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K Tobinai

Publications and source records attributed to K Tobinai.

At least 19 recordsLinked to original sources

Clinicopathological features of pyothorax-associated lymphoma; a retrospective survey involving 98 patients.

To investigate clinicopathological features of pyothorax-associated lymphoma (PAL), we examined medical records of 98 patients (88 males and 10 females) with PAL at a median age of 70 years (range 51-86). Seventy-nine patients had a history of artificial pneumothorax. Median interval between diagnosis and artificial pneumothorax was 43 years (range 19-64). At diagnosis, performance status (PS) was 0-1 (n=56) and 2-4 (n=42). Clinical stages were I (n=42), II (n=26), III (n=8) and IV (n=22). Pathological diagnosis comprised diffuse large-B-cell (n=78) and peripheral T-cell lymphoma (n=1). Seventeen were treated supportively. The other 81 received aggressive treatments; chemotherapy (n=52), radiotherapy (n=7), surgery (n=4) and combination (n=18). Five-year overall survival (OS) was 0.35 (95% confidence interval, 24% to 45%). Causes of deaths were PAL (n=39), respiratory failure (n=13) and others (n=12). Multivariate analysis identified prognostic factors for OS; lactate dehydrogenase levels [hazard ratio (HR)=2.36; P=0.013], sex (female versus male) (HR=0.15; P=0.01), PS (2-4 versus 0-1) (HR=2.20; P=0.02), clinical stages (III/IV versus I/II) (HR=1.95; P=0.037) and chemotherapy (HR=0.31; P=0.01). Most patients with PAL are elderly and have comorbidities, while some of them achieve durable remission with appropriate treatments. These findings prompt us to establish an optimal treatment strategy on the basis of risk stratification of individual patients.

Aged↗

Phase I and pharmacokinetic study of oral fludarabine phosphate in relapsed indolent B-cell non-Hodgkin's lymphoma.

BACKGROUND: The primary objective of this study was to investigate the tolerability, efficacy and pharmacokinetic profile of oral fludarabine phosphate in relapsed patients with indolent B-cell non-Hodgkin's lymphoma (B-NHL). PATIENTS AND METHODS: Patients received fludarabine phosphate orally for 5 days, for a total of one to three cycles. Tolerability was assessed using the National Cancer Institute Common Toxicity Criteria. Efficacy was assessed using the International Workshop Criteria for NHL. Pharmacokinetic samples were taken on day 1 and day 5 of the first treatment cycle. RESULTS: Twelve patients were enrolled. One patient at 40 mg/m2/day developed grade 4 hyperuricemia. At 50 mg/m2/day, one patient developed grade 3 febrile neutropenia and grade 4 leukopenia, and another patient showed lasting grade 4 neutropenia. Most common toxicities included grade 3 or 4 lymphopenia (83%), leukopenia (50%) and neutropenia (50%). All the toxicities were reversible. The overall response rate was 67%. The AUC0-24h values on day 5 indicated a dose-dependent increase in systemically available 2-fluoro-arabinofuranosyl-adenine (2F-ara-A). CONCLUSIONS: Oral fludarabine phosphate is safe and effective for relapsed patients with indolent B-NHL. The dose of 40 mg/m2/day is recommended for a following pivotal phase II study.

Administration, Oral↗

Long-term follow-up results of no initial therapy for ocular adnexal MALT lymphoma.

BACKGROUND: The majority of lymphomas in the ocular adnexa are low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT lymphoma). Although radiotherapy is the most frequently applied management, cataract and dry eye are problematic complications. PATIENTS AND METHODS: Between 1973 and 2003, the clinical features of 36 patients with ocular adnexal MALT lymphoma with no symptoms who were managed with no initial therapy after biopsy or surgical resection were retrospectively analyzed. RESULTS: The median patient age was 63 years (range 22-84) and all patients had stage I disease, consisting of 31 unilateral cases and five bilateral cases. With a median follow-up of 7.1 years, 25 (69%) did not require treatment. The median time until the initiation of treatment in the remaining 11 patients (31%) was 4.8 years. Six patients (17%) died, and among them only two (6%) died due to progressive lymphoma. Seventeen patients (47%) progressed, but histologic transformation was recognized in only one (3%). The estimated overall survival rates of the 36 patients after 5, 10 and 15 years were 94%, 94% and 71%, respectively. CONCLUSIONS: In selected patients with ocular adnexal MALT lymphoma, no initial therapy might be an acceptable approach, because 70% of patients remained untreated at a median of 8.6 years, and their survival was comparable to that of reports on immediate therapy.

