Surgically treated patients with axial and peripheral Ewing's sarcoma family of tumours: A population based study in Finland during 1990-2009

BACKGROUND

The surgical treatment of Ewing's sarcoma family tumours (ESFTs) is challenging especially with axial tumours. The aim of the study was to analyse surgical treatment and outcome in a nationwide, population-based material consisting of surgically treated axial and peripheral ESFTs of bone and soft tissue.

METHODS

The data were collected from the Finnish National Cancer Registry and the medical records of patients diagnosed during 1990-2009. Fifty-seven patients with surgically treated ESFTs were included, 22 with an axial and 35 with a peripheral primary tumours. The surgical treatment, its complications, survival and prognostic factors were analysed.

RESULTS

Fifty-four patients underwent surgery with a curative intent and three underwent de-bulking operations. Bone reconstruction was performed in six patients with an axial and 15 with a peripheral tumour. Positive resection margins were associated with a worse five-year local relapse-free survival (33% vs. 84% for those with resection margins free of tumour cells, p = 0.003). The five-year sarcoma-specific survival was affected only by an axial location of the primary (61% vs. 89% for those with a peripheral tumour, p = 0.031). The late complications were mainly associated with bone reconstruction and more frequent among patients with a peripheral compared to an axial tumour (p = 0.031).

CONCLUSIONS

In the treatment of ESFTs, achieving adequate resection margins is crucial to avoid local relapses. Surgical complications are common particularly with bone reconstruction.

Cardiac biomarkers indicate a need for sensitive cardiac imaging among long-term childhood cancer survivors exposed to anthracyclines

AIM

The role that plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) and cardiac troponins T (cTnT) and I (cTnI) play in supplementing imaging to screen for cardiac late effects remains controversial and the impact of high-sensitivity cTnT and troponin-specific autoantibodies (cTnAAbs) remains unexplored. We studied the role of cardiac biomarkers as indicators of the late effects of anthracyclines among childhood cancer survivors.

METHODS

We measured NT-proBNP, cTnT, high-sensitivity cTnT, cTnI and cTnAAbs in 76 childhood cancer survivors at a median of 9 years after primary diagnosis. The survivors underwent conventional and real-time three-dimensional echocardiography and 62 underwent cardiac magnetic resonance imaging (MRI).

RESULTS

Of the survivors, four (5.3%) without risk factors for cardiotoxicity were cTnAAb-positive with an impaired cardiac function in MRI. Another four (5.3%) had an abnormal NT-proBNP level associated with an abnormal cardiac function and risk factors for cardiotoxicity. None showed measurable cardiac troponins, determined by the three different methods, with even the high-sensitivity cTnT-levels remaining normal.

CONCLUSION

Elevated plasma NT-proBNP or cTnAAbs indicated that childhood cancer survivors benefitted from being evaluated with modern imaging, despite normal function in conventional echocardiography. However, troponins did not seem to provide additional information on the late cardiotoxicity of anthracyclines.

Diffuse gastrointestinal bleeding and BK polyomavirus replication in a pediatric allogeneic haematopoietic stem cell transplant patient

Patients undergoing haematopoietic stem cell transplantation (HSCT) are at high risk of severe gastrointestinal bleeding caused by infections, graft versus host disease, and disturbances in haemostasis. BK polyomavirus (BKPyV) is known to cause hemorrhagic cystitis, but there is also evidence of BKV shedding in stool and its association with gastrointestinal disease. We report putative association of BKPyV replication with high plasma viral loads in a pediatric HSCT patient developing hemorrhagic cystitis and severe gastrointestinal bleeding necessitating intensive care. The observation was based on chart review and analysis of BKPyV DNA loads in plasma and urine as well as retrospective BKPyV-specific IgM and IgG measurements in weekly samples until three months post-transplant. The gastrointestinal bleeding was observed after a >100-fold increase in the plasma BKPyV loads and the start of hemorrhagic cystitis. The BKPyV-specific antibody response indicated past infection prior to transplantation, but increasing IgG titers were seen following BKPyV replication. The gastrointestinal biopsies were taken at a late stage of the episode and were no longer informative of BK polyomavirus involvement. In conclusion, gastrointestinal complications with bleeding are a significant problem after allogeneic HSCT to which viral infections including BKPyV may contribute.

Burkitt lymphoma and Ewing sarcoma in a child with Williams syndrome

Williams syndrome (WS) is a relatively rare multisystem neurodevelopmental disorder caused by a hemizygous deletion of contiguous genes on chromosome 7q11.23. Although WS does not predispose carriers to cancers, alterations of chromosome 7 are common in several human neoplasms. We report here a patient with WS and two different cancers, Burkitt lymphoma and Ewing sarcoma. Array-CGH analysis of the patient blood revealed a constitutive 1.4 million base pair deletion at 7q11.23, compatible with WS diagnosis.

Pulmonary function following allogeneic stem cell transplantation in childhood: a retrospective cohort study of 51 patients

HSCT is associated with a high risk of late morbidity. The aim of this study was to evaluate the frequency, time frame, risk factors, and possible etiology of pulmonary dysfunction following allogeneic HSCT in childhood. We evaluated the pulmonary function of 51 HSCT patients (>6 yr), by including FVC and FEV1 values prior to (baseline) and annually up to five yr after HSCT. A Cox proportional hazards model was used to analyze the risk factors for a pulmonary event. Over half (59%) of the patients developed pulmonary dysfunction, mainly consisting of restrictive abnormalities. Acute GvHD (HR 4.31, 95% CI 1.47-12.63), chronic GvHD (HR 10.20, 95% CI 2.42-43.03), and an abnormal baseline pulmonary function (HR 4.82, 95% CI 1.02-22.84) were associated with post-transplant dysfunction. FEV1 (p < 0.001) and FVC (p < 0.001) declined significantly by 12 months after HSCT and both remained below the pre-HSCT level at up to four yr post-transplantation. HSCT in childhood is associated with early and persistent restrictive impairment of pulmonary function. Patients with extensive chronic GvHD are particularly vulnerable to severe pulmonary dysfunction. Scheduled pulmonary function testing is warranted as part of the follow-up of survivors of HSCT in childhood.

