Intracranial Germ Cell Tumors.

Intracranial germ cell tumors are rare tumors occurring in adolescents and young adults, which include germinomas and non-germinomatous type germ cell tumors (NGGCT). In the past few decades, cooperative trial groups in Europe and North America have developed successful strategies to improve survival outcomes and decrease treatment-related toxicities. New approaches to establishing diagnosis have deferred the need for radical surgery. The 5-year event-free survival (EFS) is above 90% and even patients who present with metastatic germinoma can still be cured with chemotherapy and craniospinal irradiation. The combination of surgery, chemotherapy, and radiation therapy is tailored to patients based on grouping and staging. For NGGCT, neoadjuvant chemotherapy followed by delayed surgery for residual disease and radiotherapy can yield a 5-year EFS of 70%. Further strategies should focus on reducing long-term complications while preserving high cure rates.

Impact of treatment refusal and abandonment on survival outcomes in pediatric osteosarcoma in Southeast Asia: A multicenter study.

BACKGROUND: Treatment refusal and abandonment (TxRA) are major barriers to improving outcomes among children with sarcomas of the extremities as curative treatment options bearing on amputation or disfiguring surgery, particularly in countries with limited resources. A multi-institutional retrospective study was conducted to determine the predictive factors for TxRA among patients with osteosarcoma associated with survival outcomes across Southeast Asia (SEA). METHODS: Pediatric patients with osteosarcoma treated between January 1998 and December 2017 in four SEA pediatric oncology centers from three countries were studied. Nelson-Aalen estimates, Kaplan-Meier method, and Cox's proportion hazard model were applied to address the cumulative incidence, survival outcomes, and to identify prognostic factors associated with TxRA. RESULTS: From a total of 208 patients with osteosarcoma enrolled; 18 (8.7%) patients refused and 41 (19.7%) patients abandoned treatment. Income classification of countries, age at diagnosis, tumor size, disease extent, chemotherapy protocols, and types of surgery were associated with TxRA. Tumor size more than 15 cm was an independent risk factor associated with TxRA. The 5-year overall and relapse-free survivals were 49.4% and 50.4%, respectively. However, these rates declined further to 37.9% and 35.8%, respectively, when TxRA were considered as events. Tumor size larger than 15 cm and metastatic disease were independent risk factors associated with TxRA-sensitive outcomes. CONCLUSION: The prevalence of TxRA was high in SEA, particularly in lower middle-income countries. Factors associated with TxRA related to tumor burden. Treatment outcomes could be substantially improved by lowering the refusal and abandonment rates.

Epidemiology of childhood malignant mediastinal masses and clinical factors associated with intensive care unit admission: A Singapore experience.

AIM: Majority of mediastinal masses in children are malignant. These masses are complex to manage as they have a risk of compression to surrounding structures. Many of these children have to be managed in the intensive care unit (ICU). Hence we sought to evaluate the local epidemiology of malignant mediastinal masses in children and their clinical presentation, and identified factors associated with ICU admission so that at-risk patients may be identified early. METHODS: This study is a retrospective review of institutional case records of 56 children below 18 years of age from 2000 to 2015 with a malignant mediastinal mass. We collected data on their presenting symptoms, clinical signs, radiological investigations, treatment and correlated these factors with admission to our ICU. RESULTS: Lymphoma was most common diagnosis, comprising 37 children (66.0%). There were 6 patients with neuroblastoma (10.7%), 3 patients with germ-cell tumour (5.4%) and 10 patients with T-cell acute lymphoblastic leukaemia (17.9%). Overall, 21 patients (37.5%) had to be admitted to the ICU. Almost all patients (98.2%) were symptomatic on presentation, of which lymphadenopathy was the most common (69.6%). Factors that are significantly associated with ICU admission are stridor, pericardial effusion and need for pleural drainage. CONCLUSIONS: Malignant mediastinal masses in children in our institution range from leukaemias and lymphomas to germ cell tumours and neuroblastomas, of which almost all are symptomatic. These children have a risk of cardiorespiratory collapse and many of them require intensive care. We identified factors that are associated with ICU admission, with the aim of early intervention of at-risk cases.