Adult↗

Isolation and transplantation of highly purified autologous peripheral CD34+ progenitor cells: purging efficacy, hematopoietic reconstitution in non-Hodgkin's lymphoma (NHL): results of Japanese phase II study.

The purging efficacy of positive selection of autologous CD34+ PBSC with a clinical scale method of magnetic-activated cell sorting system (CliniMACS) was investigated in 48 patients with non-Hodgkin's lymphoma (NHL). The median purity and recovery rate of the CD34+ cells post-selection were 93.3% (range 32.6-99.3) and 72.2% (range 20.5-309.8), respectively. The real-time PCR method to detect the patient-specific monoclonal immunoglobulin heavy chain gene rearrangement (minimal residual tumor; MRT) and CD19 and CD20 positivities were used for the detection of contaminating NHL cells before and after CD34+ selection. After selection, the median (range) depletion rate of MRT was 2.53 (1.52-4.78) log, and that of CD19+ cell and CD20+ cell was 2.46 (0.74-3.64) log and 2.32 (0.40-4.01) log, respectively. In 41 patients, high-dose chemotherapy was performed, followed by the transplantation of the isolated CD34+ cells. Rapid neutrophil recovery as well as platelet recovery was seen with a median time to reach 0.5 x 10(9)/l neutrophils of 10 days (range 8-13) and 20 x 10(9)/l platelets of 14 days (range 10-34), respectively. The present study demonstrated that CliniMACS is a highly effective positive selection method and a high purging efficacy could be obtained without compromising the hematopoietic reconstitution capacity of the graft in NHL patients undergoing high-dose chemotherapy.

Adult↗

Reduced-intensity stem cell transplantation from an HLA-identical sibling donor in patients with myeloid malignancies.

The purpose of this study was to evaluate the feasibility and efficacy of allogeneic hematopoietic stem cell transplantation with a reduced-intensity regimen (RIST) in patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS). In all, 36 patients (median age 55 years) underwent RIST from an HLA-matched related donor between September 1999 and December 2002. The diagnoses included AML (n=14), leukemia evolving from MDS (n=10), and MDS (refractory anemia with excess blasts n=6, refractory anemia n=6). The RIST regimen consisted of purine analog (cladribine or fludarabine)/busulfan, with or without antithymocyte globulin. The regimen was well tolerated, and 34 patients achieved durable engraftment and most achieved remission after RIST. A total of 17 patients developed grade II-IV acute GVHD, and 27 developed chronic GVHD. Eight patients relapsed, and five of them received antithymocyte globulin (ATG) as part of the preparative regimen. A total of 12 patients died (four disease progression, six transplantation-related complications, and two others). Estimated 1-year disease-free survival (DFS) in low- and high-risk groups was 85 and 64%, respectively. We conclude that RIST can be performed safely in elderly patients with myeloid malignancies, and has therapeutic potential for those who fail conventional chemotherapy. In view of the significant association between GVHD or ATG and DFS, defined management of GVHD following RIST should become a major target of clinical research.

Adult↗

Japanese multicenter phase II and pharmacokinetic study of rituximab in relapsed or refractory patients with aggressive B-cell lymphoma.

BACKGROUND: To evaluate the efficacy and feasibility of rituximab monotherapy in Japanese patients with relapsed or refractory aggressive B-cell lymphoma. PATIENTS AND METHODS: Sixty-eight patients were treated with rituximab at 375 mg/m(2) by eight consecutive weekly infusions. Pretreatment variables affecting overall response rate (ORR) and progression-free survival (PFS) and the relationship between pharmacokinetic parameters and efficacy were analyzed. RESULTS: The ORRs of 68 enrolled patients and 57 eligible patients were 35% [95% confidence interval (CI) 24% to 48%] and 37% (95% CI 25% to 51%), respectively. Median PFS of 53 evaluable patients was 52 days, whereas time to progression of 21 eligible responders was 245 days. Mild to moderate infusion-related toxicities were observed frequently at the first infusion, but all of them were reversible. Elevated lactate dehydrogenase (LDH) and refractoriness to prior chemotherapy were unfavorable factors affecting ORR and PFS (P <0.01). Serum trough levels of rituximab and area under the concentration-time curve for responders were higher than for non-responders (P <0.05). CONCLUSIONS: Eight consecutive weekly infusions of rituximab have significant anti-lymphoma activity for relapsed or refractory aggressive B-cell lymphoma. Several pretreatment variables and serum rituximab levels are useful for predicting its efficacy.