Three-dimensional echocardiography and cardiac magnetic resonance imaging in the screening of long-term survivors of childhood cancer after cardiotoxic therapy

The left ventricular (LV) volumes, ejection fraction (EF), and dyssynchrony indexes for the 16 and 12 cardiac segments (Tmsv16-SD and Tmsv12-SD, respectively) were analyzed among nonadult, anthracycline-exposed long-term survivors of childhood cancer and compared with those of healthy controls using conventional and real-time 3-dimensional echocardiography (RT-3DE) with cardiac magnetic resonance (CMR) imaging in a prospective, cross-sectional, single tertiary center setting. Seventy-one survivors and gender-, body surface area-, and age-matched healthy controls were studied by conventional echocardiography and RT-3DE. Fifty-eight of the 71 survivors underwent also CMR. The survivors were evaluated in 2 groups. Group I consisted of 63 exposed to anthracyclines and group II consisted of 8 also exposed to cardiac irradiation. By RT-3DE, the group I survivors had a lower LVEF (57% vs 60%, respectively, p = 0.003) and larger body surface area-indexed LV end-systolic volume (31 vs 28 ml/m(2), respectively, p = 0.001) than controls. The Tmsv16-SD was higher in group II than in I (1.93% vs 1.39%, respectively, p = 0.003). None of the survivors had an abnormal fractional shortening (<28%), but 10% had an LVEF <50% by RT-3DE. An LVEF <55% was detected in 45 of 58 (78%) of those imaged with CMR. In conclusion, RT-3DE seems to detect more abnormalities in cardiac function than conventional echocardiography following childhood cancer therapy. The LV dyssynchrony indexes derived from RT-3DE appear potentially useful in assessing the early signs of cardiotoxicity between anthracycline and cardiac irradiation exposed long-term survivors of childhood cancer.

[Childhood and adolescent cancer was cured--how to support health in adulthood?]

The number of long-term survivors after cancer therapy in childhood and young adulthood is increasing. Accordingly, life-long follow-up of significant health problems related to the given cancer therapy is needed as only one third of the survivors will remain free of any physical or psychosocial late effects. At present, national activity is needed to establish a uniform follow-up clinic service to support education, diagnostics, therapy and rehabilitation of these long-term adverse effects after cancer therapy at young age.

[Solid tumors in children]

A quarter of cancers diagnosed in those under 18 years of age are leukemias, another quarter being tumors of the central nervous system. The remaining cancers are solid tumors occurring elswehere in the body, most commonly lymphomas, soft tissue and bone sarcomas, neuroblastomas and Wilms tumors. In almost all cases, the treatment of these solid tumors consists of combinations of surgery, cytotoxic drugs and radiotherapy. Although the prognoses have improved, they exhibit variation even within tumor groups. New targeted therapies are being developed, but for the time being they do not have any significant role.

Incidence of Severe Osteonecrosis Requiring Total Joint Arthroplasty in Children and Young Adults Treated for Leukemia or Lymphoma: A Nationwide, Register-Based Study in Finland and Denmark

Purpose: The population-based incidence of severe osteonecrosis (ON) necessitating total joint arthroplasty (TJA) in patients with hematological cancer is unknown. This study assessed the incidence of ON requiring primary TJA in children and young adults treated for leukemia or lymphoma. Methods: Patients diagnosed with leukemia or lymphoma before 31 years of age were identified from the Finnish and Danish Cancer Registries. These data were combined with those from the National Hospital Discharge and the Finnish Arthroplasty Registers. Data on the orthopedic procedures performed and the appropriate diagnosis codes given before the age of 40 were also retrieved. Results: The estimated cumulative incidence of TJA was 4.5% at 20 years for patients treated for chronic myeloid leukemia, followed by 2.1% for patients treated for acute myeloid leukemia. It was considerably lower in patients with acute lymphoblastic leukemia (ALL; 0.4%). Multivariate analysis revealed that allogeneic stem cell transplantation (allo-SCT) increased the risk of TJA (hazard ratio [HR]=9.4; 95% CI: 5.3-16.9). The risk of TJA was higher in patients diagnosed with cancer at 10-19 and 20-30 years of age than in those diagnosed before the age of 10 (HR=24; 95% CI: 3.1-176 and HR=26; 95% CI: 3.6-192 respectively). Conclusion: The incidence of ON requiring TJA was highest among patients with myeloid leukemias and lowest in patients treated for ALL. Allo-SCT and age ≥10 years at diagnosis were the most important risk factors for ON requiring TJA in hematological malignancies.

Limited impact of EU paediatric regulation on Finnish clinical trials highlights need for Nordic collaboration

The Finnish Investigators Network for Paediatric Medicines (FINPEDMED) was established in 2007, to meet the expected increase in paediatric clinical trials following the new EU Paediatric Regulation. Between 2007 and 2012, FINPEDMED received 91 trial requests, 18 trials were started, and in 24 cases, Finnish investigators were not selected by sponsors.

CONCLUSION

This experience from Finland highlights the need for Nordic collaboration to increase expertise, recruitment base and attractiveness for sponsors.

