Rituximab Chimeric Anti-CD20 Monoclonal Antibody Therapy for Relapsed Indolent Lymphoma: Half of Patients Respond to a Four-Dose Treatment Program.

PURPOSE: The CD20 antigen is expressed on more than 90% of B-cell lymphomas. It is appealing for targeted therapy, because it does not shed or modulate. A chimeric monoclonal antibody more effectively mediates host effector functions and is itself less immunogenic than are murine antibodies. PATIENTS AND METHODS: This was a multiinstitutional trial of the chimeric anti-CD20 antibody, IDEC-C2B8. Patients with relapsed low grade or follicular lymphoma received an outpatient treatment course of IDEC-C2B8 375 mg/m2 intravenously weekly for four doses. RESULTS: From 31 centers, 166 patients were entered. Of this intent-to-treat group, 48% responded. With a median follow-up duration of 11.8 months, the projected median time to progression for responders is 13.0 months. Serum antibody levels were sustained longer after the fourth infusion than after the first, and were higher in responders and in patients with lower tumor burden. The majority of adverse events occurred during the first infusion and were grade 1 or 2; fever and chills were the most common events. Only 12% of patients had grade 3 and 3% grade 4 toxicities. A human antichimeric antibody was detected in only one patient. CONCLUSION: The response rate of 48% with IDEC-C2B8 is comparable to results with single-agent cytotoxic chemotherapy. Toxicity was mild. Attention needs to be paid to the rate of antibody infusion, with titration according to toxicity. Further investigation of this agent is warranted, including its use in conjunction with standard chemotherapy.

Erector spinae plane block vs. peri-articular injection for pain control after arthroscopic shoulder surgery: a randomised controlled trial.

Interscalene brachial plexus block is the standard regional analgesic technique for shoulder surgery. Given its adverse effects, alternative techniques have been explored. Reports suggest that the erector spinae plane block may potentially provide effective analgesia following shoulder surgery. However, its analgesic efficacy for shoulder surgery compared with placebo or local anaesthetic infiltration has never been established. We conducted a randomised controlled trial to compare the analgesic efficacy of pre-operative T2 erector spinae plane block with peri-articular infiltration at the end of surgery. Sixty-two patients undergoing arthroscopic shoulder repair were randomly assigned to receive active erector spinae plane block with saline peri-articular injection (n = 31) or active peri-articular injection with saline erector spinae plane block (n = 31) in a blinded double-dummy design. Primary outcome was resting pain score in recovery. Secondary outcomes included pain scores with movement; opioid use; patient satisfaction; adverse effects in hospital; and outcomes at 24 h and 1 month. There was no difference in pain scores in recovery, with a median difference (95%CI) of 0.6 (-1.9-3.1), p = 0.65. Median postoperative oral morphine equivalent utilisation was significantly higher in the erector spinae plane group (21 mg vs. 12 mg; p = 0.028). Itching was observed in 10% of patients who received erector spinae plane block and there was no difference in the incidence of significant nausea and vomiting. Patient satisfaction scores, and pain scores and opioid use at 24 h were similar. At 1 month, six (peri-articular injection) and eight (erector spinae plane block) patients reported persistent pain. Erector spinae plane block was not superior to peri-articular injection for arthroscopic shoulder surgery.

A comprehensive review of lenalidomide therapy for B-cell non-Hodgkin lymphoma.

