Post Autologous Bone Marrow Transplantation Research Articles

Clinical experience of using brentuximab-vedotin as therapy in relapsed/refractory Hodgkin's lymphoma at Hospital Guillermo Grant Benavente, Concepción, Chile

Hodgkin's lymphoma is a B-cell neoplasm with a good prognosis but a poor response to chemotherapy in refractory or relapsed cases. Brentuximab-vedotin is an anti-CD30 monoclonal antibody approved for use in these cases. This study aims to describe the clinical experience of patients treated with brentuximab-vedotin through expanded access modality. A retrospective study on clinical information of patients diagnosed with refractory or relapsed Hodgkin's lymphoma treated with brentuximab-vedotin at the Regional Hospital of Concepción in the period 2015-2021. 7 patients were identified, 5/7 male, with a median age of 35 years (21-50). Five cases were mixed cellularity, and two were nodular sclerosis. Four were in stage II, 1/7 in stage III, and 3/7 in stage IV. The median number of previous treatment lines was 4 (3-5), and the relapse was post-transplantation in two cases. In 6/7 cases, brentuximab-vedotin was used as induction, and in one case, it was used as post-autologous bone marrow transplant maintenance. The administration was outpatient via a peripheral route with a median dose of 150 mg and ten cycles. In one case, dose adjustment was required due to toxicity. Three out of 6 patients achieved complete remission and underwent autologous stem cell transplantation. brentuximab-vedotin is an outpatient medication with low toxicity that can optimize the treatment of patients with relapsed-refractory Hodgkin's lymphoma.

Atypical perigraft seroma masquerading as a forearm tumor in a dialysis patient.

An extremely rare manifestation of perigraft seroma (PGS), in which a dense, semisolid jelly-like mass had formed around the shunt instead of the standard fluid-like form of the usual seroma, leading to misdiagnosis with other entities, such as tumors around the synthetic arterio-venous shunt (AVS) was presented. A 64-year-old male with multiple myeloma post autologous bone marrow transplant with a renal impairment, presented with a rare form of PGS, which was noticed 2 months after placing a synthetic AVS vascular graft. The mass increased in size, and multiple attempts for excision failed due to recurrence, which led to tumor misdiagnosis. The mass reoccurrence stopped completely only after the radical shunt removal. This case report revealed a rare form of PGS, in which the seroma was represented as a firm, semisolid jelly-like mass rather than the typical fluid type transudate seroma. Despite its rarity, it was associated with a high recurrence rate because unlike the standard perishunt seroma, this semisolid jelly-like material could neither be aspirated, nor could it be resected en-bloc, leading to shunting dysfunction. Its management included advanced imaging and a high probability of shunt removal or replacement.

