Thomas Schwaab

RENAL nephrometry score predicts surgical outcomes of laparoscopic partial nephrectomy

Study Type – Therapy (case series)

Dendritic Cell Infiltration in Colon Cancer

We quantitatively evaluated dendritic cell (DC) infiltration in primary colorectal cancers from 44 patients and metastatic colorectal tumors from 13 patients using immunohistochemistry for the DC marker CD83, HLA-DR, and the DC activation molecules CD40 and CD86. Nearly all CD83+ cells were also HLA-DR+, CD40+, and CD86+, indicating that the DCs that infiltrate colon cancer in vivo express the activation and costimulatory molecules associated with a mature DC phenotype. The density of DCs in colorectal cancer primaries was three times lower than that seen in normal colonic mucosa (0.29 versus 0.84 CD83+ cells/ high-power field (hpf), p < 0.001). Dendritic cells were rarely observed in metastatic tumors: DC density in metastases was sixfold lower than in colorectal primary tumors (0.05 versus 0.29 CD83+ cells/hpf, p < 0.001). Because cytokines have been shown, in vitro, to exert potent effects on DCs, we also evaluated the relationship between intratumor DC density and the expression of cytokines by tumor-infiltrating lymphocytes (TILs) and tumor cells. Expression of interleukin-10 and transforming growth factor &bgr; by either TIL or tumor cells was not associated with decreased DC density or decreased expression of CD40 or CD86 on DCs. Tumor expression of vascular endothelial growth factor was associated with a more than twofold increase in DC density (p = 0.01). Patients who had a high proportion of TILs expressing tumor necrosis factor (TNF) had a greater intratumor mature DC density than patients with a low proportion of TNF + TIL (0.54 versus 0.21 CD83+ cells/hpf, p < 0.01).

Clinical and immunologic effects of intranodal autologous tumor lysate-dendritic cell vaccine with aldesleukin (interleukin 2) and IFN-α2a therapy in metastatic renal cell carcinoma patients

Purpose: To evaluate the clinical and immunologic outcomes of DC (dendritic cell) vaccine with interleukin (IL)-2 and IFN-α 2a in metastatic renal cell carcinoma patients. Experimental Design: Eighteen consented and eligible patients were treated. Peripheral blood monocytes were cultured ex vivo into mature DCs and loaded with autologous tumor lysate. Treatment consisted of five cycles of intranodal vaccination of DCs (1 × 107 cells/1 mL Lactated Ringers solution), 5-day continuous i.v. infusion of IL-2 (18MiU/m2), and three s.c. injections of IFN-α 2a (6MiU) every other day. Response Evaluation Criteria in Solid Tumors criteria were used for disease assessment. Correlative immunologic end points included peripheral blood lymphocyte cell phenotype and function as well as peripheral blood anti–renal cell carcinoma antibody and cytokine levels. Results: All patients received between two and five treatment cycles. Toxicities consisted of known and expected cytokine side effects. Overall objective clinical response rate was 50% with three complete responses. Median time to progression for all patients was 8 months, and median survival has not been reached (median follow up of 37+ months). Treatment-related changes in correlative immunologic end points were noted and the level of circulating CD4+ T regulatory cells had a strong association with outcome. Pre–IP-10 serum levels approached significance for predicting outcome. Conclusions: The clinical and immunologic responses observed in this trial suggest an interaction between DC vaccination and cytokine therapy. Our data support the hypothesis that modulation of inflammatory, regulatory, and angiogenic pathways are necessary to optimize therapeutic benefit in renal cell carcinoma patients. Further exploration of this approach is warranted.