The Role of Natural Killer Cells as a Platform for Immunotherapy in Pediatric Cancers.

PURPOSE OF REVIEW: We aim to review the most recent findings in the use of NK cells in childhood cancers. RECENT FINDINGS: Natural killer cells are cytotoxic to tumor cells. In pediatric leukemias, adoptive transfer of NK cells can bridge children not in remission to transplant. Interleukins (IL2, IL15) can enhance NK cell function. NK cell-CAR therapy has advantages of shorter life span that lessens chronic toxicities, lower risk of graft versus host disease when using allogeneic cells, ability of NK cells to recognize tumor cells that have downregulated MHC to escape T cells, and possibly less likelihood of cytokine storm. Cytotoxicity to solid tumors (rhabdomyosarcoma, Ewing's sarcoma, neuroblastoma) is seen with graft versus tumor effect in transplant and in combination with antibodies. Challenges lie in the microenvironment which is suppressive for NK cells. NK cell immunotherapy in childhood cancers is promising and recent works aim to overcome challenges.

Sino-orbital desmoid tumor in a pediatric patient - Case report with review of literature.

We report a case of a 2-year-old female who presented with bilateral progressive proptosis, visual loss, nasal obstruction, and breathing difficulty. Magnetic resonance imaging revealed a large sino-orbital mass that was extending to the orbital apex and skull base. An initial diagnosis of rhabdomyosarcoma was made elsewhere on the basis of the presence of round and spindle cell tumor. Subsequent biopsy with immunohistochemical staining was positive for nuclear staining with ß-catenin, shifting the diagnosis to a myofibroblastic tumor, favoring desmoid-type fibromatosis. With image guidance, near complete excision of tumor was performed by a multidisciplinary team, while respecting danger zones such as the skull base and the optic nerve. Following a recurrence over 2 months, additional excision was performed with a 6-month treatment of methotrexate and vinblastine. Desmoid tumor is a rare form of soft tissue tumor uncommonly seen in the orbital area. Although benign, it is known to be recurrent and infiltrative. Few data are known and further information will aid in the management of these tumors.

Ovarian germinoma accelerating the presentation of diabetes mellitus.

A 12-year-old girl presented to the Children's Emergency Department with symptoms of diabetes mellitus. Glutamic acid decarboxylase autoantibodies and anti-Islet cell antibodies were absent. She was also found to have ovarian dysgerminoma with markedly elevated serum ß-human chorionic gonadotropin (ß-HCG). With treatment of her ovarian tumor and normalization of the serum ß-HCG her insulin therapy was quickly discontinued and metformin started. The ovarian dysgerminoma appeared to have accelerated the presentation of severe diabetes. We hypothesized that the elevated ß-HCG and possibly other placental hormones from the germ cell tumor caused her to develop insulin resistance and inadequate ß-cell insulin secretory response.

Management and Outcomes of Pediatric Craniopharyngioma: A 15-Year Experience in Singapore.