A179 AUTOLOGOUS BONE MARROW TRANSPLANT FOR REFRACTORY CROHN’S DISEASE: A CASE SERIES

BackgroundCrohn’s disease (CD), a form of inflammatory bowel disease (IBD) is a chronic, immune mediated condition characterized by gastrointestinal inflammation. Approximately 25% of CD patients have pharmacologically refractory disease, in which stem cell therapy has been shown to play a role.AimsA case series was performed to analyze the efficacy of autologous bone marrow transplantation (ABMT) for refractory CD in British Columbia(B.C).MethodsA chart review was conducted on patients who had undergone ABMT for treatment refractory CD between 2001 to 2021 in B.C. Demographic, clinical, laboratory and endoscopic data was collected.ResultsCase details are summarized in Table 1. 3 patients(2 female and one male) were included. All patients failed conventional therapies prior to ABMT. 2 patients underwent surgical intervention (colectomy with ileostomy) prior to ABMT. Average time from diagnosis to ABMT was 8.83 + 6.6 years. All 3 patients received standard myeloablative therapy. There were no intestinal complications post ABMT. 6 months post-ABMT transplant, all 3 patients showed significant improvement, with CDAI scores <150. Endoscopic assessment post-ABMT revealed endoscopic remission in 2 of the 3 patients. 2 of the 3 patients were in clinical remission at 12 months follow up. 1 patient relapsed and required further immunosuppressive therapy. This patient was trialed on thalidomide at 15 months post-ABMT and ultimately passed away 18 months post-ABMT from an unrelated cause. 10 years post-transplant, the remaining 2 patients remain in clinical and endoscopic remission with CDAI scores <150.ConclusionsDespite medical and surgical therapeutic advances, a subset of CD patients develop refractive disease associated with significant morbidity and mortality. In this population, there is increasing evidence in support of stem cell therapy as a treatment modality, with acute mortality less than 5% for patients with malignancy driven primarily by infectious complications and treatment-related toxicity. Clinical trials are currently underway to evaluate ABMT in CD. This case series presents the only Canadian data to date on the use of ABMT for refractory CDs and their subsequent follow up.Summary of Patient Demographics, Clinical and Disease CharacteristicsCase 1Case 2Case 3SexMFFYear of Birth198319922000Year of Diagnosis199420052011Extraintestinal Manifestations of Crohn’s DiseaseOsteoporosisArthritisArthritisPrevious Treatments5-ASA, Corticosteroids, Azathioprine, Infliximab, Adalimumab5-ASA, Corticosteroids, Methotrexate, Infliximab, AdalimumabCorticosteroids, Azathioprine, Infliximab, Visiluzumab, Adalimumab, ThalidomideSurgical HistoryTotal Colectomy and Small Bowel ResectionNoneTotal ColectomyAge at Stem Cell Therapy301814Recurrence of IBD after stem cell therapyNoNoYesFollow up after stem cell therapy8 years10 years1.5 yearsEndoscopic control after transplantation2014: EGD showed pristine mucosa, SES score of 02019: Lower GI endoscopy revealed completely normal colonic mucosa with SES score of 0.2015: Upper GI endoscopy showed mild patchy erythema involving gastric body. No ulcers. Patchy duodenitis with small aphthous ulcers. 2015: Lower GI endoscopy demonstrated patchy erosions in rectum, normal ileum and colonic mucosa.Funding AgenciesNone

Nursing Intervention for Caregivers of Post Autologous Bone Marrow Transplantation Patients at Home

Background: Autologous bone marrow transplantation is a curative procedure for hematological diseasesand immune deficiencies. The unique and intensive nature of this treatment requires distinctive care duringand post the entire transplant course. Nursing intervention for caregivers post autologous bone marrowtransplantation patients at home is an important component of the care that improves and develops knowledgeand practice of the caregivers, to take care of the patients in order to help them follow the demandingtreatment plan to reach recovery. Aim to evaluate the effect of nursing intervention for caregivers of postautologous bone marrow transplantation patients at home. Material and Method: A Quasi-experimentalstudy was carried out among convenient sample of 143 patients and their caregivers who attended the followup clinic during the first six months post autologous bone marrow transplantation. The study was conductedamong patients and their caregivers in three different hospitals Sheikh Zayed Specialized Hospital, Nationaloncology institute, and Nasser institute at outpatient’s follow-up clinics. A self-administered questionnaireof patients and their caregivers’ demographic data, and reported checklist of caregivers’ knowledge andpractices toward post-autologous bone marrow transplantation patients at home. Results: there was astatistically significant difference between pre and post nursing intervention, which indicate improvement incaregivers’ knowledge and practice post implementation of the nursing intervention program, and positivecorrelation between their knowledge and practice. Conclusion and Recommendations: Although caregivershad adequate knowledge, practice on some aspects, gaps were identified. There is a need for educationalinterventions and discharge plan to upgrade knowledge and practices of the caregivers of post autologousbone marrow transplantation patient at home.

Nursing Intervention for Caregivers of Post Autologous Bone Marrow Transplantation Patients at Home

Background: Autologous bone marrow transplantation is a curative procedure forhematological diseasesand immune deficiencies. The unique and intensive nature of this treatment requires distinctive care duringand post the entire transplant course. Nursing intervention for caregivers post autologous bone marrowtransplantation patients at home is an important component of the care that improves and develops knowledgeand practice of the caregivers, to take care of the patients in order to help them followthe demanding treatmentplan to reach recovery.Aim to evaluate the effect of nursing intervention for caregivers of post-autologous bone marrowtransplantation patients at home.Material and Method: A Quasi-experimental study was carried out among convenient sample of 143patients and their caregivers who attended the follow up clinic during the first six months post autologousbone marrow transplantation. The study was conducted among patients and their caregivers in three differenthospitals Sheikh Zayed Specialized Hospital, National oncology institute, and Nasser institute at outpatient’sfollow-up clinics.A self-administered questionnaire of patients and their caregivers’ demographic data,and reported checklist of caregivers’ knowledge and practices toward post-autologous bone marrowtransplantation patients at home.Results: There was astatistically significant difference between pre and post nursing intervention, whichindicate improvement in caregivers’ knowledge and practice post implementation of the nursing interventionprogram, and positive correlation between their knowledge and practice.Conclusion and Recommendations: Although caregivers had adequate knowledge, practice on someaspects, gaps were identified. There is a need for educational interventions and discharge plan to upgradeknowledge and practices of the caregivers of post autologous bone marrow transplantation patient at home.

