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Concept: Dysplasia

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Even though hematopoietic stem cell (HSC) dysfunction is presumed in myelodysplastic syndrome (MDS), the exact nature of quantitative and qualitative alterations is unknown. We conducted a study of phenotypic and molecular alterations in highly fractionated stem and progenitor populations in a variety of MDS subtypes. We observed an expansion of the phenotypically primitive long-term HSCs (lineage(-)/CD34(+)/CD38(-)/CD90(+)) in MDS, which was most pronounced in higher-risk cases. These MDS HSCs demonstrated dysplastic clonogenic activity. Examination of progenitors revealed that lower-risk MDS is characterized by expansion of phenotypic common myeloid progenitors, whereas higher-risk cases revealed expansion of granulocyte-monocyte progenitors. Genome-wide analysis of sorted MDS HSCs revealed widespread methylomic and transcriptomic alterations. STAT3 was an aberrantly hypomethylated and overexpressed target that was validated in an independent cohort and found to be functionally relevant in MDS HSCs. FISH analysis demonstrated that a very high percentage of MDS HSC (92% ± 4%) carry cytogenetic abnormalities. Longitudinal analysis in a patient treated with 5-azacytidine revealed that karyotypically abnormal HSCs persist even during complete morphologic remission and that expansion of clonotypic HSCs precedes clinical relapse. This study demonstrates that stem and progenitor cells in MDS are characterized by stage-specific expansions and contain epigenetic and genetic alterations.

Concepts: Gene, Genetics, Hematology, Syndromes, Acute myeloid leukemia, Virtual Karyotype, Dysplasia, Myelodysplastic syndrome

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Background An accurate, noninvasive test could improve the effectiveness of colorectal-cancer screening. Methods We compared a noninvasive, multitarget stool DNA test with a fecal immunochemical test (FIT) in persons at average risk for colorectal cancer. The DNA test includes quantitative molecular assays for KRAS mutations, aberrant NDRG4 and BMP3 methylation, and β-actin, plus a hemoglobin immunoassay. Results were generated with the use of a logistic-regression algorithm, with values of 183 or more considered to be positive. FIT values of more than 100 ng of hemoglobin per milliliter of buffer were considered to be positive. Tests were processed independently of colonoscopic findings. Results Of the 9989 participants who could be evaluated, 65 (0.7%) had colorectal cancer and 757 (7.6%) had advanced precancerous lesions (advanced adenomas or sessile serrated polyps measuring ≥1 cm in the greatest dimension) on colonoscopy. The sensitivity for detecting colorectal cancer was 92.3% with DNA testing and 73.8% with FIT (P=0.002). The sensitivity for detecting advanced precancerous lesions was 42.4% with DNA testing and 23.8% with FIT (P<0.001). The rate of detection of polyps with high-grade dysplasia was 69.2% with DNA testing and 46.2% with FIT (P=0.004); the rates of detection of serrated sessile polyps measuring 1 cm or more were 42.4% and 5.1%, respectively (P<0.001). Specificities with DNA testing and FIT were 86.6% and 94.9%, respectively, among participants with nonadvanced or negative findings (P<0.001) and 89.8% and 96.4%, respectively, among those with negative results on colonoscopy (P<0.001). The numbers of persons who would need to be screened to detect one cancer were 154 with colonoscopy, 166 with DNA testing, and 208 with FIT. Conclusions In asymptomatic persons at average risk for colorectal cancer, multitarget stool DNA testing detected significantly more cancers than did FIT but had more false positive results. (Funded by Exact Sciences; ClinicalTrials.gov number, NCT01397747 .).

Concepts: DNA, Cancer, Mutation, Oncology, Type I and type II errors, Colorectal cancer, Dysplasia, DNA profiling

