Akademik Veri Yönetim Sistemi
International Hereditary Cancers Congress, Antalya, Türkiye, 6 - 09 Şubat 2025, ss.172, (Özet Bildiri)
Hilal Gölcür, Elif Saraç, Sinem Kocagil
Objective: This study presents a 4-year-old male patient diagnosed with bilateral cystic nephroma, in whom a pathogenic germline DICER1 variant was identified.
Case: The patient was referred to our clinic after the parents noticed an abdominal mass when the child was 1 year old. An abdominal ultrasound revealed a multilocular cystic structure in the left kidney, prompting further evaluation with a differential diagnosis of nephroblastoma and nephroma. After performing a left radical nephrectomy, the pathology result confirmed cystic nephroma.
Clinical exome sequencing (CES) analysis revealed the DICER1 (NM_030621.4): c.1525C>T (p.Arg509Ter) (heterozygous) variant.The variant was classified as pathogenic according to ACMG criteria. Pedigree analysis revealed a history of nephrolithiasis in the mother and maternal grandmother, as well as a family history of kidney tumors in the maternal grandmother's brother's son. Parent segregation analysis showed that the variant was inherited from the healthy father.
Conclusion: DICER1 syndrome is a pleiotropic tumor predisposition disorder caused by pathogenic germline variants in the DICER1 gene, which encodes an endoribonuclease crucial for the processing of microRNAs. DICER1 tumor predisposition is characterized by an increased risk of pleuropulmonary blastoma (PPB), pulmonary cysts, thyroid neoplasms, ovarian tumors, and cystic nephroma. Less common tumors associated with this syndrome include ciliary body medulloepithelioma, nasal chondromesenchymal hamartoma, embryonal rhabdomyosarcoma, pituitary blastoma, pineoblastoma, central nervous system sarcoma, other central nervous system tumors, and presacral malignant teratoid tumors. Most tumors are observed in individuals under the age of 40. DICER1 syndrome is inherited in an autosomal dominant manner with low penetrance. In individuals with DICER1 syndrome who carry pathogenic variants in the germline DICER1 gene, approximately 80% of variants are inherited from one parent, while about 20% are de novo.
Cystic nephroma (CN) is a rare benign kidney tumor characterized by cysts of various sizes within the kidney, accounting for less than 1% of all kidney tumors. It usually presents with an asymptomatic, enlarging abdominal or flank mass.
This study highlights the importance of low penetrance DICER1 gene analysis in patients diagnosed with bilateral cystic nephroma and contributes a new patient to the literature.
Keywords: Bilateral cystic nephroma, DICER1 syndrome, Hereditary cancer syndrome