A phase III study of anti-B4-blocked ricin as adjuvant therapy post-autologous bone marrow transplant: CALGB 9254

Anti-B4-blocked ricin (anti-B4-bR) is a potent immunotoxin directed against the CD19 antigen. Previous phase I and II studies suggested a possible role for anti-B4-bR as consolidation after high-dose chemotherapy and autologous stem cell transplant. Cancer and Leukemia Group B (CALGB) 9254 is a phase III study which randomized 157 patients with B-cell lymphoma in complete remission following autologous transplant to treatment with anti-B4-bR or observation. With a median follow-up time for patients of 5.8 years, the median event-free survival for protocol treatment and observation are 2.1 and 2.9 years, respectively (p = 0.275). The median overall survival for treatment and observation are 6.1 years and not reached, respectively (p = 0.063). Therefore, no differences were found in event-free survival and overall survival between protocol treatment and observation, although there was a trend toward improved survival with observation. These data fail to support a role for anti-B4-bR as consolidative therapy after bone marrow transplant in patients with B-cell lymphoma.

Post-Transplant Lymphoproliferative Disorder after Autologous Hematopoietic Cell Transplantation for Hodgkin's Lymphoma

Post-transplant lymphoproliferative disorder is a very rare complication post autologous bone marrow transplant with few cases reported so far. We report a case of a child with history of classic Hodgkin's lymphoma, nodular sclerosis type, who was treated with autologous stem cell transplantation. Three months after the transplant, he developed bilateral cervical lymphadenopathy, splenomegaly, neutropenia and thrombocytopenia. Excisional biopsy of a left cervical lymph node revealed a post-transplant lymphoproliferative disorder. The morphological pattern of this post-transplant lymphoproliferative disorder was combined monomorphic and polymorphic, with plasmacytoid/plasmablastic differentiation expressing CD20 and CD79A. Kappa and lambda light chain immunohistochemistry stains showed a clear evidence of lambda light chain restriction. Immunohistochemistry stain and in situ hybridization for Latent membrane protein-1 were positive for Epstein-Barr virus. Polymerase chain reaction study revealed monoclonal B-cell proliferation with immunoglobulin heavy chain gene rearrangement. The patient was treated with prednisolone as 2 mg/kg/day over 2 weeks with tapering over the following 3 months. The white cell count recovered with regression of splenomegaly and cervical lymphadenopathy. On his last visit to the outpatient clinic, two years after the diagnosis of post-transplant lymphoproliferative disorder, he was in good health with normal laboratory parameters.

90y-Ibritumomab Tiuxetan Treatment for Relapsed and/or Refractory B-Cell Non- Hodgkin'S Lymphoma. Multi-Institutional Argentinian Study. An Update

