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Richard I Fisher

Publications and source records attributed to Richard I Fisher.

At least 19 recordsLinked to original sources
PubMed2006

B cell reconstitution after rituximab treatment of lymphoma recapitulates B cell ontogeny.

The long-term immunologic effects of B cell depletion with rituximab and the characteristics of the reconstituting B cell pool in lymphoma patients are not well defined, despite the widespread usage of this therapy. Here we report that during the B cell reconstitution phase a majority of the peripheral blood B cells have an immature transitional phenotype (47.8%+/-25.2% vs. 4.4%+/-2.4% for normal controls, p<0.0001), similar to what has been described during the original ontogeny of the immune system and following bone marrow transplantation. Moreover, the recovery of the CD27+ memory B cell pool was delayed compared to normal B cell ontogeny, remaining below normal controls at 1 year post-rituximab (4.4%+/-3% vs. 31%+/-7%, p<0.0001). Expansion of functionally immature B cells and decreased memory B cells may contribute to an immunodeficient state in patients recovering from rituximab mediated B cell depletion, particularly with repeated treatment.

Adult↗
PubMed2006

Multicenter phase II study of bortezomib in patients with relapsed or refractory mantle cell lymphoma.

PURPOSE: Evaluate response rate, duration of response (DOR), time-to-progression (TTP), overall survival (OS), and safety of bortezomib treatment in patients with relapsed or refractory mantle cell lymphoma (MCL). PATIENTS AND METHODS: Bortezomib 1.3 mg/m(2) was administered on days 1, 4, 8, and 11 of a 21-day cycle, for up to 17 cycles. Response and progression were determined using International Workshop Response Criteria, both using data from independent radiology review and by the investigators. Primary efficacy analyses were based on data from independent radiology review. RESULTS: In total, 155 patients were treated. Median number of prior therapies was one (range, one to three). Response rate in 141 assessable patients was 33% including 8% complete response (CR)/unconfirmed CR. Median DOR was 9.2 months. Median TTP was 6.2 months. Results by investigator assessments were similar. Median OS has not been reached after a median follow-up of 13.4 months. The safety profile of bortezomib was similar to previous experience in relapsed multiple myeloma. The most common adverse events grade 3 or higher were peripheral neuropathy (13%), fatigue (12%), and thrombocytopenia (11%). Death from causes that were considered to be treatment related was reported for 3% of patients. CONCLUSION: These results confirm the activity of bortezomib in relapsed or refractory MCL, with predictable and manageable toxicities. Bortezomib provides significant clinical activity in terms of durable and complete responses, and may therefore represent a new treatment option for this population with usually very poor outcome. Studies of bortezomib-based combinations in MCL are ongoing.

Adult↗
PubMed2006

Phase II trial of CHOP chemotherapy followed by tositumomab/iodine I-131 tositumomab for previously untreated follicular non-Hodgkin's lymphoma: five-year follow-up of Southwest Oncology Group Protocol S9911.

PURPOSE: Advanced follicular lymphoma (FL) is incurable with conventional chemotherapy and radiotherapy, and optimal front-line management is controversial. This study was performed to determine the efficacy of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy followed by tositumomab/iodine I-131 tositumomab. PATIENTS AND METHODS: From 1999 to 2000, the Southwest Oncology Group (SWOG) conducted a phase II trial (S9911) to test a novel new regimen consisting of six cycles of CHOP chemotherapy followed 4 to 8 weeks later by tositumomab/iodine I-131 tositumomab in 90 eligible patients with previously untreated, advanced-stage FL. RESULTS: The overall response rate was 91%, including a 69% complete remission (CR) rate. After a median follow-up time of 5.1 years, the estimated 5-year overall survival (OS) rate was 87%, and the progression-free survival (PFS) rate was 67%. The 5-year estimates of OS and PFS were each 23% better (absolute difference) than the corresponding figures for patients treated on previous SWOG protocols with CHOP alone. An analysis according to the Follicular Lymphoma International Prognostic Index showed that 21% of patients had high-risk features, 44% had intermediate-risk features, and 34% had low-risk features. High-risk patients had worse OS than lower risk patients (P = .05), but differences in PFS were not statistically significant (P = .21). Serial monitoring of the t(14;18) translocation in bone marrow by polymerase chain reaction demonstrated that 32 of 38 informative patients obtained molecular CRs, including seven patients (18%) after CHOP and 24 additional patients (63%) after tositumomab/iodine I-131 tositumomab. (The timing of conversion of one patient was unclear.) CONCLUSION: A prospective, phase III, randomized Intergroup Trial is currently underway comparing the efficacy of the promising CHOP + tositumomab/iodine I-131 tositumomab regimen with the efficacy of CHOP + rituximab.

