An ultrasound-guided supraclavicular approach for tunneled central venous catheter insertion can be safely performed by junior residents.

PURPOSE: Ultrasound-guided supraclavicular catheterization (UGSC) of the brachiocephalic vein (BCV) for long-term tunneled central venous catheter (tCVC) insertion may be safer than the internal jugular vein approach due to its superior field of view. We examined the clinical outcomes of tCVC insertions performed by junior residents through UGSC of the BCV. PATIENTS AND METHODS: From January 2018 to December 2023, we assessed clinical outcomes and compared the experience levels of surgeons conducting tCVC insertions. Surgeons were categorized into three groups: junior residency (JR), senior residency (SR), and board-certified pediatric surgeons (BCPS). RESULTS: 177 tCVC insertions were done on 146 patients. Intraoperative complications included 6 cases of arterial puncture, 1 case of pneumothorax, 1 case of over insertion of catheter tip, and 1 case of suspected hemothorax. Distribution across groups was as follows: 28 cases (15.8%) in JR group, 92 (52.0%) in SR group, and 57 (32.2%) in BCPS group. Although the JR group exhibited longer operation times than the BCPS group, no significant differences in intraoperative complications were noted. CONCLUSION: Junior residents can safely perform UGSC for tCVC insertion. However, careful consideration of complications such as arterial or thoracic puncture is essential and case selection should be based on experience.

A case of late-presenting congenital diaphragmatic hernia diagnosed at 5 years with acute abdomen.

BACKGROUND: Some congenital diaphragmatic hernias are diagnosed beyond 1 month. A late-presenting congenital diaphragmatic hernia shows a variety of clinical manifestations, and the preoperative clinical course is variable. We herein report a pediatric case of late-presenting congenital diaphragmatic hernia diagnosed as acute abdomen. CASE PRESENTATION: A 5-year-old boy was brought to our hospital because of herniation of the intestine into the left thoracic cavity, which was observed on radiography performed for abdominal pain. Enhanced computed tomography showed herniation of the small intestine and colon into the left thoracic cavity. Emergency laparoscopic surgery was performed based on the diagnosis of left diaphragmatic hernia. The entire small intestine and part of the colon herniated from the posterolateral defect of the diaphragm. We were able to retract the herniated intestine back into the abdomen but confirmed that the diaphragmatic defect and closure of the defect seemed to be technically challenging via laparoscopy; therefore, we converted the procedure to open laparotomy. The diaphragmatic defect was directly closed with interrupted sutures, and the thoracic cavity was degassed. Postoperatively, the left lung was found to be poorly expanded, but pulmonary hypoplasia was not evident in this case. CONCLUSIONS: We herein report a pediatric case of late-presenting congenital diaphragmatic hernia diagnosed as abdominal pain. Late-presenting congenital diaphragmatic hernias present with a wide variety of symptoms; therefore, it is important to be reminded of these conditions and check chest radiographs in children presenting with acute or chronic respiratory or gastrointestinal symptoms of unknown etiology.

An unusual presentation of a rare formation of the common hepatic duct and right hepatic artery in a case of pediatric congenital biliary dilatation.

A 15-year-old girl with recurrent upper abdominal pain was diagnosed with congenital biliary dilatation. Abdominal enhanced computed tomography (CT) showed the anterior segmental branch of the right hepatic artery (RHA) running across the ventral aspect of the dilated common hepatic duct (CHD). Laparoscopic extrahepatic dilated biliary duct excision and Roux-en-Y hepaticojejunostomy were planned. Intraoperatively, the dilated CHD was observed to bifurcate into the ventral and dorsal ducts, between which the anterior segmental branch of the RHA crossed through the CHD. The CHD rejoined on the distal side as one duct. We transected the CHD just above the cystic duct. The patency of the ventral and dorsal sides of the bifurcated CHD was confirmed. Laparoscopic hepaticojejunostomy was performed at the distal side of the rejoined CHD, without sacrificing the anterior segmental branch of the RHA. There was no postoperative blood flow impairment in the right hepatic lobe or anastomotic stenosis.

