Cancer surveillance series: recent trends in childhood cancer incidence and mortality in the United States

Effects of HMG on revascularization and follicular survival in heterotopic autotransplants of mouse ovarian tissue

Ovarian tissue transplantation is now considered as a procedure to preserve the fertility of young women patients undergoing cancer therapy. The present study investigated the effects and mechanism of human menopausal gonadotrophin (HMG) intervention on vascular remoulding in ovarian heterotopic autotransplantation. Ovaries of 8-week-old mice were cultured in vitro with different concentrations of HMG for 3h for measuring the expression of vascular endothelial growth factor (VEGF). The cultured ovaries were implanted under the kidney capsule and removed 24, 36, 48 h or 1 month after transplantation. Revascularization, fluid exudation and the number of surviving ovarian follicles were observed. The results showed that VEGF was increased 1.6-6.5 times in the HMG intervention groups. Revascularization appeared 24-36 h after transplantation and was earlier than that of the control. Fluid exudation increased incrementally with increasing HMG concentrations. The total number of surviving ovarian follicles was increased by 1.2-1.5 times in the HMG 0.15 IU/ml group as compared with the other groups 1 month after transplantation. It is concluded that intervention with HMG in vitro before transplantation could improve the blood supply reconstruction and survival of the autotransplanted ovarian follicles, which might be associated with increased VEGF expression.

Ovarian response to controlled ovarian hyperstimulation in cancer patients is diminished even before oncological treatment

OBJECTIVE

To evaluate the results of controlled ovarian stimulation before chemotherapy for oocyte vitrification to preserve fertility in women diagnosed with cancer and compare them with a historical control group.

DESIGN

A retrospective, multicenter, observational study performed between March 2007 and January 2011.

SETTING

University-affiliated infertility clinics.

PATIENT(S)

Of 272 patients affected by cancer in our Fertility Preservation Program, 223 women underwent a stimulated cycle for oocyte vitrification according to our protocols before cancer treatment. Their results were compared with a historical control group of 98 patients diagnosed with male factor infertility who were stimulated for a conventional IVF cycle.

INTERVENTION(S)

Controlled ovarian stimulation and oocyte retrieval.

MAIN OUTCOME MEASURE(S)

Days of stimulation, total dose of gonadotropins, estrogen levels, and number of oocytes retrieved and vitrified.

RESULT(S)

No differences were found in days of stimulation, but significant differences in E(2) levels and the number of retrieved oocytes were measured, especially in the hormone-dependent cancer group.

CONCLUSION(S)

Patients with hormone-dependent cancer had a weaker response to controlled ovarian stimulation compared with patients with non-hormone-dependent cancer. Whether the oncological disease already affects the ovaries before chemo-/radiotherapy remains to be elucidated.

Progression from first symptom to diagnosis in childhood brain tumours

This study was undertaken to investigate the evolution of clinical features between onset of symptoms and diagnosis in children with brain tumours and to identify ways of shortening the time to diagnosis. One hundred and thirty-nine children with a brain tumour were recruited from four UK paediatric neuro-oncology centres. Children had a median of one symptom or sign at symptom onset and six by diagnosis. The symptoms and/or signs experienced at symptom onset and at diagnosis were as follows: headache in 55 and 81 children, nausea and vomiting in 39 and 88 children, motor system abnormalities in 31 and 93 children, cranial nerve palsies in 24 and 75 children, visual system abnormalities in 23 and 96 children, endocrine or growth abnormalities in 10 and 35 children and behavioural change in 4 and 55 children. The median time between symptom onset and diagnosis (symptom interval) was 3.3 months. A longer symptom interval was associated with head tilt, cranial nerve palsies, endocrine and growth abnormalities and reduced visual acuity. More than half of children with brain tumours developed problems with vision and more than a third developed motor problems, cranial nerve palsies, behavioural change, or nausea and vomiting between symptom onset and diagnosis.

Clinical course of sepsis in children with acute leukemia admitted to the pediatric intensive care unit

OBJECTIVE

To describe the clinical course, resource use, and mortality of patients with leukemia admitted to the pediatric intensive care unit with sepsis and nonsepsis diagnoses over a 10-yr period.

DESIGN

Retrospective analysis.

SETTING

Tertiary medical-surgical pediatric intensive care unit at C.S. Mott Children's Hospital, University of Michigan.

PATIENTS

All patients with leukemia admitted to the pediatric intensive care unit from January 1, 1998, to December 31, 2008.

INTERVENTIONS

None; chart review.

MEASUREMENTS AND MAIN RESULTS

Clinical course was characterized by demographics, leukemia diagnosis, phase of therapy, leukocyte count on admission, presence of sepsis, steroid administration, intensity of care, and Pediatric Risk of Mortality score on admission to the pediatric intensive care unit. The primary outcome was survival to pediatric intensive care unit discharge. Among 68 single admissions to the pediatric intensive care unit with leukemia during the study period, 33 (48.5%) were admitted with sepsis. Admission to the pediatric intensive care unit for sepsis was associated with greater compromise of hemodynamic and renal function and use of stress dose steroids (p = .016), inotropic and/or vasopressor drugs (p = .01), and renal replacement therapy (p = .028) than nonsepsis admission. There was higher mortality among children with sepsis than other diagnoses (52% vs. 17%, p = .004). Also, mortality among children with sepsis was higher among those with acute lymphoblastic leukemia (60% vs. 44%) compared with acute myelogenous leukemia. Administration of stress dose steroids was associated with higher mortality (50% vs. 17%, p = .005) and neutropenia. Patients with acute lymphoblastic leukemia and sepsis showed the greatest mortality and resource use.