Lenalidomide is an oral non-chemotherapy immunomodulator with direct and indirect effects on non-Hodgkin lymphoma (NHL) cells and with single-agent activity in relapsed/refractory aggressive and indolent B-cell NHL, including mantle cell lymphoma (MCL), diffuse large B-cell lymphoma, and follicular lymphoma. Based on the pivotal phase II MCL-001 trial of lenalidomide in heavily pretreated patients with relapsed/refractory MCL, lenalidomide was approved by the US Food and Drug Administration for the treatment of relapsed/refractory MCL after failure of two prior therapies, one of which includes bortezomib, at a recommended starting dose of 25 mg on days 1-21 of each 28-day cycle. Lenalidomide enhanced the survival benefit in combination with rituximab in preclinical models, prompting clinical evaluation of the lenalidomide-rituximab (R2) combination. In phase II trials, lenalidomide 20 mg on days 1-21 in combination with different standard-dose rituximab schedules exhibited promising activity in both first-line and relapsed/refractory disease across multiple B-cell NHL subtypes. The feasibility of combining lenalidomide with immunochemotherapy, including R-CHOP and rituximab-bendamustine, has been demonstrated in phase I/II trials. These latter regimens are currently being evaluated in ongoing phase II and III trials. The role of lenalidomide monotherapy and R2 in maintenance therapy is also being examined. Based on available evidence, a comprehensive review of lenalidomide in all treatment phases of B-cell NHL-relapsed/refractory disease, first-line, and maintenance-is presented here.

Anti-CD22 and anti-CD79B antibody drug conjugates are active in different molecular diffuse large B-cell lymphoma subtypes.

Antibody drug conjugates (ADCs), in which cytotoxic drugs are linked to antibodies targeting antigens on tumor cells, represent promising novel agents for the treatment of malignant lymphomas. Pinatuzumab vedotin is an anti-CD22 ADC and polatuzumab vedotin an anti-CD79B ADC that are both linked to the microtubule-disrupting agent monomethyl auristatin E (MMAE). In the present study, we analyzed the activity of these agents in different molecular subtypes of diffuse large B-cell lymphoma (DLBCL) both in vitro and in early clinical trials. Both anti-CD22-MMAE and anti-CD79B-MMAE were highly active and induced cell death in the vast majority of activated B-cell-like (ABC) and germinal center B-cell-like (GCB) DLBCL cell lines. Similarly, both agents induced cytotoxicity in models with and without mutations in the signaling molecule CD79B. In line with these observations, relapsed and refractory DLBCL patients of both subtypes responded to these agents. Importantly, a strong correlation between CD22 and CD79B expression in vitro and in vivo was not detectable, indicating that patients should not be excluded from anti-CD22-MMAE or anti-CD79B-MMAE treatment because of low target expression. In summary, these studies suggest that pinatuzumab vedotin and polatuzumab vedotin are active agents for the treatment of patients with different subtypes of DLBCL.

Long-term follow-up of lenalidomide in relapsed/refractory mantle cell lymphoma: subset analysis of the NHL-003 study.

BACKGROUND: Mantle cell lymphoma (MCL) is an uncommon type of non-Hodgkin lymphoma with poor overall prognosis, requiring the development of new therapies. Lenalidomide is an immunomodulatory agent demonstrating antitumor and antiproliferative effects in MCL. We report results from a long-term subset analysis of 57 patients with relapsed/refractory MCL from the NHL-003 phase II multicenter study of single-agent lenalidomide in patients with aggressive lymphoma DESIGN: Lenalidomide was administered orally 25 mg daily on days 1-21 every 28 days until progressive disease (PD) or intolerability. The primary end point was overall response rate (ORR). RESULTS: Fifty-seven patients with relapsed/refractory, advanced-stage MCL had a median of three prior therapies. The ORR was 35% [complete response (CR)/CR unconfirmed (CRu) 12%], with a median duration of response (DOR) of 16.3 months (not yet reached in patients with CR/CRu) by blinded independent central review. The median time to first response was 1.9 months. Median progression-free survival was 8.8 months, and overall survival had not yet been reached. The most common grade 3/4 adverse events (AEs) were neutropenia (46%), thrombocytopenia (30%), and anemia (13%). CONCLUSIONS: These results show the activity of lenalidomide in heavily pretreated, relapsed/refractory MCL. Responders had a durable response with manageable side-effects. Clinical trial number posted on www.clinicaltrials.gov NCT00413036.

Phase II trial of galiximab (anti-CD80 monoclonal antibody) plus rituximab (CALGB 50402): Follicular Lymphoma International Prognostic Index (FLIPI) score is predictive of upfront immunotherapy responsiveness.