Adult↗

High complete response rate after allogeneic hematopoietic stem cell transplantation with reduced-intensity conditioning regimens in advanced malignant lymphoma.

The possible advantage of allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a graft-versus-lymphoma effect. We explored the feasibility and efficacy of allo-HSCT with reduced-intensity (RI) regimens in advanced malignant lymphoma (ML). A total of 20 patients with indolent (n=9) or aggressive lymphoma (n=11) received allo-HSCT with an RI regimen (RIST). The preparative regimen consisted of a combination of purine analog and alkylating agent with or without antithymocyte globulin. A total of 11 patients had chemorefractory disease, seven had chemosensitive relapsed disease and two had residual disease. All of the patients received G-CSF-mobilized blood stem cells from HLA-matched siblings. Of the 20 patients, 19 achieved engraftment with acceptable regimen-related toxicities. Seven patients developed grade II-IV acute GVHD and 15 developed chronic GVHD. Of the 15 patients with evaluable disease, 12 achieved a complete response. One died of invasive fusariosis, four subsequently died of GVHD complicated with fungal infection and one died of progressive disease. With a median follow-up of 358 days, the Kaplan-Meier estimates for 1-year overall and progression-free survival were both 70%. The high response rate with low relapse observed in this study suggests that RIST may be an effective alternative curative treatment for patients with advanced ML.

Adult↗

Immune reconstitution following reduced-intensity transplantation with cladribine, busulfan, and antithymocyte globulin: serial comparison with conventional myeloablative transplantation.

The primary object of the conditioning regimen for allogeneic reduced-intensity stem cell transplantation (RIST) is immunosuppression to achieve stable engraftment of donor cells, rather than bone marrow ablation. Therefore, immune reconstitution after RIST might be different from that after conventional stem cell transplantation (CST). In this study, 22 patients underwent RIST and 28 underwent CST. The RIST regimen consisted of cladribine (2-CdA; 0.11 mg/kg/day for 6 days), BU (4 mg/kg/day for 2 days), and rabbit anti-thymocyte globulin (ATG; 2.5 mg/kg/day for 2-4 days). The CST group received either the BU (4 mg/kg/day x 4 days)/CY (60 mg/kg/day x 2 days) (n=13) or CY (60 mg/kg/day x 2 days)/TBI (4 Gy/day x 3 days) regimen (n=15). All patients underwent transplantation with G-CSF-mobilized blood stem cells. Engraftment speed after RIST was fast and seven of 22 patients did not require platelet transfusion. We noted that the numbers of CD4+, CD4+CD45RA+, and CD4+CD45RO+ T cells after transplant in the RIST group were significantly lower than those in the CST group (P=0.0001 for both the comparisons). However, the reconstitution of CD20+ B cells was faster in the RIST group (P=0.0001). The response of T cells to PHA stimulation was lower in the RIST group (P=0.0001 on day 30 and P=0.02 on day 90). Nevertheless, there were no significant differences in the incidence of bacterial, fungal, or viral infections between the two groups. We concluded that our RIST regimen might delay laboratory-evaluated T-cell immune reconstitution compared to CST; however, the observed setbacks did not directly translate into clinically significant increases in infectious episodes.

Adolescent↗

Primary cutaneous aspergillosis caused by Aspergillus ustus following reduced-intensity stem cell transplantation.

A 19-year-old woman with myelodysplastic syndrome underwent reduced-intensity stem cell transplantation [RIST: (cladribine 0.11 mg/kg for 6 days, busulfan 4 mg/kg for 2 days, and rabbit antithymocyte globulin)] from her one HLA-mismatched mother. Prophylaxis against graft-versus-host disease (GVHD) was performed with cyclosporine A (CSA) alone. Severe acute GVHD in the skin, gut, and liver developed concurrently with stable engraftment, and methylprednisolone was administered (1-2 mg/kg per day, then pulse therapy with 1 g/day for 3 days) until day 40 of transplant, when a necrotic lesion of 10 mm in diameter appeared on the right cheek. The initial skin biopsy of the affected area showed a nonspecific inflammatory change. Routine X-ray and computed tomography examinations of the sinuses, chest, and abdomen disclosed no particular abnormalities. Despite intensive antibiotic therapy, the lesion rapidly extended to form an ulcer. A second biopsy specimen obtained from the lesion showed massive septa hyphae, suggesting mold infection. Although we immediately started amphotericin B, she died of multiorgan failure on day 68. Postmortem DNA sequence analysis of the specimen using the polymerase chain reaction identified Aspergillus ustus. Although this is an extremely rare complication after transplantation, this case highlights that we should pay more attention to primary cutaneous aspergillosis in severely immunosuppressed patients.

