Infections in 100 cord blood transplantations: spectrum of early and late posttransplant infections in adult and pediatric patients 1996-2005

Cord blood-derived stem cells are successfully used in the treatment of cancer and congenital disorders in children. This alternative source of stem cells is also explored for adult cancer patients with limited donor options. However, delayed engraftment, prolonged neutropenia, secondary graft loss, and graft-versus-host disease (GVHD) in recipients of cord blood transplantation (CBT) make opportunistic infections a serious concern. We evaluated the spectrum of infections in adults and children undergoing CBT at our National Cancer Institute-designated comprehensive cancer center. The infection incidence rate ratio (total infection episodes/days at risk [survival after CBT] x 100) was 2.4 times higher in 35 adult patients than in 62 children, especially in adults with neutropenia (3 x higher) and GVHD (1.9 x higher). Ninety-two percent of fungal infection episodes occurred within 100 days after transplantation; half of these infections occurred in the first 30 days after CBT. Most bacterial infections (80%) were also diagnosed in the first 100 days, whereas late (>100 d) post-CBT cytomegalovirus and varicella zoster virus infections occurred only in children with chronic GVHD. Multivariate analysis showed that resolution of lymphocytopenia (> or =1000 cells/microL) (hazard ratio [HR] 0.71; p < 0.0001) and successful engraftment (HR 0.20; p < 0.0001) were associated with a low risk of serious infection. Children (HR 0.36; p < 0.0002) with sustained engraftment (HR 0.39; p < 0.004) and those with cancer in remission (HR 0.47; p < 0.007) were less likely to die from infection. More effective measures for surveillance and prevention of late cytomegalovirus and varicella zoster virus infections in children with CBT and chronic GVHD are needed.

Solvation and electronic structures of M+Ln, with M+ = Mg+ and Ca+, L = H2O, CH3OH, and NH3, and n = 1–6

The solvation clusters M+(L)n, with a singly charged alkaline earth cation Mg+ or Ca+ as the solute and with water, methanol, or ammonia as the solvent, are studied systematically in the size range n = 1–6, to compare the variations in the solvation interactions. For clusters with n ≤ 3, the energies and structural values are compared in details, with both the MP2 and B3LYP methods. For clusters with n ≥ 4, the solute–solvent and solvent–solvent interaction energies are calculated to explain the relative stability among various isomeric structures, and the contrast in both solvent and electron distribution among these cluster series. Thermal stabilities for these clusters are also examined by ab initio molecular dynamics simulations at finite temperature.Key words: solvation clusters, ab initio calculations, solute–solvent interactions, size-dependent effects.

CD133+ HCC cancer stem cells confer chemoresistance by preferential expression of the Akt/PKB survival pathway

The recent discovery of cancer stem cells (CSCs) has played a pivotal role in changing our view of carcinogenesis and chemotherapy. Based on this concept, CSCs are responsible for the formation and growth of neoplastic tissue and are naturally resistant to chemotherapy, explaining why traditional chemotherapies can initially shrink a tumor but fails to eradicate it in full, allowing eventual recurrence. Recently, we identified a CSC population in hepatocellular carcinoma (HCC) characterized by their CD133 phenotype. However, the molecular mechanism by which it escapes conventional therapies remains unknown. Here, we examined the sensitivity of these cells to chemotherapeutic agents (doxorubicin and fluorouracil) and the possible mechanistic pathway by which resistance may be regulated. Purified CD133+ HCC cells isolated from human HCC cell line and xenograft mouse models survived chemotherapy in increased proportions relative to most tumor cells which lack the CD133 phenotype; the underlying mechanism of which required the preferential expression of survival proteins involved in the Akt/PKB and Bcl-2 pathway. Treatment of CD133+ HCC cells with an AKT1 inhibitor, specific to the Akt/PKB pathway, significantly reduced the expression of the survival proteins that was normally expressed endogenously. In addition, treatment of unsorted HCC cells with both anticancer drugs in vitro significantly enriched the CD133+ subpopulation. In conclusion, our results show that CD133+ HCC cells contribute to chemoresistance through preferential activation of Akt/PKB and Bcl-2 cell survival response. Targeting of this specific survival signaling pathway in CD133+ HCC CSCs may provide a novel therapeutic model for the disease.

