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Vito D Corleto

Publications and source records attributed to Vito D Corleto.

7 recordsLinked to original sources
PubMed2005

Is colonoscopy sufficient for colorectal cancer surveillance in all HNPCC patients?

A 34-year-old male with hereditary non-polyposis colon cancer with a mutation in hMSH2 line is reported. Despite regular colonoscopic follow-up, he developed cecal cancer involving the extraluminal area. Due to sub-occlusive symptoms, the patient was submitted to further colonoscopy, however with no clear evidence of neoplasia. Thin slice multiplanar reconstruction computed tomography CT scan performed thereafter revealed a transmural mass 2.5 cm in size localized near the cecal valve. Discussion is made on the reliability of colonoscopic examinations as well as the need for further investigations in the follow-up of patients at very high risk of right-sided colon cancer, such as male hMSH2 carrier affected by hereditary non-polyposis colon cancer.

Adult↗
PubMed2004

Beta3-adrenoceptors: relaxant function and mRNA detection in smooth muscle cells isolated from the human colon.

Functional involvement of beta3-adrenoceptors in controlling human gastrointestinal motility has not been unequivocally assessed yet. The direct myogenic contribution of these receptors was examined, by in vitro functional studies and analysis of mRNA expression, on smooth muscle cells separately isolated from taenia coli and circular muscle layers of the human colon. Isoproterenol, a nonselective beta-adrenoceptor agonist, relaxed, in a concentration-dependent manner, both human taenia coli and circular colonic smooth muscle cells, although displaying a higher intrinsic activity (65.3 +/- 2.3 vs. 55.2 +/- 1.4% maximal relaxation) and potency (pEC50: 7.41 +/- 0.07 vs. 6.32 +/- 0.08) were greater on taenia coli than circular cells. In the presence of the beta1-antagonist CGP20712A and of the beta2-antagonist ICI 118,551, a 25-30% decrease in isoproterenol intrinsic activity was observed on both cell types and on taenia coli, the nonselective beta1/beta2-antagonist propranolol produced a rightward shift of the isoproterenol concentration-response curve with mean estimated pKB values (8.12 +/- 0.27 at 0.1 microM and 6.45 +/- 0.13 at 1 microM) lower than that expected for both beta1- and beta2-adrenoceptors. CGP12177A and SR 58611A, two beta3-adrenoceptor agonists, presented an intrinsic activity comparable to that of isoproterenol in the presence of beta1- and beta2-antagonists, the former being more potent on taenia coli than on circular smooth muscle cells. Beta3-adrenoceptor mRNA was detected by reverse transcription PCR on both cell types. These results strongly suggest a direct functional role of beta3-adrenoceptors in the human colon.

Adrenergic beta-Agonists↗
PubMed2003

Nonfunctioning pancreatic endocrine tumors: a multicenter clinical study.

OBJECTIVES: Nonfunctioning pancreatic endocrine tumors (NFPTs) are rare neoplasms that have been the object of few studies that have involved only small numbers of patients. This study was carried out to obtain a comprehensive and up-to-date clinical picture of these tumors. METHODS: A total of 184 patients with NFPT admitted to three Italian hospitals in the last 15 yr were studied. The diagnosis of NFPT was confirmed histologically using conventional and immunohistochemical techniques. Data were obtained from the medical charts or directly from the patients. RESULTS: There were 85 men (46.2%) and 99 women (53.8%). The mean age at diagnosis was 55.2 yr (range 17-82 yr). The percentage of smokers and alcohol drinkers was similar to that in the general population. Seven patients (3.9%) had a family history of exocrine pancreatic carcinoma. In 120 cases (65.2%), the diagnosis was made after workup for pain or other symptoms, in the remaining 64 cases (34.8%), the tumor was discovered incidentally by ultrasound; in this group survival was significantly greater than it was for the symptomatic patients (p=0.0043). Survival was also found to be improved by tumor resection (p<0.0001), absence of metastases (p<0.0001), and small tumor size (< or =3 cm) (p<0.0007). CONCLUSIONS: NFPTs were slightly more frequent in women and were diagnosed most often in middle-aged individuals. No risk factors other than a family history of exocrine pancreatic carcinoma were found. Tumor discovery while patients were still asymptomatic, tumor resection, absence of metastases, and tumor size < or =3 cm significantly prolonged survival.

Adenoma, Islet Cell↗
PubMed2002

Malignancy-associated allelic losses on the X-chromosome in foregut but not in midgut endocrine tumours.

