Sclerosing angiomatoid nodular transformation, a rare splenic tumor with increasing incidence.

SANT (sclerosing angiomatoid nodular transformation) tumor is a rare splenic tumor of unknown etiology and vascular lineage, first described in 2004. Most cases are asymptomatic, although cases of anemia or abdominal pain in association with growth have been described. Spontaneous ruptures have not been described. Radiologically it presents a radial pattern with centripetal filling in dynamic MRI, being a characteristic feature, but not pathognomonic. It may present hypermetabolism in PET-CT. Its incidence is increasing since its description as an independent clinical and histopathological entity, especially in the oncological patients follow-up. Due to its radiological resemblance to metastatic lesions and its growth despite being a vascular lesion, splenectomy is indicated following the principles of oncologic surgery until a definitive diagnosis is made. It presents a benign behavior, requiring neither treatment nor specific subsequent surveillance. Two diagnosed cases of SANT are presented, as well as a review of the clinical, radiological and histopathological characteristics of this little-known splenic lesion.

MicroRNA signature and integrative omics analyses define prognostic clusters and key pathways driving prognosis in patients with neuroendocrine neoplasms.

Neuroendocrine neoplasms (NENs) are mutationally quiet (low number of mutations/Mb), and epigenetic mechanisms drive their development and progression. We aimed at comprehensively characterising the microRNA (miRNA) profile of NENs, and exploring downstream targets and their epigenetic modulation. In total, 84 cancer-related miRNAs were analysed in 85 NEN samples from lung and gastroenteropancreatic (GEP) origin, and their prognostic value was evaluated by univariate and multivariate models. Transcriptomics (N = 63) and methylomics (N = 30) were performed to predict miRNA target genes, signalling pathways and regulatory CpG sites. Findings were validated in The Cancer Genome Atlas cohorts and in NEN cell lines. We identified a signature of eight miRNAs that stratified patients in three prognostic groups (5-year survival of 80%, 66% and 36%). Expression of the eight-miRNA gene signature correlated with 71 target genes involved in PI3K-Akt and TNFα-NF-kB signalling. Of these, 28 were associated with survival and validated in silico and in vitro. Finally, we identified five CpG sites involved in the epigenetic regulation of these eight miRNAs. In brief, we identified an 8-miRNA signature able to predict survival of patients with GEP and lung NENs, and identified genes and regulatory mechanisms driving prognosis in NEN patients.