Embryonic transcription factors CDX2 and Oct4 are overexpressed in neuroendocrine tumors of the ileum: a pilot study.

BACKGROUND: Neuroendocrine tumors (NETs) of the ileum are rare submucosal tumors that are often diagnosed at advanced stages with metastatic spread to the liver causing a carcinoid syndrome. They present as solitary or multiple tumors. In NETs, loss of sequences on chromosomes 11, 16, 18 and 22 or gain of sequences on chromosomes 17 and 19 has been described. In this study we explored the expression of two novel candidate genes, CDX2 and Oct4, in NETs of the ileum and analyzed whether the molecular expression pattern correlates with the clinical phenotype (solitary/multiple tumors). METHODS: Data from all patients who underwent surgery for a NET of the ileum between 2000 and 2010 were retrieved from a prospective database. For each patient, frozen normal and tumor tissue was used for the comparison of gene expression levels of two putative cancer stem cell markers, CDX2 and Oct4, using real-time PCR (rtPCR). Serial slides from paraffin blocks were used for immunohistochemistry. Gene expression was compared between normal and tumor tissue as well as between solitary and multiple tumors. RESULTS: 78 patients were identified. In rtPCR, a statistically significant higher expression of CDX2 in tumor tissue (p < 0.001) compared to normal tissue was found. The expression of Oct4 was elevated in the tumors, but did not reach the level of significance (p = 0.155). The expression of both candidate genes was confirmed immunohistochemically and showed a nuclear expression pattern. There was no difference in expression between solitary and multiple tumors or between tumors that had already spread to the liver. CONCLUSION: CDX2 is overexpressed in ileum NETs, thus playing a role in the tumorigenesis of these rare tumors. Since expression does not correlate with clinical stage or phenotype, it might be an early event in tumor development.

Harmonic scalpel versus conventional dissection technique in pylorus-preserving partial duodenopancreatectomy.

BACKGROUND/AIMS: Pancreatic head resection is performed with low mortality, but morbidity remains high. Extensive preparation, long operating times, intraoperative blood loss and the need for blood transfusions are risk factors for postoperative morbidity. The aim of our study was to evaluate the feasibility and safety of the ultrasonic dissection device in pylorus-preserving duodenopancreatectomy (PPPD). METHODS: Fifty consecutive patients who underwent PPPD with an ultrasonic dissection device (group 1) were compared with a match-controlled group of 50 consecutive patients who underwent PPPD with conventional dissection techniques (group 2). Duration of surgery, intraoperative blood loss, blood units, complications, mortality and duration of hospital stay were analyzed. RESULTS: There was no difference in age, gender or BMI between groups. In group 1, mean blood loss (446 ± 281.8 ml, p = 0.008) and number of blood units (0.32 ± 0.86, p = 0.001) were significantly lower than in group 2 (819 ± 915.4 ml; 1.36 ± 2.83 units). Duration of surgery was shorter in group 1 (345.6 vs. 373 min, p = 0.28). The rate of postoperative complications, mortality and hospital stay were not significantly different. CONCLUSIONS: Use of an ultrasonic dissection device in PPPD might significantly reduce intraoperative blood loss and the need for blood transfusions. These results should be verified in a prospective randomized controlled trial.

Differentiation between thyroidal and ectopic calcitonin secretion in patients with coincidental thyroid nodules and pancreatic tumors - a report of two cases.

Although elevated blood levels of calcitonin are considered highly indicative for the presence of medullary thyroid carcinomas, they may be observed in patients with chronic kidney disease or in consequence of ectopic calcitonin production. We report two patients who presented with excessively elevated calcitonin levels. Diagnostic work-up revealed a single thyroid nodule and a pancreatic tumor with ectopic calcitonin secretion in both of them. On the basis of these case reports, the diagnostic work flow and management in case of clearly elevated calcitonin levels are described and discussed.