CONCLUSIONS

Patients with acute leukemia and sepsis had a much higher mortality rate compared with previously described sepsis mortality rates for the general pediatric intensive care unit patient populations. Patients who received steroids had an increased mortality rate, but given the retrospective nature of this study, we maintain a position of equipoise with regard to this association. Variation in mortality and resource use by leukemia type suggests further research is needed to develop targeted intervention strategies to enhance patient outcomes.

Neural tumor-initiating cells have distinct telomere maintenance and can be safely targeted for telomerase inhibition

PURPOSE

Cancer recurrence is one of the major setbacks in oncology. Maintaining telomeres is essential for sustaining the limitless replicative potential of such cancers. Because telomerase is thought to be active in all tumor cells and normal stem cells, telomerase inhibition may be nonspecific and have detrimental effects on tissue maintenance and development by affecting normal stem cell self-renewal.

METHODS

We examined telomerase activity, telomere maintenance, and stem cell maturation in tumor subpopulations from freshly resected gliomas, long-term, primary, neural tumor-initiating cells (TIC) and corresponding normal stem cell lines. We then tested the efficacy of the telomerase inhibitor Imetelstat on propagation and self-renewal capacity of TIC and normal stem cells in vitro and in vivo.

RESULTS

Telomerase was undetectable in the majority of tumor cells and specific to the TIC subpopulation that possessed critically short telomeres. In contrast, normal tissue stem cells had longer telomeres and undetectable telomerase activity and were insensitive to telomerase inhibition, which results in proliferation arrest, cell maturation, and DNA damage in neural TIC. Significant survival benefit and late tumor growth arrest of neuroblastoma TIC were observed in a xenograft model (P = 0.02). Furthermore, neural TIC exhibited irreversible loss of self-renewal and stem cell capabilities even after cessation of treatment in vitro and in vivo.

CONCLUSIONS

TIC exhaustion with telomerase inhibition and lack of telomerase dependency in normal stem cells add new dimensions to the telomere hypothesis and suggest that targeting TIC with telomerase inhibitors may represent a specific and safe therapeutic approach for tumors of neural origin.

Formulated siRNAs targeting Rankl prevent osteolysis and enhance chemotherapeutic response in osteosarcoma models

The development of osteosarcoma, the most common malignant primary bone tumor is characterized by a vicious cycle established between tumor proliferation and paratumor osteolysis. This osteolysis is mainly regulated by the receptor activator of nuclear factor κB ligand (RANKL). Preclinical studies have demonstrated that Rankl blockade by soluble receptors is an effective strategy to prevent osteolytic lesions leading to osteosarcoma inhibition. A new therapeutic option could be to directly inhibit Rankl expression by small interfering RNAs (Rkl-siRNAs) and combine these molecules with chemotherapy to counteract the osteosarcoma development more efficiently. An efficient siRNA sequence directed against both mouse and rat mRNAs coding Rankl was first validated in vitro and tested in two models of osteosarcoma: a syngenic osteolytic POS-1 model induced in immunocompetent mice and a xenograft osteocondensant model of rat OSRGA in athymic mice. Intratumor injections of Rankl-directed siRNAs in combination with the cationic liposome RPR209120/DOPE reduced the local and systemic Rankl production and protected bone from paratumor osteolysis. Although Rkl-siRNAs alone had no effect on tumor development in both osteosarcoma models, it significantly blocked tumor progression when combined with ifosfamide compared with chemotherapy alone. Our results indicate that siRNAs could be delivered using cationic liposomes and thereby could inhibit Rankl production in a specific manner in osteosarcoma models. Moreover, the Rankl inhibition mediated by RNA interference strategy improves the therapeutic response of primary osteosarcoma to chemotherapy.

Use of sentinel node biopsy for staging parameningeal rhabdomyosarcoma

Identification of nodal involvement is important for treatment planning in patients with rhabdomyosarcoma, and is facilitated by sentinel node biopsy. Although it is employed primarily for extremity tumors, we report using sentinel node biopsy in a patient with parameningeal rhabdomyosarcoma arising in the ethmoid sinus. Lymphoscintigraphy with single photon emission computed tomography following injection of tracer at the tumor site helped identify contralateral cervical node involvement not previously recognized by physical exam, cross sectional imaging, or other functional imaging. This case demonstrates how information from sentinel node identification and biopsy can change therapy recommendations in patients with parameningeal rhabdomyosarcoma.

Fertility preservation in young cancer patients

As a result of advances in treatment, almost 80% of children and adolescents who receive a diagnosis of cancer become long-term survivors. The increased survival rate of children and adolescents with cancer has resulted in a major interest in the long-term effects of cancer treatment on the possibility for future fertility. Currently established methods for the preservation of fertility are available only for pubertal males and females. Pubertal male cancer patients should be encouraged to freeze numerous sperm samples even when sperm count and motility are poor. In these cases, intracytoplasmic sperm injection is a powerful technique compared with intrauterine insemination since thawed sperm samples with poor parameters can produce relatively high fertilization rates resulting in normal pregnancies and deliveries. Married pubertal women should be proposed ovulation induction, follicular aspiration, and fertilization with husband sperm. Single women could benefit from vitrification of oocytes. This requires a delay of about 3 weeks in the commencement of chemotherapy to enable follicular growth. Fertility preservation for prepubertal patients is more of a problem. Young girls could be offered cryopreservation of gametes in the gonadal tissue. Cryopreservation of testicular tissue was suggested for fertility preservation for young boys, but this method is totally experimental and not currently offered. Discussing future fertility is part of the consultation of young female and male patients facing potentially gonadotoxic cancer therapy. It is the role of reproductive specialists to create various options in their laboratory to preserve fertility potential of cancer patients.