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BACKGROUND: Endoscopic ampullectomy is established as a valuable treatment for adenomas of the Vaterian papilla. Few large series are available, however, let alone any with long-term follow-up. Moreover, multiple tangible issues remain. The aim of our study was to evaluate efficacy, safety, and outcome of endoscopic ampullectomy and compare it to existing literature METHODS: This is a single-center, retrospective study with a minimal follow-up of 3 years including 91 patients, including familial adenomatous polyposis (FAP) and non-FAP, who had an endoscopic ampullectomy between 2000 and 2008. Outcome parameters included ampulloma characteristics, biotical accuracy as well as safety, efficacy, recurrence rate, and survival after endoscopic ampullectomy. RESULTS: Endoscopic resection was successful in 71 patients (78 %). Histological review of the resected specimens revealed nonspecific changes (13.8 %), low or medium grade dysplasia (52.9 %), high grade dysplasia (21.8 %) and carcinoma (18.3 %). Bioptic accuracy was 38.3 %. Overall complications were observed in 23 patients (25.2 %): pancreatitis (15.4 %), hemorrhage (12.1 %) and cholangitis (4.9 %). Recurrence occurred in 18.3 %. Fourteen patients underwent pancreaticoduodenectomy. Survival after complete endoscopic ampullectomy was excellent for patients with low to moderate grade dysplasia and high grade dysplasia. Incomplete endoscopic resection of high grade dysplasia or invasive carcinoma was associated with unfavorable outcome when treated merely endoscopically. CONCLUSIONS: Endoscopic ampullectomy is obligatory for assessment of the true histological nature of an ampulloma. Endoscopic resection is a safe and efficient procedure for adenomas with low to moderate dysplasia but also for high grade dysplastic lesions, provided that a complete endoscopic resection is achieved.

Concepts: Cohort study, Cancer, Oncology, Carcinoma in situ, Anatomical pathology, Adenocarcinoma, Familial adenomatous polyposis, Dysplasia

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Background and study aim Cryoablation can be used for the treatment of Barrett’s esophagus (BE). A recent dosimetry study, using the CryoBalloon Focal Ablation System (CryoBalloon), demonstrated that 10-second ablations result in complete eradication of BE. However, the efficacy of 10-second ablation in a larger cohort of patients has not been investigated, nor has the potential of precise targeting of specific areas. The aim of the study was to assess the efficacy and performance (i. e. targeting of BE islands) of a 10-second cryoablation using the CryoBalloon. Results A total of 30 patients were enrolled (worst pathology: low grade dysplasia in 14 [47 %], high grade dysplasia in 7 [23 %], early adenocarcinoma in 9 [30 %]). Of the 47 BE islands, 44 (94 %) were adequately targeted. Complete eradication of intestinal metaplasia and dysplasia was observed in 100 % of the completely ablated areas. No stenoses were observed. Conclusion Cryoablation of BE islands using the CryoBalloon is effective. BE islands were effectively targeted.

Concepts: Cancer, Histopathology, Gastroenterology, Dysplasia, Esophageal cancer, Barrett's esophagus, Metaplasia, Ablation

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Barrett esophagus containing low-grade dysplasia is associated with an increased risk of developing esophageal adenocarcinoma, a cancer with a rapidly increasing incidence in the western world.

Concepts: Epidemiology, Clinical trial, Gastroesophageal reflux disease, Western world, Western culture, Dysplasia, Esophageal cancer, Barrett's esophagus

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The long-term effectiveness of the quadrivalent human papillomavirus (qHPV) vaccine was assessed by monitoring the combined incidence of cervical intraepithelial neoplasia (CIN2, CIN3), adenocarcinoma in situ (AIS), and cervical cancer related to HPV16 or HPV18.

Concepts: Oncology, Cervical intraepithelial neoplasia, Human papillomavirus, Cervical cancer, Carcinoma in situ, Papillomavirus, HPV vaccine, Dysplasia

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Evidence for distinct human cancer stem cells (CSCs) remains contentious and the degree to which different cancer cells contribute to propagating malignancies in patients remains unexplored. In low- to intermediate-risk myelodysplastic syndromes (MDS), we establish the existence of rare multipotent MDS stem cells (MDS-SCs), and their hierarchical relationship to lineage-restricted MDS progenitors. All identified somatically acquired genetic lesions were backtracked to distinct MDS-SCs, establishing their distinct MDS-propagating function in vivo. In isolated del(5q)-MDS, acquisition of del(5q) preceded diverse recurrent driver mutations. Sequential analysis in del(5q)-MDS revealed genetic evolution in MDS-SCs and MDS-progenitors prior to leukemic transformation. These findings provide definitive evidence for rare human MDS-SCs in vivo, with extensive implications for the targeting of the cells required and sufficient for MDS-propagation.

