Background
Incisional hernia is the most frequent long‐term complication after visceral surgery, with an incidence of between 9 and 20 per cent 1 year after operation. Most controlled studies provide ...only short‐term follow‐up, and the actual incidence remains unclear. This study evaluated the incidence of incisional hernia up to 3 years after midline laparotomy in two prospective trials.
Methods
Three‐year follow‐up data from the ISSAAC (prospective, multicentre, historically controlled) and INSECT (randomized, controlled, multicentre) trials focused on the rate of incisional hernia 1 and 3 years after surgery. Differences between the two groups were compared using t tests for continuous data and the χ2 test for categorical data.
Results
Analysis of 775 patients included in the two trials suggested that the incisional hernia rate increased significantly from 12·6 per cent at 1 year to 22·4 per cent 3 years after surgery (P < 0.001), a relative increase of more than 60 per cent.
Conclusion
This follow‐up of two trials demonstrated that 1 year of clinical follow‐up for detection of incisional hernia is not sufficient; follow‐up for at least 3 years should be mandatory in any study evaluating the rate of postoperative incisional hernia after midline laparotomy.
Hernias often occur late
Background Anastomotic leakage represents a major complication after anterior resection of the rectum. The incidence of anastomotic leakage varies considerably among clinical studies in part owing to ...the lack of a standardized definition of this complication. The aim of the present article was to propose a definition and severity grading of anastomotic leakage after anterior rectal resection. Methods After a literature review a consensus definition and severity grading of anastomotic leakage was developed within the International Study Group of Rectal Cancer. Results Anastomotic leakage should be defined as a defect of the intestinal wall at the anastomotic site (including suture and staple lines of neorectal reservoirs) leading to a communication between the intra- and extraluminal compartments. Severity of anastomotic leakage should be graded according to the impact on clinical management. Grade A anastomotic leakage results in no change in patients’ management, whereas grade B leakage requires active therapeutic intervention but is manageable without re-laparotomy. Grade C anastomotic leakage requires re-laparotomy. Conclusion The proposed definition and clinical grading is applicable easily in the setting of clinical studies. It should be applied in future reports to facilitate valid comparison of the results of different studies.
We present infrared observations of 66 starburst galaxies over the full range of oxygen abundances observed in local star-forming galaxies, from image to 8.9. The data include imaging and ...spectroscopy from the Spitzer Space Telescope, supplemented by ground-based near-infrared imaging. We confirm a strong correlation of aromatic emission with metallicity, with a threshold at image. We show that the far-infrared color temperature of the large dust grains increases toward lower metallicity, peaking at a metallicity of 8 before turning over. We compute dust masses and compare them to H i masses from the literature to derive the ratio of atomic gas to dust, which increases by nearly 3 orders of magnitude between solar metallicity and a metallicity of 8, below which it flattens out. The abrupt change in aromatic emission at mid-infrared wavelengths thus appears to be reflected in the far-infrared properties, indicating that metallicity changes affect the composition of the full range of dust grain sizes that dominate the infrared emission. Although the great majority of galaxies show similar patterns of behavior as described above, there are three exceptions, SBS 0335-052E, Haro 11, and SHOC 391. Their infrared SEDs are dominated energetically by the mid- IR near 24 mum rather than by the 60-200 mum region. In addition, they have very weak near-infrared outputs and their SEDs are dominated by emission by dust at wavelengths as short as 1.8 mum. The latter behavior indicates that the dominant star-forming episodes in them are extremely young. The component of the ISM responsible for the usual far-infrared emission appears to be either missing or inefficiently heated in these three galaxies.
We aimed to determine the long-term yield of pancreatic cancer surveillance in hereditary predisposed high-risk individuals.
From 2006 to 2019, we prospectively enrolled asymptomatic individuals with ...an estimated 10% or greater lifetime risk of pancreatic ductal adenocarcinoma (PDAC) after obligatory evaluation by a clinical geneticist and genetic testing, and subjected them to annual surveillance with both endoscopic ultrasonography (EUS) and MRI/cholangiopancreatography (MRI/MRCP) at each visit.