[Medulloblastomas: review]

INTRODUCTION

The term of "medulloblastoma" refers to cerebellar tumors belonging to the family of primitive neuro-ectodermic tumors (PNET). Medulloblastomas represent 40% of cerebellar tumors, 15 to 20% of brain tumors and the first cause of malignant brain tumors in childhood. Seventy to 80% of cases are diagnosed in children versus 20 to 30% in adults.

UPDATED KNOWLEDGE

Diagnosis is based on clinical and radiological exams, and proved on pathological analysis in association with molecular biology. Treatment comprises surgery, craniospinal radiotherapy except for children under five years of age and chemotherapy according to age and high-risk criteria. Medulloblastoma is a rare case of a central nervous system tumor which is radio- and chemo-sensitive. Treatment goals are, on one hand, to improve the survival rates and, on the other hand, to avoid late neurocognitive, neuroendocrine and orthopedic side effects related to radiation therapy, notably in children. The prognosis is relatively good, with a five year survival rate over 75% after complete resection of a localized tumor although sequelae may still compromise outcome.

PERSPECTIVES AND CONCLUSION

Management of patients with medulloblastoma implies a multidisciplinary approach combining the contributions of neurosurgery, neuroradiology, pediatric oncology, neuro-oncology and radiotherapy teams.

Detection of DNA damage in oocytes of small ovarian follicles following phosphoramide mustard exposures of cultured rodent ovaries in vitro

Healthy oocytes are critical for producing healthy children, but little is known about whether or not oocytes have the capacity to identify and recover from injury. Using a model ovotoxic alkylating drug, cyclophosphamide (CPA), and its active metabolite, phosphoramide mustard (PM), we previously showed that PM (≥3μM) caused significant follicle loss in postnatal day 4 (PND4) mouse ovaries in vitro. We now investigate whether PM induces DNA damage in oocytes, examining histone H2AX phosphorylation (γH2AX), a marker of DNA double-strand breaks (DSBs). Exposure of cultured PND4 mouse ovaries to 3 and 0.1μM PM induced significant losses of primordial and small primary follicles, respectively. PM-induced γH2AX was observed predominantly in oocytes, in which foci of γH2AX staining increased in a concentration-dependent manner and peaked 18-24h after exposure to 3-10μMPM. Numbers of oocytes with ≥5 γH2AX foci were significantly increased both 1 and 8days after exposure to ≥1μMPM compared to controls. Inhibiting the kinases that phosphorylate H2AX significantly increased follicle loss relative to PM alone. In adult mice, CPA also induced follicle loss in vivo. PM also significantly decreased primordial follicle numbers (≥30μM) and increased γH2AX foci (≥3μM) in cultured PND4 Sprague-Dawley rat ovaries. Results suggest oocytes can detect PM-induced damage at or below concentrations which cause significant follicle loss, and there are quantitative species-specific differences in sensitivity. Surviving oocytes with DNA damage may represent an increased risk for fertility problems or unhealthy offspring.

Effects of vitrification solutions and equilibration times on the morphology of cynomolgus ovarian tissues

This study assessed the effects of vitrification solutions and equilibration times on morphology of cynomolgus ovarian tissues. Ovarian cortical sections (0.1-0.2 cm thickness) of seven cynomolgus monkeys were randomly allocated to either a control group or one of six vitrification groups. Ovarian tissue sections were vitrified ultra-rapidly by placing them directly into liquid nitrogen using two different vitrification solutions (VSEGP: 5.64 mol/l ethylene glycol+5% (w/v) polyvinylpyrrolidone+0.5 mol/l sucrose; and VSED: 3.22 mol/l ethylene glycol+2.56 mol/l dimethylsulphoxide+0.5 mol/l sucrose) after three different exposure times (5-20 min). After warming, follicle morphology was analysed using light and transmission electron microscopy. The proportion of morphologically normal follicles vitrified using VSED after a 5-min exposure was lower (P<0.05) than those vitrified by other conditions. The proportion of normally structured mitochondria in oocytes of preantral follicles vitrified after a 5-min exposure to VSED (56%) was lower (P<0.01) than those vitrified by other conditions (78-88%). Following tissue vitrification with VSED, the surface ratio of lysosome was increased compared with non-vitrified oocytes (1.64% versus 1.11%; P<0.05). These results indicate that VSEGP can support the morphology of vitrified preantral follicles and oocytes.

Incidence of childhood central nervous system tumors in the Nordic countries

BACKGROUND

The incidence rates of childhood central nervous system (CNS) tumors in the Nordic countries remain among the highest in the world. Large geographical and temporal variations in the incidence rates of CNS tumors have been reported. Increasing incidence rates would be a public health concern, as they might indicate increased exposure to environmental risk factors.

METHODS

All 3,983 children 0-14 years of age registered with a primary CNS tumor in 1985-2006 in the national cancer registries of the Denmark, Finland, Norway, and Sweden were identified. Tumors were classified according to the International Classification of Childhood Cancer version 3 (ICCC-3). Join-point analysis was used to detect changes in trends and to estimate annual changes in incidence rates.

RESULTS

The mean annual incidence rate of CNS tumors was 42 per million. No statistically significant change in time trends of incidence rates was observed during 1985-2006. Furthermore, the incidence by birth cohort was relatively stable during the study period.