High prevalence of sacrococcygeal teratoma in Finland - a nationwide population-based study

AIM

The birth prevalence of sacrococcygeal teratoma (SCT) has been reported to range from 1:27 000 to 1:40 000. We assessed the population-based prevalence and clinical presentation of SCT over 22 years.

METHODS

We identified all cases of SCT, including live births, stillbirths and terminations of pregnancy (TOPs), in the Finnish Register of Congenital Malformations, covering 1987-2008. Data on prenatal diagnoses, pregnancy outcomes, infant deaths and associated anomalies were collected.

RESULTS

One hundred and twenty four SCT cases were identified among 1 331 699 pregnancies. There were 89 (72%) live births, 13 (10%) stillbirths and 22 (18%) TOPs. The total prevalence of SCT was 1:10 700. Tumours were detected in utero in 55% of the pregnancies with SCT. The proportion of perinatal deaths among all SCT births was 28%. Thirty percentage of the cases had associated abnormalities (mainly of the urinary tract and various syndromes).

CONCLUSION

This nationwide, population-based study on SCT shows that the total and birth prevalence of SCT in Finland is markedly higher than previously reported. This may reflect true differences between populations, but may also be explained by accurate nationwide registration of SCTs. The high perinatal mortality rate has an impact on counselling of families and planning of deliveries.

Ewing's sarcoma family of tumors in Finland during 1990-2009: a population-based study

BACKGROUND

Ewing's sarcoma family of tumors (ESFTs) are rare bone and soft tissue tumors characterized by specific genetic alterations. Our aim was to carry out a nationwide analysis of ESFT, to survey the treatments used and to report the five-year disease specific and event-free survival rates (EFS and DSS).

MATERIAL AND METHODS

The study data was gathered from the Finnish National Cancer Registry and all five University Hospitals and consisted of 76 bone and soft tissue ESFT patients diagnosed during 1990-2009. Their medical records were reviewed and data on their disease, treatments, complications and outcome were analyzed.

RESULTS

The five-year EFS and DSS of patients with localized disease at diagnosis (n = 57) were 70% and 60%, respectively. Factors contributing to DSS and EFS were the axial vs. peripheral site of primary tumor and adequate surgical resection of the primary tumor. DSS was also affected by patient's age at diagnosis and the treatment employed. The five-year DSS of patients with metastatic disease at diagnosis (n = 19) was 33% and both preoperative and high dose chemotherapy were associated with improved survival.

CONCLUSION

Population-based studies including both bone and soft tissue ESFTs are few. In this nationwide, population-based study on Finnish bone and soft tissue ESFT patients, we find their treatment successful and results comparable to those previously published. Absence of metastases, young age at diagnosis and a peripheral primary tumor site were associated with a better prognosis. It seems that surgical resection of the primary tumor should be performed whenever adequate resection margins can be achieved. The role of high dose chemotherapy merits further studies in this setting.

[Childhood brain tumors]

Brain tumors are the second most common pediatric neoplastic disease after leukemias. As causes of mortality and morbidity they add up to the most significant group of tumors. Treatment is based on thorough surgical excision of the tumor. Additional treatment with cytotoxic agents and radiotherapy is applied to malignant tumors. Treatment results have improved so that approximately three children out of four will make complete recovery from brain tumor. Long-term problems are, however, common and often significantly weakening the quality of life.

[Childhood leukemia]

Most cases of childhood leukemia are acute lymphoblastic leukemia, a small proportion being myelogenous leukemia. Chronic myelogenous leukemia is rare in children, whereas chronic lymphocytic leukemia is not encountered. The prognosis of childhood leukemia has improved considerably so that approximately 80 to 90% of those having lymphocytic leukemia and 60 to 70% of those having myelogenous leukemia will recover fully. The challenge is to develop new treatments for disease groups having a poor prognosis and on the other hand to lighten the treatments for leukemias having a good prognosis.

[Immune deficiency and infections in children having cancer]

Childhood cancer and its treatment weaken the immune defenses and predispose the patient to infections. The recovery of immune defences depends on the provided cancer therapy and associated complications such as the graft-versus-host reaction. Recovery takes place gradually and the spectrum of infections suffered by the patient reflects the different stages of restoration of the immune defenses. Bacterial and fungal infections dominate the early, neutropenic phase, viral infections being predominant during the later lymphocytopenic phase. In the follow-up it is essential to recognize the risk factors, to observe the recuperation of the immune system and to treat the complications.

Immunity after (re)vaccination of paediatric patients following haematopoietic stem cell transplantation

AIMS

Loss of specific immunity follows allogeneic haematopoietic stem cell transplantation (HSCT) in the majority of cases. Responses to (re)vaccinations can be used as indicators of a functional immunological recovery.

METHODS

Twenty-three paediatric recipients of HSCT were enrolled in a single centre setting and responses to scheduled immunizations analysed.

RESULTS

Immunity to vaccine-preventable diseases was impaired post HSCT, but (re)vaccinations induced protective responses in 59-100%, depending on the vaccine, regardless of prior graft-versus-host disease (GVHD) history.

CONCLUSION

Despite the marked impact of moderate to severe chronic prior GVHD on both the qualitative and quantitative T-cell recovery post allogenic HSCT, most paediatric recipients of allogeneic stem cell grafts appear to attain protective antibody levels after immunization.

The use of plerixafor in harvesting autologous stem cells in the pediatric setting

The mobilization of stem cells using the standard approach, chemotherapy and G-CSF, may not be successful in all cases heavily pretreated. Plerixafor (AMD3100) has emerged as a viable option in attempts to mobilize stem cells among these patients. The use of plerixafor in the adult setting has been established, but data on pediatric use is scarce. We report on the use of plerixafor in eight pediatric cases either as add-on to chemotherapy plus G-CSF or in remobilization.