Clinical outcome and neurological development of patients with biliary atresia associated with a bleeding tendency: a single institution experience.

PURPOSE: We compared the clinical features of patients with biliary atresia (BA) associated with a bleeding tendency (BT) at the time of the diagnosis with those of patients without a bleeding tendency (NBT). METHODS: The patients' background characteristics, age in days at the first visit, Kasai portoenterostomy (KPE), and postoperative course were retrospectively analyzed. RESULTS: Nine of the 93 BA patients (9.7%) showed a BT, including 7 with intracranial hemorrhaging (ICH), 1 with gastrointestinal bleeding, and 1 with a prothrombin time (PT) of 0%. The age at the first visit was 62 ± 12 days old for BT patients and 53 ± 27 days old for NBT patients (p = 0.4); the age at KPE was 77 ± 9 days old for BT patients and 65 ± 24 days old for NBT patients (p = 0.2); the time from the first visit to surgery was 13 ± 7 days for BT patients and 11 ± 10 days for NBT patients (p = 0.5); and the native liver survival rate was 56% for BT patients and 58% for NBT patients (p = 1), with no significant difference in any of the parameters. The neurological outcomes of survivors of ICH were favorable. CONCLUSIONS: Appropriate BT correction allowed early KPE even after ICH, resulting in native liver survival rates comparable to those of NBT patients without significant neurological complications.

Notable Clinical Differences Between Neonatal and Post-Neonatal Intestinal Malrotation: A Multicenter Review in Southern Japan.

BACKGROUND: Most cases of intestinal malrotation appear in neonates with bilious vomiting due to midgut volvulus, whereas in cases that develop beyond infancy, the initial symptoms vary. This study investigated the clinical features of these two populations and identified issues that should be considered in daily practice. METHODS: A retrospective chart review was conducted from January 1, 2010, to December 31, 2022. Data on patients with intestinal malrotation were collected in an anonymized fashion from five pediatric surgical hub facilities in the Southern Kyushu and Okinawa areas of Japan. RESULTS: Of the 80 subjects, 57 (71.3%) were neonates (Group N) and 23 (28.7%) were infants and schoolchildren (Group I). The frequencies of initial symptoms, such as abdominal distention (Group N: 19.3% vs. Group I: 13.0%), bilious vomiting (59.6% vs. 43.5%), and hematochezia (8.8% vs. 21.7%), were not skewed by the age of onset (p = 0.535, 0.087, and 0.141, respectively). Midgut volvulus was significantly more frequent in Group N (71.9% [41/57] vs. 34.8% [8/23]; p = 0.005), while the degree of torsion was greater in group I (median 360° [interquartile range: 180-360°] vs. 450° [360-540°]; p = 0.029). Although the bowel resection rate was equivalent (7.0% [4/57] vs. 4.3% [1/23]; p = 1.000), half of the patients in Group N presented with 180° torsion. The neonatal intestine has been highlighted as being more susceptible to ischemia than that in older children. CONCLUSIONS: The incidence of midgut volvulus is higher in neonates than in older children. Even relatively mild torsion can cause ischemic bowel changes during the neonatal period. LEVEL OF EVIDENCE: LEVEL III.

Proctoring System of Pediatric Laparoscopic Surgery for Choledochal Cyst.