Background: 90Y-ibritumomab tiuxetan (Zevamab®; ZEV; Bayer-Schering Pharma- Argentina) has been approved for the treatment of relapsed, refractory and transformed (high grade) follicular lymphomas.Methods: Between Sep. 2005 and Feb. 2008, 45 patients (pts) [22 F & 23 M; median age 62 yrs (45–83)] with refractory/relapsed lymphoma were enrolled.Diagnoses: 37 follicular lymphoma (FL), 5 were mantle cell lymphoma (ML) and 3 transformed lymphoma (TL); 18 pts had bulky disease, 8 had bone marrow involvement and 21 had stage III–IV disease. Median time from diagnosis was 5 yrs (0.5– 29). Twenty two pts had received 1–2 previous treatments, and 23 pts had received 3–5 previous treatments including 5 pts with autologous bone marrow transplantation. All had previously received anti-CD20 monoclonal antibody therapy. Six pts received previous radiotherapy. ZEV was administered at 0.3 or 0.4 mCi, based on initial platelet count. Seven days before, and the same day of the ZEV administration, pts received standard rituximab 250 mg/m2. In 3 pt, ZEV was part of the conditioning regimen of autologous bone marrow transplantation.Results: Forty pts were evaluable for response: 34 (86%) pts responded – 19 CR (48%), 15 PR (38%). Overall survival and PFS for the entire group at 18 months was 63% and 37% respectively, with a median follow-up of 12 months (1–29 months). Of the 45 patients, 5 pts (11%) had died before third month and response was not assessed, 6 pts (13%) did not respond, 3 (7%) died with response from other causes, 14 pts (31%) responded and subsequently relapsed. Finally 17 pts (38%) continue to be in response, 9 (20%) lasting more than twelve months (long lasting responders). Slight differences in duration of response and survival were observed between FL vs ML and TL favouring FL (RR 2.047). Forty six per cent of pts required filgrastim for neutropenia, 24% required platelet transfusions, 22% had neutropenia plus fever and were admitted for complicated pancytopenia, and 20% required red blood cells transfusion. Two patient died 30 & 40 days after treatment with hypoplastic bone marrow complicated with sepsis in the post autologous bone marrow transplantation period. Four pts with previous bone marrow transplantation required filgrastim, transfusions and 2/3 had febrile neutropenia.Conclusion: Our experience with ZEV in relapsed and refractory FL shows 48 % CR. Even heavily treated pts that had previous bone marrow transplantation were able to receive ZEV, although they required extra support. Our experience supports the use of ZEV in relapsed and refractory lymphomas even after autologous bone marrow transplantation.

90Y-Ibritumomab Treatment for Relapsed and/or Refractory B Cell Type Non-Hodgkin's Lymphoma. Multiinstitutional Argentinian Study.

The radionucleid conjugate with monoclonal antibodies (antiCD20/90Y-ibritumomab tiuxetan) have been approved for the treatment of relapsed, refractory and transformed (high grade) follicular lymphomas. Between September 2005 and August 2007, 41 patients with refractory/relapsed lymphoma were enrolled. Median age was 62 yrs old (45–83). Twenty were women and 21 were men. Thirty three were follicular and 5 were mantle cell lymphoma and 3 transformed lymphoma. Eighteen patients had bulky disease, 8 had bone marrow involvement and 21 had stage III-IV disease. Median time from diagnosis was 5 years (0.5–29). Twenty one had received 1–2 previous treatments, and 20 pts had received 3–5 previous treatments including 5 pts with autologous bone marrow transplantation. All had previously received anti-CD20 monoclonal antibody therapy. Six pts received previous radiotherapy. 90Y-Ibritumomab (Zevamab™ Bayer-Schering Argentina) was administered at 0.3 or 0.4 mCi, based on initial platelet count. Seven days before, and on the same day of the immunoconjugate administration, pts received rituximab 250 mg/m2. Thirty eight were evaluable for response. Thirty four (89%) pts responded: 20 CR (53%) and 14 PR (36%). With a median follow-up of 10 months, 60% of pts were expected to continue in CR at 18 months. Overall survival at the same period for the entire group was 89%. Nineteen pts (46%) required filgrastim administration for neutropenia, Ten pts (24%) required platelet transfusions, 10 pts had neutropenia plus fever and they had to be admitted for complicated pancytopenia, 8 pts required red blood cells transfusion. Two patient died 30 and 40 days after treatment with hypoplastic bone marrow complicated with septicemia and in the post autologous bone marrow transplantation period, respectively. Four pts with previous bone marrow transplantation, required filgrastim, transfusions and 2/3 had febrile neutropenia. Our experience with 90Y-ibritumomab in relapsed and refractory folicullar lymphoma shows 53% CR. Even heavily treated pts, that had previous bone marrow transplantation were able to receive the radioimmunoconjugate, although they required extra support. Our experience favours the use of 90Y-Ibritumomab tiuxetan in relapsed and refractory lymphomas even if they had received previous autologous bone marrow transplantation.

Fludarabine, Idarubicin and High Dose Cytarabine (FLAG-IDA) Followed by Allogeneic Transplantation: A Successful Strategy for Remission Re-Induction in High Risk Pediatric Patients with Relapsed, Refractory and Secondary Acute Leukemias.