CONCLUSION

The incidence rates of childhood CNS tumors in the Nordic countries remain among the highest in the world. The stable incidence rates during the last 22 years indicate that major changes in environmental risk factors are unlikely.

Childhood cancer trends in a western Canadian province: a population-based 22-year retrospective study

OBJECTIVES

The objective of this study was to describe children and youth <20 years of age diagnosed with malignant cancer in Alberta, Canada over 22 years. We consider both temporal and geographical variations.

PROCEDURE

The Alberta Cancer registry was used to extract information on cancer diagnoses during April 1, 1982, and March 31, 2004. Data extracted included gender, age at diagnosis, diagnosis, and geographic information. Population data were also obtained and analyses included descriptive summaries, rates, and cluster detection tests.

RESULTS

During 22 fiscal years, 2,758 Alberta children and youth were diagnosed with malignant cancer. The average age of diagnosis was 9.6 years. The most common diagnoses were leukemia (24.8%), central nervous system (16.7%), lymphoma (15.8%), and other epithelial neoplasm and melanoma (11.2%). The number of malignant cases varied over year with crude rates of 13.4 per 100,000 in 1982/1983 to 17.3 per 100,000 in 2003/2004. Variation was also seen over diagnosis sub-group and geographic region.

CONCLUSIONS

Although a relatively rare number of children and youth in Alberta were diagnosed with cancer during the study period, there were suggestions that an increase incidence in childhood cancer occurred in later years and some geographic areas have more cases than expected by chance. Further study is required to see if emerging trends continue and explain higher rate areas.

Early changes in SOFA score as a prognostic factor in pediatric oncology patients requiring mechanical ventilatory support

PURPOSE

To evaluate whether changes in outcome prediction scores during the first 72 hours after admission to a pediatric intensive care unit (PICU) are more predictive of outcome than single assessments at admission in pediatric oncology patients requiring mechanical ventilatory support for more than 3 days.

PATIENTS AND METHODS

The medical records of 54 consecutive pediatric oncology patients requiring mechanical ventilation over 72 hours in the PICU of the Asan Medical Center, Seoul, Korea, between January 2006 and December 2008, were retrospectively reviewed.

RESULTS

Although both initial Sequential Organ Failure Assessment (SOFA) score and change in SOFA score (Δ-SOFA) correlated well with mortality, Δ-SOFA score showed a significantly stronger correlation (P<0.001) and a larger area under the receiver operating characteristic curve than did initial SOFA score. Patients with positive and negative Δ-SOFA scores showed statistically significant differences in mortality (18.5% vs. 88.2%, P<0.001). In addition, early changes in respiratory parameters, such as PaO₂/FiO₂ (P/F) ratio, oxygenation index (OI), and ventilation index (VI), evaluated serially during the first 3 days, also correlated with mortality. Patients showing improvement in these respiratory parameters displayed significantly lower mortality than did patients with worsening of these parameters (P<0.01).

CONCLUSIONS

Serial evaluation of SOFA score during the first few days after PICU admission was a good predictor of prognosis in pediatric oncology patients mechanically ventilated over 3 days. Independent of initial SOFA score, Δ-SOFA score during the first 72 hours closely correlated with outcome. Early changes in respiratory parameters, such as P/F ratio, OI, and VI, may also provide valuable prognostic information in such patients.

The epidemiology of osteosarcoma

Osteosarcoma derives from primitive bone-forming mesenchymal cells and is the most common primary bone malignancy. The incidence rates and 95% confidence intervals of osteosarcoma for all races and both sexes are 4.0 (3.5-4.6) for the range 0-14 years and 5.0 (4.6-5.6) for the range 0-19 years per year per million persons. Among childhood cancers, osteosarcoma occurs eighth in general incidence and in the following order: leukemia (30%), brain and other nervous system cancers (22.3%), neuroblastoma (7.3%), Wilms tumor (5.6%), Non-Hodgkin lymphoma (4.5%), rhabdomyosarcoma (3.1%), retinoblastoma (2.8%), osteosarcoma (2.4%), and Ewing sarcoma (1.4%). The incidence rates of childhood and adolescent osteosarcoma with 95% confidence intervals areas follows: Blacks, 6.8/year/million; Hispanics, 6.5/year/million; and Caucasians, 4.6/year/million. Osteosarcoma has a bimodal age distribution, having the first peak during adolescence and the second peak in older adulthood. The first peak is in the 10-14-year-old age group, coinciding with the pubertal growth spurt. This suggests a close relationship between the adolescent growth spurt and osteosarcoma. The second osteosarcoma peak is in adults older than 65 years of age; it is more likely to represent a second malignancy, frequently related to Paget's disease. The incidence of osteosarcoma has always been considered to be higher in males than in females, occurring at a rate of 5.4 per million persons per year in males vs. 4.0 per million in females, with a higher incidence in blacks (6.8 per million persons per year) and Hispanics (6.5 per million), than in whites (4.6 per million). Osteosarcoma commonly occurs in the long bones of the extremities near the metaphyseal growth plates. The most common sites are the femur (42%, with 75% of tumors in the distal femur), the tibia (19%, with 80% of tumors in the proximal tibia), and the humerus (10%, with 90% of tumors in the proximal humerus). Other likely locations are the skull or jaw (8%) and the pelvis (8%). Cancer deaths due to bone and joint malignant neoplasms represent 8.9% of all childhood and adolescent cancer deaths. Death rates for osteosarcoma have been declining by about 1.3% per year. The overall 5-year survival rate for osteosarcoma is 68%, without significant gender difference. The age of the patient is correlated with the survival, with the poorest survival among older patients. Complete surgical excision is important to ensure an optimum outcome. Tumor staging, presence of metastases, local recurrence, chemotherapy regimen, anatomic location, size of the tumor, and percentage of tumor cells destroyed after neoadjuvant chemotherapy have effects on the outcome.