IN VIVO DESCRIPTION OF DENDRITIC CELLS IN HUMAN RENAL CELL CARCINOMA

PURPOSE Dendritic cells (DCs) are efficient and effective antigen-presenting cells that play a major role in initiating the primary immune response. They are the most potent stimulators of T-cell activation and would thus be expected to be of great importance in the antitumoral immune response. Although DC phenotype and function have been described under in vitro conditions, their in vivo characteristics are less well detailed. Human renal cell carcinoma (RCC) is an excellent model to explore tumor infiltrating dendritic cells (TiDCs) because of rare clinical spontaneous regressions and the association of high numbers of tumor infiltrating lymphocytes (TiLs), suggesting a strong immune response. MATERIALS AND METHODS We determined the in situ phenotype of mature CD83+ TiDCs using monoclonal antibodies to known activation molecules (CD86 [B7.2], CD80 [B7.1], CD40, CD54, CD1a and HLA-DR). Seventeen primary RCCs, representing four distinct histologies, were evaluated using double-staining immunohistochemical techniques and light microscopy. RESULTS CD83+ TiDCs were found in all tumors. Expression of CD40 correlated with expression of CD1a on CD83+ TiDCs. Expression of CD54 (ICAM-1) correlated with a lower expression of CD86 (B7.2) as well as a decrease in CD3+ and CD8+ TiLs. CONCLUSIONS These data suggest a de novo lipid or sugar-based immunogenic antigen presentation by TiDCs. Also, the data support an impaired antigen-presenting capability for CD54+ TiDCs based on the decreased coexpression of CD86 (B7.2) and the decrease of associated CD8+ TiLs.

A RANDOMIZED PHASE II TRIAL COMPARING TWO DIFFERENT SEQUENCE COMBINATIONS OF AUTOLOGOUS VACCINE AND HUMAN RECOMBINANT INTERFERON γ AND HUMAN RECOMBINANT INTERFERON α2B THERAPY IN PATIENTS WITH METASTATIC RENAL CELL CARCINOMA: CLINICAL OUTCOME AND ANALYSIS OF IMMUNOLOGICAL PARAMETERS

PURPOSE The clinical observation of spontaneous regression in patients with renal cell carcinoma (RCC) and the response to various immunotherapeutic therapies strongly suggest a role for the host immune system in this disease. Prior studies showed that sequential administration of interferon (IFN) gamma and IFN alpha to RCC patients was safe. Clinical responses as well as immune changes in the peripheral blood mononuclear cell compartment were observed. Autologous tumor cell vaccines (AV) have also demonstrated activity in renal cell carcinoma. We hypothesize that the addition of AV to sequential IFN gamma and a therapy might improve the tumor-specific immune response by providing an appropriate source of antigen in the appropriate cytokine environment. To our knowledge, this is the first trial using AV combined with IFN alpha and IFN gamma. The purpose of this study was to evaluate the feasibility of manufacturing and administering (AV) from resected tumor samples, and administration of AV with combination IFN gamma and IFN alpha therapy. Finally, the impact on immunological parameters of these treatment options was assessed. MATERIALS AND METHODS Patients with metastatic RCC were randomly assigned to receive AV plus bCG along with a sequential administration of IFN gamma and a either together or after initiation of vaccine. Toxicity and clinical responses were evaluated. Modulations of the immune system were investigated by analyzing phenotype, cytokine mRNA expression, T cell proliferation and cytotoxicity in the peripheral blood mononuclear cell compartment. RESULTS Fourteen patients with metastatic renal cell carcinoma were enrolled in this study; 9 were available for response evaluation. In a 70 day period, 3 (33%) showed mixed responses, 5 (56%) stable disease and 1 (11%) progression of disease. Toxicities were consistent with previous clinical reports. In the flow-cytometry phenotype analysis, stimulation of distinct subsets of circulating T-lymphocytes and a decrease of CD8+ T cell subsets was demonstrated. T-cell proliferation to allogeneic tumor cell stimulation improved following treatment. IL-4 and IL-5 mRNA levels were reduced in all patients after treatment. Patients who responded to treatment did not produce any IL-4 mRNA at all, before or after treatment. CONCLUSIONS AV with IFNgamma and IFNalpha therapy might induce a MHC class-mediated cytotoxic T lymphocyte (CTL) response. We suggest that adequate therapy might direct T cell response toward a Th1 type response. We hypothesize a state of improved immune readiness in patients who might eventually respond to immunotherapy.

