Basic principles of paediatric radiotherapy

The Landscape of Pediatric Radiation Oncology in Nigeria

Radiation therapy (RT) is an essential part of the multidisciplinary treatment of pediatric cancer. Over the past five decades, significant advances have been made in the delivery of RT, with better dose delivery to disease targets while minimizing exposure to nearby organs at risk. These advances have led to improved treatment outcomes, increased survival, and reduced treatment-related toxicities. Advanced treatment techniques, however, require significant investment in infrastructural and personnel resources. This review documents what is currently available regarding expertise and infrastructure for pediatric radiation oncology practice in Nigeria. It was performed to serve as a foundation for the creation and design of tailored solutions (initiatives and policies) to increase pediatric radiation availability, accessibility, and equity in Nigeria and ultimately improve pediatric cancer treatment outcomes in the region.

"Superhero" concept to avoid anesthesia for daily radiation treatment in childhood cancer

Advancements in therapeutic interventions have led to significant improvement in the overall management of childhood cancer. Radiotherapy forms an important component of their treatment. Modern radiotherapy technique where an optimal therapeutic ratio can be obtained demands proper and adequate immobilization of the child. This can be technically challenging sometimes, particularly when the child is noncompliant. To address this hurdle, we have used this concept of "Superhero," where we have decorated and painted the thermoplastic masks that often used in the head and neck and cranial irradiation. We have received adequate compliance for this method, and the need for anesthesia was slackened.

Evaluation of Ultra-low-dose Paediatric Cone-beam Computed Tomography for Image-guided Radiotherapy

AIMS

In image-guided radiotherapy, daily cone-beam computed tomography (CBCT) is rarely applied to children due to concerns over imaging dose. Simulating low-dose CBCT can aid clinical protocol design by allowing visualisation of new scan protocols in patients without delivering additional dose. This work simulated ultra-low-dose CBCT and evaluated its use for paediatric image-guided radiotherapy by assessment of image registration accuracy and visual image quality.

MATERIALS AND METHODS

Ultra-low-dose CBCT was simulated by adding the appropriate amount of noise to projection images prior to reconstruction. This simulation was validated in phantoms before application to paediatric patient data. Scans from 20 patients acquired at our current clinical protocol (0.8 mGy) were simulated for a range of ultra-low doses (0.5, 0.4, 0.2 and 0.125 mGy) creating 100 scans in total. Automatic registration accuracy was assessed in all 100 scans. Inter-observer registration variation was next assessed for a subset of 40 scans (five scans at each simulated dose and 20 scans at the current clinical protocol). This subset was assessed for visual image quality by Likert scale grading of registration performance and visibility of target coverage, organs at risk, soft-tissue structures and bony anatomy.

RESULTS

Simulated and acquired phantom scans were in excellent agreement. For patient scans, bony atomy registration discrepancies for ultra-low-dose scans fell within 2 mm (translation) and 1° (rotation) compared with the current clinical protocol, with excellent inter-observer agreement. Soft-tissue registration showed large discrepancies. Bone visualisation and registration performance reached over 75% acceptability (rated 'well' or 'very well') down to the lowest doses. Soft-tissue visualisation did not reach this threshold for any dose.

CONCLUSION

Ultra-low-dose CBCT was accurately simulated and evaluated in patient data. Patient scans simulated down to 0.125 mGy were appropriate for bony anatomy set-up. The large dose reduction could allow for more frequent (e.g. daily) image guidance and, hence, more accurate set-up for paediatric radiotherapy.

Role and toxicity of radiation therapy in neuroblastoma patients: A literature review

Neuroblastoma is the most common extracranial solid tumor, arising from primitive sympathetic ganglion cells, in pediatric patients. The unique features of neuroblastoma include variable clinical behaviors, such as rapid progression to death and maturation to benign ganglioneuroma, followed by regression. Radiation therapy (RT) is usually administered to both the primary tumor bed and persistent metastatic sites after induction chemotherapy for high-risk neuroblastoma. RT to the tumor bed after surgical resection contributes significantly to local disease control and prevention of local relapse, confirming the role of RT. Palliative radiotherapy for metastatic neuroblastoma is also effective and safe and mainly provides symptomatic relief. The late side effects of RT in neuroblastoma patients include growth and developmental failure, hypothyroidism, gastrointestinal dysfunction, neurocognitive defects, pulmonary and cardiac abnormalities, infertility, and secondary cancers. In this article, we reviewed the role and toxicity of RT in neuroblastoma patients.