BACKGROUND: This phase II CALGB trial evaluated the activity and safety of an extended induction schedule of galiximab (G) plus rituximab (R) in untreated follicular lymphoma (FL). PATIENTS AND METHODS: Patients with previously untreated FL (grades 1, 2, 3a) received 4 weekly infusions of G + R, followed by an additional dose every 2 months four times. International Workshop Response Criteria were used to evaluate response. RESULTS: Sixty-one patients were treated and antibody infusions were well tolerated. The overall response rate (ORR) is 72.1% (95% confidence interval 59.2% to 82.9%): 47.6% complete response (CR)/unconfirmed complete response (CRu) and 24.6% partial response. At a median follow-up time of 4.3 years (range, 0.3-5.3 years) median progression-free survival (PFS) is 2.9 years. Notably, Follicular Lymphoma International Prognostic Index (FLIPI) correlated with ORR, CR rate, and PFS, and the low-risk FLIPI group (n = 12) achieved a 92% ORR, 75% CR/CRu rate, and 75% 3-year PFS. CONCLUSIONS: An extended induction schedule of G + R in previously untreated FL is well tolerated and appears particularly efficacious in those patients with low-risk FLIPI scores. In addition, this trial served as the initial platform for additional CALGB 'doublet' combination regimes of rituximab plus other novel targeted agents.

An international phase II trial of single-agent lenalidomide for relapsed or refractory aggressive B-cell non-Hodgkin's lymphoma.

BACKGROUND: Lenalidomide is an immunomodulatory agent with antitumor activity in B-cell malignancies. This phase II trial aimed to demonstrate the safety and efficacy of lenalidomide in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL), mantle cell lymphoma (MCL), follicular grade 3 lymphoma (FL-III), or transformed lymphoma (TL). METHODS: Patients received oral lenalidomide 25 mg on days 1-21 every 28 days as tolerated or until progression. The primary end point was overall response rate (ORR). RESULTS: Two hundred and seventeen patients enrolled and received lenalidomide. The ORR was 35% (77/217), with 13% (29/217) complete remission (CR), 22% (48/217) partial remission, and 21% (45/217) with stable disease. The ORR for DLBCL was 28% (30/108), 42% (24/57) for MCL, 42% (8/19) for FL-III, and 45% (15/33) for TL. Median progression-free survival for all 217 patients was 3.7 months [95% confidence interval (CI) 2.7-5.1]. For 77 responders, the median response duration lasted 10.6 months (95% CI 7.0-NR). Median response duration was not reached in 29 patients who achieved a CR and in responding patients with FL-III or MCL. The most common adverse event was myelosuppression with grade 4 neutropenia and thrombocytopenia in 17% and 6%, respectively. CONCLUSION: Lenalidomide is well tolerated and produces durable responses in patients with relapsed or refractory aggressive non-Hodgkin's lymphoma.

A Phase 1b/2 trial of mapatumumab in patients with relapsed/refractory non-Hodgkin's lymphoma.

BACKGROUND: we conducted a multicentre Phase 1b/2 trial to evaluate the safety and efficacy of mapatumumab, a fully human agonistic monoclonal antibody to the tumour necrosis factor-related apoptosis-inducing ligand receptor 1 (TRAIL-R1) in patients with relapsed non-Hodgkin's lymphoma (NHL). METHODS: forty patients with relapsed or refractory NHL were treated with either 3 or 10 mg kg(-1) mapatumumab every 21 days. In the absence of disease progression or prohibitive toxicity, patients received a maximum of six doses. RESULTS: mapatumumab was well tolerated, with no patients experiencing drug-related hepatic or other dose-limiting toxicity. Three patients with follicular lymphoma (FL) experienced clinical responses, including two with a complete response and one with a partial response. Immunohistochemistry staining of the TRAIL-R1 suggested that strong staining in tumour specimens did not appear to be a requirement for mapatumumab activity in FL. CONCLUSIONS: mapatumumab is safe and has promising clinical activity in patients with FL.

Enhancing activity and overcoming chemoresistance in hematologic malignancies with bortezomib: preclinical mechanistic studies.