[Outcome of childhood cancer in Tampere, Finland]

BACKGROUND

We investigated the outcome of childhood cancer within the Tampere University Hospital area, Finland.

PATIENTS AND METHODS

We collected the data from 291 patients, who were 0 to 16 years of age at the time of cancer diagnosis in 1997 to 2006. The largest diagnosis groups were leukemias, malignant tumors of the central nervous system, and lymphomas.

RESULTS

Altogether 83% of the patients were alive and at least under long-term remission at the time of the study.

CONCLUSIONS

Outcome of childhood cancer in Tampere University Hospital area is in line with international results.

Individualized toxicity-titrated 6-mercaptopurine increments during high-dose methotrexate consolidation treatment of lower risk childhood acute lymphoblastic leukaemia. A Nordic Society of Paediatric Haematology and Oncology (NOPHO) pilot study

This study explored the feasibility and toxicity of individualized toxicity-titrated 6-mercaptopurine (6MP) dose increments during post-remission treatment with High-dose methotrexate (HDM) (5000 mg/m(2), ×3) in 38 patients with Childhood (ALL). Patients were increased in steps of 25 mg 6MP/m(2) per day if they did not develop myelotoxicity within 2 weeks after HDM. 6MP could be increased in 31 patients (81%). Toxicity was acceptable and did not differ significantly between groups. Patients receiving 75 mg/m(2) per day had significantly shorter duration of treatment interruptions of 6MP than the remaining patients (P = 0·03). This study shows individualized toxicity-titrated 6MP dosing during consolidation is feasible without increased risk of toxicity.

Interphase fluorescent in situ hybridization deletion analysis of the 9p21 region and prognosis in childhood acute lymphoblastic leukaemia (ALL): results from a prospective analysis of 519 Nordic patients treated according to the NOPHO-ALL 2000 protocol

Interphase fluorescent in situ hybridization (FISH) was applied on diagnostic BM smears from 519 children with acute lymphoblastic leukaemia (ALL) in order to establish the frequency and prognostic importance of 9p21 deletion in children enrolled in the Nordic Society of Paediatric Haematology and Oncology (NOPHO) - 2000 treatment protocol. Among the patients, 452 were diagnosed with B-cell precursor (BCP)-ALL and 66 with T-ALL. A higher incidence of 9p21 deletions was found in T-ALL (38%) compared to BCP-ALL (15·7%). Homozygous deletions were found in 19·7% of T-ALL and 4·0% of BCP-ALL; hemizygous deletions were found in 18·2% and 11·7% respectively. In our series, 9p21 deletions were detected in all age groups with a steady rise in the frequency with age. There was no significant difference in outcome between cases with or without 9p21 deletion or between cases with hemi- or homozygous deletions of 9p21. In conclusion, in this large series of childhood ALL deletion of 9p21 was not associated with worse prognosis. However, interphase FISH deletion analysis of 9p21 could be used as a first step to detect unfavourable subtle cytogenetic aberrations such as the dic(9;20) rearrangement.

[Leucopenia in children]

Decreased leukocyte values in children are usually due to the decrease in the number of neutrophilic granulocytes. This is usually a transient phenomenon associated with viral infections. In infancy and early childhood, immune mediated neutropenias are possible causes of prolonged leukopenia. Causes of rare leukopenias are numerous, including underlying diseases such as congenital myelopathy, a syndrome or malignant hematological disease. The risk of infection associated with neutropenia is increased especially in patients with a production defect of the bone marrow as the underlying cause.

A high circulating copy number of HHV-6 due to chromosomal integration in a child with acute lymphoblastic leukemia

We report a case of a 3.5-year-old female with a very high copy number of human herpesvirus 6 (HHV-6) detected by PCR in blood during acute lymphoblastic leukemia induction therapy. The patient was unsuccessfully treated with antiviral drugs. HHV-6 genome was shown to be constitutively integrated into chromosome 22q-tel, likely to be inherited from the mother who was found to carry high HHV-6 copy number. This case highlights the importance of excluding HHV-6 chromosomal integration before diagnosing HHV-6 infection or reactivation in immunocompromised patients.

Clinical outcome of children with newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia treated between 1995 and 2005

PURPOSE

In a previous analysis of 326 children with Philadelphia chromosome (Ph) -positive acute lymphoblastic leukemia (ALL) treated between 1986 and 1996, hematopoietic stem-cell transplantation from HLA-matched related donors, but not from unrelated donors, offered a superior outcome than chemotherapy alone. To evaluate the impact of recent improvements in chemotherapy and transplantation, we performed a similar analysis on patients treated in the following decade.

PATIENTS AND METHODS

We analyzed 610 patients with Ph-positive ALL treated between 1995 and 2005 without tyrosine kinase inhibitor therapy. The median follow-up duration was 6.3 years.

RESULTS

Complete remission was achieved in 89% of patients. The 7-year event-free survival and overall survival rates were superior in the present cohort compared with the previous cohort (32.0% ± 2.0% v 25.0% ± 3.0, respectively, P = .007; and 44.9% ± 2.2% v 36.0% ± 3.0%, respectively, P = .017). Compared with chemotherapy alone, transplantation with matched related donors or unrelated donors in first remission (325 patients) showed an advantage with increasing follow-up, suggesting greater protection against late relapses (hazard ratio at 5 years, 0.37; P < .001). In the multivariate Cox regression analysis accounting for treatment (transplantation v no transplantation), age, leukocyte count, and early response had independent impact on treatment outcome.

