Expanded phenotype and cancer risk in patients with Beckwith-Wiedemann spectrum caused by CDKN1C variants.

Beckwith-Wiedemann spectrum (BWSp) is caused by genetic and epigenetic alterations on chromosome 11 that regulate cell growth and division. Considering the diverse phenotypic landscape in BWSp, the characterization of the CDKN1C molecular subtype remains relatively limited. Here, we investigate the role of CDKN1C in the broader BWSp phenotype. Notably, patients with CDKN1C variants appear to exhibit a different tumor risk than other BWSp molecular subtypes. We performed a comprehensive literature review using the search term "CDKN1C Beckwith" to identify 113 cases of patients with molecularly confirmed CDKN1C-BWSp. We then assessed the genotype and phenotype in a novel cohort of patients with CDKN1C-BWSp enrolled in the BWS Research Registry. Cardinal and suggestive features were evaluated for all patients reported, and tumor risk was established based on available reports. The most common phenotypes included macroglossia, omphalocele, and ear creases/pits. Tumor types reported from the literature included neuroblastoma, acute lymphocytic leukemia, superficial spreading melanoma, and intratubular germ cell neoplasia. Overall, this study identifies unique features associated with CDKN1C variants in BWSp, enabling more accurate clinical management. The absence of Wilms tumor and hepatoblastoma suggests that screening for these tumors may not be necessary, while the neuroblastoma risk warrants appropriate screening recommendations.

A single-centre experience with tumour tract seeding associated with needle manipulation of renal cell carcinomas.

With the rise in detection of incidental renal masses on imaging, there has been a commensurate rise in the use of percutaneous biopsies for evaluation of these tumours. Tumour tract seeding had previously been one of the most feared complications of percutaneous biopsy of renal cell carcinoma (RCC). Recently, less emphasis has been placed on this complication, with the assertion that it has only been reported eight times in literature, and thus must be exceedingly rare. However, we report two cases of tumour tract seeding associated with percutaneous biopsy and treatment of RCC over a short time period at a single institution. This report challenges the current extremely low estimates of the frequency of this complication and calls for a more realistic assessment.