National Centralization of Hirschsprung's Disease in Sweden:A Comparison of Preoperative Management and Outcomes.

BACKGROUND: Surgical treatment of Hirschsprung's disease (HSCR) in Sweden was centralized to two tertiary pediatric surgery centers 1st of July 2018. Although complex surgical care in adults seems to benefit from centralization there is little evidence to support centralization of pediatric surgical care. The aim of this study was to assess centralization of HSCR in Sweden, with special consideration to preoperative management and outcomes in this group of patients. METHODS: This study retrospectively analyzed data of patients with HSCR that had undergone or were planned to undergo pull-through at our center, from 1st of July 2013 to 30th of June 2023. Patients managed from 1st of July 2013 to 30th of June 2018 were compared with patients managed from 1st of July 2018 to 30th of June 2023 regarding diagnostic procedures, preoperative treatment, complications and time to definitive surgery. RESULTS: Thirty-six patients were managed during the first five-year period compared to 57 during the second period. There was an increased number of patients referred from other Swedish regions to our center following the centralization. Time from diagnosis to pull-through increased from 33 to 55 days after centralization. There were no significant differences in pre-operative management or complications, general or related to stoma. CONCLUSIONS: Despite increasing patient volumes and longer time from diagnosis to pull through, centralization of care for HSCR does not seem to change the preoperative management and risk of complications. With access to support from the specialist center, transanal irrigations remain a safe mode of at home management until surgery, regardless of distance to index hospital. LEVEL OF EVIDENCE: Level III.

Functional outcome and health-related quality of life in patients with sacrococcygeal teratoma - a Swedish multicenter study.

BACKGROUND/PURPOSE: The aims of this study were to evaluate bowel and urinary tract function, to identify predictors for dysfunctional outcome and to evaluate health-related quality-of life (QoL) in patients treated for sacrococcygeal teratomas (SCT). METHODS: Medical records of patients with SCT born between 1985 and 2015 treated at three Swedish pediatric surgical centers were reviewed. Questionnaires regarding urinary tract function, bowel function and QoL were sent to patients and parents. Different QoL instruments were used for the different age groups. RESULTS: Totally 85 patients were identified. Four patients died in the neonatal period. Forty-nine patients answered the questionnaires (60%). Median age at follow-up was 8.9 years (range 3.6-28.8). Bowel dysfunction was reported by 36% and urinary tract dysfunction by 46% of the patients. Univariate analysis revealed that urinary tract dysfunction correlated with gestational age (p = 0.018) and immature histology (p = 0.008), and bowel dysfunction correlated with gestational age (p = 0.016) and tumor size (p = 0.042). Low gestational age was an independent predictor for both urinary tract and bowel dysfunction. Good or very good QoL was reported by 56% of children aged 4-7 years, 90% of children aged 8-17 years and 67% of the adults. CONCLUSION: Although a considerable proportion of bowel and urinary tract dysfunction was found, the reported QoL was good in a majority of the patients with SCT. Low gestational age was found to be a predictor for bowel- and urinary tract dysfunction. LEVEL OF EVIDENCE: Level III.

Clinical response of the novel activating ALK-I1171T mutation in neuroblastoma to the ALK inhibitor ceritinib.

Tumors with anaplastic lymphoma kinase (ALK) fusion rearrangements, including non-small-cell lung cancer and anaplastic large cell lymphoma, are highly sensitive to ALK tyrosine kinase inhibitors (TKIs), underscoring the notion that such cancers are addicted to ALK activity. Although mutations in ALK are heavily implicated in childhood neuroblastoma, response to the ALK TKI crizotinib has been disappointing. Embryonal tumors in patients with DNA repair defects such as Fanconi anemia (FA) often have a poor prognosis, because of lack of therapeutic options. Here we report a child with underlying FA and ALK mutant high-risk neuroblastoma responding strongly to precision therapy with the ALK TKI ceritinib. Conventional chemotherapy treatment caused severe, life-threatening toxicity. Genomic analysis of the initial biopsy identified germline FANCA mutations as well as a novel ALK-I1171T variant. ALK-I1171T generates a potent gain-of-function mutant, as measured in PC12 cell neurite outgrowth and NIH3T3 transformation. Pharmacological inhibition profiling of ALK-I1171T in response to various ALK TKIs identified an 11-fold improved inhibition of ALK-I1171T with ceritinib when compared with crizotinib. Immunoaffinity-coupled LC-MS/MS phosphoproteomics analysis indicated a decrease in ALK signaling in response to ceritinib. Ceritinib was therefore selected for treatment in this child. Monotherapy with ceritinib was well tolerated and resulted in normalized catecholamine markers and tumor shrinkage. After 7.5 mo treatment, the residual primary tumor shrunk, was surgically removed, and exhibited hallmarks of differentiation together with reduced Ki67 levels. Clinical follow-up after 21 mo treatment revealed complete clinical remission including all metastatic sites. Therefore, ceritinib presents a viable therapeutic option for ALK-positive neuroblastoma.