Adult↗
PubMed2006

Molecular diagnosis of Burkitt's lymphoma.

BACKGROUND: The distinction between Burkitt's lymphoma and diffuse large-B-cell lymphoma is crucial because these two types of lymphoma require different treatments. We examined whether gene-expression profiling could reliably distinguish Burkitt's lymphoma from diffuse large-B-cell lymphoma. METHODS: Tumor-biopsy specimens from 303 patients with aggressive lymphomas were profiled for gene expression and were also classified according to morphology, immunohistochemistry, and detection of the t(8;14) c-myc translocation. RESULTS: A classifier based on gene expression correctly identified all 25 pathologically verified cases of classic Burkitt's lymphoma. Burkitt's lymphoma was readily distinguished from diffuse large-B-cell lymphoma by the high level of expression of c-myc target genes, the expression of a subgroup of germinal-center B-cell genes, and the low level of expression of major-histocompatibility-complex class I genes and nuclear factor-kappaB target genes. Eight specimens with a pathological diagnosis of diffuse large-B-cell lymphoma had the typical gene-expression profile of Burkitt's lymphoma, suggesting they represent cases of Burkitt's lymphoma that are difficult to diagnose by current methods. Among 28 of the patients with a molecular diagnosis of Burkitt's lymphoma, the overall survival was superior among those who had received intensive chemotherapy regimens instead of lower-dose regimens. CONCLUSIONS: Gene-expression profiling is an accurate, quantitative method for distinguishing Burkitt's lymphoma from diffuse large-B-cell lymphoma.

Adolescent↗
PubMed2006

Rituximab-CHOP versus CHOP alone or with maintenance rituximab in older patients with diffuse large B-cell lymphoma.

PURPOSE: To address early and late treatment failures in older patients with diffuse large B-cell lymphoma (DLBCL), we designed a two-stage randomized trial of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) versus rituximab plus CHOP (R-CHOP), with a second random assignment to maintenance rituximab (MR) or observation in responding patients. PATIENTS AND METHODS: Untreated DLBCL patients who were 60 years or older were randomly assigned to R-CHOP (n = 318) or CHOP (n = 314); 415 responders were randomly assigned to MR (n = 207) or observation (n = 208). The primary end point was failure-free survival (FFS). All P values were two sided. RESULTS: Three-year FFS rate was 53% for R-CHOP patients and 46% for CHOP patients (P = .04) at a median follow-up time of 3.5 years. Two-year FFS rate from second random assignment was 76% for MR compared with 61% for observation (P = .009). No significant differences in survival were seen according to induction or maintenance therapy. FFS was prolonged with MR after CHOP (P = .0004) but not after R-CHOP (P = .81) with 2-year FFS rates from second random assignment of 77%, 79%, 74%, and 45% for R-CHOP, R-CHOP + MR, CHOP + MR, and CHOP, respectively. In a secondary analysis excluding MR patients, R-CHOP alone reduced the risks of treatment failure (P = .003) and death (P = .05) compared with CHOP alone. CONCLUSION: Rituximab administered as induction or maintenance with CHOP chemotherapy significantly prolonged FFS in older DLBCL patients. After R-CHOP, no benefit was provided by MR. These results, which are consistent with an additive effect of rituximab, suggest that future studies could focus on maintenance strategies with novel agents as well as new induction therapies.

Age Factors↗
PubMed2006

Prognostic significance of Bcl-6 protein expression in DLBCL treated with CHOP or R-CHOP: a prospective correlative study.

Bcl-6 protein expression, a marker of germinal center origin, has been associated with a favorable prognosis in diffuse large B-cell lymphoma (DLBCL). To determine the prognostic significance of this marker when rituximab (R) was added to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy, we prospectively studied Bcl-6 protein expression by immunohistochemical staining of 199 paraffin-embedded specimens from patients enrolled in the US Intergroup phase 3 trial comparing R-CHOP to CHOP with or without maintenance R. In Bcl-6(-) patients, failure-free survival (FFS) and overall survival (OS) were prolonged for those treated with R-CHOP alone compared to CHOP alone (2-year FFS 76% versus 9%, P < .001; 2-year OS 79% versus 17%, P < .001). In contrast, no differences in FFS and OS were detected between treatment arms for Bcl-6(+) cases. In the multivariate analysis, treatment arm (CHOP versus R-CHOP) was the major determinant of both FFS (P < .001) and OS (P < .001) for the Bcl-6(-) subset, whereas the International Prognostic Index risk group was the only significant predictor of outcome among Bcl-6(+) cases. Bcl-2 protein expression was not predictive of outcome in either group. In this study, we observed a reduction in treatment failures and death with the addition of R to CHOP in Bcl-6(-) DLBCL cases only. Our finding that Bcl-6(+) cases did not benefit from the addition of R to CHOP requires independent confirmation.