Adult↗

Suspected delayed immune recovery against cytomegalovirus after reduced-intensity stem cell transplantation using anti-thymocyte globulin.

A reduced-intensity hematopoietic stem cell transplantation (RIST) regimen was developed to induce immunosuppression to facilitate the engraftment of donor cells. However, there have been concerns that the incidence of opportunistic infection may increase after this procedure. To address this problem, we retrospectively analyzed the medical records of 24 RIST recipients who were treated over a recent 16-month period for comparison with 31 recipients of conventional allogeneic transplantation (CST). The RIST regimen consisted of cladribine (0.66 mg/kg), busulfan (8 mg/kg), and rabbit anti-thymocyte globulin (ATG; 5-10 mg/kg). All of the patients received allogeneic peripheral blood stem cells from an HLA-identical or one-locus mismatched related donor. Although the incidence of positive CMV antigenemia was comparable between the two groups (58% vs 68%), RIST patients developed positive antigenemia significantly sooner than did CST patients (P = 0.01) and showed higher initial and maximum antigenemia values (P = 0.026 and P = 0.003, respectively). These findings may suggest that immune recovery against CMV was delayed after our RIST procedure, but this did not directly translate into an increase in clinically significant CMV disease. Early therapeutic intervention with ganciclovir might play a role in preventing the progression of early CMV infection to CMV disease.

Adolescent↗

Factors affecting toxicity, response and progression-free survival in relapsed patients with indolent B-cell lymphoma and mantle cell lymphoma treated with rituximab: a Japanese phase II study.

BACKGROUND: The aim of the study was to determine factors affecting the toxicity and efficacy of rituximab monotherapy in relapsed patients with indolent B-cell lymphoma and mantle cell lymphoma (MCL). PATIENTS AND METHODS: A total of 90 patients were enrolled and treated with rituximab infusions at 375 mg/m2 once weekly for 4 weeks. Central pathology review revealed that histologically, 81 patients had indolent B-cell lymphoma or MCL: 59 with follicular lymphoma, 17 with MCL, four with marginal zone lymphoma and one with lymphoplasmacytoid lymphoma. Of these, four were ineligible due to violation of other eligibility criteria. Pre-treatment variables affecting toxicities were analyzed for all 90 patients, and those affecting response and progression-free survival (PFS) were analyzed for 77 eligible patients with confirmed indolent B-cell lymphoma or MCL. The relationship between serum rituximab levels and efficacy was also analyzed for 66 eligible patients. RESULTS: Hematological toxicities (grade > or =3) occurred more frequently in females (P <0.05), and thrombocytopenia and leukopenia were more frequent in patients with high lactate dehydrogenase (LDH) levels (P <0.05). Non-hematological toxicities (grade > or =2) were more frequent in patients with extranodal disease or bone marrow involvement. The overall response rate (ORR) in patients receiving one prior chemotherapy regimen was higher than those receiving two or more regimens (P <0.05). The median PFS was shorter in MCL patients, in those with extranodal disease, or in those receiving two or more prior chemotherapy regimens (P <0.01). The PFS intervals of patients with higher serum rituximab levels (> or =70 microg/ml) immediately before the third infusion were longer than in other patients (P <0.01). CONCLUSIONS: Several prognostic factors and serum rituximab levels are useful for predicting the toxicity and efficacy of rituximab monotherapy.

Adult↗

Randomized phase II study of biweekly CHOP and dose-escalated CHOP with prophylactic use of lenograstim (glycosylated G-CSF) in aggressive non-Hodgkin's lymphoma: Japan Clinical Oncology Group Study 9505.