BACKGROUND: Craniopharyngiomas arise from the Rathke pouch and account for 1.2%-18.4% of pediatric primary brain tumors. Despite relatively good survival outcomes, patients face long-term morbidity from recurrences, visual impairment, and endocrinopathies, which reduce quality of life. We examined the management of pediatric craniopharyngiomas, their recurrences, and subsequent neuroendocrine sequelae in a tertiary center in South-East Asia. METHODS: A retrospective cohort of 12 paediatric patients (aged ≤18 years) with histologically confirmed diagnosis of craniopharyngioma treated from January 2002 to June 2017 was conducted. Data collected included demographics, clinical presentation, imaging data, treatment details, postoperative sequelae, and outcomes on mortality and recurrence. Survival analysis was conducted using Cox-proportional hazards model. RESULTS: The median follow-up time was 6.60 years (1.9-11.5 years). The mean age was 7.6 years (standard deviation 4.8) and 7 patients (58.3%) were male. The most common presenting symptoms were raised intracranial pressure (7, 58.3%), visual deficits (6, 50.0%), and preoperative endocrine abnormalities (2, 16.7%). Five patients underwent gross total resection (41.7%), and 7 underwent subtotal resection (58.3%). Overall survival was 75.0% (9 patients), and recurrence was 58.0% (7 patients). Median time-to-recurrence was 5.87 months (0.23-33.7, interquartile range 15.8), and median progression-free survival was 4.16 years (0.18-10.1, interquartile range 5.29). CONCLUSIONS: Long-term management of pediatric craniopharyngioma remains difficult, with multiple recurrences and long-term neuroendocrine sequelae impairing quality of life for patients. Further research into management of recurrences and neuroendocrine sequelae, as well as novel therapies to improve outcomes in these patients, may be warranted.

Paediatric brain tumours in Singapore: A 15-year epidemiological and outcome study.

Paediatric brain tumours (PBTs) are the most common solid tumours in children. Previous publications reflect variations in incidence rates and frequency of histological types in different global populations. However, there are limited studies on the epidemiology of PBTs in Singapore. This study aims to summarise the epidemiology of paediatric brain tumours managed in Singapore. This is an ethics-approved retrospective study of all patients below 19 years old diagnosed with PBTs managed by Singapore's 2 tertiary paediatric neurosurgical centres, KK Women's and Children's Hospital (KKH) and the National University Hospital (NUH) over a 15-year period from 01 January 2002 to 31 December 2017. Data collected was analysed for age, gender, tumour characteristics, presenting complaints, location, treatment modalities, 1-year and 5-year overall survival (OS). A total of 396 patients were included. The mean age of diagnosis was 7.05 years (0.25-18; ± 4.83) and male-to-female ratio was 1.41:1. Top histological groups were astrocytic (30.6%), embryonal (26.0%), germ cell (11.1%), ependymoma (30, 7.58%) and craniopharyngioma (27, 6.82%). Outcomes included recurrence rate (31.2%), 1-year OS (89.5%) and 5-year OS (72.2%). Poorer 5-year OS were noted in embryonal tumours (47.0%; p < 0.001) and ependymoma (50.0%; p = 0.0074) patients. Of note, the following cohorts also had poorer OS at 5 years: supratentorial tumours (76.2%; p = 0.0426), radiotherapy (67.4%; p = 0.0467) and surgery (74.9%, HR; p < 0.001). Overall, our data reflects patient demographics, presenting complaints, treatment modalities and survival outcomes, that are comparable to other international paediatric neurosurgical centres.

A "Wait-and-See" Approach to Quiescent Single-System Langerhans Cell Histiocytosis to Spare Children From Chemotherapy.