Infliximab for GVHD therapy in children

GVHD remains a significant complication of allogeneic hematopoietic stem cell transplantation. Tumor necrosis factor-alpha (TNF-alpha) is a major mediator of GVHD pathogenesis. Infliximab inhibits the binding of TNF-alpha with its cellular receptors and has been associated with encouraging responses in adults with severe GVHD. We retrospectively evaluated the efficacy and safety of infliximab 10 mg/kg i.v. once a week for a median of eight doses (range 1-162) in 24 children with steroid-resistant GVHD. The overall response rate in 22 evaluable children was 82% (12 CR+6 PR). Among those patients with acute GVHD, both skin and gastrointestinal involvement responded well to infliximab; however long-term outcome was poor. While infliximab may be useful to acutely control GVHD manifestations, GVHD recurs commonly upon discontinuation of infliximab. Within 100 days of the final infliximab dose, 77% of patients had bacterial infections, 32% had viral infections and 13.6% had probable or proven non-candidal invasive fungal infections. Infliximab appears to be well-tolerated and to have activity in steroid-resistant GVHD. Controlled studies to assess the pharmacokinetics and most effective dosing regimen of infliximab for the treatment of GVHD are warranted.

Breast pathology in complications associated with polyacrylamide hydrogel (PAAG) mammoplasty

OBJECTIVE

To study the tissue pathology of breast lesions associated with hydrophilic polyacrylamide gel injection augmentation mammoplasty.

DESIGN

Retrospective study.

SETTING

Private anatomical pathology practice, Hong Kong.

PATIENTS

Eight patients who underwent lumpectomy of the breast due to complications of hydrophilic polyacrylamide gel injection for augmentation mammoplasty.

MAIN OUTCOME MEASURES

Identification of hydrophilic polyacrylamide gel in breast tissue and associated pathological changes.

RESULTS

We reviewed the pathological changes in breast tissue associated with hydrophilic polyacrylamide gel injection in eight cases retrieved from our archive. Microscopically, the hydrophilic polyacrylamide gel appeared as pools of pale violet gelatinous material of variable size, between the interstices of connective tissue and fat cells. The larger pools were often surrounded by cellular reactions consisting of histiocytic cells and foreign body-type multinucleated giant cells. Inflammatory reaction featuring infiltration by lymphocytes and plasma cells in the adjacent breast tissue was observed in samples from four patients, and a sample from another patient showed acute inflammation with abscess formation. There was no evidence of abnormal cellular proliferation, atypia or malignant change in the stromal connective tissue or ductal-acinic epithelial components of the breast tissue.

CONCLUSIONS

Hydrophilic polyacrylamide gel injection for augmentation mammoplasty can give rise to a breast lump and inflammation. Pathologically, this complication is associated with fibrosis, foreign body reaction, and inflammation.

The significance of LMO2 expression in the progression of prostate cancer

LIM domain only 2 (LMO2) proteins are important regulators in determining cell fate and controlling cell growth and differentiation. This study has investigated LMO2 expression in human prostatic tissue specimens, prostate cancer cell lines, and xenografts; and has assessed the possible role and mechanism of LMO2 in prostate carcinogenesis. Immunohistochemical analysis on a tissue microarray consisting of 91 human prostate specimens, including normal, prostatic hyperplasia, high-grade prostatic intraepithelial neoplasia, and invasive carcinoma, revealed that overexpression of LMO2 was significantly associated with advanced tumour stage, as measured by Gleason score (p = 0.012), as well as with the development of distant metastasis (p = 0.018). These data were supported by quantitative real-time PCR experiments, where LMO2 mRNA levels were found to be significantly higher in prostate tumour specimen than in normal epithelium (p = 0.037). The expression of LMO2 in cell lines and xenografts representing androgen-dependent (AD) and androgen-independent (AI) prostate cancer stages was further studied. Consistent with the in vivo data, LMO2 mRNA and protein were found to be overexpressed in the more aggressive AI cells (PC3, DU145, and AI CWR22 xenografts) compared with less aggressive AD cells (LNCaP and AD CWR22 xenografts). Furthermore, stable introduction of LMO2 into LNCaP cells conferred enhanced cell motility and invasiveness in vitro, accompanied by down-regulation of E-cadherin expression. Taken together, these findings provide the first evidence to support the hypothesis that LMO2 may play an important role in prostate cancer progression, possibly via repression of E-cadherin expression.

