A Report of a Case With Pediatric Ovarian Steroid Cell Tumor, Not Otherwise Specified, Found With Precocious Puberty.

A 4-year-old girl was admitted to our hospital because of precocious puberty. Radiologic findings revealed a fist-sized solid tumor in the left ovary without ascites, peritoneal dissemination, and distant metastasis. The patient underwent left salpingo-oophorectomy without spillage. The size of the excised tumor was 10.0×9.0×4.8 cm. On pathologic examination, the tumor was diagnosed as an ovarian steroid cell tumor, not otherwise specified. In the present case, although the diameter of the tumor (>7 cm) and three mitoses per 10 high-power fields represented some potential for malignancy, we opted for careful observation without chemotherapy as the tumor was of clinical stage Ia.

Neonatal outcomes of congenital diaphragmatic hernia in full term versus early term deliveries: A systematic review and meta-analysis.

This systematic review and meta-analysis aimed to review the optimal timing of delivery at term for neonates with prenatally diagnosed congenital diaphragmatic hernia (CDH). We reviewed the literature up to December 19, 2022 using MEDLINE and the Cochrane Library databases. The inclusion criteria were original articles, comparative studies of CDH neonates delivered at an early term (37-38 weeks of gestation) and at full term (39 weeks of gestation or later), and comparative studies investigating outcomes of CDH neonates. Six studies met the inclusion criteria, including 985 neonates delivered at an early term and 629 delivered at full term. The cumulative rate of survival to discharge showed no significant difference between CDH neonates delivered at an early term (395/515; 76.7%) or at full term (345/467; 73.9%) (risk ratio [RR] 1.01; 95% confidence interval [CI], 0.89-1.16; p = 0.85). Furthermore, the number of neonates requiring oxygen therapy at discharge was not significantly different between CDH neonates delivered at an early term (32/370; 8.6%) and at full term (14/154; 9.1%) (RR, 0.99; 95% CI, 0.36-2.70; p = 0.99). Therefore, the optimal timing of delivery at term for neonates with CDH remains unclear.

Analysis of factors associated with undescended testis in patients with congenital diaphragmatic hernia.

PURPOSE: This study aimed to investigate the incidence and clinical factors associated with undescended testes (UDT) in patients with congenital diaphragmatic hernia (CDH). METHODS: We retrospectively reviewed the incidence of UDT in male neonates admitted to our institution and underwent surgery for CDH between January 2006 and December 2022. Patients were divided into two groups based on the presence or absence of UDT, and risk factors for UDT were compared between the two groups. RESULTS: Among the 66 male neonates with CDH, 16 (24.2%) developed UDT. Patients with UDT had a significantly smaller gestational age (p = 0.026), lower birth weight (p = 0.042), and lower Apgar score at 1 min (p = 0.016) than those without UDT. They had a significantly higher incidence of large diaphragmatic defects (p = 0.005), received more patch closures (p = 0.020), had a longer mechanical ventilation period (p = 0.034), and longer hospital stay (p = 0.028). Multiple logistic regression analysis revealed that large diaphragmatic defect was an independent risk factor for UDT (adjusted odds ratio of 3.87). CONCLUSION: CDH and UDT are strongly correlated. In patients with CDH, the incidence of UDT was related not only to patients' prematurity but also to the large diaphragmatic defect. Large diaphragmatic defect is an independent risk factor for UDT in patients with CDH.

Feasibility and safety of laparoscopic tumor resection in children with abdominal neuroblastomas.

PURPOSE: This study aimed to evaluate the feasibility and safety of laparoscopic resection of abdominal neuroblastoma by comparing operative and long-term oncologic outcomes between open and laparoscopic surgeries. METHODS: This single-center retrospective study included patients who underwent laparoscopic tumor resection, between January 2000 and June 2021, with a maximum tumor diameter of ≤ 60 mm and without image-defined risk factors (IDRFs) at surgery. Data from 35 abdominal neuroblastoma resections were reviewed and compared between the laparotomy and laparoscopic groups. RESULTS: Nineteen patients underwent laparotomy and 16 had laparoscopic tumor resection. All laparoscopic surgeries achieved complete resection without conversion to open surgery. Median blood loss was significantly lower in the laparoscopic group (0.6 mL/kg) than in the laparotomy group (8.4 mL/kg) (P < 0.0001). There were two locoregional recurrences in the laparoscopic group and two metastatic recurrences in the laparotomy group. Five-year overall survival was 93.8% in both groups. CONCLUSION: Laparoscopic resection of abdominal neuroblastomas in children is a feasible and safe procedure for tumors ≤ 60 mm in diameter with no IDRFs at surgery, with long-term outcomes equivalent to laparotomy.

