| 1. |
- Karam, Elias, et al.
(author)
-
Endoscopic and Surgical Management of Non-Metastatic Ampullary Neuroendocrine Neoplasia : A Multi-Institutional Pancreas2000/EPC Study
- 2023
-
In: Neuroendocrinology. - 0028-3835. ; 113:10, s. 1024-1034
-
Journal article (peer-reviewed)abstract
- Introduction: Ampullary neuroendocrine neoplasia (NEN) is rare and evidence regarding their management is scarce. This study aimed to describe clinicopathological features, management, and prognosis of ampullary NEN according to their endoscopic or surgical management. Methods: From a multi-institutional international database, patients treated with either endoscopic papillectomy (EP), transduodenal surgical ampullectomy (TSA), or pancreaticoduodenectomy (PD) for ampullary NEN were included. Clinical features, post-procedure complications, and recurrences were assessed. Results: 65 patients were included, 20 (30.8%) treated with EP, 19 (29.2%) with TSA, and 26 (40%) with PD. Patients were mostly asymptomatic (n = 46; 70.8%). Median tumor size was 17 mm (12-22), tumors were mostly grade 1 (70.8%) and pT2 (55.4%). Two (10%) EP resulted in severe American Society for Gastrointestinal Enterology (ASGE) adverse post-procedure complications and 10 (50%) were R0. Clavien 3-5 complications did not occur after TSA and in 4, including 1 postoperative death (15.4%) of patients after PD, with 17 (89.5%) and 26 R0 resection (100%), respectively. The pN1/2 rate was 51.9% (n = 14) after PD. Tumor size larger than 1 cm (i.e., pT stage >1) was a predictor for R1 resection (p < 0.001). Three-year overall survival and disease-free survival after EP, TSA, and PD were 92%, 68%, 92% and 92%, 85%, 73%, respectively. Conclusion: Management of ampullary NEN is challenging. EP should not be performed in lesions larger than 1 cm or with a endoscopic ultrasonography T stage beyond T1. Local resection by TSA seems safe and feasible for lesions without nodal involvement. PD should be preferred for larger ampullary NEN at risk of nodal metastasis.
|
|
| 3. |
- van Leeuwen, F., et al.
(author)
-
Gaia Data Release 1 : Open cluster astrometry: Performance, limitations, and future prospects
- 2017
-
In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 601
-
Journal article (peer-reviewed)abstract
- Context. The first Gaia Data Release contains the Tycho-Gaia Astrometric Solution (TGAS). This is a subset of about 2 million stars for which, besides the position and photometry, the proper motion and parallax are calculated using Hipparcos and Tycho-2 positions in 1991.25 as prior information. Aims. We investigate the scientific potential and limitations of the TGAS component by means of the astrometric data for open clusters. Methods. Mean cluster parallax and proper motion values are derived taking into account the error correlations within the astrometric solutions for individual stars, an estimate of the internal velocity dispersion in the cluster, and, where relevant, the effects of the depth of the cluster along the line of sight. Internal consistency of the TGAS data is assessed. Results. Values given for standard uncertainties are still inaccurate and may lead to unrealistic unit-weight standard deviations of least squares solutions for cluster parameters. Reconstructed mean cluster parallax and proper motion values are generally in very good agreement with earlier Hipparcos-based determination, although the Gaia mean parallax for the Pleiades is a significant exception. We have no current explanation for that discrepancy. Most clusters are observed to extend to nearly 15 pc from the cluster centre, and it will be up to future Gaia releases to establish whether those potential cluster-member stars are still dynamically bound to the clusters. Conclusions. The Gaia DR1 provides the means to examine open clusters far beyond their more easily visible cores, and can provide membership assessments based on proper motions and parallaxes. A combined HR diagram shows the same features as observed before using the Hipparcos data, with clearly increased luminosities for older A and F dwarfs.
|
|
