A novel fluorescence in situ hybridization assay for synovial sarcoma.

Synovial sarcoma, which is difficult to diagnose precisely, is one of the most common childhood nonrhabdomyosarcoma soft-tissue sarcomas. The purpose of this study is to develop new molecular cytogenetic assay. We used two sets of two-color break-apart FISH probes, flanking either the SSX1/SSX4 or SSX2 locus. Each set of probes is composed of differentially labeled DNA fragments complementary to sequences proximal or distal to the break point within the SSX1/SSX4 or SSX2 locus, which are applied separately to histopathological sections. Interphase nuclei containing a translocation that disrupts either SSX1, SSX2, or SSX4 locus will display two single-color signals that have "broken apart" from each other. We applied it to two synovial sarcoma cell lines and clinical samples. This assay can detect translocation at either SSX1/SSX4, or SSX2 locus on interphase spread prepared from synovial sarcoma cell line and histopathological sections, which is sufficient to diagnose as synovial sarcoma. Our new FISH assay has several advantages, including its applicability to paraffin-embedded samples, discrimination of the SS18-SSX1 and SS18-SSX2 translocations particularly in cases with aneuploidy, and potentially detecting translocations in all cases of synovial sarcoma, even with variant translocations. Our strategy will improve the accuracy of diagnoses, thereby facilitating appropriate treatment planning.

Pericardial hemangioma presenting fetal cardiac tamponade and postnatal bronchostenosis.

A case of pericardial hemangioma is described which was resected in the neonatal period due to its effect on the cardiopulmonary system. Preoperative differential diagnosis of a teratoma was difficult. Surgical extirpation resulted in massive bleeding and postoperative bronchomalacia. These complications suggest that we should choose a conservative therapy as often as possible.

Evaluation of the PELD risk score as a severity index of biliary atresia.

PURPOSE: The authors evaluated the validity of the Pediatric End-Stage Liver Disease (PELD) Risk Scoring System as a severity index for patients with biliary atresia. METHODS: Individual hospital records of 104 patients with biliary atresia were reviewed at our institution and divided into 3 groups: nontransplant survivors (n = 61), nontransplant deaths (n = 17), and transplant patients (n = 26). PELD risk scores were calculated according to Wiesner et al, multiplied by 10, and rounded to the nearest integer, as is done in determining model of end-stage liver disease (MELD) scores. RESULTS: The PELD scores showed a significant difference between nontransplant survivors (range, -21 to 15) and dying nontransplant patients during their last few months of life (range, 2 to 40). No survivors except those below the age of one year recorded scores above 10. Transplant patients had higher scores (range, -5 to 37) before transplantation than nontransplant survivors. However, the scores were not elevated in elderly patients with intractable cholangitis, fulminant variceal rupture, and hepatopulmonary syndrome. CONCLUSIONS: PELD profiling is a useful scoring system for selecting patients with the most severe liver dysfunction caused by biliary atresia. However, we advise caution in using this system for patients under the age of 1 year and for older patients with long-term complications.

Increased Ras expression and caspase-independent neuroblastoma cell death: possible mechanism of spontaneous neuroblastoma regression.

BACKGROUND: Neuroblastoma undergoes spontaneous regression frequently during its natural course. Although programmed cell death (PCD) has been implicated in this process, accumulating evidence suggests that apoptosis, a form of PCD that is regulated by caspases, may not play a major role. We examined the mechanism(s) of spontaneous regression of neuroblastoma, focusing on the role of Ras, a favorable prognostic marker of neuroblastoma. METHODS: Tumor tissues were analyzed by light microscopy, electron microscopy, and immunohistochemistry to examine cell degeneration and expression of Ras and several indicators of PCD. Cell degeneration was also studied in vitro in neuroblastoma cells transfected with the H-ras gene. All statistical tests were two-sided. RESULTS: Immunohistochemical analyses revealed that Ras expression was increased in areas of cellular degeneration lacking apoptotic characteristics. The degenerating cells were fragmented without nuclear condensation and, essentially, lacked caspase-3 activation and apoptotic DNA fragmentation. These cells had ultrastructural features of autophagic degeneration, another form of PCD that is distinct from apoptosis. Focal areas of degeneration associated with Ras expression were seen more frequently in tumors from patients detected in a mass-screening program (53 [60.9%] of 87) than in tumors from clinically detected, advanced-stage patients over 1 year of age (7 [29.2%] of 24) (P =.006; chi-square test), suggesting a positive relationship between Ras-associated degeneration and probability of spontaneous regression/favorable prognosis. The characteristic features of Ras-associated nonapoptotic degeneration observed in tumor samples were recapitulated in vitro by transfection-mediated Ras expression, and Ras-mediated degeneration was augmented by TrkA, another favorable prognostic marker. CONCLUSIONS: High-level expression of H-Ras in neuroblastoma cells is associated with caspase cascade-independent, nonapoptotic PCD. This Ras-mediated nonapoptotic tumor cell death may play a key role in spontaneous regression of neuroblastoma.