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Biomedical subjects

M Heyman

Publications and source records attributed to M Heyman.

At least 19 recordsLinked to original sources
PubMed2006

Autologous stem cell transplantation followed by consolidation chemotherapy for patients with multiple myeloma.

Although high-dose therapy and autologous stem cell transplant (ASCT) is superior to conventional chemotherapy for treatment of myeloma, most patients relapse and the time to relapse depends upon the initial prognostic factors. The administration of non-cross-resistant chemotherapies during the post-transplant period may delay or prevent relapse. We prospectively studied the role of consolidation chemotherapy (CC) after single autologous peripheral blood stem cell transplant (auto-PBSCT) in 103 mostly newly diagnosed myeloma patients (67 patients were < or =6 months from the initial treatment). Patients received conditioning with BCNU, melphalan+/-gemcitabine and auto-PBSCT followed by two cycles of the DCEP+/-G regimen (dexamethasone, cyclophosphamide, etoposide, cisplatin+/-gemcitabine) at 3 and 9 months post-transplant and alternating with two cycles of DPP regimen (dexamethasone, cisplatin, paclitaxel) at 6 and 12 months post-transplant. With a median follow-up of 61.2 months, the median event-free survival (EFS) and overall survival (OS) are 26 and 54.1 months, respectively. The 5-year EFS and OS are 23.1 and 42.5%, respectively. Overall, 51 (49.5%) patients finished all CC, suggesting that a major limitation of this approach is an inability to deliver all planned treatments. In order to improve results following autotransplantation, novel agents or immunologic approaches should be studied in the post-transplant setting.

Adult↗
PubMed2006

Acute lymphoblastic leukemia in adolescents between 10 and 19 years of age in Denmark--secondary publication.

INTRODUCTION: Data seem to indicate that young adults with acute lymphoblastic leukemia (ALL) have a better survival when treated with pediatric protocols compared with adult ALL protocols. The purpose of the study was to report the clinical characteristics and outcome of all children and young adults 10-19 years of age diagnosed with ALL in Denmark between 1992 and 2001. MATERIAL: The study includes 99 patients 10-19 years of age with ALL in Denmark during a ten year period found in the complete NOPHO (Nordic Society of Pediatric Hematology and Oncology) registry and through the Danish Cancer Registry and local pathology databases. Data were retrieved by reviewing medical charts of the patients. A total of 61 children (10-14 years) treated on pediatric protocols and 38 young adults (15-19 years) were diagnosed with ALL. Data were reported as of January 1st 2005. RESULTS: There were no difference with respect to the distribution of T-ALL, CNS-leukemia, total white blood count and high risk chromosomal abnormalities between the two groups. There was a statistical significant lower event free survival (p<0.01) and lower overall survival (p<0.01) in young adults compared with 10-14 year-old children (0.38 vs 0.60 and 0.47 vs 0.67). There were more transplant-related deaths in the young adults. Higher treatment intensity in children may be an additional explanatory factor. Children received more prednisone, vincristine and high-dose methotrexate than young adults. CONCLUSION: Young adult patients with ALL might benefit from therapy with pediatric NOPHO ALL protocols.

Adolescent↗
PubMed2005

Children and adults with acute lymphoblastic leukaemia have similar gene expression profiles.

OBJECTIVES: To compare the gene expression pattern in children and adults with acute lymphoblastic leukaemia (ALL) in order to improve our understanding of the difference in disease biology and prognosis. METHODS: The gene expression profiles in diagnostic samples from 29 children and 15 adults with ALL were analysed using the oligonucleotide chip Hu95ver2a, produced by Affymetrix. RESULTS: Unsupervised hierarchical cluster analysis revealed that, in spite of differences in outcome, patients clustered irrespective of age, first by T-cell or B-precursor immunophenotype, and second by cytogenetic changes within the B-precursor group. The expression pattern analysis allowed the reclassification of some samples into the proper cytogenetic group. We also showed that separate clustering of samples with the BCR/ABL translocation could be explained by different breakpoint regions in the BCR. No significant difference in gene expression was observed between samples with and without CDKN2A deletion within the B-precursor group. Analysis of different age groups revealed a similarity in expression profiles when infants with the MLL translocation and adults over 40 yr of age were compared irrespective of karyotype. CONCLUSIONS: In spite of the difference in clinical outcome, the gene expression pattern in children and adults with ALL is very similar and is primarily dependent on immunophenotype and cytogenetic aberrations. However, when age groups are compared, the expression patterns of infants and adults over 40 show a remarkable similarity.