Pancreatectomies for pancreatic neoplasms in pediatric and adolescent age: A single institution experience.

BACKGROUND: There are very few data in the current literature regarding the short- and long-term outcome of surgery for pediatric pancreatic tumors (PPT). No data are available on the impact of pancreatic surgery on the children's growth. METHODS: This is a retrospective cohort study on a consecutive series of pediatric/adolescent patients who underwent pediatric surgery at Karolinska University Hospital from January 2005 to July 2017. RESULTS: Overall 14 pancreatic operations were performed in 13 patients. The median age was 11.4 years (range 3-15). Six pancreaticoduodenectomies (42.8%), 5 distal pancreatectomies (35.7%), and 3 enucleations (21.5%) were performed. The final histology revealed a solid pseudopapillary tumor in 9 cases (69.2%), neuroblastoma in 1 (7.7%), ganglioneuroma in 1 (7.7%), pancreatoblastoma in 1 (7.7%), and insulinoma in 1 (7.7%). Overall, 3 patients developed post-operative complications (23%). There was no peri-operative mortality. All patients are alive after a median follow-up time of 80 months. Exocrine insufficiency was detected post-operatively in 4 patients (30.7%) Endocrine insufficiency requiring insulin treatment developed in one patient (7.7%). No significant impact on growth was detected in any of the patients after pancreatic resection. CONCLUSIONS: In our series, surgery performed for PPTs seems to be safe and effective. The effect of pancreatic surgery on children's growth does not seem to be significant.

Mutation screening and array comparative genomic hybridization using a 180K oligonucleotide array in VACTERL association.

In order to identify genetic causes of VACTERL association (V vertebral defects, A anorectal malformations, C cardiac defects, T tracheoesofageal fistula, E esophageal atresia, R renal anomalies, L limb deformities), we have collected DNA samples from 20 patients diagnosed with VACTERL or with a VACTERL-like phenotype as well as samples from 19 aborted fetal cases with VACTERL. To investigate the importance of gene dose alterations in the genetic etiology of VACTERL association we have performed a systematic analysis of this cohort using a 180K array comparative genomic hybridization (array-CGH) platform. In addition, to further clarify the significance of PCSK5, HOXD13 and CHD7 genes in the VACTERL phenotype, mutation screening has been performed. We identified pathogenic gene dose imbalances in two fetal cases; a hemizygous deletion of the FANCB gene and a (9;18)(p24;q12) unbalanced translocation. In addition, one pathogenic mutation in CHD7 was detected, while no apparent disease-causing mutations were found in HOXD13 or PCSK5. Our study shows that although large gene dose alterations do not seem to be a common cause in VACTERL association, array-CGH is still important in clinical diagnostics to identify disease cause in individual cases.

Laparoscopic-assisted pull-through for Hirschsprung's disease, a prospective repeated evaluation of functional outcome.

AIM OF THE STUDY: To evaluate the functional outcome of laparoscopic-assisted endorectal pull-through (LAP) for Hirschsprung's disease (HSCR) over time. METHODS: Thirty-five children with HSCR underwent laparoscopic-assisted pull-through at our institution between 1998 and 2009. The diagnosis was histologically confirmed in all cases. Clinical data was extracted from the case records. A prospective assessment of the functional outcome was performed in 2009 and 2012. Exclusion criteria were a follow-up of less than 6 months after treatment (1 case) and total colonic aganglionosis (1 case). An independent examiner, not involved in the clinical care of the patients, performed interviews using a semi-structured questionnaire. Four patients could not be traced for the first interview. Two cases were lost for the second interview. Altogether twenty-seven patients completed the study. Data from the two interviews were compared. The regional ethical review board approved the study. MAIN RESULTS: The median patient age was 4 years old (range 2-16) at the time of the first interview and 7 years old (range 5-19) at the time of the second interview . There were 23 males and 4 females in the study group. The median age at laparoscopic-assisted pull-through was 104 days old (range 29 days-8 years). In the first interview 11 patients reported constipation, 18 patients reported soiling more frequently than once per week when they had loose stools and 16 patients when they had solid stools. Laxatives or irrigations were used by 13 of the patients. In the second interview 4 patients reported constipation, 16 patients reported soiling when they had loose stools and 15 patients reported soiling when they had solid stools. Eight patients used laxatives or irrigations. The decrease in constipation was statistically significant (p=0,023). CONCLUSIONS: Our study shows a statistically significant reduction of constipation over time. There is a high risk of incontinence after laparoscopic-assisted pull-through, with few signs of short-term improvement.

Supraumbilical incision with U-u umbilicoplasty for congenital duodenal atresia: the Stockholm experience.