Burden of illness in adult survivors of childhood cancers: findings from a population-based national sample

BACKGROUND

The number of adult survivors of childhood cancer in the United States is increasing because of effective treatments and improved survival. The purpose of this study was to use a national, population-based sample to estimate the burden of illness in adult survivors of childhood cancer.

METHODS

A total of 410 adult survivors of childhood cancer and 294,641 individuals without cancer were identified from multiple years of the National Health Interview Survey. Multiple measures of burden, general health, and lost productivity were compared using multivariate regression analyses including: logistic, polytomous logit, proportional odds, and linear models.

RESULTS

Controlling for the effects of age, sex, race/ethnicity, and survey year, adult survivors of childhood cancer reported poorer outcomes across the majority of general health measures and productivity measures than individuals without cancer. Survivors were more likely to report their health status as fair or poor (24.3% vs 10.9%; P<.001); having any health limitation in any way (12.9% vs 3.4%; P<.001); being unable to work because of health problems (20.9% vs 6.3%; P<.001); and being limited in the amount/kind of work because of health problems (30.9% vs 10.6%; P<.001). When categorized by time since diagnosis, cancer survivors had poor health outcomes in every time interval, with the greatest limitations in the initial 4 years after diagnosis and 30 or more years after diagnosis.

CONCLUSIONS

Across multiple measures, adult survivors of childhood cancers have poorer health outcomes and more health limitations than similar individuals without cancer.

Trends in childhood cancer incidence and mortality in urban Shanghai, 1973-2005

BACKGROUND

To describe trends in cancer incidence and mortality among children less than 15 years of age in urban Shanghai between 1973 and 2005.

PROCEDURE

Annual rates of cancer incidence were calculated per 1,000,000 children for 3-year intervals between 1973 and 2005. Linear regression models were used to analyze the annual percent change (APC) in incidence and mortality across these distinct intervals.

RESULTS

For all cancers combined, the incidence rate during the observed time period did not substantially change in urban Shanghai. Rates for the incidence of individual cancer did exhibit variations. Leukemia incidence remained relatively stable but the incidence of myeloid leukemia decreased sharply in both males (APC -8.6%) and females (APC -9.5%). The rate of NHL varied little among males with APC 2.1% and modestly increased among females with APC 9.3%. Anatomic sites that only occasionally demonstrate malignancy, bone and joints in males and endocrines in females, showed upward trends in incidence. A significant reduction in liver cancer incidence in males was observed. Examining mortality rates, all cancer mortality decreased by -6.0% annually in males and by -3.9% in females. This trend was mainly due to the reduction in mortality for leukemia, particularly the myeloid subtype, which decreased in males (APC -7.2%) and females (APC -7.3%).

CONCLUSIONS

Childhood cancer incidence rates showed no substantial changes but mortality demonstrated a dramatic reduction during the observed time period, suggesting an improvement in both childhood cancer diagnosis and treatment.

Lymphoma: a pediatrician's perspective

Since Thomas Hodgkin's paper, entitled "On Some Morbid Appearances of the Absorbent Glands and Spleen", published in 1832, an enormous body of research on lymphomas has developed. Even more research is required, however, in order to completely prevent or treat these neoplasms of the lymphocytes.

Trends in childhood leukemia in Basrah, Iraq, 1993-2007

OBJECTIVES

Through a sister-university relationship between the University of Basrah and the University of Washington, we analyzed Ibn Ghazwan Hospital's leukemia registry data to evaluate trends in childhood leukemia since 1993.

METHODS

We documented leukemia cases among children aged 0 to 14 years for each of the last 15 years. Population data were obtained from a 1997 census and various subsequent estimates to calculate rates.

RESULTS

We observed 698 cases of childhood leukemia between 1993 and 2007, ranging between 15 cases (2.6 per 100 000 annual rate) in the first year and 56 cases (6.9 per 100 000 annual rate) in the final year, reaching a peak of 97 cases in 2006 (12.2 per 100 000 annual rate).

CONCLUSIONS

Childhood leukemia rates in Basrah more than doubled over a 15-year period. The test for trend was significant (P = .03). Basrah's childhood leukemia rate compared unfavorably with neighboring Kuwait and nearby Oman, as well as the United States, the European Union, and other countries.

Pediatric acute lymphoblastic leukemia and exposure to pesticides

Organophosphates are pesticides ubiquitous in the environment and have been hypothesized as one of the risk factors for acute lymphoblastic leukemia (ALL). In this study, we evaluated the associations of pesticide exposure in a residential environment with the risk for pediatric ALL. This is a case-control study of children newly diagnosed with ALL, and their mothers (n = 41 child-mother pairs) recruited from Georgetown University Medical Center and Children's National Medical Center in Washington, DC, between January 2005 and January 2008. Cases and controls were matched for age, sex, and county of residence. Environmental exposures were determined by questionnaire and by urinalysis of pesticide metabolites using isotope dilution gas chromatography-high-resolution mass spectrometry. We found that more case mothers (33%) than controls (14%) reported using insecticides in the home (P < 0.02). Other environmental exposures to toxic substances were not significantly associated with the risk of ALL. Pesticide levels were higher in cases than in controls (P < 0.05). Statistically significant differences were found between children with ALL and controls for the organophosphate metabolites diethylthiophosphate (P < 0.03) and diethyldithiophosphate (P < 0.05). The association of ALL risk with pesticide exposure merits further studies to confirm the association.