Despite significant advances in the treatment of childhood acute lymphoblastic (ALL) and acute myeloid (AML) leukemias, the prognosis of those with primary refractory, secondary and early relapsed disease remains extremely poor with survival reported in most studies at less than 20%. Salvage rates are particularly poor in children with ALL who relapse on therapy and in children with AML who relapse post autologous bone marrow transplant. Encouraging results using the re-induction combination regimen of Fludarabine, high dose Cytarabine and Idarubicin (FLAG-IDA) have been reported, however the majority of data is in adult patients. Here we report the largest series of pediatric patients with high risk acute leukemias receiving this regimen in combination with allogeneic hematopoietic cell transplantation as salvage therapy.Between 1999–2005 a toal of 32 patients at 2 Australian Pediatric Cancer Centers were given Fludarabine (30mg/m2 IV over 1 hour for 5 days); Idarubicin (8mg/m2 IV over 1 hour for 3 days); Cytarabine (2000mg/m2 IV over 4 hours for 5 days) and GCSF (5mcg/kg/day). There were 21 males and 11 females, with a median age of 10.4 years (range 1.7 to 15.5 years). All patients had high risk leukemias; relapsed ALL (n=13), primary refractory ALL (n=3), relapsed AML (n=13), primary refractory AML (n=1) and secondary AML (n=2). For the overall cohort median duration of first complete remission (CR1) was 16 months (range 2–34 months). Relapsed ALL patients were all considered extremely high risk with a CR1 duration of <36 months.Overall, 23 of 32 patients (71.9%) achieved a complete remission (defined as <5% blasts with evidence of marrow regeneration) following a single course of FLAG-IDA. For those with relapsed ALL, 10 of 13 patients (76.9%) achieved a remission. 2 out of the 3 patients with primary refractory ALL achieved a remission (both Philadelphia chromosome positive), 1 following a second course of FLAG-IDA. In the relapsed AML group, 9/13 (69.2%) achieved a remission, including 7 out of 10 patients who had relapsed post autologous BMT. 1 of the 2 patients with secondary AML achieved a remission. All of the 9 patients who did not achieve a remission died of progressive disease. The median time to neutrophil recovery following therapy was 26.5days (range 16–73). One patient remained aplastic and an attempt was made to transplant during this phase.22 of the 23 patients (10 AML and 12 ALL) who achieved remission proceeded to an allogeneic bone marrow transplant, following a further 2–3 courses of FLAG (without IDA) for consolidation. 70% of patients received an unrelated donor transplant. Stem cell source was MUD BM (n=9), unrelated UCB (n=6) and HLA-ID sibling donor (n=7). Overall 17 of the 22 (77.3%) remain alive and leukaemia free (9 AML and 8 ALL patients) with a median duration of 36.5 months (9–84 months). Cause of death in the transplanted patients was progressive disease (n=4) and Pneumocystis Carinii pneumonitis (n=1). In summary, for this group of high risk, early relapsed and heavily pretreated pediatiric patients, re-induction chemotherapy with FLAG-IDA followed by allogeneic transplantation has provided an excellent strategy in the achievement of long term cure.

Sustaining the graft-versus-tumor effect through posttransplant immunization with granulocyte-macrophage colony-stimulating factor (GM-CSF)–producing tumor vaccines

For many cancers, autologous bone marrow transplantation (BMT) achieves a minimal residual disease state, yet relapse rates remain high. Using a syngeneic murine bone marrow transplant model, we demonstrate that vaccination with irradiated granulocyte-macrophage colony-stimulating factor (GM-CSF)–producing autologous tumor cells is effective in the post-BMT period and actually results in a greater tumor-free survival than vaccination in the nontransplant setting. Employing T cells specific for a model tumor-antigen, we find that transplantation of the tumor-bearing host results in a massive expansion and activation of tumor-specific T cells in the early posttransplant period, but this response rapidly declines in association with tumor progression. Immunization with irradiated GM-CSF tumor cells during the period of immune reconstitution results in the sustained amplification and activation of this response that closely correlates with freedom from relapse. These results demonstrate the feasibility of integrating GM-CSF vaccines in the postautologous BMT setting and suggest mechanisms that may contribute to the observed efficacy of immunization during the critical period of immune reconstitution.