Information on genetic changes involved in the progression of gastroenteropancreatic (GEP) endocrine tumours is scanty. On the other hand, the identification of molecular markers of malignancy could be crucial for the prognostic evaluation of these neoplasms, which is hardly predictable on the basis of conventional histological criteria. An association of X-chromosome deletions with malignancy has already been found in gastric endocrine tumours. To investigate this further, a comparative loss of heterozygosity (LOH) analysis was performed on 17 pancreatic endocrine tumours (PETs) and 17 intestinal (ten ileal, six appendiceal, and one rectal) carcinoids from female patients. The relationship of X-chromosome LOH with the ploidy status of the neoplasms was also investigated. LOH was found in six of eight malignant PETs (60% of the informative markers), but was infrequent in the nine benign ones (4.5%). In contrast, although retention of heterozygosity was consistently observed in benign midgut tumours, LOH was infrequent in malignant carcinoids (15%). No correlation was found between LOH and the ploidy status. These results indicate an association between X-chromosome LOH and malignancy in foregut endocrine tumours. The lack of such an association in midgut carcinoids suggests that different molecular mechanisms are involved in the progression of these two categories of endocrine neoplasms, which are otherwise considered to be closely related. These findings emphasize the need for further molecular studies on GEP endocrine tumours, carefully subdivided according to their anatomical site of origin.

Adult↗
PubMed2002

Effect of chronic hypergastrinemia on human enterochromaffin-like cells: insights from patients with sporadic gastrinomas.

BACKGROUND & AIMS: The effect of chronic hypergastrinemia alone on gastric enterochromaffin-like (ECL) cells in humans is largely unknown because in the common chronic hypergastrinemic states (atrophic gastritis, chronic proton pump inhibitor use), it is not possible to separate the effect of hypergastrinemia and other factors, such as gastritis or atrophy. Studies of patients with sporadic Zollinger-Ellison syndrome (ZES) allow this separation. METHODS: In 106 patients with ZES, gastric biopsies were taken, and the qualitative ECL cell pattern/grade and the alpha-subunit of human chorionic gonadotropin (alpha-hCG) expression were determined. RESULTS: In patients with active disease, 99% had ECL hyperplasia and abnormal alpha-hCG staining. Fifty percent had advanced changes in both of these, with 7% having dysplasia and 0% having carcinoids. Advanced ECL cell and alpha-hCG changes were most affected by the level of hypergastrinemia. For ECL cell changes, even mild hypergastrinemia had an effect. Advanced ECL change was also affected by the duration of drug treatment, cure status, and presence of atrophic gastritis, but not by sex or previous vagotomy. The alpha-hCG expression independently predicted dysplasia. CONCLUSIONS: In humans, chronic hypergastrinemia alone causes advanced ECL cell change and abnormal expression of mucosal alpha-hCG. No threshold for this effect was detected, as reported by some, and in contrast to animal studies, sex and vagal tone did not play a major role. The long-term risk of developing gastric carcinoids with chronic hypergastrinemia is low in patients with sporadic gastrinomas (at least 100 times less than in patients with multiple endocrine neoplasia type 1 with ZES) for at least 15-20 years.

Adolescent↗
PubMed2002

Different patterns of 11q allelic losses in digestive endocrine tumors.

Most foregut digestive endocrine neoplasms may be associated with the multiple endocrine type 1 (MEN-1) syndrome. In contrast, midgut/hindgut carcinoids never show such association. To investigate the pathogenetic involvement of the MEN-1 gene and of putative additional oncosuppressor gene(s) distal to it, a comparative analysis of loss of heterozygosity (LOH) at chromosome 11q13 to 11qter was performed in 27 foregut (pancreatic endocrine tumors [PETs]), 23 midgut (ileal and appendiceal), and 3 hindgut (rectal) endocrine tumors. LOH at the MEN-1 gene locus at 11q13 was observed in 52% of the 23 sporadic and in all 4 MEN-1-associated PETs and was found to consistently and continuously span to the most distal marker investigated at 11qter. In contrast, only occasional, discontinuous, and mostly interstitial LOH for 11q markers was observed in ileal (midgut) carcinoids, whereas no LOH was found in all appendiceal (midgut) and rectal (hindgut) carcinoids. The consistent extension of LOH from the MEN-1 region to 11qter in sporadic PETs suggests a mechanism of gene inactivation via chromosomal breakage and complete loss of chromosome 11q; furthermore, these results expand beyond the 11q13 region the search for additional oncosuppressor gene(s) potentially involved in the genesis of these neoplasms. The low frequency, limited extension, and discontinuous distribution of 11q deletions in midgut/hindgut carcinoids suggest that MEN-1 gene is not involved in the pathogenesis of these tumors.

Adult↗