Fludarabine allows dose reduction for total body irradiation in pediatric hematopoietic stem cell transplantation

PURPOSE

To examine, in the setting of total body irradiation (TBI) for the preparation of pediatric hematopoietic stem cell transplantation (HSCT), whether TBI dose can be reduced without compromising the efficacy of a regimen consisting of fludarabine and radiotherapy; and whether there is any increased risk of pulmonary toxicity due to the radiosensitizing effect of fludarabine.

METHODS AND MATERIALS

A total of 52 pediatric patients with hematologic malignancies received TBI-based conditioning regimens in preparation for allogeneic HSCT. Twenty-three patients received 12 Gy in 4 daily fractions in combination with cyclophosphamide, either alone or with other chemotherapeutic and biologic agents. Twenty-nine patients received 9 Gy in 3 fractions in conjunction with fludarabine and melphalan. Clinical and radiation records were reviewed to determine engraftment, pulmonary toxicity (according to Radiation Therapy Oncology Group criteria), transplant-related mortality, recurrence of primary disease, and overall survival.

RESULTS

The two groups of patients had comparable pretransplant clinical characteristics. For the 12-Gy and 9-Gy regimens, the engraftment (89% and 93%; p = 0.82), freedom from life-threatening pulmonary events (65% and 79%; p = 0.33), freedom from relapse (60% and 73%; p = 0.24), and overall survival (26% and 47%; p = 0.09) were not statistically different.

CONCLUSIONS

The addition of fludarabine and melphalan seems to allow the dose of TBI to be lowered to 9 Gy without loss of engraftment or antitumor efficacy.

Medical and non-medical barriers to outpatient treatment of fever and neutropenia in children with cancer

BACKGROUND

A number of clinical trials have employed clinical criteria that can identify pediatric patients at low-risk for complicated episodes of fever and neutropenia (F&N) and have successfully treated low-risk patients in the outpatient setting. Despite this, inpatient management remains the standard of care. This trial tested the hypothesis that a strategy of initial hospitalization followed by continuation of therapy in the outpatient setting could be practically implemented in the majority of episodes.

PROCEDURE

Patients presenting with F&N were initially evaluated to determine if they had high-risk clinical criteria that would exclude them from this approach. Eligible patients were then hospitalized and treated with iv antibiotics. On subsequent days the attending physician determined whether the patient had exhibited improvement and could continue therapy in the outpatient setting with oral antibiotics. Outpatients were seen three times weekly and continued antibiotics until recovery from F&N.

RESULTS

Outpatient oral antibiotic therapy was practically implemented in less than one-quarter of episodes of pediatric F&N. Forty-nine percent of episodes were excluded from study by medical and social protocol exclusion criteria. One hundred five episodes were enrolled and among these 59 episodes included outpatient management. Common barriers to outpatient care included serious medical comorbidities, non-medical barriers including language and distance of residence from the medical center, and lack of interest. The average duration of outpatient care was 3.6 days following an average of 3.5 days of hospitalization. Ninety percent did not require rehospitalization. They experienced no complications.

CONCLUSIONS

In only a minority of episodes can outpatient antibiotic management be implemented. Medical comorbidities and social barriers can make the transition to outpatient care difficult. However, initial hospitalization followed by oral antibiotic outpatient management appears safe and effective for low-risk patients who exhibit good responses to initial antibiotic therapy in hospital.

