margins. The practice of intraoperative frozen sections varied among centers and is not definitive in guiding the optimal surgical treatment.

Dietary essential fatty acids and gender-specific behavioral responses in cranially irradiated rats

Specific memory deficits, reduced intellectual processing speed, and a variety of social and behavioral problems have been implicated as long-term effects of cranial radiation therapy (CRT). These deficits are thought to be related to changes in brain cytology and structure associated with microvascular aberrations. N-3 fatty acids may serve as protectants in pediatric patients who receive CRT for brain tumors. Timed-pregnant rat dams were fed one of four diets that were identical in all respects, except for their essential fatty acid content. The dams were placed on these diets at the beginning of the third trimester of gestation and their pups remained on them throughout the study. The rats' behavioral response as judged by acoustic startle response (ASR) and neurocognitive response (performance in a radial maze, RM) were evaluated in relation to diet, gender, and CRT. The following hypotheses were tested: (1) female rats will show greater CRT-induced neurocognitive and behavioral deficits; (2) dietary n-3 fatty acids will diminish CRT-induced neurocognitive and behavioral deficits; (3) gender-specific differences would be dampened by n-3 fatty acids in the diet. All three hypotheses were partially supported. These findings are discussed in light of the potential neuroprotective effects of n-3 fatty acids.

Nerve Sparing Laparoscopic Radical Prostatectomy: Our Technique

PURPOSE

To describe our technique of nerve sparing laparoscopic radical prostatectomy (LRP). We present the oncological and functional results (potency and urinary continence).

MATERIAL AND METHODS

LRP has become standard at our institution based on experience with more than 2800 consecutive cases operated on between 1997 and 2005. From May 2003 to March 2005 a total of 677 LRP were performed, 425 consecutive patients candidates for a nerve sparing technique have been operated using the intrafascial approach. The challenge of our technique is to remove the prostate without any thermic and mechanic traumatism, avoiding dissection of outer layer. Oncological data were assessed by pathological examination and post-operative PSA level. Functional results were assessed with a self questionnaire.

RESULTS

By pathological stage, 2 pT2a specimens (7.4%), 7 pT2b specimens (21%), 44 pT2c specimens (24%), 63 pT3a specimens (43%), 11 pT3b specimens (46%) were found to have positive surgical margins (SMs). In 86 specimen (59%) positive SMs were focal inframillimetric. Median follow-up was 11 months (range 1-22). The continence rate (no leakage/no pad) was 95% at 6 months, confirmed at 12 months among 202 patients. For 137 patients, potency rate was 58.5% at 12 months.

CONCLUSION

Intrafascial LRP provides satisfactory results in regard to recovery of continence and sexual function. Long-term progression and survival outcome are necessary before this procedure should be offered as a replacement for interfascial nerve sparing technique.

[Laparoscopic promontofixation technique]

Laparoscopic promontofixation often remains possible whatever the previous history of pelvic surgery, including the placing of prosthetic material. Preoperative care is standardized and is accompanied by antibiotic prophylaxis, preventive antithrombotic treatment and in the event of a history of pelvic surgery, a digestive preparation. Positioning of the patient must plan a 30 degrees Trendelenbourg position. After the introduction of trocars, initial surgery comprises interrectovaginal dissection to free the whole posterior surface of the vagina. This is followed by the installation of a posterior mesh pre-cut in an arch. The anterior face of the promontory is then freed after incision of the posterior peritoneum with the patient placed beforehand in a Trendelenbourg position. After intervesical vaginal dissection, the anterior prosthesis comprising a precut polyester mesh is fixed avoiding excess traction. The end of the surgery involves careful reperitonization of all the prosthetic parts. Possible specific surgical complications are vascular and visceral wounds. Postoperative secondary haemorrhage and gastrointestinal occlusion may occur. Occurrence of an inflammatory syndrome and low back pain suggests spondylodicitis and MRI should be performed. Vaginal erosion on the prosthesis (1.6 to 10% depending on the series) may occur after several months and seems relatively independent of the prosthetic material used.

Subcutaneous interleukin-2, interferon alpha-2b and 5-fluorouracil in metastatic renal cell carcinoma as second-line treatment after failure of previous immunotherapy: a phase II trial

The association of interleukin-2 (IL-2), interferon alpha-2a (IFNalpha), 5-fluorouracil (5-FU) has been reported to induce response in metastatic renal cell carcinoma (MRCC). This study evaluated IL-2, IFNalpha and 5FU as second-line treatment after failure under immunotherapy. A total of 35 patients received IL-2, at 9 x 10(6) IU m(-2), once or t.i.d, 5 days a week, every other week. Interferon alpha was administered at 6 MUI, TIW along with IL-2 every week. 5-Fluorouracil was given at 750 mg m(-2) day(-1) on days 1-5 every 4 weeks. One cycle lasted 8 weeks. All patients were evaluable for response and toxicity. There were two objective responses (5.7%) and 14 stable diseases (40%). Survival was 14 months. In all, 17 patients experienced grade 3 toxicity. The predictive factor for progression to second-line immunotherapy was the results of first-line immunotherapy, and performance status, delay from primary tumour to metastases and response or stabilisation to chemo-immunotherapy for survival. IL-2, IFNalpha and 5-FU induce low objective response but stabilisation in patients with MRCC having failed with immunotherapy, and may be considered only in selected patients on performance status, stabilisation or response after first-line immunotherapy and interval from their primary tumour to metastases.