BACKGROUND: CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) is accepted as the best available standard treatment for first-line chemotherapy in aggressive non-Hodgkin's lymphoma (NHL). However, the therapeutic efficacy of CHOP remains unsatisfactory, particularly in high-intermediate risk and high risk patients, and a new strategy is warranted in this patient population. The aim of the present study was to explore a suitable therapeutic-intensified regimen for the treatment of aggressive NHL. PATIENTS AND METHODS: Between May 1995 and July 1998, a total of 70 patients with high-intermediate risk or high risk aggressive NHL, according to the International Prognostic Index, were enrolled and randomly assigned to receive either eight cycles of standard CHOP (cyclophosphamide 750 mg/m(2), doxorubicin 50 mg/m(2), vincristine 1.4 mg/m(2) and prednisolone 100 mg for 5 days) every 2 weeks, or six cycles of dose-escalated CHOP (cyclophosphamide 1500 mg/m(2), doxorubicin 70 mg/m(2), vincristine 1.4 mg/m(2) and prednisolone 100 mg for 5 days) every 3 weeks. Lenograstim (glycosylated rHuG-CSF), at a dose of 2 micro g/kg/day s.c., was administered daily from day 3 until day 13 with biweekly CHOP and until day 20 with the dose-escalated CHOP. The primary endpoint was complete response rate. RESULTS: The complete response rate was 60% [21 of 35; 95% confidence interval (CI) 42% to 76%] with biweekly CHOP and 51% (18 of 35; 95% CI 34% to 69%) with dose-escalated CHOP. The major toxicity was grade 4 neutropenia and was more frequent in the dose-escalated CHOP arm (86%) than in the biweekly CHOP arm (50%). Grade 4 thrombocytopenia was also more frequent in the dose-escalated CHOP arm (20%) than the biweekly CHOP arm (3%). Non-hematological toxicities were acceptable in both arms. One treatment-related death (due to cardiac arrhythmia) was observed in a dose-escalated CHOP patient. Progression-free survival at 3 years was 43% (95% CI 27% to 59%) in the biweekly CHOP arm and 31% (95% CI 16% to 47%) in the dose-escalated CHOP arm. Although seven patients were deemed ineligible by central review of the pathological diagnosis, the results for both eligible and all enrolled patients were similar. CONCLUSIONS: Similar complete response rates and progression-free survival rates, but lower toxicity, indicated that biweekly CHOP was superior to dose-escalated CHOP in the treatment of aggressive NHL. Based on these results, the Lymphoma Study Group of the Japan Clinical Oncology Group is conducting a randomized phase III study comparing biweekly CHOP with standard CHOP in newly diagnosed patients with advanced-stage aggressive NHL.

Adult↗

Gamma delta T-cell neoplasms: a clinicopathological study of 11 cases.

BACKGROUND: The majority of T-cell neoplasms express T-cell antigen receptor (TCR) alpha beta on their cell surface, and a few cases show the TCR gamma delta phenotype. Recently, a variety of gamma delta T-cell neoplasm was recognized; however, its clinicopathological features have not been extensively analyzed. Here we report the results of a clinicopathological study of 11 cases of gamma delta T-cell neoplasm. PATIENTS AND METHODS: During the 11-year period from 1989 to 1999, 104 patients with T-cell neoplasms were examined by flow cytometric analysis and/or immunohistochemical analysis. Tumor cells from all 104 patients expressed one or more of the T-cell antigens-CD2, CD3, CD5 and CD7. Forty-nine of the 104 cases of T-cell neoplasms were examined immunophenotypically for TCR alpha beta/gamma delta subsets. RESULTS: Expression of TCR gamma delta on tumor cells was found in five (33%) of 15 patients with precursor T-cell lymphoblastic leukemia/lymphoma, one (25%) of four with T-cell granular lymphocytic leukemia and five (26%) of 19 with peripheral T-cell lymphoma (PTCL), whereas no expression was found in 11 patients with adult T-cell leukemia-lymphoma. Primary sites of the five patients with gamma delta PTCL were as follows: lymph node, three; skin, one and liver, tonsil and skin, one. The courses of the three patients with gamma delta PTCL of nodal onset were very short (3, 5 and 9 months, respectively), and they were all resistant to combination chemotherapies. CONCLUSIONS: Although gamma delta T-cell neoplasm constitutes a heterogeneous population, it is important to examine the expression of TCR with the view to identifying possible poor prognostic subgroups, such as primary nodal gamma delta T-cell lymphoma.

Adolescent↗

Early onset Pneumocystis carinii pneumonia after allogeneic peripheral blood stem cell transplantation.