Adult↗
PubMed2004

High-dose cyclophosphamide with or without etoposide for mobilization of peripheral blood progenitor cells in patients with multiple myeloma: efficacy and toxicity.

The purpose of the study was to examine the yield of CD34(+) cells, response rates, and toxicity of high-dose cyclophosphamide with or without etoposide in patients with multiple myeloma. In total, 77 myeloma patients received either cyclophosphamide 4.5 g/m(2) (n=28) alone or with etoposide 2 g/m(2) (n=49) in a nonrandomized manner, followed by G-CSF 10 microg/kg/day for the purpose of stem cell mobilization. The effects of various factors on CD34(+) cell yield, response rate and engraftment were explored. A median of 22.39 x 10(6) CD34(+) cells/kg were collected on the first day of leukapheresis (range 0.59-114.71 x 10(6)/kg) in 71 (92%) of patients. Greater marrow plasma cell infiltration (P=0.02) or prior radiation therapy (P=0.02) adversely affected CD34(+) cell yield. In total, 45% of patients receiving cyclophosphamide and 56% of those receiving cyclophosphamide/etoposide had at least a minimum response by EBMT criteria. In all, 25% of patients who received cyclophosphamide alone vs 75.5% of patients who received combined chemotherapy required hospitalization mainly for treatment of neutropenic fever. Cyclophosphamide alone is associated with impressive CD34(+) cell yields and clear antimyeloma activity. The addition of etoposide resulted in increased toxicity without significant improvement in CD34(+) cell yield or response rates.

Adult↗
PubMed2004

Autologous stem cell transplantation followed by consolidation chemotherapy for relapsed or refractory Hodgkin's lymphoma.

Relapse remains a major cause of treatment failure after autotransplantation (auto-PBSCT) for Hodgkin's disease (HD). The administration of non-crossresistant therapies during the post-transplant period may delay or prevent relapse. We prospectively studied the role of consolidation chemotherapy (CC) after auto-PBSCT in 37 patients with relapsed or refractory HD. Patients received high-dose gemcitabine-BCNU-melphalan and auto-PBSCT followed by involved-field radiation and up to four cycles of the DCEP-G regimen, which consisted of dexamethasone, cyclophosphamide, etoposide, cisplatin, gemcitabine given at 3 and 9 months post transplant alternating with a second regimen (DPP) of dexamethasone, cisplatin, paclitaxel at 6 and 12 months post transplant. The probabilities of event-free survival (EFS) and overall survival (OS) at 2.5 years were 59% (95% CI=42-76%) and 86% (95% CI=71-99%), respectively. In all, 17 patients received 54 courses of CC and 15 were surviving event free (2.5 years, EFS=87%). There were no treatment-related deaths during or after the CC phase. Post-transplant CC is feasible and well tolerated. The impact of this approach on EFS should be evaluated in a larger, randomized study.

Adolescent↗
PubMed2004

Lactic acid bacteria secrete metabolites retaining anti-inflammatory properties after intestinal transport.

BACKGROUND: Probiotic bacteria have a beneficial effect on intestinal inflammation. In this study, we have examined the effect of lactic acid and commensal Gram positive (+) bacteria conditioned media (CM) on tumour necrosis factor alpha (TNF-alpha) release and the mechanisms involved. METHODS: Lipopolysaccharide (LPS) induced TNF-alpha secretion by peripheral blood mononuclear cells or the THP-1 cell line was monitored in the presence or absence of bacteria CM obtained from two probiotic strains, Bifidobacterium breve (Bb) and Streptococcus thermophilus (St), and three commensal bacterial strains (Bifidobacterium bifidum, Ruminococcus gnavus, and unidentified Streptococcus). Bb and St bacteria CM were allowed to cross filter grown intestinal epithelial cell monolayers (HT29-19A) to assess intestinal transport of active bacterial products. These products were characterised and their effect on LPS binding to THP-1 cells and nuclear factor kappa B (NF kappa B) activation assessed. RESULTS: Dose dependent inhibition of LPS induced TNF-alpha secretion was noted for both probiotic bacteria CM (64% and 71% inhibition for Bb and St, respectively) and to a lesser extent commensal bacteria CM (21-32% inhibition). Active products from Bb and St were resistant to digestive enzymes and had a molecular mass <3000 Da. Their inhibitory effect was preserved after transepithelial transport across intestinal cell monolayers, mainly in inflammatory conditions. LPS-FITC binding to THP-1 cells and NF kappa B activation were significantly inhibited by Bb and St CM. CONCLUSION: B breve and S thermophilus release metabolites exerting an anti-TNF-alpha effect capable of crossing the intestinal barrier. Commensal bacteria also display a TNF-alpha inhibitory capacity but to a lesser extent. These results underline the beneficial effect of commensal bacteria in intestinal homeostasis and may explain the role of some probiotic bacteria in alleviating digestive inflammation.