Clinical relevance of intra-operative sentinel lymph node examination in breast cancer management

OBJECTIVES

To determine the sensitivity, accuracy, and clinical relevance of intra-operative examination of sentinel lymph nodes in breast cancer management.

DESIGN

Retrospective study.

SETTING

Private anatomical pathology practice.

PARTICIPANTS

Three hundred breast cancer patients who underwent axillary sentinel lymph node biopsies for intra-operative assessment between January 2004 and March 2006.

MAIN OUTCOME MEASURES

Correct identification of metastatic carcinoma in sentinel lymph nodes during intra-operative examination, sparing patient a second surgery.

RESULTS

The intra-operative diagnosis of sentinel lymph node biopsies from 300 consecutive patients were compared with the final pathological diagnoses. The final pathology results showed metastatic carcinoma in 74 patients, of whom 63 (85%) were correctly diagnosed during frozen section examination. There was no false-positive case (positive predictive value 100%). The sensitivity for detecting macro- and micro-metastases were 95% and 50%, respectively (P<0.01). The sensitivity for detecting metastases in T1 and T2/above tumours were 72% and 90%, respectively (P<0.05).

CONCLUSIONS

Intra-operative examination is a reliable and sensitive method for the detection of sentinel lymph node metastasis. Eighty-five percent of the patients with metastatic disease were correctly diagnosed and spared a second operation for axillary dissection. The disadvantage of missing a positive lymph node is by far outweighed by the advantage of a single stage operation in case of a positive diagnosis. The benefit of intra-operative examination was slightly less in patients with smaller tumours.

Intensive extracorporeal photochemotherapy in pediatric patients with chronic graft-versus-host disease (cGVHD)

Extracorporeal photochemotherapy (ECP) is an alternative treatment approach in the management of chronic graft-versus-host disease (cGVHD). However, few reports have investigated the optimal treatment schedule of ECP. We treated seven pediatric patients with steroid-resistant or -dependent cGVHD with ECP. Using the Therakos UVAR XTS system, ECP was begun three (three patients) or five (four patients) times a week initially. Complete and partial responses were obtained in three patients. Three of seven patients died of GVHD-related complications. In this group initial intensive ECP did not improve the rate of response. However, this schedule appeared well tolerated.

Smoking and tuberculosis among silicotic patients

The aim of the present study was to investigate the relationship between smoking and tuberculosis (TB) among high-risk silicotic patients in Hong Kong. A cohort of 435 silicotic patients tuberculin tested from 1995-2002 was prospectively followed-up until the end of 2005. Baseline characteristics were analysed with respect to positive tuberculin reaction (> or =10 mm) at baseline and subsequent development of TB. Smoking, alcohol use and body mass index were independent predictors of positive tuberculin reaction at baseline in multiple logistic regression analysis. Total cigarette pack-yrs did not demonstrate any significant effect. The annual incidences of TB were 1,841, 2,294 and 4,181 per 100,000 for never-, ex- and current smokers, respectively. On Cox proportional hazard analysis, current smokers have a significantly higher risk of TB than other silicotic patients (adjusted hazard ratio (95% confidence interval (CI)): 1.96 (1.14-3.35)) after controlling for age, alcohol use, tuberculin status, treatment for latent TB infection and other relevant background/disease factors. A significant dose-response relationship was also observed with the daily number of cigarettes currently smoked. Smoking cessation may reduce 32.4% (95% CI: 6.5-54.0) of the risk. Smoking increases the risk of both tuberculosis infection and subsequent development of the disease among silicotic patients.

