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81.
P16(INK4a) is a tumor suppressor gene frequently inactivated by aberrant promoter hypermethylation. In this study, p16(INK4a) methylation was evaluated in intraductal proliferative lesions of the breast, using real-time quantitative polymerase chain reaction (MethyLight) and methylation-sensitive restriction endonuclease polymerase chain reaction. Immunohistochemistry was performed to compare and validate the methylation analysis. P16(INK4a) methylation associated with oncogene cyclinD1 expression, detected through the use of in situ hybridization and immunohistochemistry, was likewise characterized. P16(INK4a) methylation displayed varying significance among different types of intraductal proliferative lesions. Both the positive rate and the median quantitative methylation value increased with the evolution of intraductal proliferative lesions through the use of quantitative and qualitative assays. P16(INK4a) methylation was positively correlated to cyclinD1 overexpression. This study demonstrated that p16(INK4a) methylation served as the silencing mechanism of p16(INK4a) protein expression and played a crucial role in the intraductal proliferative lesions' progression. In the differential diagnosis of intraductal proliferative lesions, quantitative DNA methylation analysis of p16(INK4a) by MethyLight may be used as a surrogate, especially to distinguish atypical ductal hyperplasia from usual ductal hyperplasia and low-grade ductal carcinoma in situ. Furthermore, this study discovered that flat epithelial atypia do not share similar molecular profiles of p16(INK4a) epigenetic modification with atypical ductal hyperplasia and low-grade ductal carcinoma in situ. 相似文献
82.
Turashvili G Hayes M Gilks B Watson P Aparicio S 《Virchows Archiv : an international journal of pathology》2008,452(6):589-598
Columnar cell lesions (CCLs) are one of the most common abnormalities in the adult female human breast, characterized by the presence of columnar-shaped epithelial cells lining enlarged terminal-duct lobular units. CCLs are being seen increasingly in core biopsies taken for the non-palpable calcifications. The increased incidence may reflect improved delineation and recognition of CCLs by pathologists or a true increase in incidence related to biological and/or environmental factors. Columnar cell-like lesions have been described under a variety of names such as blunt duct adenosis, flat epithelial atypia, and ductal intraepithelial neoplasia type DIN1a. The current histologic classification used by some pathologists divides them into simple columnar cell change and columnar cell hyperplasia, both of which can occur with or without atypia. Columnar cells lack mature luminal or basal/myoepithelial phenotype markers, but they are usually positive for estrogen receptor-alpha. The cellular origin of CCLs and their possible relationship to either expansion or metaplasia of a preexisting normal cell phenotype remains unclear. CCLs are frequently associated with lobular and ductal in situ tumors and invasive lobular and tubular carcinomas. The relationship and natural history of CCLs to invasive ductal carcinoma is enigmatic, but they may prove of clinical relevance when detected by screening mammography. 相似文献
83.
de Gelder R Fracheboud J Heijnsdijk EA den Heeten G Verbeek AL Broeders MJ Draisma G de Koning HJ 《Preventive medicine》2011,53(3):134-140
Objective
Digital mammography has been shown to increase the detection of ductal carcinoma in situ (DCIS) compared to screen-film mammography. The benefits and risks of such an increase were assessed.Methods
Breast cancer detection rates were compared between 502,574 screen-film and 83,976 digital mammograms performed between 2004 and 2006 among Dutch screening participants. The detection rates were then modeled using a baseline model and two extreme models that respectively assumed a high rate of progression and no progression of preclinical DCIS to invasive cancer. With these models, breast cancer mortality and overdiagnosis were predicted.Results
The DCIS detection rate was significantly higher at digital mammography (1.2 per 1000 mammograms (95% C.I. 1.0-1.5)) than at screen-film mammography (0.7 per 1000 mammograms (95% C.I. 0.6-0.7)). Consequently, 287 (range progressive- non progressive model: 1-598) extra breast cancer deaths per 1,000,000 women (a 4.4% increase) were predicted to be prevented. An extra 401 (range: 165-2271) cancers would be overdiagnosed (a 21% increase).Conclusion
Modeling predicted that digital mammography screening would further reduce breast cancer mortality by 4.4%, at a 21% increased overdiagnosis rate. The consequences of digital screening, however, are sensitive to underlying assumptions on the natural history of DCIS. 相似文献84.
