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Intraductal papillary mucinous neoplasm of the pancreas: cytologic features predict histologic grade
BACKGROUND: Intraductal papillary mucinous neoplasm (IPMN) is an increasingly recognized cystic neoplasm of the pancreas, histologically classified by the degree of epithelial atypia and by the presence or absence of invasion of the cyst wall. To the authors' knowledge, the cytologic features of this neoplasm are poorly characterized, especially with respect to tumor grade. METHODS: Thirty-three endoscopic ultrasound (EUS)-guided pancreatic fine-needle aspiration biopsy (FNAB) samples and 1 pancreatic duct brush specimen from 25 patients with a histologically confirmed IPMN were retrospectively reviewed. Blinded to tumor grade, background mucin, inflammation, necrosis, overall cellularity, the presence of gastrointestinal-contaminating epithelium, architecture of cell clusters, and nuclear and cellular morphology were evaluated. In cases in which special stains for mucin were performed, the diagnostic utility of these stains was assessed. These cytologic features were subsequently correlated with the histologic diagnosis. RESULTS: The 34 cytology samples represented 4 adenomas, 15 IPMN-moderate dysplasias, 7 intraductal carcinomas, and 8 IPMNs with invasive carcinoma. Extracellular mucin was present in 97% of all cases; 53% had thick, viscous, "colloid-like" mucin. Special stains for mucin were positive in 6 of 11 cases (54%), helping to identify thin mucin in only 2 cases. Gastrointestinal contamination did not appear to create diagnostic difficulty due to an apparent dual (dysplastic-nondysplastic) epithelial population, but only 4 adenomas were evaluated in this study. Necrosis distinguished IPMN with carcinoma from IPMN-adenomas and IPMN with moderate dysplasia (P < .00001), and was more often observed with invasion than IPMN-carcinoma in situ (P < .05). Tight epithelial cell clusters with hyperchromatic nuclei and a high nuclear to cytoplasmic ratio was more significant in IPMN of at least moderate dysplasia (P = .03). Pale nuclei with parachromatin clearing was found to be a nuclear feature that was suspicious for at least carcinoma in situ (P < .001). In addition, significant background inflammation (neutrophils and histiocytes) was found to be more characteristic of IPMN with at least carcinoma in situ (P = .002). CONCLUSIONS: The presence of thick, "colloid-like" mucin is noted in half of the IPMN cases, but was not found to be specific to grade. The absence of such mucin does not exclude an IPMN. The presence of tight epithelial cell clusters is consistent with a neoplasm of at least moderate dysplasia, and abundant background inflammation and parachromatin clearing correlated with the presence of at least carcinoma in situ. Necrosis was the only feature found to be strongly suggestive of invasion. 相似文献
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Grootscholten C Ligtenberg G Hagen EC van den Wall Bake AW de Glas-Vos JW Bijl M Assmann KJ Bruijn JA Weening JJ van Houwelingen HC Derksen RH Berden JH;Dutch Working Party on Systemic Lupus Erythematosus 《Kidney international》2006,70(4):732-742
Until recently, intravenous cyclophosphamide pulses with oral corticosteroids were regarded standard therapy for proliferative lupus nephritis (LN). Azathioprine, a less toxic alternative, was never proven to be inferior. In the first Dutch lupus nephritis study (enrollment between 1995 and 2001), we randomized 87 proliferative LN patients to either cyclophosphamide pulses (750 mg/m(2), 13 pulses in 2 years) combined with oral prednisone (CY) or to azathioprine (2 mg/kg/day in 2 years) combined with intravenous pulses of methylprednisolone (3 x 3 pulses of 1000 mg) and oral prednisone (AZA). After a median follow-up of 5.7 years (interquartile range 4.1-7.2 years), doubling of serum creatinine was more frequent in the AZA group, although not statistically significant (relative risk (RR): 4.1, with 95% confidence interval (95% CI): 0.8-20.4). Relapses occurred more often in the AZA group (RR: 8.8, 95% CI: 1.5-31.8). Creatinine and proteinuria at last visit did not differ between the two treatment arms. Moreover, 88.4% of the patients in the AZA arm were still free of cyclophosphamide treatment. During the first 2 years, the frequency of remission was not different, but infections, especially herpes zoster virus infections (HZV) were more frequent in the AZA group. Parameters for ovarian function did not differ between the two groups. In conclusion, in this open-label randomized controlled trial, cyclophosphamide was superior to azathioprine with regard to renal relapses and HZV. At last follow-up, there were no differences in serum creatinine or proteinuria between the two groups. However, since our study lacked sufficient power, longer follow-up is needed to reveal putative differences. 相似文献
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R.H.W.M. Derksen A. van de Wiel J. Poortman P.J. der Kinderen L. Kater 《European journal of obstetrics, gynecology, and reproductive biology》1984,18(3):139-148
Three female patients with severe thyrotoxicosis, two of them pregnant 22 and 16 wk, respectively, were treated with plasma-exchange (PE) combined with anti-thyroid drugs. In both pregnant patients PE was an effective adjunct to therapy with low-dose carbimazol. They were both delivered of normal babies at 37 and 40 wk, respectively. One newborn was euthyroid, the other had transient neonatal thyrotoxicosis. In the non-pregnant patient an ominous situation of thyrotoxic crisis was rapidly reversed by a single PE. During PE an influx of thyroid hormones occurs from the extra- to the intravascular compartment, which increases the efficacy of PE. The 5% albumin solution derived from human donor plasma, used as replacement fluid, contained substantial amounts of thyroid hormones. A 5% albumin solution from human placental origin lacks these hormones and is therefore recommended as replacement fluid for PE in thyrotoxicosis. There are no valid arguments for advocating replacement with donor plasma. 相似文献
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According to the 'acquired preparedness model,' expectancies mediate the relationship between an impulsive personality style and alcohol use. The current study evaluated whether the model can also be applied to marijuana use. Estimated probabilities and subjective evaluations of personally expected marijuana effects, along with impulsivity and frequency of marijuana use, were assessed in 337 college undergraduates. Tests of mediation examining positive and negative marijuana expectancies showed negative expectancies to be a significant mediator for both males and females. That is, participants who were higher on impulsivity had fewer negative expectancies and in turn used more marijuana. This study provides evidence that the acquired preparedness model may help to explain marijuana use. 相似文献