Concepts: Cancer, Human, Mutation, Stem cell, Stem cells, The Canon of Medicine, Dysplasia, Myelodysplastic syndrome

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Barrett’s esophagus (BE) is a common premalignant lesion for which surveillance is recommended. This strategy is limited by considerable variations in clinical practice. We conducted an international, multidisciplinary, systematic search and evidence-based review of BE and provided consensus recommendations for clinical use in patients with nondysplastic, indefinite, and low-grade dysplasia (LGD).

Concepts: Clinical trial, Hospital, Evidence-based medicine, Dysplasia, Esophageal cancer, Barrett's esophagus, Metaplasia

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Background Although colonoscopic surveillance of patients after removal of adenomas is widely promoted, little is known about colorectal-cancer mortality among these patients. Methods Using the linkage of the Cancer Registry and the Cause of Death Registry of Norway, we estimated colorectal-cancer mortality among patients who had undergone removal of colorectal adenomas during the period from 1993 through 2007. Patients were followed through 2011. We calculated standardized incidence-based mortality ratios (SMRs) using rates for the Norwegian population at large for comparison. Norwegian guidelines recommended colonoscopy after 10 years for patients with high-risk adenomas (adenomas with high-grade dysplasia, a villous component, or a size ≥10 mm) and after 5 years for patients with three or more adenomas; no surveillance was recommended for patients with low-risk adenomas. Polyp size and exact number were not available in the registry. We defined high-risk adenomas as multiple adenomas and adenomas with a villous component or high-grade dysplasia. Results We identified 40,826 patients who had had colorectal adenomas removed. During a median follow-up of 7.7 years (maximum, 19.0), 1273 patients were given a diagnosis of colorectal cancer. A total of 398 deaths from colorectal cancer were expected and 383 were observed, for an SMR of 0.96 (95% confidence interval [CI], 0.87 to 1.06) among patients who had had adenomas removed. Colorectal-cancer mortality was increased among patients with high-risk adenomas (expected deaths, 209; observed deaths, 242; SMR, 1.16; 95% CI, 1.02 to 1.31), but it was reduced among patients with low-risk adenomas (expected deaths, 189; observed deaths, 141; SMR, 0.75; 95% CI, 0.63 to 0.88). Conclusions After a median of 7.7 years of follow-up, colorectal-cancer mortality was lower among patients who had had low-risk adenomas removed and moderately higher among those who had had high-risk adenomas removed, as compared with the general population. (Funded by the Norwegian Cancer Society and others.).

Concepts: Cancer, Oncology, Demography, Colorectal cancer, Colon, Adenocarcinoma, Normal distribution, Dysplasia

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Telomere end-to-end fusions are an important source of chromosomal instability that arise in cells with critically shortened telomeres. We developed a nested real-time quantitative PCR method for telomere fusion detection in pancreatic ductal adenocarcinomas, intraductal papillary mucinous neoplasms (IPMNs), and IPMN cyst fluids. Ninety-one pancreatic cancer cell lines and xenograft samples, 93 IPMNs, and 93 surgically aspirated IPMN cyst fluid samples were analyzed. The association between telomere shortening, telomerase activity, and telomere fusion detection was evaluated. Telomere fusions were detected in 56 of 91 pancreatic cancers (61.5%). Telomere fusion-positive cell lines had significantly shorter telomere lengths than fusion-negative lines (P = 0.003). Telomere fusions were undetectable in normal pancreas or IPMNs with low-grade dysplasia (0.0%) and were detected in IPMN with high-grade dysplasia (HGD; 48.0%) (P < 0.001). In IPMN cyst fluids, telomere fusions were more frequent in IPMNs with HGD (26.9%) or associated invasive cancer (42.9%) than IPMN with intermediate-grade dysplasia (15.4%) or low-grade dysplasia (0%) (P = 0.025). Telomerase activity levels were higher in cyst fluids with fusions than in those without (P = 0.0414). Cyst fluid telomere fusion status was an independent predictor of HGD/invasive cancer by multivariate analysis (odds ratio, 6.23; 95% CI, 1.61-28.0). Telomere fusions are detected in later stages of IPMN progression and can serve as a marker for predicting the presence of HGD and/or invasive cancer.

Concepts: Cancer, Senescence, DNA replication, Telomerase, Telomere, Intraductal papillary mucinous neoplasm, Pancreatic cancer, Dysplasia