Risk factors for and developmental relation of delayed oral nutrition in infants with congenital diaphragmatic hernia.

PURPOSE: To identify risk factors for delayed oral nutrition in infants with a congenital diaphragmatic hernia (CDH) and its impact on developmental delay at 18 months of age. METHODS: This retrospective single-center cohort study compared the clinical parameters in patients with isolated CDH born and treated at our hospital between 2006 and 2020. We evaluated clinical features significantly related to delayed oral nutrition (defined as taking ≥ 30 days from weaning from mechanical ventilation to weaning from tube feeding). RESULTS: Twenty-six of the 80 cases had delayed oral nutrition. Univariate analyses showed significant differences. Multivariate analyses were performed on the three items of preterm delivery, defect size (over 50% to nearly entire defect), and ventilation for ≥ 9 days. We identified the latter two items as independent risk factors. The adjusted odds ratios were 4.65 (95% confidence interval, 1.27-7.03) and 6.02 (1.65-21.90), respectively. Delayed oral nutrition was related to a significantly higher probability of developmental delay at 18 months (crude odds ratio 4.16, 1.19-14.5). CONCLUSION: In patients with CDH, a large defect and ventilatory management over 9 days are independent risk factors for delayed oral nutrition, which is a potent predictor of developmental delay that requires active developmental care.

Beta-human chorionic gonadotropin-producing neuroblastoma: an unrecognized cause of gonadotropin-independent precocious puberty.

The pathogenesis of gonadotropin-independent precocious puberty (PP) includes both congenital and acquired forms, the latter of which may be associated with neoplasms, such as sex-steroid hormone-producing tumors. Beta-human chorionic gonadotropin (ß-hCG)-producing tumors also cause gonadotropin-independent PP by stimulating the production of testosterone in Leydig cells. Germ cell tumors and hepatoblastoma both produce ß-hCG; however, there is limited evidence to show that gonadotropin-independent PP is caused by other ß-hCG-producing tumors. We herein report the first case of ß-hCG-producing neuroblastoma associated with the development of gonadotropin-independent PP. A 2-year-old boy presented with an increased penile length, enlargement of the testes, pigmentation of the external genitalia, and growth acceleration. Imaging, blood, and urinary examinations revealed the presence of neuroblastoma in the right adrenal region. Decreased levels of luteinizing hormone and follicle-stimulating hormone with an increased testosterone level were indicative of gonadotropin-independent PP. Since serum ß-hCG was elevated, ß-hCG-producing neuroblastoma was suspected. Histological findings of the resected tumor were compatible with neuroblastoma. An immunohistochemical analysis using serial sections revealed staining for ß-hCG in synaptophysin-positive cells. Furthermore, immunofluorescence showed the co-staining of ß-hCG with neuron-specific enolase. These results suggested that ß-hCG was produced by tumor cells. Surgical removal of the tumor promptly normalized serum ß-hCG and testosterone levels. In conclusion, we propose the addition of neuroblastoma to the list of differential diagnoses of gonadotropin-independent PP with ß-hCG positivity in serum that includes germ cell tumors and hepatoblastoma.

Clinical factors related to undescended testis in infants with gastroschisis.

BACKGROUND: Recent studies have reported the high incidence of undescended testis (UDT) in patients with gastroschisis. Although various mechanical, hormonal, and genetic theories have been postulated to describe testicular descent, the mechanism contributing to this condition remains controversial. We aimed to investigate the incidence and risk factors of UDT in infants with gastroschisis. METHODS: Male neonates who underwent surgery for gastroschisis between January 1982 and December 2019 were enrolled. Data were analyzed regarding the prevalence of UDT, including spontaneous testicular descent and the necessity of orchidopexy. Patients were grouped into those with or without UDT to identify the risk factors for UDT. RESULTS: Among 38 patients with gastroschisis, six (15.8%) developed UDT. There were no significant differences in gestational age or birthweight between patients with and without UDT. The patients with UDT had a significantly larger defect size than those without UDT (P = 0.037). In addition, the timing of abdominal closure was significantly later in patients with UDT than in those without UDT (P = 0.004). None of the patients with UDT exhibited spontaneous testicular descent requiring subsequent orchidopexy. CONCLUSIONS: Patients with gastroschisis had a high prevalence of UDT. In gastroschisis, the incidence of UDT was related to the defect size and the timing of abdominal wall closure, indicating that an insufficient increase in intra-abdominal pressure during the fetal period may affect the development of UDT.