Evidence for nitrite reductase activity in intact mouse Leydig tumor cells

Nitric oxide (NO) supposedly derived via L-arginine-NO synthase (NOS) pathway has been implicated in inhibiting steroidogenesis by binding the heme moiety of steroidogenic enzymes. Previously, nitrite, and to a lesser extent nitrate ions inhibited steroidogenesis via NO by hitherto unknown reduction mechanism. Recently, a putative mammalian nitrite reductase activity ascribed to complex III of mitochondrial respiratory chain complexes (MRCC) has been reported, where MRCC inhibitors reduced NO production from nitrite variably. We thus studied the effects of MRCC inhibitors on testosterone production in mouse Leydig tumor cells (MLTC-1) without (basal) or with human chorionic gonadotropin (hCG) stimulation. In stimulated MLTC-1, MRCC inhibitors decreased testosterone production, order being: complex III (antimycin A and myxothiazol) > complex I (rotenone) > complex II (thenoyltrifluoroacetone), while cAMP production increased inversely. In unstimulated MLTC-1, MRCC inhibitors in same order, increased basal testosterone production, which correlated inversely with the percentage inhibition of NO production, with one exception; while antimycin A did not inhibit NO production in the nitrite reductase study mentioned above, it increased basal testosterone production in the present study. While MLTC-1 expressed mRNA for endothelial and neuronal, but not inducible NOS, various stimulators and inhibitors of L-arginine-NOS pathway had no effect on basal testosterone production in MLTC-1 or fresh Balb/c Leydig cells. Moreover, hCG increased nitrate uptake into MLTC-1, which suggests the gonadotropin aids nitrite and nitrate ions in their steroidogenesis inhibitory activity. In conclusion, this study supports the existence of a surrogate mammalian nitrite reductase and the dormancy of L-arginine-NOS pathway in MLTC-1.

Umbilical cord blood transplantation

Over the past decade umbilical cord blood has been established as a viable source of hematopoietic stem cells for allogeneic transplantation. Early experience with umbilical cord blood transplantation (CBT) demonstrated a lower incidence of graft-versus-host disease even though the procedure was performed with HLA-disparate grafts. The overall outcome of CBT appears similar to that of allogeneic bone marrow transplantation. The expansion of the donor selection is particularly beneficial to ethnic minorities, whose representation in the marrow registries is relatively small. The major drawbacks of CBT are slow hematopoietic recovery and a high incidence of graft failure, as a result of a lower number of progenitors infused. This paper reviews the current results of CBT and ongoing investigations to increase its availability to a larger number of recipients.

Interferon-α after autologous stem cell transplantation in pediatric patients with advanced Hodgkin's lymphoma

Thirteen children with refractory or recurrent Hodgkin's lymphoma (HL) received high-dose chemotherapy and autologous hematopoietic stem cell transplant (ASCT). After hematologic recovery, 10 patients were given interferon-alpha (IFN-alpha) as adjuvant therapy, starting at a dose of 0.5 x 10(6) U/m2 subcutaneously, three times a week. The dose was escalated as tolerated. Patients were treated for a median of 12 (4-24) months. Transient myelosuppression was the most common toxicity and led to temporary treatment interruption in five patients. The IFN-alpha dose was increased in nine patients, to a median final dose of 3.5 x 10(6) U/m2/week. With a median follow-up of 67 (range 25-114) months, nine of the 10 patients are alive and in continuous remission. One patient relapsed. Three patients were not treated with IFN-alpha initially, two because of rapidly progressive disease. One patient received IFN-alpha for treatment of relapse after transplant, and is alive in remission 10 years later. IFN-alpha has activity in children with advanced HL, and prolonged, low-dose treatment given after ASCT can be tolerated. Its therapeutic effect as a post-transplant adjuvant warrants further investigation.

Status of anti-thyroid peroxidase during normal pregnancy and in patients with hyperemesis gravidarum

Autoimmune thyroid diseases (AITD) comprising Hashimoto's thyroiditis, primary myxedema, and Graves' disease are associated with autoantibodies directed against thyroglobulin and thyroid peroxidase (anti-TPO). Anti-TPO occur in 10% of pregnant women, half of whom reportedly develop postpartum thyroid dysfunction. We recently published data on the thyroid function reference ranges in pregnant Chinese but the AITD status of our cohort was unknown. In view of this missing information we have measured anti-TPO in specimens from our cohort stored at -80 degrees C, and compared these to those of patients with hyperemesis gravidarum (HG) and nonpregnant controls. After eliminating 3 outliers from 47 nonpregnant controls, the anti-TPO concentration range was 2.2-14.7 kIU/L (n = 44). In 282 pregnant control subjects, the anti-TPO levels were less than 14.7 kIU/L (upper limit of nonpregnant controls) in 189 (67%); between 14.7-55 kIU/L in 82 (29.1%); and greater than 55 kIU/L in 11 (3.9%). The percentage of women with anti-TPO greater than 14.7 kIU/L during the first, second, and third trimesters were 47% (30/64), 39% (49/126), and 16% (15/92), respectively. Anti-TPO level was significantly higher in pregnant controls compared to nonpregnant controls and patients with HG. With reference to other studies in which anti-TPO levels greater than 60 kIU/L were considered pathologic, we conclude that more than 96% of our pregnant controls were without AITD and the data on thyroid function reference ranges we previously reported remain valid.