Allogeneic peripheral blood stem cell transplantation using a fludarabine-based low intensity conditioning regimen for malignant lymphoma.

Relapse is a serious complication following high-dose therapy and autologous bone marrow transplantation (ABMT) for malignant lymphoma (ML). Allogeneic transplantation (alloSCT) is a therapeutic option. However, it is associated with a high incidence of transplant-related organ toxicity and mortality. We recently reported fast engraftment and minimal transplant-related toxicity, using fludarabine-based conditioning with reduced amounts of chemotoxic drugs prior to alloSCT. We now present our experience with 23 heavily treated high risk ML patients who underwent matched alloSCT following the same low intensity conditioning. The patients (20 male, three female) were aged 13-63 years. Nineteen had NHL and four HD (resistant disease 12, partial remission 11). Five were post ABMT. Twenty-two patients had fully matched sibling donors, and one a fully matched unrelated donor. Engraftment was fast. There was no rejection or non-engraftment. Organ toxicity was moderate with no liver or renal toxicity >grade II. Four patients developed >grade II graft-versus-host disease (GVHD). Seven patients died - four of grade III-IV GVHD and severe infections, two of bacterial sepsis, one of pulmonary failure. Ten patients are alive after 22.5 (15-37) months. Survival and disease-free survival at 37 months are both 40%. Probability of relapse is 26%. These encouraging results suggest that alloSCT following fludarabine-based low intensity conditioning in high-risk patients merits further evaluation. Bone Marrow Transplantation (2000).

#506 Improved disease-free survival in children with high-risk all following autologous bone marrow transplantation (ABMT) that utilizes chemopurging post ABMT modulation of multidirug resistance (MDR) and immunochemotherapy

Houtenbos, I.; Bracho, F.; Davenport, V.; Slack, R.; de Ven, C. Van; Killen, R.; Shen, W. P.; Cairo, M.Author Information

Recommendations on the use of colony-stimulating factors in children: conclusions of a European panel.

During 1996 and 1997 a panel of European haematologists, oncologists, and neonatologists developed specific paediatric guidelines for the use of colony stimulating factors based on published literature and the clinical experience of these specialists within each of 13 countries. Well established indications for use comprise intervention in patients with life-threatening infection, adjunctive therapy post autologous bone marrow transplantation (BMT), mobilization of peripheral blood progenitor cells for autologous BMT, patients with acquired aplastic anaemia on anti-lymphocyte globulin and cyclosporin regimen, and severe congenital neutropenia. Less clear indications include primary prophylaxis to support dose intensification in children with high risk/advanced malignancies, secondary prophylaxis to prevent neutropenia in patients with a history of severe neutropenia, support therapy in cases of poor marrow function following BMT and for deteriorating marrow function following successful BMT, in neonatal sepsis and non infectious neonatal neutropenia, in drug induced neutropenia and in HIV-positive patients. Treatment is generally well tolerated and granulocyte colony stimulating factor appears better tolerated than granulocyte and macrophage colony stimulating factor. Economically colony stimulating factors have not been shown to induce excessive costs for a given patient. In general the adult guidelines are applicable to children but additional considerations (aggressive or very progressive childhood neoplasms, specific indications, neonatal use, congenital disorders) must be taken into account.

Detection of CBFbeta/MYH11 fusion transcripts in patients with inv(16) acute myeloid leukemia after allogeneic bone marrow or peripheral blood progenitor cell transplantation.