A review of the potential association between childhood leukemia and benzene

Chronic exposure to high concentrations of benzene is an established cause of acute myeloid leukemia (AML) in occupationally exposed workers. Based on this association, it is not unreasonable to assume that children could also get AML if they were exposed to comparable levels of benzene. Fortunately, reports of such exposures and subsequent AML development in children are non-existent. However, the question of whether children can develop leukemia at far lower, environmental levels of benzene remains. The existing scientific evidence relevant to this question will be addressed in this review. While positive findings have been reported, the collective literature does not indicate that exposure to environmental levels of benzene is related to an increased risk of childhood leukemia. Our understanding of this important issue would be strengthened by additional studies that accurately characterize exposures as well as differentiate between the various forms of leukemias observed in children.

Medulloblastoma incidence has not changed over time: a CBTRUS study

Earlier studies have reported changes in the incidence of medulloblastoma (MB) but have conflicted, likely because of small sample size or misclassification of MB with primitive neuroectodermal tumor (PNET). The incidence of MB and PNET from 1985 to 2002 was determined from the Central Brain Tumor Registry of the United States, a large population-based cancer registry, using strict histologic and site codes. No statistically significant change in MB incidence was observed over the last 2 decades, but there was an increase in MB and PNET combined.

Investigating spatio-temporal similarities in the epidemiology of childhood leukaemia and diabetes

Childhood acute lymphoblastic leukaemia (ALL) and Type 1 diabetes (T1D) share some common epidemiological features, including rising incidence rates and links with an infectious aetiology. Previous work has shown a significant positive correlation in incidence between the two conditions both at the international and small-area level. The aim was to extend the methodology by including shared spatial and temporal trends using a more extensive dataset among individuals diagnosed with ALL and T1D in Yorkshire (UK) aged 0-14 years from 1978-2003. Cases with ALL and T1D were ascertained from 2 high quality population-based disease registers covering the Yorkshire region of the UK and linked to an electoral ward from the 1991 UK census. A Bayesian model was fitted where similarities and differences in risk profiles of the two diseases were captured by the shared and disease-specific components using a shared-component model, with space-time interactions. The extended model revealed a positive correlation of at least 0.70 between diseases across all time periods, and an increasing risk across time for both diseases, which was more evident for T1D. Furthermore, both diseases exhibited lower rates in the more urban county of West Yorkshire and higher rates in the more rural northern and eastern part of the region. A differential effect of T1D over ALL was found in the south-eastern part of the region, which had a more pronounced association with population mixing than with population density or deprivation. Our approach has demonstrated the utility in modelling temporally and spatially varying disease incidence patterns across small geographical areas. The findings suggest searching for environmental factors that exhibit similar geographical-temporal variation in prevalence may help in the development and testing of plausible aetiological hypotheses. Furthermore, identifying environmental exposures specific to the south-eastern part of the region, especially locally varying risk factors which may differentially affect the development of T1D and ALL, may also be fruitful.

Anatomical and histopathological profile of head and neck neoplasms in Persian pediatric and adolescent population

BACKGROUND

Neoplasms of the head and neck region are relatively uncommon in childhood. The present study aimed to describe and compare the anatomical and histopathological distribution of head and neck neoplasms in Persian pediatric and adolescent population.

METHODS

Patients who presented with primary head and neck tumors were included in this study. Orbital and skin tumors and neoplasms with secondary (metastatic) involvement of the head and neck were excluded from the study. Based on the data obtained from a tertiary referral hospital tumor registry and oncology department, a total of 152 benign and malignant neoplasms of the head and neck in patients aged 19 years or younger (99 boys), whom were reported to this institution between 2000 and 2007, were analyzed in this study. This number represented 10% of all pediatric and adolescent population.

RESULTS

The patients' age at presentation was 1-19 years (median 12 years). The peak incidence was observed in the adolescent population (34.2% of patients). There were 136 (89.5%) malignant tumors and 16 (10.5%) benign neoplasms. Cervical lymph nodes, nasopharynx, sinonasal and salivary glands were the most frequent primary sites and accounted for 60% of all primary sites. Lymphomas [Non-Hodgkin's lymphomas (30%), Hodgkin's disease (25%)], carcinomas (20%), and sarcomas (10.5%) were the most frequent histopathological types.

CONCLUSION

The most frequent primary site, malignant histopathological type, and male-female ratio in our study were comparable with other reported series; however, the ratio of benign to malignant lesions is different from most studies.

Trends in adult leukemia incidence and survival in Denmark, 1943-2003

The etiology of leukemia is largely unknown. Ecological data indicating trends in incidence and survival can provide information about changes in risk factors, can reflect underlying changes in diagnostic classification, and can measure therapeutic advances. From the records of the Danish Cancer Registry with registration starting from 1943, we calculated age-specific, period-specific, and age-standardized (world standard) incidence rates of chronic lymphoid leukemia (CLL), acute lymphoid leukemia (ALL), chronic myeloid leukemia (CML), and acute myeloid leukemia (AML) for persons above the age of 18. Kaplan-Meier survival curves and median survival times were calculated. Between 1943 and 2003, there were 26,036 cases of leukemia reported. The age-specific incidence rates of CLL, CML, and AML were higher for older men and women, while the incidence rates of ALL by age were more homogeneous. The age-standardized incidence rates during the study period increased for CLL and AML, increased less strongly for ALL, and decreased for CML in both men and women, although the incidence rates for women were almost always lower. Patients with CLL had the longest survival time in all age groups. The median survival time increased for all leukemia subtypes throughout the period of study most pronounced for CLL since 1950 and CML since 1990.