Ewing-like sarcoma/undifferentiated round cell sarcoma in an infant with APC and MSH6 variation: A case report

RATIONALE

Ewing-like sarcoma (ELS)/undifferentiated round cell sarcoma (URCS) is a rare type of soft tissue sarcomas (STS), especially in infants, with poor prognosis. It is a so-called "small round cell" sarcoma, and has many features of Ewing sarcoma, but lacks rearrangements in EWSR1. The diagnosis and treatment of this kind of STS remains challenging. BCOR genetic abnormalities have been found in some Ewing-like sarcomas.

PATIENT CONCERNS

This report presents an ELS case of a female infant, who was 2 months old when initially diagnosed, with the clinical stage of IIIA (G2T2N0M0). Histologic findings revealed an undifferentiated neoplasm composed of small round tumor cells with round, open chromatic nuclei, and scant cytoplasm in a sheet growth pattern. Fluorescence in situ hybridization (FISH) analysis showed absence of EWSR1 and ETV6 gene rearrangement. Molecular genetic testing found no established variants of clinical significance but variants of unknown significance in APC, KMT2D, and MSH6 were detected. Immunostaining revealed that the tumor cells were positive for TLE1 and BCOR, and negative for cytokeratin (AE1/AE3), Desmin, CD45, S100, CD31, HMB45, and SATB2. INI-1 was retained.

DIAGNOSIS

Ewing-like sarcoma (ELS)/undifferentiated round cell sarcoma (URCS) INTERVENTIONS:: After initial diagnosis, the patient received 4 cycles of combination chemotherapy for 2 months. Radical amputation of left upper extremity was performed 3 months after diagnosis. Postoperative chemotherapy was continued for 6 cycles.

OUTCOMES

The patient died of intracranial metastasis with hemorrhage in 13 months after initial diagnosis, 5 months after the last cycle of chemotherapy.

LESSONS

ELS in infancy is extremely rare and has a poorer prognosis than Ewing sarcoma or infantile fibrosarcoma. APC and MSH6 variation might be related with the disease progression and predict a poorer prognosis. This rare case promotes better understanding of the disease and suggests a promising role for the combination chemotherapy regimen in treating infantile ELS. Importantly, it brings to light the possibility of intracranial metastasis, which requires proactive screening for timely detection.

Social Inequalities Along the Childhood Cancer Continuum: An Overview of Evidence and a Conceptual Framework to Identify Underlying Mechanisms and Pathways

Inequalities in health according to social conditions are regarded as unnecessary and unjust. There is a large body of evidence on inequalities in adult cancer, observable throughout the societies on a national level as well as on a global scale. Socioeconomic influences on health matter at all ages including childhood, for which childhood cancer is the leading cause of disease related death in high-income countries (HICs). Substantial differences in the reported incidence of childhood cancers have been observed globally by socioeconomic development of a population. This is reflected in the higher incidence rates reported for HICs, particularly for acute lymphoblastic leukemia, and for cancer in infants (below 1 year), compared to low- and middle-income countries (LMICs). Considerable inequalities between populations and degree of socioeconomic development are also noted for survival from childhood cancer, with substantially lower survival rates seen in most LMICs compared to HICs. With respect to inequalities by socioeconomic position (SEP) within countries, findings of an association between SEP and childhood cancer risk are diverse and limited to studies from HICs. On the contrary, observations on social inequalities in survival within countries are accumulating and indicate that survival inequalities do not only concern resource-poor countries but also high-income populations including European countries. In turn, a childhood cancer diagnosis in itself may have implications on the parents' socioeconomic situation as well as on the later socioeconomic life after having survived the disease. The underlying mechanisms and causal pathways of these empirically demonstrated social inequalities are poorly understood, although it is of significant public health relevance for any actions or strategies to reduce childhood cancer-related inequity. We propose a conceptual framework on potential underlying mechanism and pathways specifically addressing social inequalities in childhood cancer and after childhood cancer to (i) illustrate potential pathways by which social determinants may create health inequities at different points of the childhood cancer continuum; (ii) illustrate potential pathways by which a childhood cancer diagnosis may impact the socioeconomic situation of the concerned family or the later life of a childhood survivor; and (iii) point out how major determinants may relate to each other.

