Clear cell sarcomas of the kidney are characterised by BCOR gene abnormalities, including exon 15 internal tandem duplications and BCOR-CCNB3 gene fusion.

AIMS: Clear cell sarcoma of the kidney (CCSK) is a rare paediatric renal malignant tumour. The majority of CCSKs have internal tandem duplications (ITDs) of the BCOR gene, whereas a minority have the YWHAE-NUTM2 gene fusion. A third 'double-negative' (DN) category comprises CCSKs with neither BCOR ITDs nor YWHAE-NUTM2 fusion. The aim of this study was to characterise 11 histologically diagnosed CCSKs immunohistochemically (with CCND1, BCOR and CCNB3 stains) and genetically. METHODS AND RESULTS: By next-generation sequencing, 10 cases (90.9%) had BCOR exon 15 ITDs, with positive BCOR immunoreactivity being found in four (36%) or eight (72%) cases, depending on the antibody clone. By reverse transcription polymerase chain reaction, none had the YWHAE-NUTM2 fusion. The DN case had a BCOR-CCNB3 fusion and strong nuclear CCNB3 and BCOR immunoreactivity. Quantitative polymerase chain reaction showed markedly elevated BCOR expression in this case, whereas BCOR ITD cases had lower levels of elevated BCOR expression. CONCLUSIONS: The majority of the CCSKs in our cohort had BCOR ITDs, and none had the YWHAE-NUTM2 fusion. We verified the strong, diffuse cyclin D1 (CCND1) immunoreactivity in CCSKs described in recent reports. BCOR immunoreactivity was not consistently positive in all CCSKs with BCOR ITDs, and therefore cannot be used as a diagnostic immunohistochemical stain to identify BCOR ITD cases. The DN case was a BCOR-CCNB3 fusion sarcoma. BCOR-CCNB3 sarcoma is typically a primary bone sarcoma affecting male adolescents, and this is the first report of it presenting in a kidney of a young child as a CCSK. The full spectrum of DN CCSKs awaits more comprehensive characterisation.

Hypoalbuminemia and early mortality after lung transplantation: a cohort study.

Hypoalbuminemia predicts disability and mortality in patients with various illnesses and in the elderly. The association between serum albumin concentration at the time of listing for lung transplantation and the rate of death after lung transplantation is unknown. We examined 6808 adults who underwent lung transplantation in the United States between 2000 and 2008. We used Cox proportional hazard models and generalized additive models to examine multivariable-adjusted associations between serum albumin and the rate of death after transplantation. The median follow-up time was 2.7 years. Those with severe (0.5-2.9 g/dL) and mild hypoalbuminemia (3.0-3.6 g/dL) had posttransplant adjusted mortality rate ratios of 1.35 (95% CI: 1.12-1.62) and 1.15 (95% CI: 1.04-1.27), respectively. For each 0.5 g/dL decrease in serum albumin concentration the 1-year and overall mortality rate ratios were 1.48 (95% CI: 1.21-1.81) and 1.26 (95% CI: 1.11-1.43), respectively. The association between hypoalbuminemia and posttransplant mortality was strongest in recipients with cystic fibrosis and interstitial lung disease. Hypoalbuminemia is an independent risk factor for death after lung transplantation.