[A PhD completed. Long-term effects of childhood cancer therapy on oral health]. / Serie: Hora est. Langetermijneffecten van de behandeling van kinderkanker op de mondgezondheid.

In recent years, the five-year survival rate for childhood cancer has increased to about 80%. However, childhood cancer therapy can have serious long-term adverse effects on general health later in life. Of survivors, 75% experience 1 or more late effects. This PhD research aimed to gain more insight into the long-term effects on oral health of childhood cancer therapy, 15 years or more after diagnosis. This study, which is part of the Dutch Childhood Cancer Survivor Study Late Effects 2 (DCCSS LATER 2 Study), showed that oral complications such as dental developmental disorders and hyposalivation occur frequently. Most important risk factors were head and neck radiotherapy of the salivary glands, (alkylating) cytostatic agents, and age at the time of the cancer diagnosis. Dentists should be aware of childhood cancer in the medical history of their patient and of the type of therapy received. Regular dental visits are an essential part of long-term follow-up care of childhood cancer survivors.

Reproductive intentions and use of reproductive health care among female survivors of childhood cancer.

STUDY QUESTION: Do female childhood cancer survivors (CCSs) express a decreased desire to have children and do they use reproductive health care more often compared to women without a history of cancer? SUMMARY ANSWER: Overall, no difference was found in the desire to have children between CCSs and controls, whereas CCSs consult a fertility specialist more often, at a younger age, and sooner after their first attempt at conceiving. WHAT IS KNOWN ALREADY: Female CCSs may face a shorter than anticipated reproductive window as a result of their cancer treatment. Little is known about their desire to have children and use of reproductive health care, especially in relation to their former cancer treatment. STUDY DESIGN, SIZE, DURATION: This study is part of the DCOG LATER-VEVO study, a nationwide retrospective cohort study on female fertility in Dutch CCSs. In total, 1749 CCSs and 1673 controls were invited for the study. Data collection took place between January 2008 and May 2014. PARTICIPANTS/MATERIALS, SETTING, METHODS: Data on the desire to have children and use of reproductive health care were collected by questionnaire. The control group consisted of sisters from CCSs and females from the general population. In total, 1106 (63%) CCSs and 818 (49%) controls completed the questionnaire. MAIN RESULTS AND THE ROLE OF CHANCE: Overall, no difference was found in the desire to have children between CCSs and controls (86% and 89%, respectively). However, survivors of a CNS tumour were less likely to desire children and CCSs without biological children at time of study were more likely to report that their desire to have children was unfulfilled because of medical reasons (9%), compared to controls (1%). In total, 12% of CCSs ever consulted a fertility specialist compared to 10% of controls (OR = 1.7, 95% CI: 1.3-2.4). Mean (SD) age at time of their first visit was 27.7 (4.4) years for CCSs and 29.9 (3.9) years for controls (P < 0.01). In total, 43% of CCSs consulted a fertility specialist within 12 months after they had started trying to achieve a pregnancy, compared to 27% of controls. Risk factors for consulting a fertility specialist included a previous diagnosis of renal tumour, leukaemia, lymphoma or a CNS tumour, and treatment with alkylating chemotherapy, gonadotoxic radiotherapy or both. In total, 70% of CCSs reported a female factor as cause of subfertility compared to 34% of controls (OR = 4.5, 95% CI: 2.3-8.7) and in this specific group, CCSs seemed more likely to use fertility treatment (OR = 2.9, 95% CI: 1.0-8.2). LIMITATIONS, REASONS FOR CAUTION: Because of the low number of CCSs who used fertility treatment, we were not able to look at specific diagnoses and treatment types associated with using fertility treatment. Nevertheless, we were able to identify diagnostic- and treatment-related risk factors for consulting a fertility specialist. Details regarding consultations with a fertility specialist and fertility treatment were based on self-report and may therefore be subject to recall bias. WIDER IMPLICATIONS OF THE FINDINGS: Decisions about parenthood affect all CCSs. It's important to evaluate reproductive intentions and function timely after cancer treatment, so CCSs can be adequately counselled regarding family planning and fertility treatment. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the Dutch Cancer Society (Grant no. VU 2006-3622) and the Children Cancer Free Foundation (Project no. 20). TRIAL REGISTRATION NUMBER: NTR2922.