Bifidobacterium↗
PubMed2003

Review article: rebamipide and the digestive epithelial barrier.

Rebamipide exerts a positive effect on the digestive epithelial barrier by reinforcing its integrity in normal and in inflammatory conditions, and by normalizing the macromolecular transport across this barrier, increased by Helicobacter infection. Moreover, in mice, rebamipide is capable of diminishing allergic sensitization and of counteracting the inhibitory effect of Helicobacter pylori on oral tolerance to dietary antigens. These properties of rebamipide could explain its anti-inflammatory activity with respect to the digestive mucosa and could provide protection against allergic sensitization to foreign antigens in susceptible individuals.

Alanine↗
PubMed2003

Intestinal epithelial exosomes carry MHC class II/peptides able to inform the immune system in mice.

BACKGROUND: Intestinal epithelial cells secrete exosome-like vesicles. The aim of this study was to characterise murine intestinal epithelial exosomes and to analyse their capacity to inform the immune system in vivo in mice. METHODS: Epithelial exosomes were obtained from the murine epithelial cell line MODE K incubated in the presence or absence of interferon gamma (IFN-gamma) together with pepsin/trypsin ovalbumin hydrolysate (hOVA) to mimic luminal digestion. Exosomes isolated from MODE K conditioned media (EXO-hOVA and EXO-hOVA-IFN) were characterised by western blot, peptide mapping, and mass spectrometry. They were injected intraperitoneally to C3H/HeN mice to test their immunocompetence. RESULTS: MODE K epithelial exosomes displayed major histocompatibility complex (MHC) class I and class II (upregulated by IFN-gamma) molecules and tetraspan proteins (CD9, CD81, CD82) potentially involved in the binding to target cells. A33 antigen, an Ig-like molecule highly specific for intestinal epithelial cells, was enriched in exosomes and was also found in mice mesenteric lymph nodes, suggesting exosome migration towards the gut associated lymphoid tissues. Intraperitoneal injection of EXO-hOVA or EXO-hOVA-IFN did not induce humoral or cellular tolerance to OVA in mice. In contrast, exosomes obtained after incubation with IFN-gamma (EXO-hOVA-IFN), bearing abundant MHC class II/OVA complexes, induced a specific humoral immune response. CONCLUSIONS: Epithelial exosomes are antigen presenting vesicles bearing MHC class II/peptide complexes that prime for an immunogenic rather than tolerogenic response in the context of a systemic challenge. In the intestine, both the mucosal microenvironment and local effector cells are probably key players in determining the outcome of the immune response to exosome derived epitopes.

Animals↗
PubMed2002

Autotransplantation for advanced lymphoma and Hodgkin's disease followed by post-transplant rituxan/GM-CSF or radiotherapy and consolidation chemotherapy.