Background: Langerhans Cell Histiocytosis (LCH) is a childhood disorder of histiocytes that is generally treated with systemic chemotherapy. Spontaneous resolution has been previously reported in Single System LCH (SS-LCH), which is less aggressive than multisystem disease. However, there are no clear guidelines on which patients can be safely spared from systemic chemotherapy. Here, we propose a risk stratification framework based on disease quiescence as determined by clinical and biochemical features of inflammation, to identify low risk patients who may be potentially spared from chemotherapy through a conservative "wait-and-see" approach. Methods: Retrospective analysis in a single institution was conducted in children with SS-LCH, comparing features of inflammation and outcomes of those who received chemotherapy vs. those with quiescent disease, who were managed conservatively. Results: Of 44 children with SS-LCH, only patients without risk-organ involvement were considered for conservative management. A "wait-and-see" approach was adopted for patients with quiescent disease as defined by clinical and biochemical evidence of disease activity. Following 2 weeks of watchful observation, decisions were made to either start treatment or continue conservative management. Based on data collected at diagnosis, patients with quiescent disease had a lower mean platelet count 339 × 109/L (95%C.I: 285-393) vs. 482 × 109/L (95% C.I: 420-544) p < 0.01, a lower mean white cell count 9.3 × 109/L (95%C.I: 7.5-11.1) vs. 13.1 × 109/L (95%C.I: 11-15.2) p < 0.01 and lower Erythrocyte-Sedimentation-Rate (ESR) 8.2 mm/h (95%C.I: 5.4-11) vs. 53.7 mm/h (95%C.I: 11-96.3) p = 0.04, suggesting that these are potential biochemical markers of disease activity. Other features of disease quiescence noted were rapid progression, functional disability, presence of a skull depression rather a lump and the lack of fever. Conclusions: Further studies are required to validate our proposed framework to determine disease activity in SS-LCH. Within the limits of this current analysis, it appears that low-risk patients with clinically and biochemically quiescent SS-LCH, may potentially be spared from chemotherapy with good long-term outcomes.

Hepatitis B Virus Seropositivity Is a Poor Prognostic Factor of Pediatric Hepatocellular Carcinoma: a Population-Based Study in Hong Kong and Singapore.

BACKGROUND: Hepatocellular carcinoma (HCC) is a rare hepatic malignancy in children. Hepatitis B virus (HBV) infection is a key predisposing factor in endemic regions but its impact on outcome has not been studied. We aim to evaluate the prognostic implication of HBV seropositivity and role of cancer surveillance in children with HCC from East Asian populations with national HBV vaccination. METHODS: Review of population-based databases for patients (< 18 years old) diagnosed with HCC from 1993 to 2017 in two Southeast Asian regions with universal HBV vaccination (instituted since 1988 and 1987 in Hong Kong and Singapore, respectively). RESULTS: Thirty-nine patients were identified (Hong Kong, 28; Singapore, 11). Thirty were male; median age at diagnosis was 10.8 years (range, 0.98-16.6). Abdominal pain was the commonest presentation while five patients were diagnosed through surveillance for underlying condition. Alpha-fetoprotein was raised in 36 patients (mean, 500,598 ng/ml). Nineteen had bilobar involvement, among the patients in whom pretreatment extent of disease (PRETEXT) staging could retrospectively be assigned, 3 had stage I, 13 had stage II, 4 had stage III, and 11 had stage IV disease. Seventeen had distant metastasis. HBsAg was positive in 19 of 38 patients. Two patients had fibrolamellar HCC. Upfront management involved tumor resection in 16 (liver transplantation, 2), systemic chemotherapy in 21, interventional procedures in 6 [transarterial chemoembolization (TACE), 5, radiofrequency ablation (RFA), 1], and radiotherapy in 4 (selective internal radiation, 3, external beam radiation, 1). Five-year event-free survival (EFS) and overall survival (OS) were 15.4 ± 6.0 and 26.1 ± 7.2%, respectively. Patient's HBsAg positivity, metastatic disease and inability to undergo definitive resection represent poor prognostic factors in univariate and multivariable analyses. Patients diagnosed by surveillance had significantly better outcome. CONCLUSION: Pediatric HCC has poor outcome. HBV status remains relevant in the era of universal HBV vaccination. HBV carrier has inferior outcome and use of surveillance may mitigate disease course.

Intracerebral Flexner-Wintersteiner Rosette-Rich Tumor With Somatic RB1 Mutation: A CNS Embryonal Tumor With Retinoblastic Differentiation.

