Cell-Free DNA From Metastatic Pancreatic Neuroendocrine Tumor Patients Contains Tumor-Specific Mutations and Copy Number Variations

Background: Detection of tumor-specific alterations in cell-free DNA (cfDNA) has proven valuable as a liquid biopsy for several types of cancer. So far, use of cfDNA remains unexplored for pancreatic neuroendocrine tumor (PNET) patients.Methods: From 10 PNET patients, fresh frozen tumor tissue, buffy coat and plasma samples were collected. Whole-exome sequencing of primary tumor and germline DNA was performed to identify tumor-specific variants and copy number variations (CNVs). Subsequently, tumor-specific variants were quantified in plasma cfDNA with droplet digital PCR. In addition, CNV analysis of cfDNA was performed using shallow whole-genome sequencing.Results: Tumor-specific variants were detected in perioperative plasma samples of two PNET patients, at variant allele fractions (VAFs) of respectively 19 and 21%. Both patients had metastatic disease at time of surgery, while the other patients presented with localized disease. In the metastatic patients, CNV profiles of tumor tissue and cfDNA were significantly correlated. A follow-up plasma sample of a metastatic patient demonstrated an increased VAF (57%) and an increased chromosomal instability, in parallel with an increase in tumor burden.Conclusions: We are the first to report the presence of tumor-specific genetic alterations in cfDNA of metastatic PNET patients and their evolution during disease progression. Additionally, CNV analysis in cfDNA shows potential as a liquid biopsy

The genus Eunotia on the volcanic island Ile Amsterdam (TAAF, southern Indian ocean).

International audienceDuring a preliminary survey of the non-marine diatom flora of the volcanic island, Île Amsterdam (southern Indian Ocean), five species belonging to the genus Eunotia have been found. Apart from Eunotia paludosa var. paludosa and E. muscicola var. muscicola, three appear to be new to science and are described as E. pugilistica Van de Vijver sp. nov., E. lecohui Van de Vijver sp. nov. and E. cocquytiae sp. nov. All species are fully investigated using both LM and SEM techniques. The new taxa are compared with similar species. Notes on their ecology and associated diatom communities are added. Finally, the biogeographical position of Île Amsterdam based on the genus Eunotia is briefly discussed

Rethinking end-of-life care and palliative care : learning from the illness trajectories and lived experiences of terminally ill patients and their family carers

Lynn conceptualized end-of-life (EoL) care for patients with advanced chronic-progressive illnesses as a combination of life-preserving/palliative care, the palliative aspect gradually becoming the main focus as death approaches. We checked this concept by exploring the advanced-terminal illness trajectories of 50 patients. Strategies heralding active therapy exhaustion were the catalyst for a participant's awareness of terminality, but were not a decisive factor in the divergent EoL care pathways we detected. The terms life-preserving and palliative do not adequately capture EoL care pathways due to their conceptual ambiguity. Conversely, the concept of EoL care encompassing three palliative care modalities (life-prolonging palliative therapy, restorative palliative care, and symptom-oriented [only] palliative care), each harboring a different blend of life-preserving and symptom-comforting aspects, proved adequate. These modalities could run serially, oscillatorily, or parallelly, explaining the divergent EoL care pathways. We suggest an adjustment of the model of Lynn and reconsider the traditional palliative care concept