366 individuals (201 mutation-negative familial pancreatic cancer (FPC) kindreds and 165 PDAC susceptibility gene mutation carriers; mean age 54 years, SD 9.9) were followed for 63 months on average (SD 43.2). Ten individuals developed PDAC, of which four presented with a symptomatic interval carcinoma and six underwent resection. The cumulative PDAC incidence was 9.3% in the mutation carriers and 0% in the FPC kindreds (p<0.001). Median PDAC survival was 18 months (range 1-32). Surgery was performed in 17 individuals (4.6%), whose pathology revealed 6 PDACs (3 T1N0M0), 7 low-grade precursor lesions, 2 neuroendocrine tumours <2 cm, 1 autoimmune pancreatitis and in 1 individual no abnormality. There was no surgery-related mortality. EUS detected more solid lesions than MRI/MRCP (100% vs 22%, p<0.001), but less cystic lesions (42% vs 83%, p<0.001).
The diagnostic yield of PDAC was substantial in established high-risk mutation carriers, but non-existent in the mutation-negative proven FPC kindreds. Nevertheless, timely identification of resectable lesions proved challenging despite the concurrent use of two imaging modalities, with EUS outperforming MRI/MRCP. Overall, surveillance by imaging yields suboptimal results with a clear need for more sensitive diagnostic markers, including biomarkers.
Background
In the recent International Study Group of Pancreatic Surgery (ISGPS) consensus on extended pancreatectomy, several issues on perioperative outcome and long‐term survival remained unclear. ...Robust data on outcomes are sparse. The present study aimed to assess the outcome of extended pancreatectomy for borderline resectable and locally advanced pancreatic cancer.
Methods
A consecutive series of patients with primary pancreatic adenocarcinoma undergoing extended pancreatectomies, as defined by the new ISGPS consensus, were compared with patients who had a standard pancreatectomy. Univariable and multivariable analysis was performed to identify risk factors for perioperative mortality and characteristics associated with survival. Long‐term outcome was assessed by means of Kaplan–Meier analysis.
Results
The 611 patients who had an extended pancreatectomy had significantly greater surgical morbidity than the 1217 patients who underwent a standard resection (42·7 versus 34·2 per cent respectively), and higher 30‐day mortality (4·3 versus 1·8 per cent) and in‐hospital mortality (7·5 versus 3·6 per cent) rates. Operating time of 300 min or more, extended total pancreatectomy, and ASA fitness grade of III or IV were associated with increased in‐hospital mortality in multivariable analysis, whereas resections involving the colon, portal vein or arteries were not. Median survival and 5‐year overall survival rate were reduced in patients having extended pancreatectomy compared with those undergoing a standard resection (16·1 versus 23·6 months, and 11·3 versus 20·6 per cent, respectively). Older age, G3/4 tumours, two or more positive lymph nodes, macroscopic positive resection margins, duration of surgery of 420 min or above, and blood loss of 1000 ml or more were independently associated with decreased overall survival.
Conclusion
Extended resections are associated with increased perioperative morbidity and mortality, particularly when extended total pancreatectomy is performed. Favourable long‐term outcome is achieved in some patients.
Considerable morbidity and mortality in some long term survivors
ABSTRACT The polycyclic aromatic hydrocarbon (PAH) emission observed in the Spitzer Infrared Spectrograph spectra of bright mid-IR locations of NGC 7023, NGC 2023, and NGC 1333 was analyzed. These ...objects show large variations in PAH band ratios when studied through spectral mapping. Nevertheless, the mid-IR spectra at these bright spots show a remarkably similar PAH emission. We used the NASA Ames PAH IR Spectroscopic Database to fit the observations and analyze the derived PAH populations. Our results show that PAH emission in the 5-15 m range appears to be rather insensitive to variations of the radiation field. Similar PAH populations of neutral small to medium-sized PAHs (∼50%), with ionized species contributing in slightly less than 50%, provide very good fits. Analyzing the degeneracy of the results shows that subtle (but intrinsic) variations in the emission properties of individual PAHs lead to observable differences in the resulting spectra. On top of this, we found that variations of <30% in the PAH abundances would lead to noticeable spectral differences between the three photodissociation regions (PDRs). Therefore, PAH populations must be remarkably similar at these different lines of sight. To account for this, we suggest the concept of grandPAHs as a unique mixture of the most stable PAHs emitting at these spots. Using NGC 7023 as an example, the grandPAHs refer to the robust PAH population that results from the intense processing of PAHs at the border limit between the PDR and the molecular cloud, where, due to the UV radiation that destroys the PAH population, the abundance of PAHs starts decreasing as we move toward the star.