Risk of carcinogenesis in the biliary epithelium of children with congenital biliary dilatation through epigenetic and genetic regulation.

PURPOSES: Congenital biliary dilatation (CBD), defined as pancreaticobiliary maljunction (PBM) with biliary dilatation, is a high risk factor for biliary tract cancer (BTC). KRAS and p53 mutations reportedly affect this process, but the mechanisms are unclear, as is the likelihood of BTC later in life in children with CBD. We investigated potential carcinogenetic pathways in children with CBD compared with adults. METHODS: The subjects of this study were nine children with CBD and 13 adults with PBM (10 dilated, 3 non-dilated) without BTC who underwent extrahepatic bile duct resections, as well as four control patients who underwent pancreaticoduodenectomy for non-biliary cancer. We evaluated expressions of Ki-67, KRAS, p53, histone deacetylase (HDAC) and activation-induced cytidine deaminase (AID) in the biliary tract epithelium immunohistochemically. RESULTS: The Ki-67 labeling index (LI) and expressions of KRAS, p53, HDAC, and AID in the gallbladder epithelium were significantly higher or tended to be higher in both the children with CBD and the adults with PBM than in the controls. CONCLUSIONS: BTC may develop later in children with CBD and in adults with PBM, via HDAC and AID expression and through epigenetic and genetic regulation.

Factors associated with neonatal surgical site infection after abdominal surgery.

PURPOSE: To assess the risk factors for surgical site infections (SSIs) post-abdominal surgery in neonates. METHODS: A retrospective, single-center cohort study was conducted using patient data from 2009 to 2018. Patient characteristics and several variables were analyzed to identify independent risk factors for SSI. RESULTS: SSI occurred in 39/406 procedures (9.6%). Univariate analysis showed that the incidence of SSI was significantly higher in patients who had undergone multiple surgical procedures (P = 0.032), prolonged operations (P = 0.016), long-term hospitalization (P < 0.001), long-term antibiotic administration (P < 0.001), with methicillin-resistant Staphylococcus aureus (MRSA) colonization (P = 0.044), contaminated/dirty wounds (P < 0.001), and American Society of Anesthesiologists physical status of 3 or 4 (P = 0.021). Multivariate analysis identified prolonged operations [odds ratio (OR): 2.91 (1.21-8.01)] and contaminated/dirty wounds [OR: 5.42 (2.41-12.1)] as independent risk factors. Patients with SSI had a higher incidence of MRSA colonization (27.8% vs. 14.8%, P = 0.044), longer antibiotic administration (24 days vs. 8 days, P = 0.049), and longer hospitalization times (98 days vs. 43 days, P = 0.007) than those without SSIs. CONCLUSIONS: Long operations exceeding 100 min and surgical procedures with contaminated/dirty wounds are independent risk factors for neonatal SSIs after abdominal surgery. SSIs were related to MRSA colonization during hospitalization, long-term antibiotic administration, and long-term hospitalization.

Persistent cloaca with fetal ascites: clinical features and perinatal management.

PURPOSE: Fetuses with persistent cloaca are known to develop urine or meconium backflow into the abdominal cavity caused by obstruction of the common channel, thus leading to fetal peritonitis with fetal ascites. We analyzed the impact of prenatal fetal ascites on postnatal clinical features and management. METHODS: This retrospective single-center cohort study was conducted to compare the perinatal parameters of patients with isolated persistent cloaca who were born and treated at our hospital between 1991 and 2021. The clinical features and management of those with and without fetal ascites were compared. RESULTS: Among the 17 eligible patients, fetal ascites were recognized in seven. The occurrence of fetal ascites was significantly related to preterm birth, higher birth weight z-score, birth via emergency cesarean delivery, low Apgar scores at 1 min and 5 min, higher C-reactive protein levels at birth, longer duration of oxygen administration, the need for a urinary drainage catheter at initial discharge, and shorter neonatal hospital stays. CONCLUSIONS: The postnatal management of patients with persistent cloaca with fetal ascites differed significantly from that of patients without fetal ascites. For patients with unexplained fetal ascites, magnetic resonance imaging may be helpful for determining the definite diagnosis of persistent cloaca.