CONCLUSION

Clinical outcome of children and adolescents with Ph-positive ALL has improved with advances in transplantation and chemotherapy. Transplantations with matched related donors and unrelated donors were equivalent and offered better disease control compared with chemotherapy alone. Age, leukocyte count, and early treatment response were independent prognostic indicators. The results of this study will serve as a historical reference to evaluate the therapeutic impact of tyrosine kinase inhibitors on the outcome of Ph-positive ALL.

Molecular and clinical heterogeneity in CLCN7-dependent osteopetrosis: report of 20 novel mutations

The "Osteopetroses" are genetic diseases whose clinical picture is caused by a defect in bone resorption by osteoclasts. Three main forms can be distinguished on the basis of severity, age of onset and means of inheritance: the dominant benign, the intermediate and the recessive severe form. While several genes have been involved in the pathogenesis of the different types of osteopetroses, the CLCN7 gene has drawn the attention of many researchers, as mutations within this gene are associated with very different phenotypes. We report here the characterization of 25 unpublished patients which has resulted in the identification of 20 novel mutations, including 11 missense mutations, 6 causing premature termination, 1 small deletion and 2 putative splice site defects. Careful analysis of clinical and molecular data led us to several conclusions. First, intermediate osteopetrosis is not homogeneous, since it can comprise both severe dominant forms with an early onset and recessive ones without central nervous system involvement. Second, the appropriateness of haematopoietic stem cell transplantation in CLCN7-dependent ARO patients has to be carefully evaluated and exhaustive CNS examination is strongly suggested, as transplantation can almost completely cure the disease in situations where no primary neurological symptoms are present. Finally, the analysis of this largest cohort of CLCN7-dependent ARO patients together with some ADO II families allowed us to draw preliminary genotype-phenotype correlations suggesting that haploinsufficiency is not the mechanism causing ADO II. The availability of biochemical assays to characterize ClC-7 function will help to confirm this hypothesis.

The degree of myelosuppression during maintenance therapy of adolescents with B-lineage intermediate risk acute lymphoblastic leukemia predicts risk of relapse

Drug doses, blood levels of drug metabolites and myelotoxicity during 6-mercaptopurine/methotrexate (MTX) maintenance therapy were registered for 59 adolescents (>or=10 years) and 176 non-adolescents (<10 years) with B-cell precursor acute lymphoblastic leukemia (ALL) and a white blood cell count (WBC) <50 x 10(9)/l at diagnosis. Event-free survival was lower for adolescents than non-adolescents (pEFS(12y):0.71 vs 0.83, P=0.04). For adolescents staying in remission, the mean WBC during maintenance therapy (mWBC) was related to age (r(S)=0.36, P=0.02), which became nonsignificant for those who relapsed (r(S)=0.05, P=0.9). The best-fit multivariate Cox regression model to predict risk of relapse included mWBC and thiopurine methyltransferase activity, which methylates mercaptopurine and reduces the intracellular availability of cytotoxic 6-thioguanine nucleotides (coefficient: 0.11, P=0.02). The correlation of mWBC to the risk of relapse was more pronounced for adolescents (coefficient=0.65, P=0.003) than for non-adolescents (coefficient=0.42, P=0.04). Adolescents had higher mean neutrophil counts (P=0.002) than non-adolescents, but received nonsignificantly lower mercaptopurine and MTX doses during maintenance therapy. Red blood cell MTX levels were significantly related to the dose of MTX among adolescents who stayed in remission (r(S)=0.38, P=0.02), which was not the case for those who developed a relapse (r(S)=0.15, P=0.60). Thus, compliance to maintenance therapy may influence the risk of relapse for adolescents with ALL.

Acute lymphoblastic leukemias with normal karyotypes are not without genomic aberrations

Current cytogenetic techniques have enabled more accurate definition of genetic aberrations in the lymphoblasts of patients with acute lymphoblastic leukemia (ALL), at least in most cases. Detecting the cryptic aberrations undetected by conventional cytogenetic methods is important for disease classification, evaluation of prognosis, and minimal residual disease follow-up. We have studied DNA copy number alterations of 27 adolescent ALL patients with normal (n=26) or failed (n=1) karyotype at diagnosis using microarray comparative genomic hybridization (CGH). Aberrations were detected in 85% of cases, deletions being more frequent (39 in 19 patients) than gains (14 in 10 patients). Deletions of 9p21.3 were the most common aberration, and 41% of deletions were cryptic and <5 Mb in size. We conclude that ALL without any form of genetic alteration probably does not exist. Microarray CGH is a powerful tool to reveal otherwise cryptic aberrations in adolescent ALL.

Methotrexate/6-mercaptopurine maintenance therapy influences the risk of a second malignant neoplasm after childhood acute lymphoblastic leukemia: results from the NOPHO ALL-92 study

Among 1614 children with acute lymphoblastic leukemia (ALL) treated with the Nordic Society for Paediatric Haematology and Oncology (NOPHO) ALL-92 protocol, 20 patients developed a second malignant neoplasm (SMN) with a cumulative risk of 1.6% at 12 years from the diagnosis of ALL. Nine of the 16 acute myeloid leukemias or myelodysplastic syndromes had monosomy 7 (n = 7) or 7q deletions (n = 2). In Cox multivariate analysis, longer duration of oral 6-mercaptopurine (6MP)/methotrexate (MTX) maintenance therapy (P = .02; longest for standard-risk patients) and presence of high hyperdiploidy (P = .07) were related to increased risk of SMN. Thiopurine methyltransferase (TPMT) methylates 6MP and its metabolites, and thus reduces cellular levels of cytotoxic 6-thioguanine nucleotides. Of 524 patients who had erythrocyte TPMT activity measured, the median TPMT activity in 9 patients developing an SMN was significantly lower than in the 515 that did not develop an SMN (median, 12.1 vs 18.1 IU/mL; P = .02). Among 427 TPMT wild-type patients for whom the 6MP dose was registered, those who developed SMN received higher average 6MP doses than the remaining patients (69.7 vs 60.4 mg/m2; P = .03). This study indicates that the duration and intensity of 6MP/MTX maintenance therapy of childhood ALL may influence the risk of SMNs in childhood ALL.

