[Endolymphatic sac tumor with von Hippel-Lindau disease: report of two cases with testing of von Hippel-Lindau gene].

Objective: Endolymphatic sac tumors (ELSTs) are rare in the general population with much higher prevalence in von Hippel-Lindau(VHL) disease. The purpose of this study is to present two cases of endolymphatic sac tumor with VHL disease with analysis of VHL gene and to explore their association with VHL disease using molecular analysis.

Methods: Clinical data of these two patients from different VHL families were studied. DNAs extracted from peripheral bloods were amplified by the polymerase chain reaction using oligonucleotide primers corresponding to the VHL gene, then compared the mutations with the Human Gene Mutation Database.

Results: In case 1, 6 family members were enrolled in the study. Among them, three had been identified to have a germline missense point mutation at codon 194 of the VHL gene exon 1 (p.S65W). The little sister of the patient (case 1) underwent vitrectomy for retinal hemangioblastoma 5 years ago in another hospital. The mother of the patient (case 1) was further diagnosed to have a cerebellar hemangioblastoma and renal carcinoma in the following physical examination. Case 2 with her parents were also tested. Codon 499 of the VHL gene exon 3 (p.R167W) were detected in case 2 and her mother, but the mother refused further examination.

Conclusions: The genetic diagnosis plays an important role in early detection of symptomatic patients and suspected patients. Clinical screening for members of the VHL families, and close follow-up of carriers allow an early detection of tumors and the metastasis, which is the most common cause of death of these patients.