ABSTRACT
We present dual-band
Herschel
/PACS imaging for 59 main-sequence stars with known warm dust (
T
warm
∼ 200 K), characterized by
Spitzer
. Of 57 debris disks detected at
Herschel
wavelengths ...(70 and/or 100 and 160
μ
m), about half have spectral energy distributions (SEDs) that suggest two-ring disk architectures mirroring that of the asteroid–Kuiper Belt geometry; the rest are consistent with single belts of warm, asteroidal material.
Herschel
observations spatially resolve the outer/cold dust component around 14 A-type and 4 solar-type stars with two-belt systems, 15 of which for the first time. Resolved disks are typically observed with radii >100 AU, larger than expected from a simple blackbody fit. Despite the absence of narrow spectral features for ice, we find that the shape of the continuum, combined with resolved outer/cold dust locations, can help constrain the grain size distribution and hint at the dust’s composition for each resolved system. Based on the combined
Spitzer
/IRS+Multiband Imaging Photometer (5-to-70
μ
m) and
Herschel
/PACS (70-to-160
μ
m) data set, and under the assumption of idealized spherical grains, we find that over half of resolved outer/cold belts are best fit with a mixed ice/rock composition. Minimum grain sizes are most often equal to the expected radiative blowout limit, regardless of composition. Three of four resolved systems around the solar-type stars, however, tend to have larger minimum grains compared to expectation from blowout (
f
MB
=
a
min
/
a
BOS
∼ 5). We also probe the disk architecture of 39
Herschel
-unresolved systems by modeling their SEDs uniformly, and find them to be consistent with 31 single- and 8 two-belt debris systems.
Background
The incidence of pancreatic neuroendocrine neoplasms (pNEN) is increasing. This study aimed to evaluate predictors of overall survival and the indication for surgery.
Methods
Data ...collected between October 2001 and December 2012 were analysed. Histological grading and staging was based on the classifications of the World Health Organization, the International Union Against Cancer and the European Neuroendocrine Tumour Society.
Results
Some 310 patients (150 female, 48·4 per cent) underwent surgical resection. The final survival analysis included 291 patients. Five‐year overall survival differed according to tumour grade (G): 91·0 per cent among 156 patients with pancreatic neuroendocrine tumours (pNET) G1, 70·8 per cent in 111 patients with pNET G2, and 20 per cent in 24 patients with pancreatic neuroendocrine carcinomas (pNEC) G3 (P < 0·001). Tumours graded G3 (hazard ratio (HR) 6·96, 95 per cent confidence interval 3·67 to 13·21), the presence of distant metastasis (HR 2·41, 1·32 to 4·42) and lymph node metastasis (HR 2·10, 1·07 to 4·16) were independent predictors of worse survival (P < 0·001, P = 0·004 and P = 0·032 respectively). Eight of 61 asymptomatic patients with pNEN smaller than 2 cm had tumours graded G2 or G3, and six of 51 patients had lymph node metastasis. Among patients with pNEC G3, the presence of distant metastasis had a significant impact on the 5‐year overall survival rate: 0 per cent versus 43 per cent in those without distant metastasis (P = 0·036).
Conclusion
Neuroendocrine tumours graded G3, lymph node and distant metastasis are independent predictors of worse overall survival in patients with pNEN.
Small tumours are sometimes nasty
We examine colors from 3.6 to 24 mu m as a function of metallicity (O/H) for a sample of 34 galaxies. The galaxies range over 2 orders of magnitude in metallicity. They display an abrupt shift in the ...8 mu m-to-24 mu m color for metallicities between one-third and one-fifth of the solar value. The mean 8-to-24 mu m flux density ratio below and above 12 + log (O/H) = 8.2 is 0.08 plus or minus 0.04 and 0.70 plus or minus 0.53, respectively. We use mid-IR colors and spectroscopy to demonstrate that the shift is primarily due to a decrease in the 8 mu m flux density, as opposed to an increase in the 24 mu m flux density. This result is most simply interpreted as being due to a weakening at low metallicity of the mid-IR emission bands usually attributed to PAHs (polycyclic aromatic hydrocarbons) relative to the small-grain dust emission. However, existing empirical spectral energy distribution models cannot account for the observed short-wavelength (below 8 mu m) colors of the low-metallicity galaxies merely by reducing the strength of the PAH features; some other emission source (e.g., hot dust) is required.
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