Cone MM Rea JD Diggs BS Douthit MA Billingsley KG Sheppard BC 《American journal of surgery》2011,201(5):575-579
Background
The purpose of this study was to examine the characteristics of pancreatic intraductal papillary mucinous neoplasm (IPMN) in our institution and the selection for resection. Recent publications, including those from the International Consensus Guidelines and the Mayo Clinic, set forth criteria for resection. However, these criteria differ in the definition of main duct IPMN, which is an indication to resect.Methods
Sixty patients from a single institution were retrospectively reviewed between 2000 and 2009.Results
Thirteen percent of patients had high-grade dysplasia, and 22% had invasive cancer. In multivariate analysis, factors associated with a lower risk of carcinoma were female sex (P = .039) and size <3 cm (P = .024). Patients were retrospectively evaluated with Mayo and International Consensus Guidelines. Eight patients had a diagnosis that would have changed from main duct to branch duct if the International Consensus Guidelines were used. Of these 8, there were 2 cancers. If the International Consensus Guidelines were applied instead of the Mayo, both cancers would have been resected, but 2 patients without cancer would have been spared an operation.Conclusions
Twenty-two percent of resected patients had invasive cancer, and they had significantly worse survival (37 vs 85 months, P = .032). In our patient group, application of the International Consensus Guidelines identified all malignant IPMN and would have prevented 2 nontherapeutic resections when compared with the Mayo criteria. 相似文献85.
《Pancreatology》2016,16(5):865-868
BackgroundAbout half of the world population is infected with Helicobacter pylori (H. pylori), a bacterium associated with gastric cancer and considered to be a risk factor for pancreatic ductal adenocarcinoma. Whether the bacterium is associated with intraductal papillary mucinous neoplasm, believed to be a precursor of pancreatic ductal adenocarcinoma, is unknown. The aim of this study was to investigate the presence of H. pylori DNA in tissue sections of intraductal papillary mucinous neoplasm.MethodsThe presence of H. pylori DNA was tested in a retrospective controlled study of formalin-fixed, paraffin-embedded pancreatic tissues from 24 patients who underwent surgery for intraductal papillary mucinous neoplasm. Histologically normal tissues surrounding neoplasms were used as control. H. pylori DNA was evaluated after deparaffinization, DNA extraction, and purification, and results were evaluated statistically.ResultsSamples were collected from 13 males and 11 females with mean age 59 years (range 44–77), and consisted of 19 cases of main-duct and three cases of branched-duct intraductal papillary mucinous neoplasm. Two patients were diagnosed with pancreatic cancer and main-duct intraductal papillary mucinous neoplasm. H. pylori DNA was not detected either in intraductal papillary mucinous neoplasm tissue, or in surrounding normal tissue.ConclusionsAlthough H. pylori has been implicated in pancreatic ductal adenocarcinoma, it may not play a key role in the development of intraductal papillary mucinous neoplasm. 相似文献
86.
BackgroundThe extent of pancreatic resection for intraductal papillary mucinous neoplasms (IPMNs) remains an unresolved issue. The study aims at analyzing the prognostic impact of conservative surgery (CS) i.e. of pancreatoduodenectomy or distal pancreatectomy, versus total pancreatectomy (TP), for pancreatic IPMNs.MethodsWe retrospectively analyzed and compared data of patients who had undergone pancreatic resection for IPMNs at our center between November 2007 and April 2019. Patients were divided into two main groups based on the extent of surgery: TP-group and CS-group. Subsequently, the perioperative and the long-term outcomes were compared. Moreover, a sub-group analysis of patients with IPMN alone and patients with malignant IPMN, based on preoperative indications to surgery and post-operative histopathological findings, was also performed.ResultsFifty-three patients were included in the TP-group and 73 in the CS-group. In 50 (39.7%) cases the frozen section changed the pre-operative surgical planning, with an extension of the pancreatic resection, in 43 (34.1%) cases up to a total pancreatectomy. Twenty-six patients (20.6%) with low-grade dysplasia at the frozen section underwent CS, while twenty (15.8%) underwent TP. Comparing these two sub-groups no differences were found in surgical IPMN recurrence, nor progression. The rate of overall postoperative complications was 56.6% in the TP-group and 57.5% in the CS-group (p = 0.940). Fifteen patients (20.5%) developed diabetes in the CS-group.None of the patients treated with CS developed a surgical IPMN recurrence or progression during the follow-up period. Comparing OS and DFS of the two groups, we did not find any statistically significant difference (p = 0.619 and 0.315).ConclusionA timely CS can be considered an appropriate and valid strategy in the surgical treatment of the majority of pancreatic IPMNs, as it can avoid the serious long-term metabolic consequences of TP in patients with a long-life expectancy. On the contrary, TP remains mandatory in case of PDAC or high-risk features involving the entire gland. 相似文献
87.