Aged↗
PubMed2006

Thromboembolism in hospitalized neutropenic cancer patients.

PURPOSE: Cancer is associated with thrombosis, but the frequency of thromboembolism in hospitalized cancer patients receiving current chemotherapy regimens is not known. We investigated venous and arterial thromboembolism and associated outcomes in hospitalized cancer patients actively receiving therapy, as identified by neutropenia. METHODS: We conducted a retrospective cohort study using the discharge database of the University HealthSystem Consortium. This included 66,106 adult neutropenic cancer patients with 88,074 hospitalizations between 1995 and 2002 at 115 medical centers in the United States. RESULTS: Thromboembolism was reported in 5,272 patients (8%), with 5.4% patients developing venous thromboembolism and 1.5% developing arterial thromboembolism during the first hospitalization. Patients with lymphoma and leukemia accounted for one third of venous and nearly one half of arterial events. Clinical variables most frequently associated with thromboembolism were age > or = 65 years; primary site of cancer, including lung, GI, gynecologic, and brain; and comorbidities, including infection, pulmonary and renal disease, and obesity. In-hospital mortality was significantly greater in patients with venous (odds ratio [OR] = 2.01; 95% CI, 1.83 to 2.22) or arterial thromboembolism (OR = 5.04; 95% CI, 4.38 to 5.79). From 1995 to 2002, there was a 36% increase in venous events and a 124% increase in arterial events (P < .0001 for trend). CONCLUSION: Thromboembolism is frequent in hospitalized neutropenic cancer patients, including in perceived low-risk subgroups such as patients with hematologic malignancies and nonmetastatic disease, and seems to be increasing. Thromboembolism is associated with increased in-hospital mortality. Increased efforts at thromboprophylaxis are warranted.

Aged↗
PubMed2006

Venous thromboembolism in patients with diffuse large B-cell lymphoma.

We conducted a retrospective record review to determine the frequency of venous thromboembolism (VTE) in patients with diffuse large B-cell lymphoma (DLBCL). All records from 1990 to 2001 of patients with the diagnosis of DLBCL at a tertiary care hospital were reviewed. Those with transformation from low-grade lymphoma, central nervous system lymphoma, HIV-related lymphoma or with incomplete records were excluded. All episodes of symptomatic VTE confirmed by imaging studies that were either present at diagnosis or occurred during initial treatment were identified. VTE occurred in 27 of 211 patients (12.8%). Stage I disease was associated with a low risk, whereas a high international prognostic index score increased risk. Of patients with VTE, thrombosis was present at diagnosis in 37% and occurred during the first chemotherapy cycle in 22% and during the first three cycles in 82%. The median survival of patients with VTE was 1.04 years [95% confidence interval (CI) = 0.75 - 1.33] compared to 5.2 years (95% CI 1.8 - 8.6) for those without VTE (P = 0.038). We conclude that VTE is a frequent complication of DLBCL that occurs particularly at diagnosis and during initial therapy, and it is associated with a worse prognosis.

Adult↗
PubMed2006

The emerging concept of antigen-driven lymphomas: epidemiology and treatment implications.

PURPOSE OF REVIEW: Dramatic increases in the incidence of lymphomas worldwide have stimulated considerable efforts to identify factors that contribute to the etiology of this heterogeneous group of malignancies. The treatment and, ultimately, the prevention of lymphoma depend on our understanding of the complex interaction of exogenous agents with the molecular milieu which initiates and sustains a lymphoid malignancy. This review discusses the current evidence for the role of foreign or self antigens in the initiation of lymphomagenesis. RECENT FINDINGS: Recent data have demonstrated an increased risk of lymphoma among individuals with chronic inflammatory conditions, persistent infections or immunodeficient states. Common to these clinical conditions is antigenic stimulation leading to an inflammatory cascade of cellular and cytokine reactions that may tax the host immune response, provoke tissue injury and eventually result in lymphoid neoplasia. SUMMARY: Efforts to detect and suppress chronic, antigen-driven inflammation have suggested that neoplastic progression may often be interrupted and controlled. Elucidation of the etiologic mechanisms critical to the survival of these malignancies would provide promising alternatives for the prevention and treatment of some lymphomas.