Phase I pilot trial of the bispecific antibody MDXH210 (anti-FcγRI X anti-HER-2/neu) in Patients whose prostate cancer overexpresses HER-2/neu

The goal of this study was to evaluate, in patients with prostate cancer, the toxicity profile and biologic activity of the bispecific antibody MDXH210, which has specificity for the non–ligand-binding site of the high-affinity immunoglobulin G receptor (Fc&ggr;RI) and the extracellular domain of the HER-2/neu proto-oncogene product. Patients with prostate cancer that expressed HER-2/neu were entered into a phase I dose-escalation trial of MDXH210. Patients received an intravenous infusion MDXH210 during a period of 2 h three times per week for 2 weeks and were monitored for toxicity. Pharmacokinetic and pharmacodynamic parameters were measured and included the biologic end points of monocyte-bound MDXH210, cytokine production, and clinical response. Seven patients were treated with MDXH210 doses ranging from 1 to 8 mg/m2. In general, MDXH210 was well tolerated, with only mild infusion-related malaise, fever, chills, and myalgias. No dose-limiting toxic effects were observed. Biologic effects included induction of low plasma concentrations of tumor necrosis factor-&agr; and interleukin-6 observed immediately after MDXH210 infusion and 70% saturation of circulating monocyte-associated Fc&ggr;RI with MDXH210 at a dose level of 4 to 8 mg/m2. Five of six patients had stable prostate-specific antigen levels during the course of 40 days or more. Circulating plasma HER-2/neu levels decreased by 80% at days 12 and 29 (p = 0.03 and 0.06, respectively, by the Wilcoxon signed rank test). MDXH210 can be given safely to patients with HER-2/neu–positive prostate cancer in doses of at least 8 mg/m2. At the doses studied, biologic activity was demonstrated and characterized by binding of MDXH210 to circulating monocytes, release of monocyte-derived cytokines, a decrease in circulating HER-2/neu, and short-term stabilization of prostate-specific antigen levels.

Renal Cell Carcinoma in Octogenarians: Nephron Sparing Surgery Should Remain the Standard of Care

PURPOSE Data regarding clinical outcomes in elderly patients with renal cell carcinoma are scarce. We determined management, and overall and cancer specific survival in elderly patients with renal cell carcinoma. MATERIALS AND METHODS Using the Surveillance, Epidemiology, and End Results database we identified 59,944 patients who underwent partial or radical nephrectomy for renal cell carcinoma between 1988 and 2005. Patients were separated into 2 groups of those younger than 80 years, and those 80 years old or older, and were stratified by clinical variables. Chi-square, multivariate logistic regression and Kaplan-Meier analyses were used to determine differences between the cohorts in terms of surgical approach, and overall and cancer specific survival. RESULTS In total, 4,227 patients (7.5%) were older than 80 years old. Younger patients more likely underwent partial nephrectomy than their older counterparts (13% vs 8%, p <0.001). At a median followup of 37 months (range 0 to 215) for patients younger than 80 years, and 27 months (range 0 to 203) for octogenarians, older patients were 2.32 times more likely to die (95% CI 2.22-2.42, p <0.001) and 1.33 times more likely to die of renal cell carcinoma (95% CI 1.23-1.43, p <0.001) than their younger counterparts. Older patients who underwent radical nephrectomy were 2.54 times more likely to die of renal cell carcinoma (95% CI 1.68-3.84, p <0.001) than older patients who underwent partial nephrectomy. CONCLUSIONS Older patients are less likely to undergo partial nephrectomy than their younger counterparts. Octogenarians treated with partial nephrectomy are less likely to die of renal cell carcinoma than those who undergo radical nephrectomy.

Learning curves for robot-assisted and laparoscopic partial nephrectomy.

OBJECTIVES To evaluate the learning curve of robot-assisted partial nephrectomy (RAPN) and laparoscopic partial nephrectomy (LPN) between two surgeons at a single institution. METHODS A prospectively maintained, Institutional Review Board (IRB)-approved kidney surgery database was reviewed retrospectively and the first 116 consecutive LPNs performed by one surgeon (Hyung Kim) and 116 consecutive RPNs performed by a second surgeon (Thomas Schwaab) were identified. The learning curve was evaluated by examining the operative times, warm ischemia times (WITs), estimated blood loss, the postoperative estimated glomerular filtration rate (eGFR), and intra- and postoperative complications in the quartiles of 29 patients. The LPNs performed by Hyung Kim were done following completion of a minimally invasive fellowship. Thomas Schwaab had minimal experience with LPN and no fellowship training before starting RAPN. RESULTS The RAPN and LPN groups had similar patient and tumor characteristics. The RAPN group had a higher preoperative eGFR (74.1±22.04 vs. 80.95±21.25 mL/minutes, p=0.015) and a worse Eastern Cooperative Oncology Group (ECOG) performance status (ECOG 1+ in 12% vs. 2.6%, p<0.001) compared with the LPN group. Rates of intraoperative (p=0.203) and postoperative (p=0.193) complications were similar. In the RAPN group, operating room (OR) time (161±51 vs. 203±55 minutes, p<0.001) and WIT (17.7±14.8 vs. 21.8±9.1 minutes, p<0.001) were shorter. Postoperative stay was longer in the RAPN group (2.4±2.2 vs. 1.67±1.1 days, p<0.001). The percentage decrease in postoperative eGFR was lower in the RAPN group versus the LPN (9.6% vs. 10%). The learning curves differed for log tumor size, log WIT, and postoperative complications. CONCLUSIONS The variables of the learning curve for RAPN can be obtained earlier than the same variables for LPN. RAPN had a shorter OR time and WITs. The shorter WITs, earlier in the series, led to consistently lower fluctuations in GFR and preservation of the renal function. The learning curves for each procedure need to be re-evaluated at longer intervals to ensure their accuracy.