《Pancreatology》2020,20(7):1393-1398
IntroductionThe European evidence-based guidelines on PCN recommend surveillance for IPMN patients who are fit for surgery but who have no indication for immediate surgery. Our aim was to demonstrate the feasibility of the new guidelines in clinical practice.MethodsThis is a prospective cohort study of patients included in the IPMN register in Tampere University Hospital, Finland. IPMN was diagnosed from January 1, 2013 to December 31, 2018. Patients were analyzed for surveillance and indications for surgery according to the European guidelines on PCN.ResultsOut of 128 patients in register 23 was decided to operate upfront and 105 patients were included in the surveillance programme. Invasive carcinoma was found in 4/23 of operated patients. Median follow-up time was 26 months (6–69). Median size of the cyst at the beginning and end of the surveillance was 16 mm (4–58 mm). During surveillance 0/105 (0.0%) patients had or developed an absolute indication for surgery. Relative indication for surgery was present in 8/105 (7.6%) patients in the beginning surveillance and 9/105 (8.6%) patients developed at least one relative indication for surgery during surveillance. From the surveillance cohort 2/105 patients were operated. Surveillance was abandoned in 15/105 (14.1%) patients all due to poor general condition or other medical conditions.ConclusionsIn clinical practice, surveillance of IPMN according to the European guidelines on PCN is feasible. Among our patients 16% were detected to have relative indications for surgery during the median 26 (range 3–135) months of surveillance. Nearly 15% became surgically unfit during surveillance period. 相似文献
88.
Marco Del Chiaro Caroline Verbeke 《World journal of gastrointestinal pathophysiology》2015,6(2):29-32
Pancreatic cystic neoplasms(PCNs) are a high prevalence disease. It is estimated that about 20% of the general population is affected by PCNs. Some of those lesions can progress till cancer, while others behave in a benign fashion. In particular intraductal papillary mucinousneoplasms of the pancreas can be considered as the pancreatic analogon to colonic polyps. Treatment of these precursor lesions at an early stage can potentially reduce pancreas cancer mortality and introduce a new "era" of preemptive pancreatic surgery. However, only few of those lesions have an aggressive behavior. The accuracy of preoperative diagnosis, i.e., the distinction between the various PCNs is around 60%, and the ability to predict the future outcome is also less accurate. For this reason, a significant number of patients are currently over-treated with an unnecessary, high-risk surgery. Furthermore, the majority of patients with PCN are on life-long follow-up with imaging modality, which has huge cost implications for the Health Care System for limited benefits considering that a significant proportion of PCNs are or behave like benign lesions. The current guidelines for the diagnosis and management of PCNs are more based on expert opinion than on evidence. For all those reasons, the management of cystic tumors of the pancreas remains a controversial area of pancreatology. On one hand, the detection of PCNs and the surgical treatment of pre-cancerous neoplasms can be considered a big opportunity to reduce pancreatic cancer related mortality. On the other hand, PCNs are associated with a considerable risk of under- or over- treatment of patients and incur high costs for the Health Care System. 相似文献
89.
Luciano Tarantino Giuseppina Busto Aurelio Nasto Riccardo Aurelio Nasto Paolo Tarantino Raffaele Fristachi Luigi Cacace Sara Bortone 《European journal of surgical oncology》2018,44(10):1603-1609
Aim
We evaluated feasibility, safety and efficacy of Electrochemotherapy (ECT) in a prospective series of patients with unresectable Perihilar-Cholangiocarcinoma (PHCCA).Patients and methods
Five patients with PHCCA underwent ECT. Three patients underwent percutaneous ECT of a single PHCCA nodule. One patient underwent resection of a nodule in the IV segment and intraoperative ECT of a large PHCCA in the VIII segment. Another patient underwent percutaneous ECT of a large PHCCA recurrence after left lobectomy and RF ablation of a synchronous metastasis in the VI segment.ECT was performed under US guidance. Efficacy was evaluated by contrast-enhanced multiple-detector-computed-tomography (MDCT) 4 weeks after treatment. Follow-up entailed MDCT every 6 months thereafter.Results
No major complication occurred. Follow-up ranges from 10 to 30 months. Four weeks post-treatment CT showed complete response in 3 cases. These patients are still alive, and follow-up CT controls demonstrated no local or distant intrahepatic recurrences and no biliary duct dilation in 2 cases and local recurrence at 18 months follow-up control in 1 patient. In the remaining 2 cases, 4-weeks-post-treatment CT showed incomplete response (>90%). In these patients follow-up CT demonstrated local progression of the disease at 6 months. One of them had bilateral external biliary drainages and died because of tumor progression at 16-months-follow-up. The other patient, died at 10 months follow-up for cardiovascular failure not related to the hepatobiliary disease.Conclusions
ECT is feasible, safe and effective therapy to improve prognosis and quality of life of patients with unresectable PHCCA. 相似文献90.
Maíra Teixeira Dória Jonathan Yugo Maesaka Raymundo Soares de Azevedo Neto Nestor de Barros Edmund Chada Baracat José Roberto Filassi 《Clinical breast cancer》2018,18(5):e805-e812