Suk Koo Lee

Withdrawal of Immunosuppression in Pediatric Liver Transplant Recipients in Korea

Purpose We identified pediatric liver transplant recipients with successful withdrawal of immunosuppression who developed tolerance in Korea. Materials and Methods Among 105 pediatric patients who received liver transplantation and were treated with tacrolimus-based immunosuppressive regimens, we selected five (4.8%) patients who had very low tacrolimus trough levels. Four of them were noncompliant with their medication and one was weaned off of immunosuppression due to life threatening posttransplant lymphoproliferative disorder. We reviewed the medical records with regard to the relationship of the donor-recipients, patient characteristics and prognosis, including liver histology, and compared our data with previous reports. Results Four patients received the liver transplantation from a parent donor and one patient from a cadaver donor. A trial of withdrawal of the immunosuppressant was started a median of 45 months after transplantation (range, 14 months to 60 months), and the period of follow up after weaning from the immunosuppressant was a median of 32 months (range, 14 months to 82 months). None of the five patients had rejection episodes after withdrawal of the immunosuppression; they maintained normal graft function for longer than 3 years (median, 38 months; range, 4 to 53 months). The histological findings of two grafts 64 and 32 months after weaning-off of the medication showed no evidence of chronic rejection. Conclusion The favorable markers for successful withdrawal of immunosuppression were 1) long-term (> 3 years) stable graft function, 2) no rejection for longer than 1 year after withdrawal of immunosuppression, 3) non-immune mediated liver diseases, and 4) pediatric patients.

Long-term follow-up of de novo allergy in pediatric liver transplantation – 10 yr experience of a single center

We conducted a study to clarify the incidence, clinical course, and risk factors of de novo allergies after liver transplantation. Ninety‐three patients who had been followed longer than one yr and who had no previous allergy history were included. Forty‐two patients (45.2%) developed de novo allergy. Of them, food allergy developed in 35 (37.6%). Respiratory allergy was observed in three (3.2%), and a patient (1.1%) had drug allergy. Fifty‐two (55.9%) of the 93 patients developed eosinophilia. The median age of patients with de novo allergy was 15 months (IR 11.3–20 months). De novo allergy developed five months after liver transplantation (IR 2.3–9.5 months) and lasted for 16 months (IR 8–34.5 months). Younger age at liver transplantation displayed statistically significant differences in development of allergy between allergy and non‐allergy groups. Twenty‐nine (69.0%) patients improved from allergy during the follow‐up period. No patient with de novo gastrointestinal allergy progressed to any respiratory allergy such as asthma. Older age at transplantation, EBV non‐risk, and CMV non‐risk had statistical significance in allergy improvement. Younger age at transplant predisposes to the development of allergy, while improvement of allergy is achieved more in older age.

Neuroblastoma Originating from Extra-abdominal Sites: Association with Favorable Clinical and Biological Features

Neuroblastomas originating from different sites might have different clinical and biological characteristics. In the present study, the clinical (age, sex and stage) and biological (N-myc amplification, Shimada pathology and levels of lactate dehydrogenase, ferritin and neuron-specific enolase) characteristics of patients with newly diagnosed neuroblastoma were compared according to the site of tumor origin (extra-abdominal versus abdominal). The event-free survival rate (EFS) was also compared between the two groups. Among 143 neuroblastomas, 115 tumors originated from the abdomen, 26 from extra-abdominal sites and 2 from unknown primary sites. Frequencies of stage 4 tumor and N-myc amplified tumor were lower in the extra-abdominal group than in the abdominal group (34.6% vs. 60.0%, P=0.019 and 4.2% vs. 45.0%, P<0.001, respectively). Levels of lactate dehydrogenase, ferritin and neuron-specific enolase were significantly lower in the extra-abdominal group than in the abdominal group. The probability of 5-yr EFS (±95% confidence interval) was higher in the extra-abdominal group than in the abdominal group (94.4±10.6% vs. 69.4±9.4%, P=0.026). Taken together, neuroblastomas originating from extra-abdominal sites might be associated with more favorable clinical and biological characteristics and a better outcome than neuroblastomas originating from abdomen.

Fibrous hamartoma of infancy: an experience of a single institute

Purpose Fibrous hamartoma (FH) of infancy is a distinctive fibrous growth that most frequently occurs at birth and during the postnatal period. It is important for clinicians and pathologists to recognize this entity to avoid an aggressive approach. Methods We herein describe the clinicopathologic features of 9 FHs diagnosed at a single institution between 1997 and 2010. Results There were 7 boys and 2 girls, and the mean age of presentation was 14.7 months. The common locations were the lower back and gluteal region (n = 3) and scrotum (n = 2). They were solitary lesions, and measured 1.0 to 7.0 cm in maximum diameter (mean, 4.9 cm). The excised masses tended to be poorly circumscribed, and consisted of an intimate mixture of firm, gray-white tissue with fat. Histologically, these lesions were composed of 3 components forming a vague, irregular, organoid pattern: well-defined intersecting trabeculae of fibrocollagenous tissue; loosely textured areas of small, rounded, primitive mesenchymal cells; and mature fat. Over a median follow-up of 72 months, no patient showed recurrence. Conclusion FH should be distinguished from other forms of fibromatosis and malignant tumors because it is benign and usually cured by local excision.