Long-term effects of childhood cancer treatment on hormonal and ultrasound markers of ovarian reserve.

STUDY QUESTION: Which treatment-related factors are (dose-dependently) associated with abnormal hormonal and ultrasound markers of ovarian reserve in female childhood cancer survivors (CCSs)? SUMMARY ANSWER: Cyclophosphamide, procarbazine, a composite group of 'other alkylating agents', dactinomycin, doxorubicin, mitoxantrone, spinal radiotherapy (RT), abdominal/pelvic RT and total body irradiation were multivariably associated with abnormal ovarian reserve markers, with dose-effect relationships being established for procarbazine and abdominal/pelvic RT. WHAT IS KNOWN ALREADY: Female childhood cancer survivors are at an increased risk of reduced ovarian function and reserve, but knowledge regarding the long-term effects of individual chemotherapeutic (CT) agents and radiotherapy fields and their respective doses is limited. STUDY DESIGN, SIZE, DURATION: The DCOG LATER-VEVO is a nationwide retrospective cohort study in which measurements were performed between 2008 and 2014. In total, 1749 female 5-year CCSs, diagnosed before age 18 years between 1963 and 2002 and 1201 controls were invited for the study. PARTICIPANTS/MATERIALS, SETTING, METHODS: Ovarian reserve was assessed by anti-Müllerian hormone (AMH), follicle stimulating hormone (FSH), inhibin B levels, and antral follicle counts (AFC). The study was a multicentre study including all seven Dutch Centers for Paediatric Oncology/Haematology. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 564 CCs and 390 controls participated in the clinical part of the study. Overall, 7.0-17.7% of CCSs and 2.4-13.6% of controls had abnormal ovarian reserve markers. Above age 35, significantly more CCSs than controls had abnormal ovarian reserve markers (AMH: 26% vs. 4%; AFC: 20% vs. 3%; inhibin B: 42% vs. 16%). For AMH and FSH, significant differences were also found below age 35. Cyclophosphamide, procarbazine, a group of 'other alkylating agents', dactinomycin, doxorubicin, mitoxantrone, spinal RT, abdominal/pelvic RT and total body irradiation were multivariably associated with at least one abnormal ovarian reserve marker. Dose-effect relationships were established for procarbazine and abdominal/pelvic RT. LIMITATIONS, REASONS FOR CAUTION: Despite the large scale of the study, dose-effect relationships could not be investigated for all types of treatment due to a limited numbers of participants for specific analyses. WIDER IMPLICATIONS OF THE FINDINGS: This study demonstrated that the majority of CCSs do not show signs of a reduced ovarian reserve. However, specific subgroups of CCSs appear to be associated with a high risk. Our results are important for counselling CCSs and future patients regarding parenthood and fertility preservation. STUDY FUNDING/COMPETING INTERESTS: This study was funded by the Dutch Cancer Society (Grant no. VU 2006-3622) and by the Children Cancer Free Foundation (Project no. 20). Philips Health Systems Benelux supported this study by providing three ultrasound systems and concomitant analytic software. There are no competing interests. TRIAL REGISTRATION NUMBER: NTR2922 http://www.trialregister.nl/trialreg/admin/rctview.asp?TC = 2922.

Fertility studies in female childhood cancer survivors: selecting appropriate comparison groups.

Little information is available on the use of appropriate comparison groups for studies investigating late effects of childhood cancer. Two comparison groups in a nationwide study on reproductive function and ovarian reserve in female childhood cancer survivors were recruited (The Dutch Childhood Oncology Group Long-Term Effects After Childhood Cancer Cohort Study). Experiences of this process are reported. Two types of comparison groups were used: sisters of participating survivors and controls from the general population. A total of 352 out of 580 (61%) of the participating survivors who had a sister gave permission to invite them for the study. The participation rate of sisters was much higher than control participants from the general population (74% versus 21%, respectively), whereas considerably more effort was involved in recruiting controls from the general population. Participants in this group were significantly older and more highly educated than sister controls (P < 0.001 for both groups). No significant differences were observed between both types of comparison groups in several fertility-related characteristics, suggesting minimal bias owing to selective participation. Researchers setting up a study to investigate late effects among survivors of childhood cancer should carefully consider the advantages and disadvantages of using various types of comparison groups.