We evaluated the occurrence of the CBFbeta/MYH11 fusion transcripts by PCR analysis in 10 patients with inv(16)(p13;q22) acute myeloid leukemia (AML) who underwent allogeneic bone marrow transplantation (BMT) (n = 5), peripheral blood progenitor cell transplantation (PBPCT) (n = 3), or autologous transplantation (n = 2). In addition to the analysis of minimal residual disease (MRD), the chimerism status of patients after allogeneic transplant was studied by PCR. The CBFbeta/MYH11 fusion transcript was not detectable in six of seven patients who remained in remission after allogeneic BMT or PBPCT. Two of these patients in remission were monitored for 50 months and 64 months post-BMT. One patient in remission was PCR-positive for CBFbeta 3 months post-BMT in a single BM sample, but not in a simultaneously examined blood sample, suggesting that analyses from BM samples are more sensitive than those from blood samples. Sequential PCR assays performed 6 and 12 months post-BMT obtained from the same patient were negative. Another patient with a positive PCR assay 3 months post-allogeneic PBPCT, remained PCR positive for the CBFbeta/MYH11 fusion transcript when tested 6 months post-PBPCT. A chimerism analysis by PCR revealed a mixed chimerism status in this patient. He relapsed 7 months post-transplant. Before transplant, in all nine patients who were in complete remission of AML (eight patients in 1CR, one patient in 2CR), the CBFbeta/MYH11 transcript was detectable. In one patient in relapse, the fusion transcript was not only detectable in blood and bone marrow, but also in a cerebrospinal fluid sample prior to transplant. Two patients who received autologous BMT were monitored for CBFbeta/MYH11 transcripts 3 months after BMT. The CBFbeta/MYH11 was detected in these patients. Both patients subsequently relapsed 3 months and 23 months post-autologous BMT. The results study show that analysis of the CBFbeta/MYH11 fusion transcript by PCR seems to be a suitable method for monitoring minimal residual disease in AML patients with inv (16).

Dapsone for Pneumocystis carinii prophylaxis in children undergoing bone marrow transplantation.

Children who undergo bone marrow transplantation (BMT) are at risk for Pneumocystis carinii pneumonia (PCP). Prophylaxis using trimethoprim/sulfamethoxazole (TMP/SMX) is highly effective but the incidence of adverse drug reactions is significant. We retrospectively reviewed 33 pediatric BMT (25 allogeneic and eight autologous) in whom dapsone was used for PCP prophylaxis because patients were unable to receive TMP/SMX. Dapsone was administered at 50 mg/m2 p.o. once a week from engraftment to 180 days post-autologous BMT, and to 1 year or throughout the duration of immunosuppressive treatment post-allogeneic BMT. With a total of 7268 patient days of dapsone prophylaxis and a median follow-up of 353 days post-BMT, no proven PCP was diagnosed. Sixteen cases of chest radiograph abnormalities were noted in this patient population but none was attributed to PCP. Dapsone was well tolerated by all children with no serious adverse effects; however, one patient developed Toxoplasma gondii encephalitis during dapsone prophylaxis. Dapsone warrants further evaluation as an alternative for PCP prophylaxis in pediatric BMT patients intolerant of TMP/SMX. Additional prophylaxis should be considered for patients at high risk for T. gondii encephalitis.

CD34 progenitor cell subset analyses in normal human bone marrow and marrow harvested after intermediate-dose chemotherapy.

Previous attempts to characterize harvested marrow and peripheral blood stem cell (PBSC) in order to predict time to and quality of engraftment post autologous bone marrow transplant (autoBMT) have included use of in vitro colony forming unit (CFU) assays. These assays are hampered by interlaboratory variability and are not uniformly predictive. CD34 quantification by flow cytometric technique has also been used to assess the quality of harvested marrow and PBSC. However, a lack of standardization has hampered direct comparison of published reports. We sought to characterize these early lineage-committed CD34+ progenitor cells from non-ficolled harvested marrow with six progenitor cell (PC) panels containing CD34 antibody plus two additional early lineage markers, using multiparameter flow cytometry. The specific gating technique including simultaneous CD34-PE vs. side scatter and forward vs. side scatter, was verified using morphologic analyses of sorted CD34+ cells. An ungated file was initially acquired to assess total CD34+ content. A second file using a CD34 threshold was then acquired to resolve lineage-committed subsets. The % CD34+ cells as well as cells/microliter of bone marrow was calculated using cell counts at the time of marrow harvest. Bone marrow (mean total cell dose = 3.8 x 10(5)/kg), obtained from 42 normal donors for allogeneic transplantation was first analyzed. CD34+ cells comprised a mean 1.3% of non-ficolled marrow, with 328 CD34+ cells/microliter, and mean CD34+ cells collected was 4.8 x 10(6)/kg. While no significant differences in total cells harvested nor proportion of CD34+ cells was found, a significant decrease in CD34 cells/microliter (= 233, P = .0012) was found in cancer patients. The percentage of CD19+ and CD38+ progenitor cells was significantly increased, while CD5+ and CD71+ cells were decreased. The proportions of all other early lineage-committed CD34 subsets were not different. Measurement of lineage-committed CD34 progenitor cells is a useful technique to characterize harvested marrow and PBSC, and may be applied to predict time and quality of engraftment post ablative conditioning regimens.