BACKGROUND: Proteasome inhibition results in antitumor activity through various mechanisms, including disruption of cell cycle progression and control, induction of apoptosis, and inhibition of proliferation. DESIGN: This review assesses preclinical data on the ability of bortezomib, the first proteasome inhibitor approved for clinical use, to enhance antitumor activity of other agents and to overcome chemoresistance in hematologic malignancies and discusses mechanisms by which such activity arises. RESULTS: Bortezomib has been shown to affect multiple cellular pathways and levels of numerous intracellular proteins, including targets of importance in hematologic malignancies. These mechanisms have shown additive or synergistic effects in vitro and in vivo with those of conventional therapeutic and novel targeted agents. Additionally, targets of proteasome inhibition are implicated in resistance or lack of sensitivity to different therapies. Bortezomib in combination with other agents has been shown to overcome resistance to those agents and to resensitize cells to agents to which they were previously unresponsive. CONCLUSIONS: This review indicates the potential utility of proteasome inhibition for substantially enhancing activity of other therapeutic approaches. It explains the mechanisms responsible for the observed clinical activity of bortezomib-based regimens and elucidates novel therapeutic approaches through identification of combinations of agents with complimentary mechanisms of action.

Novel antibodies in the treatment of non-Hodgkin's lymphoma.

Monoclonal antibodies (mAbs) have revolutionised the treatment of malignancies, especially non-Hodgkin's lymphoma (NHL). Antibody-based therapies target tumour cells expressing a specific antigen while sparing the majority of normal cells leading to a decrease in treatment-associated toxicity. Rituximab, a monoclonal antibody directed against CD20 on B cells, was the first monoclonal antibody to be approved by the US Food and Drug Association (FDA) in 1997 for the treatment of patients with relapsed/refractory, follicular or low-grade NHL . However, it was soon realised that not all patients respond to rituximab therapy and close to 60% of patients with follicular lymphoma who were previously sensitive to rituximab become 'resistant' to repeat rituximab therapy. This led to further attempts to improve the antitumour activity of anti-CD20 mAbs (i.e. 2nd/3rd generation anti-CD20s), and to identify additional potential targets on lymphoma cells other than CD20. A number of these antibodies directed against lymphoma cell targets other than CD20 are now undergoing development, many of which are currently in clinical trials. This manuscript focuses on an overview of these 'non-anti-CD20' novel mAbs for NHL.

Intensive conditioning regimen of etoposide (VP-16), cyclophosphamide and carmustine (VCB) followed by autologous hematopoietic stem cell transplantation for relapsed and refractory Hodgkin's lymphoma.

Several high-dose therapy regimens are used for autologous hematopoietic stem cell transplantation (auto-HSCT) for relapsed and refractory Hodgkin's lymphoma (HL) with variable disease response. An intensified regimen of etoposide (VP-16) 2,400 mg/m(2), cyclophosphamide 7,200 mg/m(2) and carmustine (BCNU) 600 mg/m(2) (VCB) pre-auto-HSCT was developed to overcome disease recurrence. A total of 43 relapsed and refractory HL patients underwent auto-HSCT between January 1992 and December 2004. At day 100 there were 37 (86%) complete responses. A total of 40 patients survived beyond day 100, 14 of whom subsequently relapsed/progressed. At a median follow-up of 4.9 years (range 1.5-11.4 years), 26 patients (60%) are alive and disease free. Five-year actuarial event-free survival (EFS) was 53% (95% CI 35-70%) and median EFS was 5.9 years. Median progression-free and overall survivals have not been reached. EFS was reduced with an increasing number of prognostic factors (Karnofsky performance status, KPS <90, chemotherapy-resistant disease and >or=3 chemotherapy regimens prior to transplant or=2; P=0.049). Grade III-IV regimen-related toxicity was 9% (n=4). The 1-year cumulative incidence of interstitial pneumonitis (IP) was 36%, however only two patients died of IP complications. Disease progression was the most common cause of death (n=10, 23%). Intensive VCB is an effective and well-tolerated preparative regimen for relapsed and refractory HL auto-HSCT.

A phase I/II study of galiximab (an anti-CD80 monoclonal antibody) in combination with rituximab for relapsed or refractory, follicular lymphoma.