Validity of self-reported data on pregnancies for childhood cancer survivors: a comparison with data from a nationwide population-based registry.

STUDY QUESTION: To what degree do records registered in the Netherlands Perinatal Registry (PRN) agree with self-report in a study questionnaire on pregnancy outcomes in childhood cancer survivors (CCSs)? SUMMARY ANSWER: This study suggests that self-reported pregnancy outcomes of CCSs agree well with registry data and that outcomes reported by CCSs agree better with registry data than do those of controls. WHAT IS KNOWN ALREADY: Many studies have shown that childhood cancer treatment may affect fertility outcomes in female CCSs; however, these conclusions were often based on questionnaire data, and it remains unclear whether self-report agrees well with more objective sources of information. STUDY DESIGN, SIZE, DURATION: In an nationwide cohort study on fertility (inclusion period January 2008 and April 2011, trial number: NTR2922), 1420 CCSs and 354 sibling controls were invited to complete a questionnaire regarding socio-demographic characteristics and reproductive history. In total, 879 CCSs (62%) and 287 controls (81%) returned the questionnaire. PARTICIPANTS/MATERIALS, SETTING, METHODS: The current validation study compared the agreement between pregnancy outcomes as registered in the PRN and self-reported outcomes in the study questionnaire. A total of 589 pregnancies were reported in CCSs, and 300 pregnancies in sibling controls, of which 524 could be linked to the PRN. MAIN RESULTS AND THE ROLE OF CHANCE: A high intra-class correlation coefficient (ICC) was found for birthweight (BW) (0.94 and 0.87 for CCSs and controls, respectively). The self-reported BWs tended to be higher than reported in the PRN. For gestational age (GA), the ICC was high for CCSs (0.88), but moderate for controls (0.49). CCSs overestimated GA more often than controls. The Kappa values for method of conception and for method of delivery were moderate to good. Multilevel analyses on the mean difference with regard to BW and GA showed no differences associated with time since pregnancy or educational level. LIMITATIONS, REASONS FOR CAUTION: Not all pregnancies reported could be linked to the registry data. In addition, the completeness of the PRN could not be assessed precisely, because there is no information on the number of missing records. Finally, for some outcomes there were high proportions of missing values in the PRN registry. WIDER IMPLICATIONS OF THE FINDINGS: Our study suggests that questionnaires are a reliable method of data collection, and that for most variables, self-report agrees well with registry data. STUDY FUNDING/COMPETING INTEREST: This work was supported by the Dutch Cancer Society (grant no. VU 2006-3622) and by Foundation Children Cancer Free. None of the authors report a conflict of interest. TRIAL REGISTRATION NUMBER: NTR2922 http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2922.

Chronic fatigue in childhood cancer survivors is associated with lifestyle and psychosocial factors; a DCCSS LATER study.