Surviving childhood cancer: a systematic review of studies on risk and determinants of adverse socioeconomic outcomes

Substantial improvements in childhood cancer survival have resulted in a steadily increasing population of childhood cancer survivors. Whereas somatic late effects have been assessed in many studies, less is known about the impact of childhood cancer on socioeconomic outcomes in survivors. The aim of this article was to evaluate and summarise the evidence on the socioeconomic conditions of childhood cancer survivors and to identify survivors at particular risk of adverse socioeconomic outcomes. An extensive literature search of three electronic databases was conducted. Of 419 articles identified, 52 met the inclusion criteria. All the selected articles were appraised for quality, and findings were summarised in a narrative synthesis. Childhood cancer survivors were at higher risk of adverse socioeconomic outcomes with regard to educational achievement, income and social security benefits than the general population or a sibling comparison group. The risks for unemployment and a lower occupational position were significantly increased only for survivors of a central nervous system tumour. Notably, survivors of central nervous system tumours, survivors treated with cranial radiotherapy and those diagnosed at younger age independent of cancer type were determinants of particular adverse socioeconomic outcomes. Given the increasing population of childhood cancer survivors, targeted follow-up interventions and support strategies addressing not only the somatic and psychiatric late effects but also the socioeconomic difficulties that some childhood cancer survivors face is of high importance to reduce social inequity, and ensure a high quality of life after childhood cancer.

Spontaneous regression of laryngeal carcinoma in 10 year old boy: A case report and review of literature

Laryngeal carcinoma is a rare pathology in children, with only 92 cases reported. Spontaneous regression of laryngeal carcinoma is even more unique clinical event, so far only observed in adults. In this report we present an extraordinary case of a 10 year old patient with laryngeal squamous cell carcinoma that underwent spontaneous regression.

Evaluation of administered dose using portal images in craniospinal irradiation of pediatric patients

This study aimed to assess the administered dose based on portal imaging in craniospinal pediatric irradiation by evaluating cases in which portal images did or did not account for the total administered dose. We also intended to calculate the mean increase in total administered dose. Data were collected from General University Hospital Gregorio Marañón; we evaluated the total dose administered, total dose planned, number of portal images per treatment and corresponding monitor units of two different groups: one in which the dose from portal images is deducted from the total administered dose (D), and another in which it was not (N). We used descriptive statistics to analyze the collected data, including the mean and respective standard deviation. We used the Shapiro-Wilk and Spearman rank correlation coefficient tests and estimated the linear regression coefficients. Patients in group D received a mean dose of 29.00 ± 10.28 cGy based on the verification portal images, a quantity that was deducted from the planned dose to match the total administered dose. Patients in group N received a mean dose of 41.50 ± 30.53 cGy, which was not deducted from the planned dose, evidencing a mean increase of 41.50 ± 30.55 cGy over the total administered dose. The acquisition of the set-up verification portal images, without their inclusion in the total administered dose, reflects an average increase in total dose for craniospinal irradiation of pediatric patients. Subtraction of the monitor units used to acquire the verification images is recommended.

Early Glottic Squamous Cell Carcinoma in a 16-Year-Old: Case Report, Review of the Literature and Pediatric Head and Neck Radiotherapy Guidelines

Squamous cell carcinoma in children and adolescents is extremely rare. Less than 80 case reports have been reported in the literature since it was first reported in 1868. In this article, we intend to report a case where a 16-year-old girl who presented with complaints of change in voice was found to have early-stage vocal cord carcinoma on evaluation.

Epidemiology of brain tumors in children aged two and under: A 10-year single-institute study

The aim of present study was to evaluate the incidence, clinical symptoms, pathological characteristics, surgical treatment strategies and prognosis of brain tumors in children aged two and under. The current study obtained data regarding 32 consecutive infants and young children aged two years and under, who were treated for brain tumors in the Children’s Hospital of Fudan University (Shanghai, China) between 2003 and 2013. The types of tumor, clinical manifestations, location, histological features, applied treatment strategies and outcomes were retrospectively evaluated. The male to female ratio was 1.13:1, and among a total of 32 tumors, 14 (43.8%) were suptratentorial and 18 (56.3%) were infratentorial. Intracranial hypertension was the most common onset symptom, and astrocytoma was the most common tumor type (10 cases; 31.3%), followed by ependymoma (nine cases; 28.1%) and medulloblastoma (six cases; 18.8%). Surgical tumor resection was performed in 20 patients (62.5%), who experienced a mean post-operative survival time of 67.6 months. By contrast, conservative treatment with medications was administered in 12 patients (37.5%), with a mean survival time of 25.3 months. Furthermore, four patients underwent conservative therapy combined with ventriculoperitoneal shunting to relieve intracranial pressure arising from cerebrospinal fluid accumulation, resulting in a mean survival time of 10.5 months. In conclusion, the present study indicates that surgical tumor resection may improve the overall prognosis of infants and young children aged two years and under who presented with brain tumors. In addition, ventriculoperitoneal shunts may facilitate pre- and post-operative improvement in clinical symptoms by relieving intracranial pressure; however, the shunts do not appear to increase long-term survival. Furthermore, high surgical risk is an important prognostic factor in this pediatric patient population.