Disease relapse occurs in 50% or more of patients who are autografted for relapsed or refractory lymphoma (NHL) or Hodgkin's disease (HD). The administration of non-cross-resistant therapies during the post-transplant phase could possibly control residual disease and delay or prevent its progression. To test this approach, 55 patients with relapsed/refractory or high-risk NHL or relapsed/refractory HD were enrolled in the following protocol: stem cell mobilization: cyclophosphamide (4.5 g/m(2)) + etoposide (2.0 g/m(2)) followed by GM-CSF or G-CSF; high-dose therapy: gemcitabine (1.0 g/m(2)) on day -5, BCNU (300 mg/m(2)) + gemcitabine (1.0 g/m(2)) on day -2, melphalan (140 mg/m(2)) on day -1, blood stem cell infusion on day 0; post-transplant immunotherapy (B cell NHL): rituxan (375 mg/m(2)) weekly for 4 weeks + GM-CSF (250 microg thrice weekly) (weeks 4-8); post-transplant involved-field radiotherapy (HD): 30-40 Gy to pre-transplant areas of disease (weeks 4-8); post-transplant consolidation chemotherapy (all patients): dexamethasone (40 mg daily)/cyclophosphamide (300 mg/m(2)/day)/etoposide (30 mg/m(2)/day)/cisplatin (15 mg/m(2)/day) by continuous intravenous infusion for 4 days + gemcitabine (1.0 g/m(2), day 3) (months 3 + 9) alternating with dexamethasone/paclitaxel (135 mg/m(2))/cisplatin (75 mg/m(2)) (months 6 + 12). Of the 33 patients with B cell lymphoma, 14 had primary refractory disease (42%), 12 had relapsed disease (36%) and seven had high-risk disease in first CR (21%). For the entire group, the 2-year Kaplan-Meier event-free survival (EFS) and overall survival (OS) were 30% and 35%, respectively, while six of 33 patients (18%) died before day 100 from transplant-related complications. The rituxan/GM-CSF phase was well-tolerated by the 26 patients who were treated and led to radiographic responses in seven patients; an eighth patient with a blastic variant of mantle-cell lymphoma had clearance of marrow involvement after rituxan/GM-CSF. Of the 22 patients with relapsed/refractory HD (21 patients) or high-risk T cell lymphoblastic lymphoma (one patient), the 2-year Kaplan-Meier EFS and OS were 70% and 85%, respectively, while two of 22 patients (9%) died before day 100 from transplant-related complications. Eight patients received involved field radiation and seven had radiographic responses within the treatment fields. A total of 72 courses of post-transplant consolidation chemotherapy were administered to 26 of the 55 total patients. Transient grade 3-4 myelosuppression was common and one patient died from neutropenic sepsis, but no patients required an infusion of backup stem cells. After adjustment for known prognostic factors, the EFS for the cohort of HD patients was significantly better than the EFS for an historical cohort of HD patients autografted after BEAC (BCNU/etoposide/cytarabine/cyclophosphamide) without consolidation chemotherapy (P = 0.015). In conclusion, post-transplant consolidation therapy is feasible and well-tolerated for patients autografted for aggressive NHL and HD and may be associated with improved progression-free survival particularly for patients with HD.

Adult↗
PubMed2002

Deletion of the Ink4-locus (the p16ink4a, p14ARF and p15ink4b genes) predicts relapse in children with ALL treated according to the Nordic protocols NOPHO-86 and NOPHO-92.

Inactivation of the Ink4 gene locus locus on 9p comprising the tumour suppressor gene p16ink4a and its neighbours p14ARF and p15ink4b is common in childhood acute lymphoblastic leukaemia (ALL), but the prognostic significance is controversial. DNA from 230 patients was retrospectively analysed by Southern blotting, single strand conformation polymorphism (SSCP) and sequencing techniques. The results were correlated with clinical characteristics and outcome. One hundred and ninety-four fully analysed patients, similarly treated using the Nordic NOPHO-86 or the current NOPHO-92 protocols, were included in the outcome analysis. Deletions approached a minimally deleted region between the p16ink4a and p15ink4b genes, making the p14ARF gene the most commonly deleted coding sequence. Bi-allelic deletion was associated with high white blood cell count (WBC) (P < 0.001), T cell phenotype (P < 0.001) and mediastinal mass (P < 0.001). Patients with Ink4 locus bi-allelic deletions had an inferior pEFS (P < 0.01) and multivariate analysis indicated that bi-allelic deletion of the p16ink4a and the p14ARF genes was an independent prognostic risk factor (P < 0.05). Sub-group analysis revealed a pronounced impact of deletion status for high-risk patients, ie with high WBC. Deletion-status and clinical risk criteria (WBC) could thus be combined to further differentiate risk within the high-risk group. The analysis of the Ink4 locus adds independent prognostic information in childhood ALL treated by Nordic protocols and may help in selection of patients for alternative treatment.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Goats' milk of defective alpha(s1)-casein genotype decreases intestinal and systemic sensitization to beta-lactoglobulin in guinea pigs.