BACKGROUND: The purpose of this study was to determine factors associated with chronic fatigue (CF) in childhood cancer survivors (CCS). PATIENTS AND METHODS: Participants were included from the Dutch Childhood Cancer Survivor Study (DCCSS) LATER cohort, a nationwide cohort of CCS (≥5 years after diagnosis) and siblings as controls. Fatigue severity was assessed with the 'fatigue severity subscale' of the Checklist Individual Strength ('CIS-fatigue'). CF was defined as scoring ≥35 on the 'CIS-fatigue' and having fatigue symptoms for ≥6 months. Twenty-four parameters were assessed, categorized into assumed fatigue triggering, maintaining and moderating factors. Multivariable logistic regression analyses were carried out to investigate the association of these factors with CF. RESULTS: A total of 1927 CCS participated in the study (40.7% of invited cohort), of whom 23.6% reported CF (compared with 15.6% in sibling controls, P < 0.001). The following factors were associated with CF: obesity [versus healthy weight, odds ratio (OR) 1.93; 95% confidence interval (CI) 1.30-2.87], moderate physical inactivity (versus physical active, OR 2.36; 95% CI 1.67-3.34), poor sleep (yes versus no, OR 2.03; 95% CI 1.54-2.68), (sub)clinical anxiety (yes versus no, OR 1.55; 95% CI 1.10-2.19), (sub)clinical depression (yes versus no, OR 2.07; 95% CI 1.20-3.59), pain (continuous, OR 1.49; 95% CI 1.33-1.66), self-esteem (continuous, OR 0.95; 95% CI 0.92-0.98), helplessness (continuous, OR 1.13; 95% CI 1.08-1.19), social functioning (continuous, OR 0.98; 95% CI 0.97-0.99) and female sex (versus male sex, OR 1.79; 95% CI 1.36-2.37). CONCLUSION: CF is a prevalent symptom in CCS that is associated with several assumed maintaining factors, with lifestyle and psychosocial factors being the most prominent. These are modifiable factors and may therefore be beneficial to prevent or reduce CF in CCS.

Health-related quality of life in Dutch adult survivors of childhood cancer: A nation-wide cohort study.

AIM: To investigate the health-related quality of life (HRQOL) of Dutch adult childhood cancer survivors (CCS) and to identify risk factors of impaired HRQOL. METHODS: Adult CCS (age >18, diagnosed <18, ≥5 years since diagnosis) from the Dutch LATER registry completed the Medical Outcome Study Short Form 36 (SF-36) to measure HRQOL and provided sociodemographic characteristics. Age-adjusted mean SF-36 scale scores of CCS were compared to the Dutch general population for men and women separately using t-tests, with effect size d. Multivariate logistic regression models were built to identify sociodemographic and cancer-related risk factors for impaired physical and mental HRQOL. RESULTS: Both male and female CCS (N = 2301, mean age = 35.4 years, 49.6% female) reported significantly (p ≤ .005) worse HRQOL than the general population on almost all scales of the SF-36 (-.11 ≤ d ≤ -.56). Largest differences were found on vitality and general health perceptions. Significant risk factors (p ≤ .05) for impaired physical HRQOL were female sex, older age at diagnosis, not having a partner, low educational attainment, disease recurrence and exposure to radiotherapy, specifically to lower extremity radiation. Odds ratios (ORs) ranged from 1.6 to 3.7. Significant risk factors for impaired mental HRQOL were age 26-35 years, male sex, not having a partner and low educational attainment. ORs ranged from 1.3 to 2.0. CONCLUSION: Adult CCS had worse HRQOL than the general population. CCS most at risk were those with low educational attainment and without a partner. Adult CCS could benefit from routine surveillance of their HRQOL. Special attention for CCS' vitality and health perceptions and beliefs is warranted.

[Tooth development disturbances following haematopoietic stem cell transplantation]. / Langetermijneffecten op de gebitsontwikkeling na stamceltransplantatie.

Forty children treated with allogenic haematopoietic stem cell transplantation for haematological malignancies, were examined at least 2 years after transplantation. The researchers collected information concerning subjective oral symptoms, the results of a panoramic radiograph and the findings of an oral examination. Nearly all children had tooth development disturbances, including missing teeth, shortened roots, and arrested root development. The study group showed a significantly higher prevalence of missing teeth than the standard values for first and second premolars in both maxilla and mandible, as well as for second molars in the mandible. Children younger than 3 years of age at the start of the treatment missed significantly more teeth than older children. The mean root-crown length ratios of several tooth types were lower when compared with a control group of healthy Finnish children. The mean dental age was higher than the mean chronological age due to early final apical root formation.

Pregnancy, time to pregnancy and obstetric outcomes among female childhood cancer survivors: results of the DCOG LATER-VEVO study.