BACKGROUND: Galiximab is a monoclonal antibody that targets CD80, a costimulatory molecule constitutively expressed on follicular and other lymphomas. Modest single-agent clinical activity and tolerability were demonstrated in a phase I study in relapsed or refractory, follicular non-Hodgkin's lymphoma (NHL). A phase I/II study was conducted to evaluate galiximab in combination with a standard course of rituximab. Safety, pharmacokinetics, and efficacy were evaluated. PATIENTS AND METHODS: Patients with follicular NHL who had relapsed or failed primary therapy were enrolled. Rituximab-refractory patients (no response or a response with time to progression <6 months) were excluded. Patients received 4 weekly i.v. infusions of galiximab (125, 250, 375, or 500 mg/m(2)) and rituximab (375 mg/m(2)). International Workshop Response Criteria (IWRC) were used to evaluate response. RESULTS: Seventy-three patients received treatment. All had received at least one prior lymphoma therapy; 40% were rituximab naive. Infusions were delivered in an outpatient setting and were well tolerated. The most common study-related adverse events (AE) were lymphopenia, leukopenia, neutropenia, fatigue, and chills. The overall response rate at the recommended phase II dose of galiximab (500 mg/m(2)) was 66%: 19% complete response, 14% unconfirmed complete response, and 33% partial response. The median progression free survival was 12.1 months. Combination therapy did not appear to alter pharmacokinetics. CONCLUSION: These results indicate that galiximab can be safely combined with a standard course of rituximab. This doublet biologic approach offers the potential to avoid or delay chemotherapy or to integrate with other lymphoma therapies. A phase III, randomized study evaluating clinical benefit of rituximab versus the combination has been initiated.

Prognostic factors for non-Hodgkin's lymphoma patients treated with chemotherapy may not predict outcome in patients treated with rituximab.

Several factors predict outcome for patients with non-Hodgkin's lymphoma (NHL) after chemotherapy. However, predictors of response to rituximab have not been identified. Baseline characteristics for 166 NHL patients (130 follicular) in a phase III trial of rituximab were analysed by univariate and multivariate methods to determine whether any of 27 factors predict response and/or response duration. In a univariate analysis, response to rituximab was associated with follicular histology, no prior fludarabine therapy, prior autologous bone marrow transplantation (ABMT), lack of bone marrow involvement or extranodal disease, positive bcl-2 in blood, and fewer relapses. By univariate analysis, longer median time to progression (TTP) and/or duration of response (DR) after rituximab therapy was associated with International Prognostic Index lower-risk group, multiagent chemotherapy, and low/normal serum lactate dehydrogenase (LDH) or beta2 microglobulin. In the multivariate analysis, response to rituximab correlated with follicular histology, prior ABMT, multiagent chemotherapy, and no bone marrow involvement; longer TTP and/or DR correlated with low/normal serum LDH or beta2 microglobulin, high CD3+ cells, and response to last chemotherapy. The follicular lymphoma international prognostic index (FLIPI) did not correlate consistently with response to rituximab or response duration. Several factors associated with prognosis following chemotherapy did not correlate with response to rituximab or response duration. NHL patients can respond to rituximab despite having factors associated with a poor outcome to chemotherapy.

Long-term update of a phase II study of rituximab in combination with CHOP chemotherapy in patients with previously untreated, aggressive non-Hodgkin's lymphoma.