Pneumocystis carinii (P. carinii) is one of the major opportunistic pathogens responsible for hematopoietic stem cell transplantation (HSCT)-related pneumonias. Although trimethoprim-sulfamethoxazol (TMP/SMX) prophylaxis has been shown to prevent almost all P. carinii infections, 1%-2% of patients may still experience this complication. P. carinii pneumonia (PCP) is usually a late complication in patients receiving TMP/SMX prophylaxis, with most cases occurring later than 2 months post-transplant. We report a patient who developed early onset PCP after allogeneic peripheral blood stem cell transplantation (PBSCT) from an HLA-identical sibling donor. On day 12, the patient complained of dyspnea and cough. A chest X ray showed infiltrates in right upper lobe with bilateral pleural effusion. By the findings of Grocott stain on bronchoalveolar lavage fluid obtained on day 14, he was diagnosed as having PCP. Intravenous TMP/SMX failed to improve the lesion. This is the earliest onset PCP in the literature after HSCT despite the prophylactic administration of TMP/SMX before transplant.

Antibiotic Prophylaxis↗

Re-treatment of relapsed indolent B-cell lymphoma with rituximab.

The purpose of this study was to investigate the toxicity and the efficacy of re-treatment with rituximab, a chimeric mouse human anti-CD20 monoclonal antibody, in relapsed patients with indolent B-cell non-Hodgkin's lymphoma (NHL) who responded to rituximab in the previous phase I or phase II study. Thirteen patients with relapsed B-cell NHL, each of whom was confirmed to have Revised European-American Lymphoma Classification type II, 1-6 histology (indolent B-NHL), enrolled in this re-treatment study. All were re-treated with rituximab at 375 mg/m2 weekly for 4 consecutive weeks. Rituximab re-treatment was well tolerated with no grade 3/4 nonhematological toxicities, similar to that of the initial treatment. No patients developed detectable human anti-chimeric antibody. Partial responses were observed in 5 of 13 patients (38%; 95% confidence interval [CI], 14% to 68%); 6 patients showed stable disease and 2 showed progressive disease. Overall survival rate was 93% at 19 months of median follow-up after rituximab re-treatment. Median progression-free survival (PFS) after the re-treatment was 5.1 months (95% CI, 4.1 to 5.6 months), and the median PFS after the initial treatment was 8.2 months (95%CI, 5.9 to 11.3 months). Although rituximab re-treatment induced prolonged depletion of normal peripheral blood B cells in all patients, no significant decrease in serum immunoglobulin or complement level was observed. In conclusion, rituximab re-treatment was well tolerated, and it may produce a prolonged PFS in some patients with indolent B-cell NHL who showed initial response to rituximab.

Adult↗

Clinical trials of a mouse-human chimeric anti-CD20 monoclonal antibody (rituximab) for B cell non-Hodgkin's lymphoma in Japan.

Rituximab, a mouse-human chimeric anti-CD20 monoclonal antibody, induces apoptosis in B cell non-Hodgkin's lymphoma (B-NHL) cells, in addition to lysis by complement-dependent cytotoxicity and antibody-dependent cell-mediated cytotoxicity. A group of 12 patients with relapsed CD20+ B-NHL were enrolled in a phase I study; 4 received rituximab 250 mg/m2 and 8 375 mg/m2 once weekly for 4 weeks. Grade 1 or 2 infusion-related toxicity such as 'flu-like symptoms and skin reactions were observed. Of the 11 patients eligible for study enrollment, 2 achieved a complete response (CR) and 5 a partial response (PR). The T 1/2 of rituximab was 445+/-361 h, and serum rituximab levels were measurable at 3 months. Thereafter, 90 relapsed patients with indolent B-NHL or mantle cell lymphoma (MCL) were enrolled in a phase II study and received rituximab 375 mg/m2x4 weekly infusions. A central pathology review and an extramural review disclosed that 13 patients were ineligible for final analysis. Factors affecting response and progression-free survival (PFS) were analyzed in the remaining 77 patients. The overall response rate (ORR) in indolent B-NHL and MCL was 61% (37/ 61, 95% CI 47-73%) and 46% (6/13, 95% CI 19-75%), respectively. The median PFS time was 245 days in indolent B-NHL and 111 days in MCL patients. Multivariate analysis revealed that the ORR was affected by the number of prior regimens (P=0.018) and that the PFS was affected by the following three factors: disease type (P = 0.000), presence of extranodal lesions (P=0.001). and number of prior regimens (P=0.007). The PFS times of patients with higher serum rituximab concentrations at day 14 (> or =70 microg/ml) and at 3 months (> or =10 microg/ml) were significantly longer than those of patients with lower concentrations (P=0.006 and P=0.0001, respectively). In conclusion, rituximab is more effective in indolent B-NHL than in MCL. Several prognostic factors and serum rituximab concentrations are useful for predicting the therapeutic efficacy.

Adult↗