Background: Endoscopic surgery also has been becoming widespread in the field of pediatric surgery. However, most disease treated by pediatric surgery in a single institution are small number of cases. Besides, the variety of operative procedures that need to be performed in this field is quite wide. For these reasons, pediatric surgeons have limited opportunities to perform endoscopic surgery. Therefore, it is difficult to introduce advanced endoscopic surgery at a single local hospital. To educate pediatric surgeons in local hospitals, for widespread advanced pediatric endoscopic surgery safely, and to eliminate the need for patient centralization, we have introduced a proctoring system. We compared the surgical results of our institution, a center hospital, with other local institutions, to investigate the feasibility of our proctoring system. Methods: The experienced pediatric surgeon of our institution visits local hospitals to provide onsite coaching and supervises pediatric surgeons on the learning curve. All patients who underwent laparoscopic cyst excision and hepaticojejunostomy for choledochal cysts, one of the advanced pediatric endoscopic surgeries was retrospectively reviewed. Results: Thirty-four cases were evaluated (14 cases in our institution, 20 cases in 9 other institutions). The procedures of all 34 cases were performed by surgeons with 0-2 cases of experience in the procedure. There were no open conversion cases. There was no significant difference in the operative date. There was 1 case (6.7%) of postoperative complications during hospitalization at our institution and 3 cases (14.3%) at other institutions (P = .47). Two cases of late complications (13.3%) occurred at our institution, whereas 6 cases (28.6%) occurred at other institutions (P = .28). Conclusion: With the proctoring system, the performance and completion of advanced pediatric endoscopic surgery at local institutions was feasible. This has important implications given the ever-growing demand for pediatric endoscopic surgery and the increasing need for competent pediatric endoscopic surgeons.

Feasibility of Laparoscopic Fundoplication Without Removing the Preceding Gastrostomy in Severely Neurologically Impaired Patients: A Multicenter Evaluation of the Traction Technique.

Purpose: Severely neurologically impaired patients sometimes require anti-reflux surgery with preceding gastrostomy. We apply a traction technique for laparoscopic fundoplication (LF) without gastrostomy takedown (GTD) in such cases. We conducted a multicenter review to assess the feasibility of our approach. Materials and Methods: In brief, the traction technique involves left-lateral-traction of the stomach body, right-lateral-traction of the round ligament of the liver, and elevation of the left liver lobe to create a sufficient field for manipulating the forceps. Patients who underwent LF with Nissen's procedures in 2010-2022 were retrospectively reviewed. Data were analyzed by a one-way analysis of variance. Results: The operative approaches included the traction technique (n = 16; Group 1), GTD and reconstruction (n = 5; Group 2), and LF followed by gastrostomy (n = 92; Group 3). In comparison with Group 1, significant differences were only found in pneumoperitoneum time (Group 1 versus Group 2 versus Group 3: 174.4 minutes versus 250.4 minutes versus 179.5 minutes; P = .0179). Operating time (222.7 minutes versus 303.0 minutes versus 239.7 minutes; P = .0743), duration to full-strength enteral nutrition (10.4 days versus 17.2 days versus 11.0 days; P = .0806), and length of hospital stay (17.2 days versus 31.0 days versus 18.5 days; P = .3247) were equivalent. No re-fundoplication was required in Group 1. Conclusion: The traction technique secures the operative quality and outcome of LF without GTD.

Association between gastrointestinal perforation and patent ductus arteriosus in extremely-low-birth-weight infants: a retrospective study of our decade-long experience.

PURPOSE: Management of persistently patent ductus arteriosus (PDA) in extremely low-birth-weight infants (ELBWIs) requires attention due to the risk of tissue hypoperfusion. We investigated the association between PDA and gastrointestinal perforation. METHODS: We performed a retrospective chart review from 2012 to 2021. Preterm (≤ 32 weeks) ELBWIs with PDA after birth who developed necrotizing enterocolitis (NEC), focal intestinal perforation (FIP), and idiopathic gastric perforation were included; ELBWIs with congenital heart disease were excluded. Data were analyzed using chi-squared tests with Yates; correction, and Student's t test. RESULTS: Five hundred thirty-five preterm ELBWIs were analyzed, including 20 with NEC, 22 with FIP, and 1 with gastric perforation. In NEC and FIP, the ductus arteriosus remained open in 40% (4/10) and 63.6% (14/22) of cases, respectively, and cyclo-oxygenase inhibitor treatment showed poor efficacy (p = 0.492 and 0.240). The incidence of perforation in NEC (4/9 vs. 6/11, p = 0.653), mortality in NEC (3/4 vs. 3/6, p = 0.895) and FIP (6/14 vs. 3/8, p = 0.838) did not differ according to whether the PDA persisted or resolved. CONCLUSION: The presentation of PDA did not affect the mortality or morbidity of ELBWIs. However, it is essential to consider the possibility of gastrointestinal perforation due to decreased organ blood flow caused by ductal steal.