A predictive scoring system for small diaphragmatic defects in infants with congenital diaphragmatic hernia.

PURPOSE: To develop a predictive score for small diaphragmatic defects in infants with congenital diaphragmatic hernia (CDH) for determining thoracoscopic surgery indication. METHODS: The Japanese CDH Study Group cohort was randomly divided into derivation (n = 397) and validation (n = 396) datasets. Using logistic regression, a prediction model and weighted scoring system for small diaphragmatic defects were created from derivation dataset and validated with validation dataset. RESULTS: Six weighted variables were selected: no hydramnios, 1 point; 1 min Apgar score of 5-10, 1 point; apex type of the lung (left lung is detected radiographically in apex area), 1 point; oxygenation index < 8, 1 point; abdominal nasogastric tube (tip of the nasogastric tube is detected radiographically in the abdominal area), 2 points; no right-to-left flow of ductus arteriosus, 1 point. In validation dataset, rates of small diaphragmatic defects for Possible (0-3 points), Probable (4-5 points), and Definite (6-7 points) groups were 36%, 81%, and 94%, respectively (p < 0.001). Additionally, sensitivity, specificity, positive predictive value, and C statistics were 0.78, 0.79, 0.88, 0.76, and 0.45, 0.94, 0.94, 0.70 for Probable and Definite groups, respectively. CONCLUSION: Our scoring system effectively predicted small diaphragmatic defects in infants with CDH.

Prenatal predictors of mortality in fetuses with congenital diaphragmatic hernia: a systematic review and meta-analysis.

PURPOSE: This study aimed to evaluate prenatal predictors of mortality in fetuses with congenital diaphragmatic hernia (CDH). METHODS: A systematic literature search was performed to identify relevant observational studies that evaluated the ability of lung-to-head ratio (LHR), observed-to-expected LHR (o/e-LHR), observed-to-expected total fetal lung volume (o/e-TFLV), lung-to-thorax transverse area ratio (L/T ratio), intrathoracic herniation of the liver and the stomach, and side of diaphragmatic hernia, using a threshold for the prediction of mortality in fetuses with CDH. Study quality was assessed using the QUADAS-2 tool. Hierarchical summary receiver operating characteristic curves were constructed. RESULTS: A total of 50 articles were included in this meta-analysis. The QUADAS-2 tool identified a high risk of bias in more than one domain scored in all parameters. Among those parameters, the diagnostic odds ratio of mortality with o/e-LHR < 25%, o/e-TFLV < 25%, and L/T ratio < 0.08 were 11.98 [95% confidence interval (CI) 4.65-30.89], 11.14 (95% CI 5.19-23.89), and 10.28 (95% CI 3.38-31.31), respectively. The predictive values for mortality were similar between the presence of liver herniation and retrocardiac fetal stomach position. CONCLUSIONS: This systematic review suggests that o/e-LHR, o/e-TFLV, and L/T ratio are equally good predictors of neonatal mortality in fetuses with isolated CDH.

The efficacy of the postnatal nasogastric tube position as a prognostic marker of left-sided isolated congenital diaphragmatic hernia.

PURPOSE: The prenatal diagnosis of the stomach position in congenital diaphragmatic hernia (CDH) has been a reliable prognostic factor, but few studies have focused on the postnatal position. We therefore evaluated the significance of the nasogastric (NG) tube position just after birth. METHODS: The Japanese CDH Study Group database enrolled 1037 CDH neonates over 15 years. In our multicenter retrospective study, 464 cases of left-sided isolated CDH with prenatal diagnoses were divided into two groups: NG tube below the diaphragm (BD; n = 190) or above the diaphragm (AD; n = 274). The primary outcome was the 90-day survival rate, and the secondary outcomes were mechanical ventilation duration, hospitalization duration, and recurrence rate. RESULTS: The BD group had a significantly higher 90-day survival rate (98.4 vs. 89.4%, p < 0.001), shorter mechanical ventilation (11 vs. 19 days, p < 0.001), shorter hospitalization (38 vs. 59 days, p < 0.001), and lower recurrence rate (p = 0.002) than the AD group. A multivariate analysis showed that BD (adjusted odds ratio, 3.68; 95% confidence interval 1.02-13.30) was a favorable prognostic factor for the 90-day survival. CONCLUSION: The assessment of the NG tube position revealed it to be a reliable prognostic factor of left-sided isolated CDH. Therefore, it should be included as a routine assessment.