Thiopurine methyltransferase activity is related to the risk of relapse of childhood acute lymphoblastic leukemia: results from the NOPHO ALL-92 study

Myelotoxicity during thiopurine therapy is enhanced in patients, who because of single nucleotide polymorphisms have decreased activity of the enzyme thiopurine methyltransferase (TPMT) and thus more thiopurine converted into 6-thioguanine nucleotides. Of 601 children with acute lymphoblastic leukemia (ALL) who were treated by the NOPHO ALL-92 protocol, 117 had TPMT genotype determined, whereas for 484 patients only erythrocyte TPMT activity was available. The latter were classified as heterozygous, if TPMT activity was <14 IU/ml, or deficient (<1.0 IU/ml). 526 patients had TPMT wild type, 73 were presumed heterozygous, and two were TPMT deficient. Risk of relapse was higher for the 526 TPMT wild type patients than for the remaining 75 patients (18 vs 7%, P=0.03). In Cox multivariate regression analysis, sex (male worse; P=0.06), age (higher age worse, P=0.02), and TPMT activity (wild type worse; P=0.02) were related to risk of relapse. Despite a lower probability of relapse, patients in the low TPMT activity group did not have superior survival (P=0.82), possibly because of an excess of secondary cancers among these 75 patients (P=0.07). These data suggest that children with ALL and TPMT wild type might have their cure rate improved, if the pharmacokinetics/-dynamics of TPMT low-activity patients could be mimicked without a concurrent excessive risk of second cancers.

Acute lymphoblastic leukemia in adolescents and young adults in Finland

BACKGROUND

Interest has recently been paid to adolescents and young adults with acute lymphoblastic leukemia, particularly because all reports so far published indicate that these patients have a better outcome when treated with pediatric rather than adult therapeutic protocols. There are different biological subtypes of acute lymphoblastic leukemia with distinct features and prognoses; the distribution of these subtypes is not well known among adolescents. We, therefore, studied acute lymphoblastic leukemia in adolescents and young adults aged 10 to 25 years in Finland.

DESIGN AND METHODS

This population-based study included 225 consecutive patients aged 10-25 years diagnosed with acute lymphoblastic leukemia during 1990-2004. One hundred and twenty-eight patients (10-16 years) were treated with pediatric Nordic (NOPHO) protocols, and 97 patients (17-25 years) with Finnish Leukemia Group National protocols. We characterized the biological subtypes, clinical features and outcome of these patients.

RESULTS

For the whole cohort, the remission rate was 96%, 5-year event-free survival 62% and overall survival 72%. The 5-year event-free survival was 67% for the pediatric treatment group and 60% for the adult treatment group (p=n.s.). Patients with inferior outcome were those with a white blood cell count >or= 100 x 10(9)/L, the Philadelphia chromosome and MLL. Good prognostic features were TEL-AML1, hyperdiploidy, and pediatric intermediate risk stratification.

CONCLUSIONS

Unlike all previous studies, we found that the outcome of adolescents and young adults with acute lymphoblastic leukemia treated with pediatric or adult therapeutic protocols was comparable. The success of the adult acute lymphoblastic leukemia therapy emphasizes the benefit of central referral of patients to academic centers and adherence to research protocols.

Leukocyte transfusions revisited: stem cell graft stimulation in graft failure

BACKGROUND

The aim was to evaluate the role of leukocyte transfusions (LTX) in relation to graft function during prolonged neutropenia after stem cell transplantation (SCT).

PROCEDURE

In 1989-2005, 22 SCT patients have received LTX in our unit. In all patients severe infection with profound neutropenia (<0.2 x 10(9)/L) preceded LTX. 13/22 had multi-organ failure or thrombotic microangiopathy. Irradiated leukocytes from pooled random donor products at 1.0 x 10(10) leukocytes/m(2)/day for a minimum of 3 days were used. Myeloid recovery and clinical benefit were analyzed.

RESULTS

Engraftment defined as an absolute neutrophil count (ANC) of >0.5 x 10(9)/L on three consecutive days was observed in 15/22 (68%) patients at median of 6 (range 2-25) days after LTX, and sustained engraftment (ANC of >0.5 x 10(9)/L for 4 weeks) in 11/22 (50%) patients. Clinical benefit was observed in 6/22 (27%) patients with a prolonged antecedent neutropenia, who still demonstrated rapid sustained engraftment after LTX. Ongoing thrombotic microangiopathy was associated with persistent graft failure.

CONCLUSIONS

LTX from random donors was associated with a rapid recovery of myeloid function in severely ill SCT patients. We speculate that allostimulation by LTX may have a role.