The present study aimed to determine the long-term safety and efficacy of chimeric anti-CD 20 antibody rituxan (rituximab, Biogen IDEC, San Diego, CA, USA; Genentech, South San Francisco, CA, USA) in combination with cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) chemotherapy in previously untreated patients with aggressive non-Hodgkin's lymphoma (NHL). Thirty-three patients with previously untreated aggressive B-cell NHL received six infusions of rituximab (375 mg/m(2) per dose) on day 1 of each cycle of CHOP chemotherapy, given on day 3 of each cycle of therapy. Currently, the patients now have a median follow-up of 63 months (range 34 - 82 months). The overall response (OR) rate was 94% and the complete response (CR) rate was 61% at the end of therapy. Of the 33 patients, 2 patients experienced disease progression and subsequently died of their disease, 2 patients experienced disease progression but were alive at last follow-up following additional therapy, and 2 patients died without experiencing disease progression: one due to a cerebral vascular accident at 9 months after therapy and a second patient due to small cell lung carcinoma at 55 months. The 5-year survival rate was 88% (95% confidence interval (CI) 72 - 97) and the 5-year progression-free survival was 82% (95% CI 64 - 93). There were no long-term adverse events noted directly related to the rituximab. The long-term follow-up of patients in this phase II trial of rituximab with CHOP chemotherapy for previously untreated aggressive NHL demonstrates a high response rate, which remains very durable with high 5-year overall and progression-free survivals.

Rituximab in combination with fludarabine chemotherapy in low-grade or follicular lymphoma.

PURPOSE: To evaluate the safety and efficacy of fludarabine plus rituximab in treatment-naive or relapsed patients with low-grade and/or follicular non-Hodgkin's lymphoma. PATIENTS AND METHODS: This was an open-label, single-arm, single-center phase II study enrolling 40 patients. During the first week of the study, patients received two infusions of rituximab 375 mg/m2 administered 4 days apart. Seventy-two hours after the second infusion of rituximab, patients received the first of six cycles of fludarabine chemotherapy (25 mg/m2/d for 5 days on a 28-day cycle). Single infusions of rituximab were administered 72 hours before the second, fourth, and sixth cycles of fludarabine, and two infusions of rituximab were given 4 weeks after the last cycle of fludarabine. Treatment duration was 26 weeks. RESULTS: An overall response rate of 90% (80% complete response rate) was achieved in the intent-to-treat population. Similar response rates were seen in treatment-naive and previously treated patients. The median duration of response has not been reached at 40+ months. The median follow-up time in this study is 44 months (range, 15 to 66 months). In patients positive for the 14;18 translocation in blood and/or marrow at enrollment, molecular remission was achieved in 88% of cases, with patients remaining negative for up to 4 years to date. Hematologic toxicity was manageable, and except for a 15% incidence of herpes simplex/zoster infections, infectious complications were rare. Nonhematologic toxicities were minimal. CONCLUSION: Rituximab plus fludarabine was well tolerated and associated with an excellent complete response rate, including molecular remissions, in patients with low-grade or follicular lymphoma.

A prognostic model for prolonged event-free survival after autologous or allogeneic blood or marrow transplantation for relapsed and refractory Hodgkin's disease.

There are several prognostic models for Hodgkin's disease (HD) patients, but none evaluating patient characteristics at time of blood and marrow transplantation (BMT). We developed a prognostic model for event-free survival (EFS) post-BMT based on HD patient characteristics measured at the time of autologous (auto) or allogeneic (allo) BMT. Between 1/1991 and 12/2001, 64 relapsed or refractory HD patients received an auto (n=46) or allo (n=18) BMT. A multivariate prognostic model was developed measuring time to relapse, progression or death. Median follow-up was 51.7 months; median EFS for auto and allo BMT was 36 and 3 months, respectively (P=0.001). Significant multivariate predictors of shorter EFS were chemotherapy-resistant disease, KPS <90 and > or =3 chemotherapy regimens pre-BMT. Patients with two to three adverse factors had significantly shorter EFS at 2 years (58 vs 11% in auto; 38 vs 0% in allo BMT patients). Despite a selection bias favoring auto BMT, the model was valid in both auto and allo BMT groups. We were able to differentiate patients at high vs low risk for adverse outcomes post-BMT. This prognostic model may prove useful in predicting patient outcomes and identifying high-risk patients for novel treatment strategies. Validation of this model in a larger cohort of patients is warranted.

Acute renal failure requiring dialysis after allogeneic blood and marrow transplantation identifies very poor prognosis patients.