Differential Gene Expression Identified in Complete Hydatidiform Mole by Combining Suppression Subtractive Hybridization and cDNA Microarray

Complete hydatidiform mole (CHM) is a type of gestational trophoblastic disease with pure paternal chromosome contribution and unpredictable malignant potential. As an attempt to assess the molecular pathogenesis of CHM, suppression subtractive hybridization (SSH) combined with cDNA microarray was used to compare the gene expression pattern of CHM compared with normal first-trimester placenta of similar gestational ages. cDNA microarray analysis using tissue-specific chips constructed with subtracted cDNA libraries identified 13 differentially expressed gene transcripts. Quantitative real-time polymerase chain reaction (PCR) confirmed up-regulation of human chorionic gonadotropin beta subunit (CGB) (P=0.0008) and KIAA1200 (P=0.0005), a G-protein regulator, as well as down-regulation of osteopontin (SPP1) (P<0.0001) in 14 genotyped CHM when compared with 15 normal placentas. These candidate genes may contribute toward understanding the mechanism involved with the development and progression of CHM.

Clinical relevance of Fas expression in oesophageal squamous cell carcinoma

AIMS

To determine the extent of Fas expression in oesophageal squamous cell carcinomas (ESCCs) from Chinese patients and to correlate Fas expression with clinicopathological prognostic parameters.

METHODS

Clinicopathological data were collected from 58 patients with ESCC who underwent oesophagectomy and had no prior radiotherapy or chemotherapy. Immunostaining was performed on the primary tumours. Expression of Fas was correlated with patients' demographics, tumour characteristics and stage, R category of surgery, and patients' survival.

RESULTS

The actuarial survival rates of all patients at two and five years after surgery were 48% and 14%, respectively. Fas expression was detected in 89.7% of ESCCs. Higher Fas expression recorded on a four point scale correlated with better tumour differentiation (p < 0.01), but not with other patient or tumour variables. Importantly, higher Fas expression was associated with better survival (p = 0.0317).

CONCLUSIONS

These findings suggest that Fas activated apoptosis is important in the pathogenesis of ESCC. This molecular pathway may be a potential therapeutic target for ESCC.

Effect of all-trans retinoic acid on tissue dynamics of choriocarcinoma cell lines: an organotypic model

BACKGROUND

All-trans retinoic acid (ATRA) is a natural vitamin A derivative that has a profound effect on the regulation of cell growth, differentiation and death.

AIM

To investigate the tissue dynamic and cellular invasion effects of ATRA in choriocarcinoma (CCA), an aggressive trophoblastic tumour, by using a three-dimensional organotypic culture model system and cell invasion assay, respectively.

METHODS

An organotypic culture model of two CCA cell lines, JAR and JEG, was established. The effects of 1 microM ATRA on proliferation, differentiation and apoptosis on this CCA model were assessed by morphological assessment of the mitotic and apoptotic figures as well as by Ki-67 and caspase-related M30 cytoDeath antibody immunohistochemistry and the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL) assay. The effect of ATRA on p53 and its regulated protein product, WAF1/Cip1, was also evaluated with DO7 and p21(WAF1) antibodies, respectively. Moreover, the effect of ATRA on cellular (CCA) invasion was also investigated with Cell Invasion Kit on the JEG cell line.