Circulating maternal chimeric cells have an impact on the outcome of biliary atresia.

Introduction: We aimed to quantify the DNA of maternal chimeric (MC) cells in the peripheral blood of the BA patients and investigated the impact on the outcome. Methods: Patients with progressive jaundice because of no bile flow, which necessitated liver transplantation, or who showed inadequate bile flow with or without episodes of cholangitis and progressive hepatic fibrosis and portal hypertension were classified into the poor group. Those with adequate bile flow with completely normal liver function tests beyond 2 years were classified into the good group. The qPCR were separately carried out in buffy coat samples and plasma samples, targeting the non-inherited maternal HLA alleles in the DNA samples. Results: MC-DNA was present in the buffy coat (10-328 gEq per 106 host cells) in seven patients. There was no MC-DNA in the remaining five patients. MC-DNA (214-15,331 gEq per 106 host cells) was observed in the plasma of five patients. The quantity of MC-DNA in the buffy coat showed a significant difference between the two prognostic groups (p = 0.018), whereas there was no significant difference in the quantity of MC-DNA in plasma (p = 0.205). MC-DNA in the buffy coat was significantly associated with the outcome (p = 0.028), whereas MC-DNA in the plasma did not influence the outcome (p = 0.56). Conclusions: Poor outcomes in BA were correlated with circulating maternal chimeric lymphocytes.

Is anemia frequently recognized in gastroschisis compared to omphalocele? A multicenter retrospective study in southern Japan.

PURPOSE: We compared cases of anemia in gastroschisis versus omphalocele and investigated this clinical question. METHODS: A multicenter study of five pediatric surgery departments in southern Japan was planned. Sixty patients were collected between 2011 and 2020, with 33 (gastroschisis: n = 19, omphalocele: n = 14) who met the selection criteria ultimately being enrolled. Anemia was evaluated before discharge and at the first outpatient visit. RESULTS: Despite gastroschisis cases showed more frequent iron administration during hospitalization than omphalocele (p = 0.015), gastroschisis cases tended to show lower hemoglobin values at the first outpatient visit than omphalocele cases (gastroschisis: 9.9 g/dL, omphalocele: 11.2 g/dL). Gastroschisis and the gestational age at birth were significant independent predictors of anemia at the first outpatient visit, (gastroschisis: adjusted odds ratio [OR] 19.00, p = 0.036; gestational age at birth: adjusted OR 0.341, p = 0.028). A subgroup analysis for gastroschisis showed that the ratio of anemia in the 35-36 weeks group (8/10, 80.0%) and the > 37 weeks group (6/6, 100%) was more than in the < 34 weeks group (0/3, 0.0%). CONCLUSIONS: Gastroschisis may carry an increased risk of developing anemia compared with omphalocele due to the difference of direct intestinal exposure of amnion fluid in utero.

Using indocyanine green fluorescence in laparoscopic surgery to identify and preserve rare branching of the right hepatic artery in pediatric congenital biliary dilatation.