We examined the incidence, risk factors and associated mortality of acute renal failure requiring dialysis (Renal Bearman Grade [BG] 3) in a 3-year cohort of 97 consecutive allogeneic blood and marrow transplantation (alloBMT) patients. In all, 20 (21%) developed Renal BG3 (all died by day +132) and 77 (79%) developed renal insufficiency (Renal BG1-2). Renal BG3 was a contributing or primary cause of death in 18 (90%) patients who continued to require dialysis at time of death. The two Renal BG3 patients whose deaths were not related to renal failure died on day +103 of hemorrhage and day +132 of underlying disease. By univariate analysis, age, unrelated donor, veno-occlusive disease (VOD) and grade III-IV acute graft-versus-host disease with hepatic involvement were significantly associated with Renal BG3. The multivariate model of time to Renal BG3 determined only a prior diagnosis of severe acute GVHD (RR=4.1, 95% CI 1.6-10.3, P=0.003) and VOD (RR=9.1, 95% CI 3.5-23.7, P<0.001) as significant independent predictors. Renal BG3 is generally considered a conditioning regimen-related toxicity. This study demonstrates that Renal BG3 is most commonly a complication of hepatic co-morbidities after allogeneic blood and marrow transplantation and identifies patients with a very poor prognosis.

Effect of rituximab on peripheral blood stem cell mobilization and engraftment kinetics in non-Hodgkin's lymphoma patients.

Rituximab is used for in vivo tumor cell purging for non-Hodgkin's lymphoma (NHL) patients prior to autologous peripheral blood stem cell transplantation (PBSCT). However, its effects on PBSC mobilization and function are poorly understood. We compared the mobilization characteristics and engraftment kinetics of 13 NHL patients receiving and 34 NHL patients not receiving rituximab 6 months before PBSC mobilization. In the rituximab group, there was a significantly longer time to neutrophil engraftment (P=0.0466), a trend toward the need for BM harvest to supplement low-yield PBSC collections (31 vs 9%, P=0.08) and a significantly increased rate of bacteremia episodes (62 vs 26%, P=0.025). Median progression-free survival (PFS) and overall survival (OS) were significantly longer in the rituximab compared to the nonrituximab patients (P=0.049 and 0.042, respectively). However, patients in the nonrituximab group were at high risk for recurrence and expected to have shorter survival. Rituximab used within 6 months prior to collection may have a detrimental effect on PBSC mobilization and engraftment. However, rituximab is a major therapeutic breakthrough for NHL treatment and this negative effect may be offset by improved survival. Further studies are warranted in larger populations to determine the impact of rituximab on engraftment, PFS and OS.

Radioimmunoscintigraphy (RIS) with bectumomab (Tc99m labeled IMMU-LL2, Lymphoscan) in the assessment of recurrent non-Hodgkin's lymphoma (NHL).

UNLABELLED: The efficacy of a Tc99m-labeled anti-lymphoma antibody fragment, bectumomab [LymphoScan], was retrospectively examined in the staging of recurrent or newly diagnosed non-Hodgkin's lymphoma (NHL) [7 patients] and to assess targeting before radioimmunotherapy (RIT) [14 patients]. Performance was graded relative to conventional imaging. Tumors included 7 low-grade, 11 intermediate-grade, and 3 high-grade histologic subtypes. Computed x-ray tomography, radiogallium imaging, FDG-PET, and bone marrow biopsy defined 117 sites. Bectumomab revealed 56% of these sites. In 4 patients bectumomab uncovered five sites not evident by conventional imaging. In addition, it uncovered one site in the brain, an area not covered in the standard work-up of asymptomatic patients. Bectumomab imaging most often failed in central abdominal and thoracic locations, and excelled in revealing disease in the head and neck. Relative to Ga67 citrate imaging, the performance of bectumomab was variable, with no clear relation to anatomic location; there was better targeting of low and intermediate grade NHL. Radiogallium out-performed bectumomab imaging in 23 sites, 19 of which were in patients with high or intermediate-grade disease. Bectumomab was superior to radiogallium at six sites, five of which involved low-grade tumor. CONCLUSION: Bectumomab shows promise as a pre-RIT probe for targeting of B-cell NHL. It excelled at defining small volume, low-grade disease. However, as a purely diagnostic agent, its performance was variable.