Contradictory results have been reported on the use of goats' milk in cows' milk allergy. In this study the hypothesis was tested, using a guinea pig model of cows' milk allergy, that these discrepancies could be due to the high genetic polymorphism of goats' milk proteins. Forty guinea pigs were fed over a 20 d period with pelleted diets containing one of the following: soyabean proteins (group S), cows' milk proteins (group CM), goats' milk proteins with high (group GM1) or low (group GM2) alpha(s1)-casein content. Parenteral sensitization to GM1 and GM2 proteins as also assessed. The sensitization was measured (1) by systemic IgG1 antibodies directed against bovine or caprine beta-lactoglobulin (beta-lg), alpha-lactalbumin (alpha-la) and whole caseins, and (2) by intestinal anaphylaxis measured in vitro in Ussing chambers, by the rise in short-circuit current (delta Isc) in response to milk proteins. Guinea pigs fed on CM and GM1 developed high titres (> 1500) of anti-beta-lg IgG1, with an important cross reactivity between goat and cow beta-lg. However, in guinea pigs fed on GM2, anti-goat beta-lg IgG1 antibodies were significantly decreased compared with GM1 guinea pigs (mean IgG1 titres were 546 and 2046 respectively), and the intestinal anaphylaxis was significantly decreased (3.5+/-4.5 microA/cm2) compared with that observed in GM1 guinea pigs (8.3+/-7.6 microA/cm2). Animals receiving GM1 or GM2 proteins via the parenteral route developed a marked sensitization. These results suggest that the discrepancies observed in the use of goats milk in cows' milk allergy could be due, at least in part, to the high genetic polymorphism of goats' milk proteins.

Anaphylaxis↗
PubMed2001

Alterations of epithelial permeability by Helicobacter and IL-1beta in vitro: protective effect of rebamipide.

Infection with Helicobacter increases the transcellular passage of macromolecules across the epithelium, and this effect can be prevented by a gastroprotective agent rebamipide. The aim was to gain insight into the mechanisms involved. The HT29-19A intestinal epithelial cells grown on microporous filters as monolayers were incubated in the presence or absence of rebamipide (1 or 2 mM) with: (1) suspension of a wild H. pylori strain, (2) IL-1beta (0.5 ng/ml) + IFN-gamma (2 units/ml). After incubation, the monolayers were submitted to evaluation of apoptosis by using the apoptotic cell death detection ELISA kit and to assessment of epithelial permeability in Ussing chamber where the ionic conductance (G), fluxes of mannitol (J(Man)) and of horseradish peroxidase in both intact (J(HRPi))- and degraded (J(D)) form, were measured. H. pylori increased the intact HRP fluxes across the barrier (J(HRPi) = 17 +/- 20 vs 97 +/- 70 ng/hr/cm2, P < 0.007), an effect prevented by rebamipide (J(HRPi) = 33 +/- 34 ng/hr/cm2, P < 0.006). IL-1beta increased the ionic conductance (G = 5.5 +/- 1.0 and 21.0 +/- 7.0 mS/cm2, P < 0.006), the intact HRP fluxes (J(HRPi) = 18 +/- 15 and 476 +/- 344 ng/hr/cm2, P < 0.006), and the apoptotic index of the cells (AI = 1 +/- 0 vs 3.7 +/- 0.8), all effects prevented by rebamipide (G = 12 +/- 4.9 mS/cm2, J(HRPi) = 79 +/- 38, AI = 1.6 +/- 0.6, P < 0.03 as compared to IL-beta-treated cells). In basal conditions, rebamipide increased the integrity of the barrier (G = 7.5 +/- 2.3 vs 6.0 +/- 1.8 mS/cm2 for controls, P < 0.007). In conclusion, H. pylori as well as IL-1beta, may alter epithelial permeability and rebamipide may exert its protective effect on gastric mucosa by reinforcing the epithelial barrier in normal conditions and by counteracting the deleterious effect of Helicobacter pylori and IL-1beta on macromolecular permeability.

Alanine↗
PubMed2001

In vitro drug resistance and prognostic impact of p16INK4A/P15INK4B deletions in childhood T-cell acute lymphoblastic leukaemia.