Diagnosis and classification of poorly differentiated tumors with primitive features of the central nervous system heavily relies on molecular and genetic findings of the tumors. Although RB1 gene mutation underlies the development of retinoblastoma and many other systemic cancers, RB1 gene mutation in a brain tumor is mainly limited to infiltrating gliomas. We describe what we believe to be a hitherto unreported case of sellar/suprasellar embryonal tumor with distinctive Flexner-Wintersteiner rosette formation, and somatic RB1 gene mutation in a 5-month-old infant. There were no molecular features associated with the embryonal tumor with multi-layered rosettes, and there were no histological or genetic features of a germ cell tumor. A follow up of 14 months duration showed good clinical response to VETOPEC regimen and no development of retinal disease. Our case shows an interesting association between RB1 mutation and Flexner-Wintersteiner rosettes in an embryonal tumor of the central nervous system and underscores the utility of large scale next generation sequencing in helping to identify the genetic aberrations that may help in clinical pathologic correlations of unusual or out-of-place histologic findings.

Acute pancreatitis during sickle cell vaso-occlusive painful crisis.

Sickle cell disease is characterized by chronic hemolytic anemia and vaso-occlusive painful crisis. The vascular occlusion in sickle cell disease is a complex process and accounts for the majority of the clinical manifestations of the disease. Abdominal pain is an important component of vaso-occlusive painful crisis and may mimic diseases such as acute appendicitis and cholecystitis. Acute pancreatitis is rarely included as a cause of abdominal pain in patients with sickle cell disease. When it occurs it may result form biliary obstruction, but in other instances it might be a consequence of microvessel occlusion causing ischemia. In this series we describe four cases of acute pancreatitis in patients with sickle cell disease apparently due to microvascular occlusion and ischemic injury to the pancreas. All patients responded to conservative management. Acute pancreatitis should be considered in the differential diagnosis of abdominal pain in patients with sickle cell disease.

An adolescent with ovarian osteosarcoma arising in a cystic teratoma.

A 14-year-old girl had an abdominal mass with the characteristics of an ovarian germ cell tumor on computed tomography scan. The mass, arising from the left ovary, was completely resected and found to be osteosarcoma arising from a mature cystic teratoma. A metastatic lesion in the abdomen did not respond to 2 courses of cisplatin, doxorubicin, ifosfamide, and high-dose methotrexate, and was resected. Seven months after completion of chemotherapy, there were simultaneous local recurrence and lung metastases. Previously, 10 cases of ovarian osteosarcoma have been reported in the literature: 5 were primary osteosarcoma of the ovary, 4 were associated with teratomas, and 1 was part of a malignant mixed mesodermal tumor of the ovary. Of the 10, there are only 2 long-term survivors, both of whom were treated with adjuvant chemotherapy following complete resection.

Prognostic variables in newly diagnosed childhood immune thrombocytopenia.

Immune thrombocytopenia (ITP) has a favorable prognosis in children. Only a small number of children go on to develop chronic ITP. However, at the time of diagnosis, it is not possible to predict the course of the disease. In order to determine prognostic factors that could predict the disease course at diagnosis, we retrospectively evaluated various clinical variables in 103 pediatric patients with newly diagnosed ITP at our institution from 1995 to 2001. Sixty-eight (66%) patients had a mean platelet volume (MPV) of <8 fL on admission. Of 72 patients who had a follow-up period of at least 6 months, 54 (75%) achieved a durable remission within 6 months and 18 (25%) developed chronic ITP. In univariate analysis, a low admission MPV (<8), history of viral prodrome, and a low admission platelet count (<10 x 10(9)/L) predicted for a favorable outcome. Age and sex did not correlate with remission. In multivariate analysis, a low admission MPV and a history of a viral prodrome were the only independent factors correlated with a durable CR. The adjusted odds ratio for achieving a durable remission was 8.9 (95% CI: 1.54-51.8) for history of a viral prodrome and 14 (95% CI: 2.52-83.3) for low admission MPV value. In conclusion, our study showed that a majority of the children with newly diagnosed ITP presented with a low MPV value. A history of viral illness and a low admission MPV were found to be independent prognostic variables that predicted for the achievement of a durable CR in childhood ITP.