Antigens↗
PubMed2006

Advances in the treatment of hematologic malignancies. Part 1 of a 3-part series: Aggressive lymphomas.

The treatment of patients with aggressive lymphomas has improved significantly in recent years, primarily due to the introduction of targeted therapy with the anti-CD20 monoclonal antibody rituximab in combination with chemotherapy. Rituximab has significantly improved overall survival and progression-free survival in patients with aggressive lymphomas, even those with high-risk disease. Ongoing research aims to determine the optimal uses of rituximab for inducing and maintaining remission in a variety of settings. Another important area of focus has been the investigation into prognostic and predictive factors. Assessing each patient according to different prognostic factors allows clinicians to best determine a patient's risk and develop a suitable therapy. Microarray analysis is being used in this area to determine gene expression patterns associated with responses to therapy and, ultimately, to identify specific genes associated with various outcomes. The identification of relevant genes could indicate specific patients that might benefit from targeted therapy, and may reveal additional therapeutic targets. These investigations have already identified several candidate genes that may be appropriate targets for therapy, such as Bcl-2, protein kinase C-beta, and nuclear factor-kappa B. The future of therapy for aggressive lymphomas will likely involve identifying the molecular profile for each patient and designing an appropriate targeted therapy based on their specific situation. Recent and ongoing studies are moving us closer towards that goal.

Antibodies, Monoclonal↗
PubMed2005

Loss of major histocompatibility class II expression in non-immune-privileged site diffuse large B-cell lymphoma is highly coordinated and not due to chromosomal deletions.

Decreased major histocompatibility class II (MHCII) expression is associated with poor survival in diffuse large B-cell lymphoma (DLBCL). Immune-privileged site DLBCL (IP-DLBCL) patients reportedly have frequent large deletions at the MHCII locus whereas the mechanism of decreased expression in non-IP-DLBCL is unknown. Gene expression profiling data were used for correlation analyses between expression levels of MHCII genes with each other and their transcriptional regulator, CIITA. Comparative genomic hybridization (CGH) assessed chromosomal alterations at MHCII-related loci. Finally, a map was created of expression of genes that are telomeric, within, or centromeric to the MHCII locus. Correlation coefficients among MHCII genes ranged from 0.73 to 0.92, whereas those between adjacent and intervening genes were lower (-0.12 to 0.49). Correlations between MHCII and CIITA expression were higher (0.53 to 0.60) than between CIITA and neighboring genes (-0.05 to 0.22). In 23 MHCII(-) cases, CGH detected 2 losses and 2 gains at MHCII loci. Expression of genes telomeric, within, and centromeric to MHCII loci were near normal in most MHCII(-) cases. Large deletions of the MHCII locus are uncommon in non-IP-DLBCL, implicating altered transcription as the operative mechanism for decreased expression.

Centromere↗
PubMed2005

New treatment options have changed the survival of patients with follicular lymphoma.

BACKGROUND: The natural history of follicular lymphoma is believed not to have changed over the last 30 years. Median survivals have ranged from 7 to 10 years, and the disease is considered incurable. However, multiple new treatment options have been developed in the last decade, and their impact on survival of follicular lymphoma remains unknown. PATIENTS AND METHODS: In the current analysis, we identified all previously untreated, advanced-stage, follicular lymphoma patients treated with the following three sequential treatment approaches: cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy +/- nonspecific immunostimulants (Southwest Oncology Group [SWOG] 7426 and 7713: 1974 to 1983); prednisone, methotrexate, doxorubicin, cyclophosphamide, and etoposide (ProMACE) plus mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) +/- interferon (SWOG 8809: 1988 to 1994); and CHOP followed by monoclonal antibody (MoAb) therapy (SWOG 9800 and 9911: 1998 to 2000). We assessed the patients' progression-free survival (PFS) and overall survival (OS). The MoAb trials included CHOP followed by rituximab (SWOG 9800) and CHOP followed by (131)I-tositumomab (SWOG 9911). RESULTS: The PFS curves for the CHOP and ProMACE-MOPP studies are overlapping, with 4-year PFS estimates of 46% and 48%, respectively. However, the PFS rate of the CHOP + MoAb studies is significantly improved at 61% (P = .005). The OS curves show improvement with each succeeding study. The 4-year estimate of OS is 69% for the CHOP regimens, 79% for the ProMACE-MOPP study, and 91% for the CHOP + MoAb regimens (P < .001). These conclusions were retained after adjusting for differences in prognostic factors between the study groups. CONCLUSION: The results of this study suggest that OS for patients with follicular lymphoma has improved over time and that the choice of initial therapy may matter.