Thrombocytopenia following autologous bone marrow transplantation: Evidence for autoimmune aetiology and B cell clonal involvement

Thrombocytopenia outlasting anaemia and neutropenia is a well recognised sequel of autologous bone marrow transplantation (BMT) but the pathogenesis remains unclear. Autoimmune destruction of platelets has been suggested as a possible mechanism. We studied 5 patients who had undergone autologous BMT and were found to have persistent thrombocytopenia (< 150 x 10(9)/l) 6 months from transplantation with a normal haemoglobin level and granulocyte count. Apart from a mild reduction in the megakaryocyte numbers in one case, no other quantitative or qualitative defects of the megakaryocyte lineage were present to explain the peripheral thrombocytopenia. Two cases had positive anti-platelet autoantibodies. Immunoglobulin heavy chain gene rearrangement studies of peripheral blood and bone marrow mononuclear cells using the polymerase chain reaction showed evidence of clonal rearrangement in one of the two cases with positive anti-platelet autoantibodies. Our results support the previous reports that anti-platelet antibody-mediated destruction of platelets may play a role in the pathogenesis of post-autologous BMT thrombocytopenia. Furthermore, the demonstration of a clonal B cell expansion in one of the cases with anti-platelet antibodies suggests an aetiological link between clonal B cells, autoantibody production and thrombocytopenia.

Role of interleukin-2 in human hematological malignancies.

Clinical studies with Interleukin-2 (IL-2) in human hematologic malignancies were initiated in the late 1980s. Based on clinical studies on various solid tumors, and laboratory research on hematopoietic cells, IL-2 was shown to be effective in 150 acute myeloid leukemia (AML) patients mainly for maintenance therapy in first complete remission, or with residual blast cells in the marrow. IL-2 has also been shown to be effective in remission induction in 10 patients with chronic myeloid leukemia (CML). The role of IL-2 in lymphoma patients remains to be established. IL-2 alone or in combination with Interferon-alpha, may intensify remission and prolong disease-free survival when given post autologous bone marrow transplantation (BMT) to patients with lymphoma and myeloid leukemia, and to a lesser degree, to patients with acute lymphatic leukemia (ALL). IL-2 in combination with HLA-matched or mismatched peripheral blood lymphocytes was also used post autologous BMT in preliminary studies. IL-2 was administered with or without peripheral blood lymphocytes, for prevention of relapse post T-cell-depleted allogeneic BMT in CML, ALL and AML, with encouraging results. The same strategy was shown to be effective in the reinduction of remission in patients with CML, who relapsed post BMT.

Effect of ceftazidime and gentamicin on the oropharyngeal and faecal flora of patients with haematological malignancies

Thirty-four patients with haematological malignancies were studied to investigate the effect of empirical broad-spectrum antibiotic therapy (ceftazidime and gentamicin) on the gastro-intestinal flora. Twenty-five patients with acute myeloid leukaemia or post-autologous bone-marrow transplantation were given framycetin, nystatin and colistin (Fracon), and two patients with non-Hodgkin's Lymphoma were on co-trimoxazole, as long-term gut prophylaxis. Semi-quantitative microbiology was carried out on oropharyngeal swabs and quantitative microbiology on faecal specimens. The oropharyngeal flora consisted mainly of streptococci, coagulase-negative staphylococci and coryneforms, and was little affected by ceftazidime/gentamicin. A strain of Enterobacter cloacae resistant to ceftazidime and gentamicin colonized one patient, who later developed septicaemia. The faecal flora of patients on Fracon was dominated by enterococci; the few enterobacteria present were eliminated by ceftazidime/gentamicin. The anaerobic flora was absent in 15% of patients; in the remainder, it consisted mainly of Bacteroides spp., and was little affected by ceftazidime/gentamicin. The faecal flora of patients not on Fracon always contained anaerobes, and some strains of enterobacteria persisted throughout antibiotic treatment. None of the patients was colonized by Clostridium difficile or Pseudomonas aeruginosa. Broad-spectrum therapy with ceftazidime and gentamicin appeared to have little effect on the gastro-intestinal flora, except to encourage the overgrowth of enterococci and reduce the numbers of enterobacteria.