A Rare Case of Immature Sacrococcygeal Teratoma With Lymph Node Metastasis in a Neonate.

This is the first report of an immature sacrococcygeal teratoma with inguinal lymph node metastasis, providing the histologic transformation of an immature teratoma in association with chemotherapy. Incomplete tumor resection with coccygectomy was performed, and the histopathologic diagnosis was a grade 3 immature teratoma. Following the initial surgery, the residual tumors enlarged and the tumors metastasized to the inguinal lymph node, demonstrating immature teratoma without yolk sac tumor components. Although the tumor markers normalized after chemotherapy, the residual tumors had enlarged significantly. Therefore, a complete resection of the residual tumors was performed, and they were found to be mature teratomas.

Clinical guidelines for the treatment of congenital diaphragmatic hernia.

Congenital diaphragmatic hernia (CDH) is a birth defect of the diaphragm in which abdominal organs herniate through the defect into the thoracic cavity. The main pathophysiology is respiratory distress and persistent pulmonary hypertension because of pulmonary hypoplasia caused by compression of the elevated organs. Recent progress in prenatal diagnosis and postnatal care has led to an increase in the survival rate of patients with CDH. However, some survivors experience mid- and long-term disabilities and complications requiring treatment and follow-up. In recent years, the establishment of clinical practice guidelines has been promoted in various medical fields to offer optimal medical care, with the goal of improvement of the disease' outcomes, thereby reducing medical costs, etc. Thus, to provide adequate medical care through standardization of treatment and elimination of disparities in clinical management, and to improve the survival rate and mid- and long-term prognosis of patients with CDH, we present here the clinical practice guidelines for postnatal management of CDH. These are based on the principles of evidence-based medicine using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. The recommendations are based on evidence and were determined after considering the balance among benefits and harm, patient and society preferences, and medical resources available for postnatal CDH treatment.

Thoracoscopic repair of congenital diaphragmatic hernia in neonates: findings of a multicenter study in Japan.

PURPOSE: We compared the efficacy of thoracoscopic repair (TR) with that of open repair (OR) for neonatal congenital diaphragmatic hernia (CDH). METHODS: The subjects of this multicenter retrospective cohort study were 524 infants with left-sided isolated CDH, diagnosed prenatally, and treated at one of 15 participating hospitals in Japan between 2006 and 2018. The outcomes of infants who underwent TR and those who underwent OR were compared, applying propensity score matching. RESULTS: During the study period, 57 infants underwent TR and 467 underwent OR. Ten of the infants who underwent TR required conversion to OR for technical difficulties and these patients were excluded from the analysis. The survival rate at 180 days was similar in both groups (TR 98%; OR 93%). Recurrence developed after TR in 3 patients and after OR in 15 patients (TR 7%, OR 3%, p = 0.40). The propensity score was calculated using the following factors related to relevance of the surgical procedure: prematurity (p = 0.1), liver up (p < 0.01), stomach position (p < 0.01), and RL shunt (p = 0.045). After propensity score matching, the multivariate analysis adjusted for severity classification and age at surgical treatment revealed a significantly shorter hospital stay (odds ratio 0.50) and a lower incidence of chronic lung disease (odds ratio 0.39) in the TR group than in the OR group. CONCLUSIONS: TR can be performed safely for selected CDH neonates with potentially better outcomes than OR.

Optimal timing of surgery in infants with prenatally diagnosed isolated left-sided congenital diaphragmatic hernia: a multicenter, cohort study in Japan.

PURPOSE: To date, there is no compelling evidence of the optimal timing of surgery for congenital diaphragmatic hernia (CDH). This study aimed to establish the optimal timing of surgery in neonates with isolated left-sided CDH. METHODS: This multicenter cohort study enrolled 276 patients with isolated left-sided CDH at 15 institutions. Based on the timing of surgery, the patients were classified into four groups [< 24 h (G1), 24-47 h (G2), 48-71 h (G3), and ≥ 72 h (G4)]. The clinical outcomes were compared among the groups using a logistic regression model, after adjusting for potential confounders, such as disease severity. RESULTS: Multivariate analyses showed that G2 also had a lower mortality rate than the other groups. In mild and severe cases, there were no significant differences in mortality across the four groups. In moderate cases, G2 resulted in significantly increased survival rates, compared with G1. CONCLUSION: The study results suggest that surgery within 24 h of birth is not recommended for patients with moderate severity CDH, that there is no benefit in the delay of surgery for more than 72 h in mild severity CDH patients, and that there is no definite optimal time to perform surgery in severe cases of CDH.