Killer-cell immunoglobulin-like receptor ligand compatibility in the outcome of Finnish unrelated donor hematopoietic stem cell transplantation

Incompatibility in killer-cell immunoglobulin-like receptor (KIR) ligand between recipient and donor of hematopoietic stem cell transplantation has been reported to lead to natural killer (NK) cell activation. This activation may result in better transplantation outcome through reduced risk of graft-versus-host (GvH) disease, relapse and mortality. In the present study the effect of KIR ligand incompatibility was investigated retrospectively in 186 unrelated stem cell transplantations performed in Finland during years 1993-2004. No clear evidence for a better outcome in cases with KIR ligand incompatibility was obtained. Transplantation-related mortality was 64% in Kaplan-Meier analysis in the GvH direction KIR ligand-mismatched group and 33% in the KIR ligand-matched group. This difference was statistically non-significant. Consequently, no support could be obtained for a beneficial effect of KIR ligand incompatibility in the present set of unrelated donor transplantations.

Expression of vascular endothelial growth factor receptor 3 and Tie1 tyrosine kinase receptor on acute leukemia cells

BACKGROUND

Recent data indicate a role for angiogenesis in hematologic malignancies. In addition to promoting new vessel growth in the bone marrow microenvironment, angiogenic factors are regulators of both hematopoietic and leukemic cells. Activation of vascular endothelial growth factor receptor 3 (VEGFR-3) and Tie1 tyrosine kinase receptor are known to promote leukemia cell survival. The details of this complex angiogenesis-related interaction are still uncertain.

PROCEDURE

We studied bone marrow samples from 73 patients with acute lymphoblastic (ALL) or myelogenous (AML) leukemia by using immunological methods.

RESULTS

Vascular endothelial growth factor receptor 3 expression was found in 15% of the samples, particularly in samples with pediatric lymphoblastic leukemias and monocytic AMLs. Tie1 protein expression was found in 11% of the samples, all of which were from adult AML patients.

CONCLUSIONS

Our findings suggest that there are angiogenesis-related differences between pediatric and adult lymphoblastic leukemias as well as between lymphoid and myeloid leukemias.

T cell regeneration in pediatric allogeneic stem cell transplantation

Delayed and/or insufficient T cell recovery post hematopoietic stem cell transplantation (HSCT) leads to an increased risk of morbidity and mortality. We evaluated thymic function and its association with T cell regeneration post HSCT and identified factors involved in the process among pediatric stem cell transplant recipients. T cell regeneration in 66 pediatric patients was prospectively followed by naive T cell phenotyping, measuring of T cell receptor excision circles (TRECs) and expression of Foxp3 by regulatory T cells for the first 18 months post HSCT. TRECs were lower pre-HSCT in children with a malignant than non-malignant primary disease or immunosuppressed controls (P=0.001). Naive T lymphocyte reconstitution and thymic recovery were slow in the recipients of allogeneic stem cell grafts post HSCT. Infections caused by herpesviruses had a prognostic impact on mortality. Children with low TRECs had a high mortality (P=0.05) and low TRECs were also associated with extensive chronic graft-versus-host disease from 6 months onwards. Low amount of Foxp3 pre-HSCT was associated with an increased mortality post HSCT (P=0.03). Our study indicates an association between impaired T cell regeneration and thymic dysfunction and the clinical post transplant complications in pediatric allogeneic stem cell transplantation.

Bone health in children and adolescents after allogeneic stem cell transplantation

BACKGROUND

This cross-sectional study evaluated the overall bone health and the prevalence of vertebral complications after stem cell transplantation (SCT) in prepubertal children and adolescents.

METHODS

A total of 44 children and adolescents (median age, 10 years) were evaluated at a median of 3.8 years after SCT for areal bone mineral density (aBMD) with dual-energy X-ray absoptiometry and for vertebral fractures with instant vertebral assessment. Pretransplant and posttransplant medications and nutritional parameters were recorded, and plasma levels of vitamin D, calcium, phosphate, and parathormone were measured.

RESULTS

Of the 44 patients, 16 (36%) had a BMD Z-score of <-1.0. The patients with low BMD did not differ from the others with regard to their clinical or biochemical characteristics. Prepubertal patients had better BMD Z-scores at all sites compared with pubertal or postpubertal subjects. This was evident especially at the hip, in which the median aBMD Z-score in prepubertal patients (-0.2; range, -0.5 to +1.7) was found to be significantly higher than in pubertal (-1.1; range, -1.5 to +0.4) and postpubertal (-1.1; range, -2.6 to +0.5) patients (P = .03). Five patients (11%) had a history of peripheral fractures. Nine patients (20%) had vertebral compression fractures, which were asymptomatic in 7 patients.

CONCLUSIONS

Approximately one-third of patients who had undergone allogeneic SCT in childhood were found to have a reduced BMD before reaching adulthood. This was due in part to inadequate BMD gain during the pubertal years. The high prevalence of asymptomatic vertebral compression fractures calls for the systematic assessment of spinal health during the posttransplantation follow-up.

Prevention and monitoring of invasive fungal infections in pediatric patients with cancer and hematologic disorders

BACKGROUND

The occurrence of invasive fungal infection (IFIs) in a pediatric hematology/oncology unit after renovation of the ventilation system, and initiating routine azole antifungal prophylaxis was monitored. In addition, the value of serial screening for Aspergillus galactomannan (GM) for diagnosing invasive aspergillosis was assessed.

PROCEDURE

A total of 98 consecutive high-risk pediatric patients were prospectively surveyed for signs of IFI and weekly monitored for serum GM. The data was not made available to treating physicians.

RESULTS

Only 2 patients had proven and 27 possible IFI based on the European Organization for Research and Treatment of Cancer/Mycoses Study Group definitions. The incidence of proven IFI was 1/31 (3.2%) in the allogeneic stem cell transplant (SCT) (Aspergillus spp), 0/26 in the autologous SCT, and 1/60 (1.6%) in the induction therapy group (C. krusei). GM was detected at least in one tested sample in 12/98 patients (12.2%), in five patients in two or more sequential samples. In the latter group, IFI was proven in one patient and could not be excluded in the others. Four of the five patients belonged to the 31 allogeneic and one to the 26 autologous SCT patients. In patients with only one positive GM test none developed signs of IFI and only one received empirical amphotericin B.