Regulatory T-Cells and Associated Pathways in Metastatic Renal Cell Carcinoma (mRCC) Patients Undergoing DC-Vaccination and Cytokine-Therapy

Purpose To evaluate CD4+CD25+FOXP3+ T regulatory cells (TREG) and associated immune-regulatory pathways in peripheral blood lymphocytes (PBL) of metastatic renal cell carcinoma (mRCC) patients and healthy volunteers. We subsequently investigated the effects of immunotherapy on circulating TREG combining an extensive phenotype examination, DNA methylation analysis and global transcriptome analysis. Design Eighteen patients with mRCC and twelve volunteers (controls) were available for analysis. TREG phenotype was examined using flow cytometry (FCM). TREG were also quantified by analyzing the epigenetic status of the FOXP3 locus using methylation specific PCR. As a third approach, RNA of the PBL was hybridized to Affymetrix GeneChip Human Gene 1.0 ST Arrays and the gene signatures were explored using pathway analysis. Results We observed higher numbers of TREG in pre-treatment PBL of mRCC patients compared to controls. A significant increase in TREG was detected in all mRCC patients after the two cycles of immunotherapy. The expansion of TREG was significantly higher in non-responders than in responding patients. Methylation specific PCR confirmed the FCM data and circumvented the variability and subjectivity of the FCM method. Gene Set Enrichment Analysis (GSEA) of the microarray data showed significant enrichment of FOXP3 target genes, CTLA-4 and TGF-ß associated pathways in the patient cohort. Conclusion Immune monitoring of the peripheral blood and tumor tissue is important for a wide range of diseases and treatment strategies. Adoption of methodology for quantifying TREG with the least variability and subjectivity will enhance the ability to compare and interpret findings across studies.

Gene expression profile of peripheral blood lymphocytes from renal cell carcinoma patients treated with IL-2, Interferon-α and dendritic cell vaccine

Lymphocytes are a key component of the immune system and their differentiation and function are directly influenced by cancer. We examined peripheral blood lymphocyte (PBL) gene expression as a biomarker of illness and treatment effect using the Affymetrix Human Gene ST1 platform in patients with metastatic renal cell carcinoma (mRCC) who received combined treatment with IL-2, interferon-?-2a and dendritic cell vaccine. We examined gene expression, cytokine levels in patient serum and lymphocyte subsets as determined by flow cytometry (FCM). Pre-treatment PBLs from patients with mRCC exhibit a gene expression profile and serum cytokine profile consistent with inflammation and proliferation not found in healthy donors (HD). PBL gene expression from patients with mRCC showed increased mRNA of genes involved with T-cell and TREG-cell activation pathways, which was also reflected in lymphocyte subset distribution. Overall, PBL gene expression post-treatment (POST) was not significantly different than pre-treatment (PRE). Nevertheless, treatment related changes in gene expression (post-treatment minus pre-treatment) revealed an increased expression of T-cell and B-cell receptor signaling pathways in responding (R) patients compared to non-responding (NR) patients. In addition, we observed down-regulation of TREG-cell pathways post-treatment in R vs. NR patients. While exploratory in nature, this study supports the hypothesis that enhanced inflammatory cytotoxic pathways coupled with blunting of the regulatory pathways is necessary for effective anti-cancer activity associated with immune therapy. This type of analysis can potentially identify additional immune therapeutic targets in patients with mRCC.