Incidence of primary central nervous system tumors among children in Belgrade (Serbia), 1991-2004

The aim of this survey was to estimate the incidence of primary CNS tumors among children aged 0-14 in Belgrade during the period 1991-2004. Incidence rates were age-adjusted according to the world standard population. The average age-adjusted incidence rates were 3.4/100,000 for boys, 2.4/100,000 for girls, and 2.9/100,000 for both genders. There was a nonsignificant tendency toward increased CNS tumor incidence (y = 2.547 + 0.052 x, p = .549). The age-specific incidence rates were 3.0/100,000 (0-4 years), 2.2/100,000 (5-9 years), and 3.8/100,000 (10-14 years). Among the population aged between 0 and 14, the cumulative probability of acquiring primary CNS tumors was 1 per 1961 for boys and 1 per 2778 for girls. Astrocytoma was the most common pathohistological type of primary CNS tumors accounting for 41.5% of cases.

Childhood cancers in a referral hospital in northern Nigeria

BACKGROUND

We undertook this study to determine the relative frequencies of childhood malignancies and their age - sex distribution in this environment.

MATERIALS AND METHODS

Hospital-based data of histological and cytologically confirmed cases of malignancies in children, aged ≤ 15 years, was collated over a period of 11 years, from the Cancer Registry.

RESULTS

A total of 329 children aged ≤ 15 years, with confirmed malignant disease, was recorded. This constituted 8.44% of all malignancies diagnosed in the same period with a Male : Female ratio of 1.5:1. Burkitt's lymphoma accounted for 27.01% of the cases followed by retinoblastoma (17.02%), non-Hodgkin's non-Burkitt's Lymphoma (9.42%), and Rhabdomyosarcoma (9.42%). Others were Nephroblastoma (8.81%), Hodgkin's lymphoma (6.69%), Neuroblastoma (3.34%), Colorectal carcinoma (2.43%), Osteosarcoma (2.13%), and Unspecified lymphomas (1.82%). Burkitt's lymphoma was most prevalent in the 5-9 and 10-15 year age groups, retinoblastoma in the 0-4 year age group, and Non-Hodgkin's lymphoma, Hodgkin's lymphoma, and unspecified carcinomas were more prevalent in the 10-15 year age group.

CONCLUSION

Lymphomas were the most prevalent malignancies of childhood seen in this region and the majority were of the Burkitt type, in contrast to the predominant leukemic and central nervous system trend seen in developed nations.

Targets for active immunotherapy against pediatric solid tumors

The potential role of antibodies and T lymphocytes in the eradication of cancer has been demonstrated in numerous animal models and clinical trials. In the last decennia new strategies have been developed for the use of tumor-specific T cells and antibodies in cancer therapy. Effective anti-tumor immunotherapy requires the identification of suitable target antigens. The expression of tumor-specific antigens has been extensively studied for most types of adult tumors. Pediatric patients should be excellent candidates for immunotherapy since their immune system is more potent and flexible as compared to that of adults. So far, these patients do not benefit enough from the progresses in cancer immunotherapy, and one of the reasons is the paucity of tumor-specific antigens identified on pediatric tumors. In this review we discuss the current status of cancer immunotherapy in children, focusing on the identification of tumor-specific antigens on pediatric solid tumors.

Herpes simplex virus oncolytic therapy for pediatric malignancies

Despite improving survival rates for children with cancer, a subset of patients exist with disease resistant to traditional therapies such as surgery, chemotherapy, and radiation. These patients require newer, targeted treatments used alone or in combination with more traditional approaches. Oncolytic herpes simplex virus (HSV) is one of these newer therapies that offer promise for several difficult to treat pediatric malignancies. The potential benefit of HSV therapy in pediatric solid tumors including brain tumors, neuroblastomas, and sarcomas is reviewed along with the many challenges that need to be addressed prior to moving oncolytic HSV therapy from the laboratory to the beside in the pediatric population.

Dermatofibrosarcoma protuberans: A case report of a rare, bulky tumor that was managed with surgical therapy

We report a case of this rare tumor and describe the surgical approach that we adopted and the clinical outcome; we also report his condition at 24 months' follow-up. Although treatment was with radical surgery, sufficient shoulder function could be obtained in our patient. We also describe the interesting MR findings of this tumor which correlated well with the histopathologic findings.

Epidemiology of leukaemia and lymphoma in children and young adults from the north of England, 1990-2002

AIM

We aimed to describe and contrast the epidemiology of haematological malignancies among 0-14 and 15-24-year-olds in northern England from 1990 to 2002 and compare clinical trial entry by age group.

PATIENTS AND METHODS

Incidence rates were examined by age, sex and period of diagnosis and differences were tested using Poisson regression. Differences and trends in survival were assessed using Cox regression.

RESULTS

1680 subjects were included comprising 948 leukaemias and 732 lymphomas. Incidence rates for acute lymphoblastic leukaemia were significantly higher for 0-14 compared to 15-24-year-olds, whilst Hodgkin lymphoma showed the reverse. No significant changes in incidence were observed. 60% of leukaemia patients aged 15-24 years entered trials compared to 92% of 0-14-year-olds. Survival rates were significantly lower and improved less markedly over time for 15-24 compared to 0-14-year-olds, particularly for leukaemia.