The risk factors for cholestasis in patients with duodenal atresia in a single institutional cohort.

PURPOSE: The etiology of cholestasis in neonates is associated with several factors including gastrointestinal disease and surgery. We aimed to identify the potential risk factors for perioperative cholestasis in patients with duodenal atresia and determine specific cutoff values for the risk factors. METHODS: This retrospective cohort study included 76 neonates diagnosed with duodenal atresia surgically treated during the neonatal period at our institution between January 1990 and March 2017. The neonates were categorized into two groups: those with and without cholestasis. Univariate and multivariate analyses were performed to identify the possible risk factors for cholestasis. RESULTS: Among the 76 neonates with duodenal atresia, 21 (27%) developed cholestasis. The duration of total parenteral nutrition was identified as a risk factor in univariate analysis; however, it was not an independent risk factor for cholestasis. Gestational age and highest C-reactive protein (CRP) values were independent risk factors, with adjusted odds ratios of 0.53 and 1.25, respectively. To predict the occurrence of cholestasis, the cutoff value for gestational age was 35.0 weeks, and highest CRP value was 2.4 mg/dL. CONCLUSIONS: The occurrence of cholestasis in patients with duodenal atresia was associated with preterm delivery and severity of the inflammatory response during the perioperative period.

Computed tomography-guided marking using a dye-staining method for preoperative localization of tiny pulmonary lesions in children.

PURPOSE: It is important to confirm the existence of pulmonary metastases in pediatric patients with malignancies. Therefore, we aimed to investigate if computed tomography CT-guided marking is a feasible and safe method for the identification and resection of tiny pulmonary lesions in pediatric cancer patients. METHODS: We retrospectively reviewed the medical records of pediatric cancer patients who underwent CT-guided marking procedures in our institutions between Jan 2011 and Apr 2020. After 2015, these procedures were combined with an indocyanine green (ICG) navigation-guided surgery for hepatoblastoma cases. RESULTS: We targeted a total of 22 nodules in 12 patients. Of these, marking was successful in 18 (81.8%) nodules, 10 of which contained viable malignant cells. Complications caused by the marking procedures included mild pneumothorax and mild atelectasis in two patients, respectively. Of the eight resected nodules in patients with hepatoblastoma, four were ICG-positive and contained viable malignant cells. Two additional ICG-positive nodules, which were unidentified before surgery, were observed intraoperatively. CONCLUSION: CT-guided marking is a feasible and safe method that can be used to identify and resect tiny pulmonary lesions in pediatric cancer patients. An ICG navigation-guided surgery is useful when combined with CT-guided marking, particularly in hepatoblastoma cases.

Results of mass screening for neuroblastoma in 18-month-old infants in Osaka area, Japan.

PURPOSE: In 2004, the Japanese government halted nationwide mass screening for neuroblastoma in 6-month-old infants as it led to overdiagnosis of localized tumors with favorable prognoses and failed to reduce neuroblastoma-related mortality. However, a new mass screening program for neuroblastoma in 18-month-old infants (18MS) was conducted in the Osaka prefecture. We assessed the efficacy of the 18MS in screening unfavorable cases. METHODS: Public health centers in Osaka prefecture, excluding the Osaka city area, provided test kits to the guardians of infants who received a check-up at 18 months of age between 2004 and 2017. For patients whose standardized urinary levels of vanillylmandelic acid or homovanillic acid exceeded the threshold, they were further examined and treated in two specific hospitals Osaka University Hospital and Osaka Women's and Children's Hospital. Screening-positive patients with and without neuroblastoma were retrospectively reviewed. RESULTS: Among 142,423 children screened during the 18MS, 85 tested positive, and 14 were diagnosed with neuroblastoma. Twelve patients were classified as very low risk, while 2 were classified as high risk, based on the International Neuroblastoma Risk Group risk classification. CONCLUSION: The 18MS did not screen unfavorable cases with neuroblastoma efficiently, although few participants benefited from it.