We describe a laparoscopic surgical technique using indocyanine green (ICG) fluorescence to identify and preserve rare arterial branching associated with pediatric congenital biliary dilatation. Congenital biliary dilatation with pancreaticobiliary maljunction was diagnosed in a 9-year-old girl, who presented with upper abdominal pain. Abdominal enhanced computed tomography (CT) showed that the accessory right hepatic artery (aRHA) branched from the posterior superior pancreaticoduodenal artery (PSPDA) and flowed through the right aspect of the dilated common bile duct (CBD) directly into the right lobe of the liver. We performed laparoscopic dilated biliary duct resection and hepaticojejunostomy, administering ICG intravenously, at a dose of 0.6 mg/kg. The ICG fluorescence overlay mode showed an aRHA running along the right side of the dilated CBD. The aRHA was dissected from the CBD without injury. After finishing the anastomosis, the beating of the aRHA was preserved, confirming that blood flow had been maintained.

Impact of the Number of Board-Certified Pediatric Surgeons per Pediatric Population on the Outcomes of Laparoscopic Fundoplication for Neurologically Impaired Patients.

Background and Aim: The distribution of board-certified pediatric surgeons (BCPSs) in Japan is highly biased. While Prefecture M has one of the smallest numbers of BCPSs per pediatric population, neighboring Prefecture K has one of the largest numbers of BCPSs per pediatric population. We examined the effect of BCPSs population on laparoscopic surgery and postoperative management and outcomes. Materials and Methods: We compared postoperative duration to full-dose enteral nutrition, postoperative hospital stay, and complications of neurologically impaired patients who underwent laparoscopic fundoplication in two prefectures from 2006 to 2019. Results: Laparoscopic fundoplication was performed in 17 patients in Prefecture M and 63 in K. The mean operative time was 248.8 ± 79.9 minutes in Prefecture M and 260.8 ± 94.8 in K (P = .64). The median number of days to full-dose enteral nutrition was 11.5 in Prefecture M and 10 in K (P = .29). The median postoperative hospital stay was 14 days in Prefecture M and 15 days in K (P = .38). Postoperative complications occurred in 7 cases in Prefecture M and in 10 in K. The incidence was significantly higher in Prefecture M than in K (P = .041). Conclusion: Areas with insufficient numbers of BCPSs have a higher risk of complications in laparoscopic surgery than areas with sufficient numbers.

Laparoscopic dome resection for pediatric nonparasitic huge splenic cyst safely performed using indocyanine green fluorescence and percutaneous needle grasper.

INTRODUCTION: In recent years, dome resection, which preserves the splenic immunological function, has been the primary technique used to treat splenic cysts. We herein report a surgical technique using a needle grasper and indocyanine green (ICG) fluorescence to perform dome resection of a huge nonparasitic splenic cyst in a pediatric patient. PATIENT AND SURGICAL TECHNIQUE: A 13-year-old girl was incidentally diagnosed with a splenic cyst during follow-up for scoliosis. Abdominal enhanced computed tomography (CT) showed a 17 × 14 × 14 cm unifocal cyst. Laparoscopic dome resection was planned. The intraoperative findings showed that the spleen was distended, but there was no apparent prominence of the thin cyst wall on the surface of the spleen. An ICG fluorescence camera overlay revealed poor coloration in the thinning area. We punctured the area and aspirated the cyst contents. We grasped the cyst wall with a percutaneous needle grasper and dissected the cyst wall with a vessel sealing system. We placed anti-adhesion agent at the dissection line to prevent recurrence. DISCUSSION: ICG fluorescence was useful for identifying the thinning area of a splenic cyst. The use of a percutaneous needle grasper facilitated the performance of dome resection of a huge splenic cyst in a pediatric patient with minimal invasiveness and an improved cosmetic outcome.

Biliary atresia: graft-versus-host disease with maternal microchimerism as an etiopathogenesis.

Biliary atresia (BA) is an inflammatory disease of the biliary system in newborns and infants. The etiology is largely unknown. Approximately half of BA patients require liver transplantation by 20 years of age, even after surgical correction due to progressive fibrosis of the liver. Regarding the disease mechanism, there is circumstantial evidence to support the hypothesis of graft-versus-host disease because of the existence of maternal cells in the liver (maternal microchimerism, MMC), histopathological similarity of the liver and an intense maternal response to the BA patient with mixed lymphocyte culture. Immune dysregulation with decreased Treg and increased Th1 and Th17 cells are the pathogenic features of BA, which are homologous to the pathogenic features of GvHD. Further elucidation of the etiopathogenetic mechanism of BA is warranted for development of new therapeutic strategies for native liver survival.

