Child ; Cytogenetic Analysis ; Forecasting ; Humans ; Immunohistochemistry ; Pathology, Clinical ; methods ; trends ; Pediatrics ; methods ; trends

Adolescent ; Child ; Female ; Humans ; In Situ Hybridization, Fluorescence ; methods ; Leg ; Male ; Paraffin Embedding ; Sarcoma, Synovial ; diagnosis ; genetics ; pathology ; Soft Tissue Neoplasms ; diagnosis ; genetics ; pathology ; Translocation, Genetic

Cardiomyopathies ; pathology ; Cardiomyopathy, Dilated ; pathology ; Child ; Child, Preschool ; Humans

OBJECTIVETo study the clinicopathologic features of metanephric stromal tumor (MST), with emphasis on diagnostic criteria.

METHODSThe clinicopathologic findings in 2 cases of MST were analyzed and the literature of this entity was reviewed.

RESULTSCases of MST were unilateral and mostly centered in renal medulla. The tumor was separated from adjacent renal tissue by sharp and scalloped borders. Entrapped tubules and glomeruli were commonly seen within the lesion. The tumor cells were spindle to stellate in shape and arranged in a nodular pattern. On low power examination, alternating areas of high and low tumor cellularity were noted. Characteristically, there were onion skin-like concentric cuffs of tumor cells around entrapped tubules. The small intratumoral vasculatures showed irregular thickening ("angiodysplasia"). Immunohistochemical study demonstrated that the tumor cells diffusely expressed CD34.

CONCLUSIONSWhich the tumor cells around the entrapped renal tubules and blood vessels imparts a nodular appearance, as well as the tumor cells labbed for CD34 are the highly characteristic pathologic findings of MST.

Antigens, CD34 ; metabolism ; Diagnosis, Differential ; Female ; Follow-Up Studies ; Humans ; Infant, Newborn ; Kidney ; pathology ; Kidney Neoplasms ; immunology ; pathology ; surgery ; Male ; Nephrectomy ; Stromal Cells ; pathology

BACKGROUNDVon Hippel-Lindau (VHL) syndrome is an autosomal dominant familial cancer syndrome predisposing the affected individuals to multiple tumours in various organs. The genetic basis of VHL in Southern Chinese is largely unknown. In this study, we characterized the mutation spectrum of VHL in nine unrelated Southern Chinese families.

METHODSNine probands with clinical features of VHL, two symptomatic and eight asymptomatic family members were included in this study. Prenatal diagnosis was performed twice for one proband. Two probands had only isolated bilateral phaeochromocytoma. The VHL gene was screened for mutations by polymerase chain reaction, direct sequencing and multiplex ligation-dependent probe amplification (MLPA).

RESULTSThe nine probands and the two symptomatic family members carried heterozygous germline mutations. Eight different VHL mutations were identified in the nine probands. One splicing mutation, NM_000551.2: c.463+1G > T, was novel. The other seven VHL mutations, c.233A > G [p.Asn78Ser], c.239G > T [p.Ser80Ile], c.319C > G [p.Arg107Gly], c.481C > T [p.Arg161X], c.482G > A [p.Arg161Gln], c.499C > T [p.Arg167Trp] and an exon 2 deletion, had been previously reported. Three asymptomatic family members were positive for the mutation and the other five tested negative. In prenatal diagnosis, the fetuses were positive for the mutation.

CONCLUSIONSGenetic analysis could accurately confirm VHL syndrome in patients with isolated tumours such as sporadic phaeochromocytoma or epididymal papillary cystadenoma. Mutation detection in asymptomatic family members allows regular tumour surveillance and early intervention to improve their prognosis. DNA-based diagnosis can have an important impact on clinical management for VHL families.

Asian Continental Ancestry Group ; DNA Mutational Analysis ; Humans ; Polymerase Chain Reaction ; Sequence Analysis, DNA ; Von Hippel-Lindau Tumor Suppressor Protein ; genetics ; von Hippel-Lindau Disease ; genetics