PURPOSE: To evaluate pregnancy rates, time to pregnancy (TTP) and obstetric outcomes in female childhood cancer survivors (CCSs) and to identify specific diagnosis- and treatment-related factors associated with these outcomes. METHODS: The study is part of the DCOG LATER-VEVO study, a nationwide multicenter cohort study evaluating fertility among long-term Dutch female CCSs. Data were collected by questionnaire. The current study included 1095 CCSs and 812 controls, consisting of sisters of CCSs and a random sample of women from the general population. RESULTS: Among the subgroup of women who ever had the desire to become pregnant, the chance of becoming pregnant was significantly lower for CCSs than controls (OR 0.5, 95%CI 0.4-0.8). Moreover, TTP was 1.1 times longer for CCSs compared to controls (p = 0.09) and was significantly longer in survivors of CNS and renal tumours. Overall, no differences were found between CCSs and controls regarding the probability of ever having had a miscarriage, still birth, or induced abortion. However, CCSs had a significantly increased risk of delivering preterm (OR 2.2, 95%CI 1.3-3.7) and delivering via caesarean section (OR 1.8, 95%CI 1.2-2.6). Treatment with lower abdominal/pelvic radiotherapy was strongly associated with several adverse obstetric outcomes. CONCLUSION: CCSs are less likely to have ever been pregnant. Among those who do become pregnant, certain subgroups of CCSs are at increased risk of longer TTP. Moreover, as pregnant CCSs, especially those treated with lower abdominal/pelvic radiotherapy, are more likely to develop various adverse obstetric outcomes, appropriate obstetric care is highly advocated.

Long-term adverse effects of hematopoietic stem cell transplantation on dental development in children.

PURPOSE: The purpose of this study was to assess late effects of cytotoxic therapy with hematopoietic stem cell transplantation (HCT) on dental development in survivors of childhood cancer. MATERIALS AND METHODS: Forty children who underwent allogeneic HCT for a variety of hematological malignancies were evaluated at a minimum of 2 years after transplantation. We obtained information on oral symptoms, exposed panoramic radiographs (PRG), and performed an oral examination. PRGs were scored for agenesis and root and/or crown abnormalities. The root-crown ratio was calculated, and dental age was assessed using Demirjian' s method. MAIN RESULTS: The studied group showed a significantly higher prevalence of tooth agenesis compared to normative data for first and second premolars in both the maxilla and mandible, as well as the second molars in the mandible (all p values <0.001). Children who were <3 years old at the time of cancer treatment had significantly more missing teeth than older children, F(2,37) = 7.58, p < 0.002. Root-crown ratios were lower in the study sample than those from normative data. In addition, the mean dental age was higher (as a result of earlier apical root closure) than the mean chronological age, t(28) = 2.47, p < 0.020. CONCLUSIONS: Nearly all children examined had dental development disturbances, including agenesis, short roots, and arrested root development. An oral/dental evaluation and preventative oral supportive care regimens should be part of programs monitoring late effects in long-term survivors of childhood cancer.

Abnormal liver enzymes two years after haematopoietic stem cell transplantation in children: prevalence and risk factors.

To establish the prevalence of elevated liver enzymes in children transplanted in a Dutch haematopoietic stem cell transplantation (HSCT) centre, we retrospectively assessed AST and ALT values at 2 years after HSCT. Age, sex, diagnosis, type of transplant, conditioning regimen and early post-transplant complications involving the liver (veno-occlusive disease, acute GVHD, viral reactivation) were analysed as risk factors. AST and ALT values were available at 2 years after HSCT in 216 of 290 patients (75%) alive at that time and were above normal in 53 (25%) and at least twice normal in 17 (8%) patients. Older age at HSCT and a diagnosis of benign haematological disease are risk factors for abnormal liver enzymes late after HSCT. In half of the patients with benign haematological disease, iron overload is the most likely aetiological factor. Chronic hepatitis B or C is uncommon in our centre. In conclusion, the prevalence of abnormal liver enzymes late after HSCT in our centre is lower than reported in previous studies. Abnormal liver enzymes occur more often in children who are older at HSCT and transplanted for benign haematological disease. Long-term follow-up is crucial to establish if elevated liver enzymes precede clinical liver disease.