Optimal timing of definitive surgery for Hirschsprung's disease to achieve better long-term bowel function.

PURPOSE: Few studies have focused on the operative age for Hirschsprung's disease (HD). We evaluated the optimal timing of surgery in HD patients based on their long-term bowel function. METHODS: HD was diagnosed in 65 pediatric patients in our institute between 1992 and 2018. Twenty-five patients underwent the Soave-Denda procedure (SD) and 40 underwent transanal endorectal pull-through (TA). We divided these patients into two groups: those who underwent surgery at < 6 months of age (younger group) and those who underwent surgery at 6-12 months of age (older group). We assessed bowel function at 5, 7, and 9 years of age. RESULTS: The bowel function of the patients who underwent the SD did not differ significantly between the groups. Similarly, the total bowel-function scores of the patients who underwent TA did not differ between the groups at any age. However, the soiling score at 7 years of age in the older group of patients who underwent TA was significantly lower than that in the younger group (p = 0.02). CONCLUSIONS: Our data suggest that to achieve optimal bowel function, TA should be performed at < 6 months of age.

A retrospective analysis of the real-time ultrasound-guided supraclavicular approach for the insertion of a tunneled central venous catheter in pediatric patients.

PURPOSE: Tunneled central venous catheter (tCVC) placement plays an important role in the management of pediatric patients. We adopted a real-time ultrasound (US)-guided supraclavicular approach to brachiocephalic vein cannulation. We evaluated the outcomes of tCVC placement via a US-guided supraclavicular approach. METHODS: A retrospective study was performed for patients who underwent US-guided central venous catheterization of the internal jugular vein (IJV group) and brachiocephalic vein (BCV group) in our institution. The background information and outcomes were reviewed using medical records. RESULTS: We evaluated 85 tCVC placements (IJV group: n = 59, BCV group: n = 26). Postoperative complications were recognized in 19 patients in the IJV group (catheter-related bloodstream infection (CRBSI), n = 14 (1.53 per 1000 catheter days); occlusion, n = 1 (1.7%, 1.09 per 1000 catheter days); accidental removal, n = 3 (5.2%, 0.33 per 1000 catheter days); and other, n = 1 (1.7%, 1.09 per 1000 catheter days)) and five patients in the BCV group (CRBSI, n = 2 (0.33 per 1000 catheter days); catheter damage, n = 1 (3.8%, 1.67 per 1000 catheter days); and accidental removal, n = 2 (7.7%, 0.33 per 1000 catheter days)). In the BCV group, despite that, the incidence of postoperative complications was lower (p = 0.205) and the period of placement was significantly longer in comparison to the IJV group (p = 0.024). CONCLUSION: US-guided placement of tunneled CVC though the BCV results in a low rate of postoperative complications despite longer CVC indwelling times compared to IJV insertion. Our results suggest that BCV insertion of tunneled CVC in children may offer advantages in terms of device performance and patient safety.

A Metastatic Neuroblastic Tumor in a 28-Month-old Boy: Unusual Spontaneous Regression From Neuroblastoma to Ganglioneuroma?

Neuroblastoma with bone metastasis is well known to have an extremely poor prognosis. We experienced the case of a patient with adrenal ganglioneuroblastoma (GNB) with metastases of subcutaneous nodules, a lymph node, and multiple bones. A pathologic examination of tumors from different sites revealed both GNB and ganglioneuroma. A genetic comparison between these tumors identified the same molecular signatures, suggesting the possibility of spontaneous differentiation in the remaining GNB. The patient has been healthy without aggressive chemotherapy, and the patient's pathologic urinary catecholamines normalized. Even if unusual, we have to recognize probable spontaneous differentiation from neuroblastoma to GNB and then to ganglioneuroma, even in sites of bone metastasis.