CONCLUSIONS

Trial accrual rates need to be improved amongst 15-24-year-olds and a more structured follow-up approach adopted for this unique population.

Childhood and adolescent cancer survival in the US by race and ethnicity for the diagnostic period 1975-1999

BACKGROUND

Survival trends provide a measure of improvement in detection and treatment over time. In the current study, updated childhood and adolescent cancer survival statistics are presented, overall and among demographic subgroups, including Hispanics, for whom to the authors' knowledge national rates have not been previously reported. These results extend those provided by the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program in their detail and interpretation.

METHODS

Survival trends of primary cancers in children and adolescents (ages birth to 19 years) were evaluated using SEER 9 data. Five-year and 10-year relative survival rates across 5-year (1975-1979, 1985-1989, and 1995-1999) and 10-year (1975-1984 and 1985-1994) cohorts were compared via Z-tests. Annual percent change (APC) in survival was computed via weighted least-squares regression. Rates in Hispanic children and adolescents were compared with those in non-Hispanic whites and blacks (SEER 13, 1995-1999).

RESULTS

Five-year survival rates increased significantly overall (1975-1979: 63% vs 1995-1999: 79%; P< .0001) and for nearly all histologic types examined; increases were greatest for ependymoma (+37%; P< .0001) and non-Hodgkin lymphoma (+34%; P< .0001). Hispanic children and adolescents had somewhat poorer 5-year rates than non-Hispanic whites overall (74% vs 81%; P< .0001) and for Ewing sarcoma, leukemia, central nervous system tumors, and melanoma. Ten-year rates also increased significantly overall (1975-1984: 61% vs 1985-1994: 72%; P< .0001) and for a majority of cancer types. The largest improvements were noted for acute lymphoblastic leukemia (+19%; P< .0001) and non-Hodgkin lymphoma (+19%; P< .0001).

CONCLUSIONS

Observed trends reinforce the need for resources devoted to advancing treatment modalities, reducing disparities among racial/ethnic groups and adolescents, and providing long-term care of survivors.

New Technologies for Diagnosing Pediatric Tumors Expert Opinion on Medical Diagnostics

BACKGROUND: The completion of Human Genome Project (HGP) has paved the way for novel, more detailed and accurate molecular diagnostic classification of cancer. With the information from the HGP, cancers can be categorized not only on the morphology or limited immunohistological markers, but according to their "molecular fingerprints" such as gene expression profiles. Technologies detecting these signatures have been developed to simultaneously measure multiple genes or proteins in one assay with high sensitivity and specificity. OBJECTIVE: To evaluate potential innovative novel methods of diagnosis and prognosis in pediatric cancers. METHODS: We selected a variety of promising new diagnostic technologies utilizing molecular signatures which harness the results from HGP including DNA microarray, bead-based detection system, multiplexed RT-PCR, MesoScale Discovery (MSD), and isotope-coded affinity tag (ICAT), as well as their applications in biomarker discovery for pediatric tumors. Label-free detection technologies and the obstacles for taking these new diagnostic technologies from the bench to the bedside are also discussed. CONCLUSION: The use of molecular signatures is gaining acceptance in clinical practice. However, technical challenges need to be addressed before incorporating these new technologies into current diagnostic and prognostic schema.

Childhood cancer in Sudan: 1999–2007

There is paucity of information on childhood cancer from Sudan with the last studies published more than 20 years ago. This study aims to provide a current picture of childhood cancer in Sudan. Data was obtained from the hospital registry for the period May 1999 to June 2007 on all paediatric patients presenting to the Institute of Nuclear Medicine and Oncology, University of Gezira, Wad Madani, Sudan. There were 322 children with cancer during this time period with a male:female ratio of 1.6:1. Lymphomas (111, 35%), leukaemia (83, 26%) and Wilms' tumour (43, 13%) were the three most common groups of tumours. Thirty percent of all lymphomas were Burkitt's lymphoma; 3.4% of all childhood cancer cases were nasopharyngeal carcinomas.

Cancer incidence among children and adolescents in the United States, 2001-2003

OBJECTIVE

Our goal was to describe current childhood cancer incidence in the United States and identify demographic and geographic variation among children and adolescents with cancer.

METHODS

We examined data from 39 National Program of Cancer Registries and 5 Surveillance, Epidemiology, and End Results statewide registries (representing >90% of the US population) to identify cancers diagnosed among persons aged 0 to 19 from 2001-2003. Diagnosed cancers were grouped by the third version of the International Childhood Cancer Classification. Analyses were stratified according to gender, age, race, ethnicity, and US census region. A multivariable negative binomial regression model was used to evaluate demographic and geographic differences in incidence for all cancers combined.

RESULTS

We identified 36446 cases of childhood cancer with an age-adjusted incidence rate of 165.92 per million. Stratified analyses showed that, for all cancers combined, boys had a significantly higher rate than girls; children (aged 0-14 years) had a significantly lower rate than adolescents (aged 15-19 years); and white children had the highest incidence rate among all races. Young people living in the Northeast had the highest incidence rate among all US census regions, which may be partially attributed to significantly higher incidence rates for central nervous system neoplasms and lymphomas in this region compared with other US census regions. Negative binomial regression analysis demonstrated that the childhood cancer-incidence rate varied significantly according to gender, age, race, ethnicity, and geography.

CONCLUSIONS

This study is the first to demonstrate substantial regional differences in the incidence of childhood cancer. It also shows that incidence varies according to gender, age, race, and ethnicity. Our research findings are useful for prioritizing future childhood cancer research needs.