Permanent diffuse alopecia after haematopoietic stem cell transplantation in childhood.

Permanent alopecia after haematopoietic stem cell transplantation (HSCT) is distressing and few studies have investigated this late effect. The aim of the study was to assess the percentage of patients with alopecia and investigate risk factors for alopecia. Patients who underwent allogeneic HSCT before age 19 years, from January 1990 to January 2013, who were at least 2 years after transplant and in follow-up in our clinic were included. Alopecia was defined as clinically apparent decreased hair density. Possible risk factors considered for alopecia after HSCT included: gender, age, diagnosis, donor type, conditioning regimen: cranial irradiation (TBI/cranial radiotherapy) and/or chemotherapy, which chemotherapeutic agents were used and acute/chronic GvHD. The percentage of permanent alopecia in our cohort was 15.6% (41/263 patients). All patients had diffuse alopecia except for one with alopecia totalis. In multivariate analysis, a conditioning regimen with busulphan and busulphan plus fludarabine (odds ratio (OR) 5.7 (confidence interval (CI): 2.5-12.7) and OR 7.4 (CI: 3.3-16.2), respectively, was the main risk factor and associated with alopecia independent of acute/chronic GvHD. Neither TBI nor other alkylating chemotherapy, including treosulfan, was associated with alopecia. In conclusion, permanent alopecia after HSCT is associated with busulphan and GvHD and occurs in 16% of patients.

State-of-the-art fertility preservation in children and adolescents undergoing haematopoietic stem cell transplantation: a report on the expert meeting of the Paediatric Diseases Working Party (PDWP) of the European Society for Blood and Marrow Transplantation (EBMT) in Baden, Austria, 29-30 September 2015.

Nowadays, allogeneic haematopoietic stem cell transplantation (allo-HSCT) is a well-established treatment procedure and often the only cure for many patients with malignant and non-malignant diseases. Decrease in short-term complications has substantially contributed to increased survival. Therefore long-term sequelae are reaching the focus of patient care. One of the most important risks of stem cell transplant survivors is infertility. As well as in the field of allo-HSCT also the field of reproductive medicine has achieved substantial advances to offer potential options for fertility preservation in both boys and girls. Access to these procedures as well as their financing differs significantly throughout Europe. As all European children and adolescents should have the same possibility, the Paediatric Diseases Working Party of the European Society for Blood and Marrow Transplantation organised an expert meeting in September 2015. This manuscript describes the recommendations for the diagnosis and pre-emptive procedures that should be offered to all children and adolescents in Europe who have to undergo an allo-HSCT.

Fertility preservation issues in pediatric hematopoietic stem cell transplantation: practical approaches from the consensus of the Pediatric Diseases Working Party of the EBMT and the International BFM Study Group.

Fertility preservation is an urgent challenge in the transplant setting. A panel of transplanters and fertility specialists within the Pediatric Diseases Working Party of the European Society for Blood and Marrow Transplantation (EBMT) and the International BFM Study Group provides specific guidelines. Patients and families should be informed of possible gender- and age-specific cryopreservation strategies that should be tailored according to the underlying disease, clinical condition and previous exposure to chemotherapy. Semen collection should be routinely offered to all postpubertal boys at the diagnosis of any disease requiring therapy that could potentially impair fertility. Testicular tissue collection might be offered to postpubertal boys; nevertheless, its use has been unsuccessful to date. Oocyte collection after hormonal hyperstimulation should be offered to postpubertal girls facing gonadotoxic therapies that could be delayed for the 2 weeks required for the procedure. Ovarian tissue collection could be offered to pre-/post-pubertal girls. Pregnancies have been reported after postpubertal ovarian tissue reimplantation; however, to date, no pregnancy has been reported after the reimplantation of prepubertal ovarian tissue or in vitro maturation of pre-/post-pubertal ovarian tissue. Possible future advances in reproductive medicine could change this scenario. Health authorities should prioritize fertility preservation projects in pediatric transplantation to improve patient care and quality of life.