CONCLUSIONS

With the currently used preventative and prophylactic measures, IFI is uncommon in children with high-risk for infection. Regular screening for GM could be useful among allogeneic SCT patients and two positive samples should prompt further investigative procedures and pre-emptive antifungal therapy.

Pathways Through Relapses and Deaths of Children With Acute Lymphoblastic Leukemia: Role of Allogeneic Stem-Cell Transplantation in Nordic Data

Purpose

Our focus was on patients with pediatric acute lymphoblastic leukemia (ALL) who experienced relapse or died without becoming transplantation candidates. The purpose was to outline measures needed to improve the outcome.

Patients and Methods

We analyzed our population-based 20-year data on 3,385 Nordic children with ALL treated on Nordic Society for Pediatric Hematology and Oncology ALL protocols, and described the flow of these patients through relapses, remissions, and deaths as a result of toxicity, demonstrating where major patient losses occurred.

Results

In total, 854 patients (25%) had a first and 274 patients (8%) had a second ALL relapse. P for survival after the first relapse was .35 ± .02. The induction mortality (2.2%, primary; 10.3%, first relapse; 26.3%, second relapse) and remission mortality (1%, first complete remission [1CR]; 19%, second CR [2CR]) were significant; transplantation-related mortality (TRM) only represented 15% (69 of 459) of the deaths as a result of toxicity. Of the 766 patients entering 2CR, 29% underwent transplantation (P for survival, .46 ± .04), whereas 71% continued receiving chemotherapy (P for survival, .39 ± .02). Children with stem-cell transplantation indications in 2CR, if they did not undergo transplantation, generally died or had a second relapse. The patient groups that underwent transplantation in 1CR (n = 84), 2CR (n = 220), and ≥ 3CR (n = 62) represented different risk profiles. Those with allogeneic stem-cell transplantation (allo-SCT) in ≥ 3CR (P for survival, .37 ± .07) had an ALL and first relapse with favorable features.

Conclusion

Major patient losses occurred through mortality as a result of toxicity and resistant disease during the pathways before allo-SCT. After relapse, more patients were lost to mortality as a result of toxicity during conventional chemotherapy compared with TRM. After second relapse, the chance for rescue by allo-SCT in ≥ 3CR was minimal. The question of whether transplantation is recommended after ALL relapse should be carefully addressed, and more efficient relapse protocols should be launched.

Human herpesvirus-6 and -7 in pediatric stem cell transplantation

BACKGROUND

Human herpesvirus-6 (HHV-6) and -7 (HHV-7) may reactivate with immunosuppression and cause symptoms varying from subclinical to severe organ manifestations. The presence of HHV-6 and -7 and their possible association with clinical problems among pediatric recipients of stem cell grafts was studied in a single institution setting between November 1999 and December 2001.

PROCEDURE

A total of 60 patients, mean age 8.5 years, were transplanted: 2/3 received allogeneic grafts and 1/3 autologous stem cell rescue. The presence of HHV-6 and -7 was studied in blood by polymerase chain reaction (PCR) (HHV-6) and antigenemia (HHV-6 and -7).

RESULTS

Both HHV-6 and -7 were frequently present in the blood of stem cell graft recipients. No significant difference in the incidence of HHV-6 or -7 reactivations between the allogeneic and autologous patients nor recipients of sibling or unrelated donor (URD) grafts was observed. HHV-6 antigenemia was associated with fever, rash, and delayed engraftment. Among symptomatic patients two cases of encephalitis were encountered with both having HHV-6 detectable in their cerebrospinal fluid (CSF) by PCR.

CONCLUSIONS

HHV-6 and -7 seem to be common in blood both pre- and post-transplant among pediatric recipients of stem cell grafts. Prolonged reactivations appear to correlate with clinical symptoms such as fever, rash, and bone marrow suppression in the post-stem cell transplant setting (SCT), but severe complications are rare. Transient reactivations appear to be of very limited clinical significance.

Circulating dendritic cell subset levels after allogeneic stem cell transplantation in children correlate with time post transplant and severity of acute graft-versus-host disease

We examined the recovery of circulating monocytoid (Lin- CD11+ HLA-DR+) and plasmacytoid (Lin- CD123+ HLA-DR+) precursor (pre) dendritic cell (DC) subsets after allogeneic stem cell transplantation (SCT) in 39 children, using age-matched healthy children as controls. The frequencies of DCs in peripheral blood samples were determined by flow cytometry. The initial recovery of DC occurred simultaneously with myeloid engraftment. However, with time, DC subset values declined, being very low 40-50 days after SCT. Low monocytoid and plasmacytoid DC values were associated significantly with the development of severe acute graft-versus-host disease (aGVHD) (P=0.042 and 0.017, respectively). Plasmacytoid DC values were lower than in the age-matched controls for the entire follow-up period (range 102-2569 days), although, with time, values approached normal levels. Normal monocytoid DC numbers were observed within 300-400 days post SCT. The severity of chronic GVHD did not correlate with quantitative recovery of DC. We conclude that in pediatric SCT, initial recovery of DC production is concurrent with that of myelopoiesis, yet with time, DC subset values decline and low counts are associated with severe aGVHD. Monocytoid DC numbers approach normal levels within a year of SCT, but plasmacytoid DC counts recover very slowly.