BACKGROUND: Minimizing scars has become a major concern in pediatric surgery. Since Tan and Bianchi introduced the minimally invasive umbilical incision for Ramstedt's pyloromyotomy, their technique has been adopted for a variety of neonatal abdominal conditions. The aim of this study was to evaluate a modification of the skin incision. MATERIAL AND METHODS: We have modified Bianchi's original technique to access the abdomen through the linea alba by introducing a novel U-to-u umbilicoplasty and compare the results with the traditional transverse incision. This new approach improves the abdominal access and is easy to perform. RESULTS: The operating time with the U-to-u umbilicoplasty is not longer than in standard transverse laparotomy, the access to the abdomen is more than adequate, the incidence of postoperative complications is similar and the cosmetic results are excellent. CONCLUSIONS: We conclude that the umbilical approach with this novel U-to-u umbilicoplasty to treat congenital duodenal obstruction in the newborn is a safe and effective method and a good alternative to the standard transverse laparotomy approach.

Mutation analysis of the motor neuron and pancreas homeobox 1 (MNX1, former HLXB9) gene in Swedish patients with Currarino syndrome.

BACKGROUND: Currarino syndrome (CS) is a triad consisting of partial sacral agenesis, presacral mass, and anorectal malformations, typically anal stenosis but the phenotype varies. The main cause of this monogenic disorder is mutations in the motor neuron and pancreas homeobox 1 gene. We describe the clinical and genetic findings in 4 unrelated Swedish cases with CS and their relatives. METHODS: We performed mutation analysis of the motor neuron and pancreas homeobox 1 gene in 4 cases with CS by DNA sequence analysis as well as multiplex ligation-dependent probe amplification. In addition, array comparative genome hybridization was performed in 2 cases. Including relatives, totally, 14 individuals were analyzed. RESULTS: We found 2 previously described mutations, 1 de novo nonsense mutation (p.Gln212X) and 1 maternally inherited frameshift mutation (p.Pro18ProfsX38). In the family with the frameshift mutation, we also detected the same maternally inherited mutation in 3 of the proband's 4 brothers, who displayed varying symptoms. All mutation carriers had presacral tumors, although 2 were asymptomatic. CONCLUSION: Our findings emphasize the need for genetic counseling and mutation analysis in patients with CS to detect tumors early. It shows the importance of evaluation of the sacrum and the presacral region in patients with anal stenosis with or without funnel anus. Family members of index cases should be considered for evaluation even if they are asymptomatic.

Nerve growth factor receptor immunohistochemistry has a limited additional value to diagnose Hirschsprung's disease.

PURPOSE: The diagnosis of Hirschsprung's disease (HSCR) is based on the histopathological evaluation of rectal suction biopsies (RSB), using haematoxylin and eosin (H&E) stains and acetylcholinesterase (AChE) histochemistry. The use of different immunohistochemical markers, such as nerve growth factor receptor (NGFR), has been suggested to facilitate the diagnosis of HSCR. The aim of this study was to evaluate the addition of NGFR immunohistochemistry to diagnose HSCR. METHODS: RSB from 23 HSCR patients and 16 patients investigated for, but not diagnosed with, HSCR were retrospectively reviewed. The histopathology report supported or did not support the diagnosis of HSCR. RESULTS: In patients with HSCR, the primary biopsies confirmed the diagnosis in 21 of 23 cases with H&E staining, in 16 of 23 cases with AChE histochemistry, and in 8 of 23 cases with NGFR immunohistochemistry. Due to inadequate biopsies or equivocal interpretation, the biopsies were repeated in seven of the patients with HSCR and two patients underwent biopsies a third time. In the 16 patients investigated for but not diagnosed with HSCR, the three tests were normal in all cases. CONCLUSION: We conclude that NGFR immunohistochemistry has limited additional value to diagnose HSCR.

PHOX2B genotype allows for prediction of tumor risk in congenital central hypoventilation syndrome.

The Phox2b gene is necessary for autonomic nervous-system development. Phox2b-/- mice die in utero with absent autonomic nervous system circuits, since autonomic nervous system neurons either fail to form or degenerate. We first identified the Phox2b human ortholog, PHOX2B, as the gene underlying congenital central hypoventilation syndrome (CCHS, or Ondine curse), with an autosomal dominant mode of inheritance and de novo mutation at the first generation. We have subsequently shown that heterozygous mutations of PHOX2B may account for several combined or isolated disorders of autonomic nervous-system development--namely, tumors of the sympathetic nervous system (TSNS), such as neuroblastoma and late-onset central hypoventilation syndrome. Here, we report the clinical and molecular assessments of a cohort of 188 probands with CCHS, either isolated or associated with Hirschsprung disease and/or TSNS. The mutation-detection rate was 92.6% (174/188) in our series, and the most prevalent mutation was an in-frame duplication leading to an expansion of +5 to +13 alanines in the 20-alanine stretch at the carboxy terminal of the protein. Such findings suggest PHOX2B mutation screening as a simple and reliable tool for the diagnosis of CCHS, independent of the clinically variable phenotype. In addition, somatic mosaicism was detected in 4.5% of parents. Most interestingly, analysis of genotype-phenotype interactions strongly supports the contention that patients with CCHS who develop malignant TSNS will harbor either a missense or a frameshift heterozygous mutation of the PHOX2B gene. These data further highlight the link between congenital malformations and tumor predisposition when a master gene in development is mutated.