RESULTS

ATRA was found to induce marked apoptosis in organotypic cultures of both cell lines, as evidenced by increased M30-positive cells (p<0.0001) and increased TUNEL-positive cells (p<0.0001) in treated cultures; to decrease proliferation, as evidenced by decreased Ki-67-positive cells (p<0.0001); and to decrease p53-DO7 immunoreactivity (p<0.0001) and increase p21(WAF1) (p<0.0001) immunoreactivity. 1.5 microM ATRA was found to effectively inhibit JEG cell invasion in the cell invasion assay.

CONCLUSION

ATRA treatment was found to inhibit invasion and proliferation and enhance apoptosis, probably by the activation of caspases and induction of differentiation. ATRA and synthetic retinoids may be alternative agents for the treatment of CCA.

Total body irradiation, fludarabine, melphalan, and allogeneic hematopoietic stem cell transplantation for advanced pediatric hematologic malignancies

We evaluated the efficacy and toxicity of adding 9 Gy of total body irradiation (TBI), in three single daily fractions of 3 Gy, to the reduced intensity regimen of fludarabine 30 mg/m2 i.v. x 4 days and melphalan 140 mg/m2 i.v. x 1 day in advanced pediatric hematologic malignancies. Twenty-two acute lymphoblastic leukemia (ALL), six acute myeloid leukemia (AML), and one non-Hodgkin lymphoma patients were transplanted. Of these, 13 were beyond second remission, and five had prior hematopoietic stem cell transplant (HSCT). Twenty-one donors were unrelated, of which 19 were from cord blood (CB) units. Three of the eight related donors were genotypically disparate. Oral mucositis and diarrhea were the most common toxicities. Twenty-seven patients achieved neutrophil engraftment (median 16 days), and 23 had platelet engraftment (median 42 days). One patient had primary graft failure. Seven patients died of non-relapse causes in the first 100 days. With a median follow-up of 52 months, seven of 22 ALL, five of six AML, and one of one lymphoma patients are alive and in remission. The regimen of TBI, fludarabine, and melphalan allows the engraftment of allogeneic hematopoietic stem cells (including mismatched CB). It was fairly well tolerated in pediatric patients, even for second transplants. Its efficacy requires further evaluation.

Extracorporeal photopheresis in children with graft-versus-host disease

Acute and chronic graft-versus-host disease (GVHD) are major complications after allogeneic hematopoietic stem cell transplantation. Systemic corticosteroid is the first line of therapy but only half of the patients will respond. The management of steroid-refractory or steroid-dependent GVHD is challenging. Intensification of immunosuppression has been the main strategy but the response rate is not satisfactory. Furthermore, the incidence of treatment-related toxicity and opportunistic infection is unacceptably high. Extracorporel photopheresis (ECP) has been used in the management of refractory GVHD. Retrospective analysis of the experience in adult patients showed activity in both acute and chronic GVHD. The procedure was well tolerated with minimal changes in the hematologic and biochemical parameters. However the machine currently approved is designed for patients over 40 kg of body weight. Significant fluid shift and venous access are major concerns when ECP is performed in children. Various modifications of the ECP procedure have been tried to manage patients with low body weight. Experience with ECP in children is limited but preliminary data also showed favorable response in children with resistant GVHD. Further investigations are needed to refine the optimal schedule, duration, and treatment technique for pediatric patients.

Cardiac manifestations of graft-versus-host disease

Graft-versus-host disease (GVHD) is a major cause of morbidity and mortality after bone marrow transplantation. Well-documented manifestations of GVHD include dermatologic, gastrointestinal, hepatic, pulmonary, musculoskeletal, and hematologic manifestations and sicca syndrome. To date, the heart has only rarely been reported to be a target of GVHD. We report a series of patients who developed bradycardia, coronary artery disease, or cardiomyolysis in association with acute or chronic GVHD. The severity of these manifestations ranged from asymptomatic to fatal. The bradycardias were responsive to increased immunosuppression. Although they are uncommon, it is important to recognize these cardiac manifestations, because they may reflect GVHD activity and may be reversible by increasing immunosuppression.