Incidence and severity of crucial late effects after allogeneic HSCT for malignancy under the age of 3 years: TBI is what really matters.

Younger children are considered to be more vulnerable to late effects (LE), which prompted us to study LE in patients after haematopoietic stem cell transplantation (HSCT) for a haematological malignancy before the age of 3. In this multicentre EBMT study, cumulative incidence (CI) and severity of endocrine LE, central nervous system complications and secondary malignancies at 5, 10, 15 and 20 years of follow-up were assessed. Risk factors (RF) like gender, diagnosis, age at and year of HSCT, TBI- or chemo-conditioning and GVHD were analysed. CI of any LE was 0.30, 0.52, 0.66 and 0.72 at 5, 10, 15 and 20 years after HSCT, respectively. In 25% of the patients, LE were severe at a median follow-up of 10.4 years. In multivariate analysis, only TBI was a RF for having any LE and for thyroid dysfunction and growth disturbance. Female gender was a RF for delayed pubertal development. Some more insight could be gained by descriptive analysis regarding the role of TBI and GVHD on the severity of LE. Although only five selected LE have been studied and median follow-up is relatively short, the incidence and severity of these LE are considerable but not different from what has been found in older children and TBI is the main RF.

Long-term renal function after hemopoietic stem cell transplantation in children.

Glomerular function of all long-term survivors who underwent hemopoietic stem cell transplantation (HSCT) from 1991 to 1998 (study I, n=121) was studied retrospectively. In addition, we prospectively analyzed glomerular and tubular function of all long-term surviving children who received an HSCT between 1998 and 2000 (study II, n=41). We found a lower prevalence of children with chronic renal failure (CRF) post-HSCT in our more recent cohort (study II: 10%) as compared to the older cohort (study I: 24%) 5.0 (0.7 s.d.) and 7.6 (2.4 s.d.) year's post-HSCT, respectively. Furthermore, it seems that renal function may stabilize after 1-year post-HSCT. None of the patients required dialysis or antihypertensive medication at long-term follow-up. The sole predictor of CRF in our study was high serum creatinine pre-HSCT (P=0.007), while acute renal failure within 3 months after HSCT (P=0.08) only showed a trend towards predicting CRF. We could not confirm a relation of conditioning with irradiation with CRF post-HSCT, as was shown in several other pediatric and adult studies. Proximal and distal tubular dysfunction only occurred in a minority of long-time survivors of HSCT (3-12 and 9-13%, respectively) and had no clinical consequences.

In vitro cytotoxicity of aplidin and crossresistance with other cytotoxic drugs in childhood leukemic and normal bone marrow and blood samples: a rational basis for clinical development.

To determine the potential of aplidin as a cytotoxic agent in pediatric leukemia, we tested bone marrow (BM) and peripheral blood (PB) samples (n=72) of children with different types of leukemia and healthy children in the methyl-thiazol-tetrazolium assay. Also, we compared these results with other cytotoxic drugs. Aplidin was cytotoxic in vitro at nanomolar concentrations, in a dose-dependent fashion. L-carnitine, that is applied in clinical studies to prevent myotoxicity caused by aplidin, had no effect on aplidin cytotoxicity in vitro. Aplidin cytotoxicity in vitro was not different when initial and relapsed acute lymphoblastic leukemia (ALL) or initial ALL and initial acute myeloid leukemia were compared. However, normal BM (n=19) and PB (n=13) cells were more resistant to aplidin than leukemic cells (median two- to seven-fold, P=0.001 and median four- to 11-fold, P&<0.0001, respectively). In leukemia samples, no significant crossresistance between aplidin and other cytotoxic drugs was found, except for a trend for correlation with 2',2'-difluorodeoxycytidine (rho=0.71, P=0.02). In normal BM samples, significant crossresistance with the epipodophyllotoxins was found, which is not readily explained by the currently known mechanisms of action of aplidin. In conclusion, we show that aplidin has selective cytotoxicity in vitro towards childhood leukemia cells and generally lacks crossresistance with other known cytotoxic drugs, which warrants clinical studies.