Older donor allografts are associated with poor patient survival after living donor liver transplantation for hepatitis B virus-related liver diseases

Background and Aims: The significance of donor age in living donor liver transplantation (LDLT) for hepatitis B virus (HBV) infection has not been fully evaluated.

A Single Center Experience of Self-Bougienage on Stricture Recurrence after Surgery for Corrosive Esophageal Strictures in Children

Purpose This study was undertaken to evaluate the long-term treatment of esophageal strictures in children with corrosive esophagitis and to determine the effect of self-bougienage on recurrent strictures. Materials and Methods We reviewed the medical records of nine children that were treated for corrosive esophageal strictures from May 2000 to May 2008. Six males and three females were included and their average age was 30 months. Six patients had ingested acids, two patents had ingested alkali, and one ingested an unknown agent. Results The interval between caustic ingestion and esophageal stricture ranged from one to eight weeks. The average length of the esophageal strictures was 3.8 cm (range, 1 to 9.2 cm). Four patients had a long segment stricture (longer than 5 cm) and one patient had multiple strictures. The most common site of involvement was the upper third followed by the mid third of the esophagus. Eight patients received repeated dilatation using a balloon catheter or bougie dilator. Among the eight patients, two patients had complete resolution of symptoms and six patients required surgery. Among five patients that developed restenosis of the esophageal anastomosis site, three patients had improved symptoms after self-bougienage and two patients had improved symptoms with repeated balloon dilatation or endoscopic bougienage. There were no complications in these patients. Conclusion Although a small number of patients were studied, self-bougienage was safe, less invasive, and effective for the management of esophageal restenosis in patients who required frequent dilation after surgery.

High-dose Chemotherapy and Autologous Stem Cell Rescue in Patients with High-risk Stage 3 Neuroblastoma: 10-Year Experience at a Single Center

High-dose chemotherapy and autologous stem cell rescue (HDCT/ASCR) was applied to improve the prognosis of patients with high-risk stage 3 neuroblastoma. From January 1997 to December 2006, 28 patients were newly diagnosed as stage 3 neuroblastoma. Nine of 11 patients with N-myc amplification and 5 of 17 patients without N-myc amplification (poor response in 2 patients, persistent residual tumor in 2 and relapse in 1) underwent single or tandem HDCT/ASCR. Patients without high-risk features received conventional treatment modalities only. While 8 of 9 patients underwent single HDCT/ASCR and the remaining one patient underwent tandem HDCT/ASCR during the early study period, all 5 patients underwent tandem HDCT/ASCR during the late period. Toxicities associated with HDCT/ASCR were tolerable and there was no treatment-related mortality. While the tumor relapsed in two of eight patients in single HDCT/ASCR group, all six patients in tandem HDCT/ASCR group remained relapse free. The 5-yr event-free survival (EFS) from diagnosis, in patients with N-myc amplification, was 71.6±14.0%. In addition, 12 of 14 patients who underwent HDCT/ASCR remained event free resulting in an 85.1±9.7% 5-yr EFS after the first HDCT/ASCR. The present study demonstrates that HDCT/ASCR may improve the survival of patients with high-risk stage 3 neuroblastoma.

Prognostic factors in children with extracranial germ cell tumors treated with cisplatin-based chemotherapy.

Purpose To evaluate the outcomes and prognostic factors in children with extracranial germ cell tumors (GCTs) treated at a single institution. Methods Sixty-six children diagnosed with extracranial GCTs between 1996 and 2012 were included in the study. Primary treatment was surgical excision, followed by six cycles of cisplatin-based chemotherapy. The survival rates were compared according to the International Germ Cell Cancer Cooperative Group classification used for GCTs in adults to validate the classification guidelines for GCTs in children. Results The median patient age was 4.4 years. In 34 patients (51.5%), the primary tumor site was the gonad. Extragonadal GCTs were detected in 32 patients. The 5-year overall survival and event-free survival (EFS) were 92.0%±3.5% and 90.4%±3.7%, respectively. In univariate analysis, tumor histology, metastasis, and elevated alpha-fetoprotein were not prognostic factors in children with extracranial GCTs. However, EFS was poorer in patients with mediastinal disease (n=12, 66.7%±13.6 %) than in those with nonmediastinal disease (n=54, 96.0%±2.8%) (P=0.001). The 5-year EFS was lower in patients older than 10 years, (n=21, 80.0%±8.9%) compared with those younger than 10 years (n=45, 95.2%±3.3%) (P=0.04). Multivariate analysis identified the mediastinal tumor site as the only independent prognostic factor. Conclusion The prognosis of children with extracranial GCTs was favorable. However, nongerminomatous mediastinal tumors were associated with poor survival in children. Further research is needed to improve the prognosis of children with malignant mediastinal GCTs.