Retroperitoneal teratomas in children: a single institution experience.

PURPOSE: Retroperitoneal teratomas (RPTs) are rare in infants. We report our experience of treating pediatric patients with RPTs over many years at a single institution, with the aim of developing a safe and secure operative strategy for RPTs in infants. METHODS: We reviewed the medical records of patients who underwent treatment for RPTs in our institution between April, 1984 and December, 2017, to analyze their background and clinical data. The diagnosis of RPT was confirmed histologically in all patients. RESULTS: The subjects of this retrospective analysis were 14 pediatric patients (female, n = 11; male, n = 4), ranging in age from 6 days to 12 years, 11 (73.3%) of whom were under 1 year of age. Complete surgical resection was performed in all patients. The tumor ruptured during surgery in four (26.7%) patients and perioperative vessel injuries occurred in six (40.0%) patients, resulting in nephrectomy in one (6.7%). Three (20.0%) patients suffered unilateral renal dysfunction as a surgical complication. Only one patient received postoperative chemotherapy. All patients were free of disease at the time of writing. CONCLUSION: Perioperative complications are not uncommon during surgery for RPTs, despite their benign nature. Preoperative imaging evaluation is important and operative management may be challenging. Because of the favorable prognosis and the frequency of adverse events in surgery, partial resection or split excision is sometimes unavoidable. Meticulous follow-up for recurrence is required for such patients.

Malignant perivascular epithelioid cell neoplasm in the liver: report of a pediatric case.

BACKGROUND: Perivascular epithelioid cell neoplasm (PEComa) in a child is very rare. We herein report the first malignant case of PEComa developing in the liver of a pediatric patient. CASE PRESENTATION: A 10-year-old boy visited a private clinic with prolonged fever of unknown etiology. Abdominal ultrasonography was performed to evaluate the fever's origin, revealing a large tumor in the liver. He was thus referred to a nearby hospital to investigate the tumor further. Enhanced computed tomography (CT) showed a 6.8 × 5.9 × 10.5-cm solid lesion on S4 and S5. On magnetic resonance imaging (MRI), the tumor had a low signal intensity on T1 imaging and high signal intensity on T2 imaging, with partial diffusion restriction. 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) showed a marked uptake in the mass lesion with no evidence of metastasis. The patient was negative for all tumor markers, including AFP, CEA and PIVKA-II. The results of a needle biopsy suggested hepatocellular carcinoma. The tumor's rapid growth suggested malignancy. Hepatic segmentectomy (S4 + S5 + S8) was performed. The tumor was resected en bloc with a margin. Microscopically, the tumor showed atypical spindle, polygonal or oval-shaped cells with a high nuclear grade, and vascular invasion. Immunohistochemistry was positive for alpha-smooth muscle antigen (α-SMA), human melanin black-45 (HMB-45) and melan A. The pathological diagnosis was malignant PEComa. In the 6 months after surgery, the patient complained of shoulder pain. MRI showed a dumbbell-shaped tumor at the 2nd thoracic vertebrae, which was confirmed to be bone metastasis of PEComa. After chemotherapy, including ifosfamide and doxorubicin, vertebrectomy was performed. Two years later, thoracoabdominal CT showed a 10-cm solid mass occupying the pelvis and a 15-mm nodule in the middle lobe of the right lung. Under a diagnosis of peritoneal and lung metastases, they were surgically removed and metastasis of PEComa was pathologically confirmed. Four months after the 2nd relapse, pelvic metastasis appeared again and mTOR (mammalian target of rapamycin) inhibitor was initiated. To our knowledge, this is the first report of malignant hepatic PEComa in a pediatric patient. CONCLUSION: Although extremely rare, malignant hepatic PEComa can develop in a child.