Disturbances of growth and endocrine function after busulphan-based conditioning for haematopoietic stem cell transplantation during infancy and childhood.

It is generally assumed that busulphan/cyclophoshamide (Bu/Cy)-based conditioning regimens for haematopoietic stem cell transplantation (SCT) do not affect growth. We evaluated growth and endocrine function after Bu/Cy-based conditioning in 64 children without a history of irradiation. Mean height standard deviation scores remained stable, but unexplained disturbances of growth after SCT were found in 17/48 (35%) of the children without growth-limiting disorders (10/23 in patients treated for haematological malignancies). In 10 patients, growth hormone (GH) secretion status was evaluated, and insufficient GH secretion was diagnosed in four patients. Thyroid function was evaluable in 52 patients. Two developed antibody-mediated thyroid disorders and 10 (19%) compensated primary hypothyroidism. Gonadal function was evaluable in 21 patients and was normal in all seven patients treated with low-dose Bu (8 mg/kg), whereas seven of the 14 children receiving high-dose Bu (16-20 mg/kg) developed gonadal failure; the majority of these patients had not been exposed to gonadotoxic therapy prior to Bu/Cy. Of the 49 evaluable patients, 16 developed subclinical hyperparathyroidism. We conclude that, besides gonadal and thyroid dysfunction, impaired growth and hyperparathyroidism often occur after Bu/Cy conditioning for SCT and that growth impairment may be the result of insufficient GH secretion.

The duration of fixation influences the yield of HCV cDNA-PCR products from formalin-fixed, paraffin-embedded liver tissue.

The extent of hepatitis C virus (HCV) RNA loss during increasing periods of fixation of liver tissue in formalin was examined. For this purpose human liver tissue, known to be HCV RNA positive and stored at -70 degrees C until use, was cut into small slices (n = 9), which were fixed in phosphate-buffered formalin for increasing periods of time before embedding in paraffin. Nucleic acids were extracted from each slice of formalin-fixed, paraffin-embedded liver tissue and HCV RNA loss during fixation was semi-quantified by testing 10-fold dilutions of each extract in an HCV cDNA-PCR assay. The endpoint dilution for HCV RNA detection by cDNA-PCR in liver slices fixed in buffered formalin for 8-24 h was comparable to the endpoint dilutions found for 'fresh', non-fixed liver slices. After fixation for 2-3 days the endpoint dilution for HCV RNA detection was 10(2) to 10(3)-fold less. After 2-4 weeks of formalin-fixation, HCV RNA was detectable from undiluted nucleic acid extracts only. It is concluded that formalin-fixed, paraffin-embedded liver biopsies can be used for HCV RNA detection by cDNA-PCR, on condition that the liver tissue has been embedded in paraffin within 24 h of formalin-fixation.

New developments in hepatitis C.

Since the detection of hepatitis B virus (HBV) in the 1960s and hepatitis A virus in the 1970s, a considerable proportion of infections of (probably viral) hepatitis could not be classified. About 90% of transfusion-related hepatitis was identified as non-A/non-B. In 1988 investigators from the Chiron Company (USA) detected the non-A, non-B agent and named it hepatitis C virus (HCV). An anti-HCV antibody assay (ELISA) and subsequently confirmation tests (immunoblot and polymerase chain reaction) were developed. HCV infection results in a chronic carrier state of the virus in about 80%. Almost all HCV carriers have, irrespective of their liver function tests, histologic signs of chronic hepatitis and/or liver cirrhosis. Chronic HCV infection is, like HBV, also associated with the development of hepatocellular carcinoma. Most HCV carriers are infected by parenteral routes (intravenous drug use, blood transfusion, tattooing). Intravenous drug users and haemophilia patients have the highest risk (80-90%) of becoming infected. Sexual and perinatal transmission does not play an important role in spreading the infection. Antiviral therapy (alpha-interferon) in patients with chronic hepatitis C will normalize liver function tests in about 25% of the cases, but it is unclear if the HCV carrier state will disappear and if liver cirrhosis will be prevented. At present no specific immunoglobulin or vaccine preparations are available to prevent the HCV infection.