Equivalent pharmacokinetics of mycophenolate mofetil in African-American and Caucasian male and female stable renal allograft recipients

African-American (AA) renal transplant recipients require higher doses of mycophenolate mofetil (MMF) than Caucasians. A hypothesized pharmacokinetic (PK) difference was tested in stable renal transplant recipients. Whole blood was collected before, and 20, 40 and 75 min, and 2, 3, 4, 6, 8 and 12 h after the MMF dose. Mycophenolic acid (MPA) and its glucuronide metabolite (MPAG) were analyzed using HPLC. Analysis of variance was performed for the primary end-points of dose-adjusted PK parameters AUC0-12 and Cmax of MPA using log-transformed values. Differences between races and genders were estimated: 90% confidence intervals (CI) were calculated. Back-transformation gave estimates of the race and gender ratio and their CI. Equivalence of the groups was determined if the 90% confidence limits were included in the interval (0.80, 1.25). The calculated PK parameters were comparable among the four subgroups (Caucasian, AA, Male, Female). The 90% CIs for the ratio of dose-adjusted AUC0-12 of MPA between races were between 89.7 and 112.9%. There were no race, gender or race-by-gender effects (p-values = 0.196) nor differences between diabetics and nondiabetics. This study demonstrates that dosing requirement for MMF in AA and Caucasians is unlikely to be related to different exposures to MPA.

Evolution of immunosuppression and continued importance of acute rejection in renal transplantation

As steady improvement in short-term kidney graft survival and long-term outcomes prolongs the lives of transplant patients, responsibility for their care is shifting away from transplant specialists and into the hands of community nephrologists. Therefore, community nephrologists need to have a deeper understanding of immunosuppressive therapies than ever before. Pharmacologic immunosuppression has been continuously evolving over the past two decades. Azathioprine was introduced in the early 1960s. Introduction of cyclosporine (CsA) in 1983 revolutionized short-term outcomes after renal transplantation. The first monoclonal antibody immunosuppressant, OKT3, was introduced in 1986. The 1990s saw the introduction of a number of important new agents, including mycophenolate mofetil (MMF), tacrolimus, and a microemulsion CsA, as well as two new monoclonal antibodies. Combinations of these new agents, along with improving clinical care, have produced 1-year patient survival approaching 100% and graft survival exceeding 90%. The newest class of agents, the first of which is sirolimus, is called target of rapamycin (TOR) inhibitors and is used with CsA for maintenance therapy. Immunosuppressive drug therapy after kidney transplantation continues to evolve. There is a variety of pharmacologic combinations from which to choose, based on immunologic risk and side effect profiles. As new regimens are developed, ongoing communications between the transplant center and community nephrologists will be required to implement therapeutic changes and optimize patient care successfully.

Proposal for a "European Scoring System for Laparoscopic Operations in Urology"

PURPOSE

To propose a scoring system of difficulties for the most currently performed laparoscopic procedures in urology.

MATERIALS AND METHODS

Each current laparoscopic procedure has been evaluated according to three different criteria: technical difficulty, operative risk and the attention required. Each criterion is scored from 1 (minimal impact of the criteria) to 7 (maximal impact of the criteria). The sum of the 3 criteria is used to classify each operation according to an increasing level of global difficulty, classified into 6 levels: easy (E: sum of criteria between 3 and 5), slightly difficult (SD: sum of criteria between 6 and 8), fairly difficult (FD: sum of criteria between 9 and 11), difficult (D: sum of criteria between 12 and 14), very difficult (VD: sum of criteria between 15 and 17), extremely difficult (ED: sum of criteria greater than 18).

RESULTS

Procedures currently performed by laparoscopy have been selected for evaluation according to the above criteria, and retrospectively validated by European experts in laparoscopic urology according to their experience and the international literature.

CONCLUSION

This proposal of a scoring scale system is a basis for discussion, teaching and learning of urological laparoscopy. By necessity, this scale is evolving and will be regularly reconsidered and updated every 5 years.

In vitro immunization of patient T cells with autologous bone marrow antigen presenting cells pulsed with tumor lysates

Presentation of cell-associated antigen to T cells is a critical event in the initiation of an anti-tumor immune response but it appears to often be deficient or limiting. Here we report an experimental system for stimulation of human T lymphocytes using autologous antigen presenting cells (APCs) and autologous tumor cells. Two types of APCs were prepared from human bone marrow: MC and DC. MC were produced by using GM-CSF and SCF. DC were obtained with the same cytokines plus IL-4. DC and MC were generated in parallel from the same patients and their phenotypes and capacities to prime T lymphocytes were analyzed and compared. MC were CD14+, CD1a-, CD33+ and HLA-DR+. Two populations of DC were defined: immature DC were uniformly CD1a-; mature DC expressed CD1a, CD80, CD86, HLA-DR, CD54 and CD58 but lacked surface CD14. Stimulation of autologous T lymphocytes was studied by measuring their proliferation and cytotoxic function. In more than 80% of our experiments the proliferation of autologous T lymphocytes cocultured with APC pulsed or not with tumor cell lysates was higher than that of T cells cultured alone. DC were more effective than MC in stimulating proliferation of lymphocytes. The capacity of a patient's autologous bone marrow-derived APC to stimulate T cells when exposed to autologous tumor cell lysates suggest that such antigen-exposed APC may be useful in specific anti-tumor immunotherapy protocols.