Adolescent↗
PubMed2005

Tositumomab and iodine-131 tositumomab produces durable complete remissions in a subset of heavily pretreated patients with low-grade and transformed non-Hodgkin's lymphomas.

PURPOSE: This study is an integrated efficacy analysis of the five clinical trials of tositumomab and iodine-131 tositumomab in patients with relapsed or refractory low-grade, follicular, or transformed low-grade non-Hodgkin's lymphoma (NHL) that resulted in the regulatory approval of the iodine-131 tositumomab by the US Food and Drug Administration. PATIENTS AND METHODS: This integrated analysis included 250 patients. Patients received a single course of iodine-131 tositumomab. Responses were assessed by an independent panel of radiologists and oncologists. RESULTS: Response rates in the five trials ranged from 47% to 68%; complete response rates ranged from 20% to 38%. With a median follow-up of 5.3 years, the 5-year progression-free survival was 17%. Eighty-one (32%) of 250 patients had a time to progression of > or = 1 year (termed durable response population). For the durable response population, 44% had not progressed at > or = 2.5 to > or = 9.5 years and had a median duration of response of 45.8 months. The median duration of complete response was not reached. The durable response population had many poor prognostic characteristics, including bone marrow involvement (41%), bulky disease > or = 5 cm (49%), and transformed histology (23%). Forty-three percent of the patients had been treated with more than four prior therapies and 36% had not responded to their most recent therapy. CONCLUSION: The tositumomab and iodine-131 tositumomab therapeutic regimen produces high response rates in patients with relapsed or refractory low-grade, follicular, and transformed low-grade NHL, with a sizable subgroup of patients achieving long-term durable responses.

Adult↗
PubMed2005

Diffuse large B-cell lymphoma subgroups have distinct genetic profiles that influence tumor biology and improve gene-expression-based survival prediction.

Gene-expression profiling has identified 3 major subgroups of diffuse large B-cell lymphoma (DLBCL): germinal center B-cell-like (GCB), activated B-cell-like (ABC), and primary mediastinal DLBCL (PMBCL). Using comparative genomic hybridization (CGH), we investigated the genetic alterations of 224 cases of untreated DLBCL (87 GCB-DLBCL, 77 ABC-DLBCL, 19 PMBCL, and 41 unclassified DLBCL) previously characterized by gene-expression profiling. The DLBCL subgroups differed significantly in the frequency of particular chromosomal aberrations. ABC-DLBCL had frequent trisomy 3, gains of 3q and 18q21-q22, and losses of 6q21-q22, whereas GCB-DLBCL had frequent gains of 12q12, and PMBCL had gains of 9p21-pter and 2p14-p16. Parallel analysis of CGH alterations, locus-specific gene-expression profiles, and global gene-expression signatures revealed that DNA amplifications and gains had a substantial impact on the expression of genes in the involved chromosomal regions, and some genes were overexpressed in a DLBCL subgroup-specific fashion. Unexpectedly, specific chromosomal alterations were associated with significant changes in gene-expression signatures that reflect various aspects of lymphoma cell biology as well as the host response to the lymphoma. In addition, gains involving the chromosomal region 3p11-p12 provided prognostic information that was statistically independent of the previously defined gene-expression-based survival model, thereby improving its predictive power.

Chromosomes, Human↗
PubMed2005

Alteration of SMRT tumor suppressor function in transformed non-Hodgkin lymphomas.

Indolent non-Hodgkin lymphomas are characterized by a prolonged phase that is typically followed by a clinical progression associated with an accelerated clinical course and short survival time. Previous studies have not identified a consistent cytogenetic or molecular abnormality associated with transformation. The development of a transformed phenotype, evolving from the original low-grade component, most likely depends on multiple genetic events, including the activation of synergistic dominant oncogenes and a loss of tumor suppressor gene functions. Complex karyotypes and relatively bad chromosome morphology are typical of transformed non-Hodgkin lymphomas, rendering complete cytogenetic analysis difficult. Here, we report the use of transformed non-Hodgkin lymphoma cell lines and primary samples to identify the involvement of the silencing mediator of retinoic acid and thyroid hormone receptor (SMRT) gene that maps at chromosome 12q24 in transformed non-Hodgkin lymphomas. We also show that down-regulation of SMRT in the immortalized "Weinberg's model" cell lines induces transformation of the cells. Assessment of cDNA array profiles should further help us to design a working model for SMRT involvement in non-Hodgkin lymphoma transformation as a novel, nonclassical tumor suppressor.

Apoptosis↗