p16 gene deletions are present in about 70% of primary paediatric T-cell acute lymphoblastic leukaemia (T-ALL) and 20% of common/precursor B-cell ALL cases. It is not clear what the impact of the frequent p16 deletions is within the subgroup of T-lineage ALL. We studied the relationship between p16/p19ARF deletions, using fluorescence in situ hybridization, and in vitro drug resistance and prognosis in childhood T-ALL at diagnosis. The cellular drug resistance was measured with the methyl thiazol tetrazoliumbromide assay using a panel of drugs and the thymidylate synthase inhibition assay for methotrexate. There was a complete overlap of individual LC50 values of p16 gene homozygously deleted and p16 germ-line cases for most of the nine classes of drugs tested. The only difference was for dexamethasone: the p16-deleted group was more sensitive than the germ-line p16 group (P = 0.030). The homozygously deleted p16 T-ALL patients (n = 34) treated with the modern multiagent chemotherapy schemes of the Dutch Childhood Leukaemia Study Group ALL-VII/-VIII or Co-operative ALL-92/-97 protocols have a significantly lower 5-year disease-free survival (DFS) than germ-line p16 T-ALL (n = 25) (65.1 +/- 9.1% vs. 95.5 +/- 4.4%, Plog rank = 0.021). Hence, this study identifies a subpopulation of primary childhood T-ALL that appears to have an extremely high DFS. However, the observed differences in outcome do not seem to be related to intrinsic resistance for the tested drugs.

Adolescent↗
PubMed2001

Intestinal epithelial cells secrete exosome-like vesicles.

BACKGROUND & AIMS: Given the observations that intestinal epithelial cells (IECs) can present antigens to CD4(+) T lymphocytes and that professional antigen-presenting cells secrete exosomes (antigen-presenting vesicles), we hypothesized that IECs may secrete exosomes carrying molecules implicated in antigen presentation, which may be able to cross the basement membrane and convey immune information to noncontiguous immune cells. METHODS: Human IEC lines HT29-19A and T84-DRB1*0401/CIITA were grown on microporous filters. Release of exosomes under basal or inflammatory conditions was evaluated in conditioned apical and basolateral media after differential ultracentrifugations. Morphologic and biochemical characterization of exosomes was performed using immunoelectron microscopy, Western blotting, and matrix-assisted laser desorption ionization-time of flight mass spectrometry. RESULTS: The intestinal cell lines released 30-90-nm-diameter vesicles from the apical and basolateral sides, and this release was significantly increased in the presence of interferon gamma. MHC class I, MHC class II, CD63, CD26/dipeptidyl-peptidase IV, and A33 antigen were present in epithelial-derived exosomes. CONCLUSIONS; Human IEC lines secrete exosomes bearing accessory molecules that may be involved in antigen presentation. These data are consistent with a model in which IECs may influence antigen presentation in the mucosal or systemic immune system independent of direct cellular contact with effector cells.

Antigens, CD↗
PubMed2001

Symposium on 'dietary influences on mucosal immunity'. How dietary antigens access the mucosal immune system.

The intestinal epithelium is a selective barrier where incompletely-digested food antigens are transmitted to the immune system. Food antigens are often the starting point of intestinal diseases such as food allergy or coeliac disease. The intestinal epithelial cells (IEC) take up and process food antigens mainly by fluid-phase transcytosis involving two functional pathways, one minor direct pathway without degradation and another major lysosomal degradative pathway. Among the peptidic metabolites generated during transepithelial transport of luminal antigens, some have a molecular mass compatible with a binding to restriction (major histocompatibility complex; MHC) molecules; the latter can be up regulated on enterocytes, especially in inflammatory conditions. Indeed, interferon-gamma not only increases the paracellular absorption of antigens, but also their transcytosis across epithelial cells. It has been reported that enterocytes may even directly present peptidic epitopes to underlying T-cells. As a new potential way of transmitting peptidic information to the local or systemic immune system, the secretion by IEC of antigen-presenting vesicles called exosomes and bearing MHC-peptide complexes has recently been proposed. Many other factors such as nutritional or environmental factors can also influence the properties of the epithelial barrier and the outcome of the immune response to lumen antigens.

Animals↗
PubMed2000

Use of radiation therapy in posttransplant lymphoproliferative disorder (PTLD) after liver transplantation.

Posttransplant lymphoproliferative disorder (PTLD) is a common and life-threatening complication of immunosuppression used to prevent rejection of solid organ and bone marrow transplants. There is no standardized treatment algorithm, but numerous management strategies are available. We describe a patient who developed a solitary lymphoproliferative lesion in the porta hepatis 9 months after orthotopic liver transplant. Following reduction in immunosuppression with no response, she was treated with involved field radiotherapy utilizing CT-based treatment planning. A partial radiographic response was obtained, and she has not developed disease in the engrafted liver or systemically. Based on the present case report, involved field radiotherapy seems to be a reasonable treatment option for patients with localized PTLD. Int. J. Cancer (Radiat. Oncol. Invest.) 90:104-109, 2000.

Algorithms↗