5-Hydroxytryptamine (5-HT, serotonin) is a neurotransmitter in both the central nervous system and peripheral structures, acting also as a hormone in platelets. Although its concentration in the gut covers >90% of all organism resources, serotonin is mainly known as a neurotransmitter that takes part in the pathology of mental diseases. Serotonin modulates not only CNS neurons, but also pain transmission and platelet aggregation. In the periphery, 5-HT influences muscle motility in the gut, bronchi, uterus, and vessels directly and through neurons. Serotonin synthesis starts from hydroxylation of orally delivered tryptophan, followed by decarboxylation. Serotonin acts via numerous types of receptors and clinically plays a role in several neural, mental, and other chronic disorders, such as migraine, carcinoid syndrome, and some dysfunctions of the alimentary system. 5-HT acts as a paracrine hormone and growth factor. 5-HT receptors in both the brain and gut are targets for drugs modifying serotonin neurotransmission. The aim of the present article is to review the 5-HT receptors in the gastrointestinal (GI) tract to determine the role of serotonin in GI physiology and pathology, including known GI diseases and the role of serotonin in GI pharmacotherapy.

Small bowel tumours are rare and comprise less than 2 % of all primary gastrointestinal neoplasms. Among these tumours, a leiomyosarcoma belonging to soft tissue sarcomas is extremely rare and accounts for about 1 % of malignant mesenchymal lesions in the gastrointestinal tract. Due to its aggressive nature and slow growth, it is often diagnosed at the late stage when curative treatment is impossible. Authors report a first case of leiomyosarcoma with chronic recurrent ileocaecal intussusception and literature review to analyse diagnosis and treatment features of the ileum mesenchymal tumours. We present a case of an 87-year-old Caucasian man suffering from cramp-like abdominal pain for months. Due to lack of clinical signs and unspecific complaints, a diagnosis was delayed. Despite a detailed in-hospital examination, a proper diagnosis was established as late as during an operation. The patient was treated by surgery with good results. An uncommon laparoscopic resection of the small bowel with a tumour was performed. A histopathological investigation confirmed a very rare mesenchymal lesion of the distal ileum. The patient is under control with no recurrence for 1 year of the follow-up period. Reported case indicates that a usually asymptomatic tumour can cause uncommon chronic recurrent ileus signs. CT and MRI scans are investigation of choice in such cases, but they are sometimes inconclusive. It might be worth highlighting the good results of laparoscopic leiomyosarcoma lesion resection with a very good outcome.

Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophins group which plays a crucial role in brain development and neurogenesis. In the hypothalamus it is described as playing a role in energy metabolism and feeding behaviour. The hippocampal concentration of BDNF is believed to...

Background: Brain derived neurotrophic factor (BDNF) is a neurotrophin involved in neural and metabolic diseases, but it is also one of the crucial factors in cancer development and metastases. In the current study, we investigated serum BDNF concentrations in patients that underwent surgical treatment for colorectal cancer or pancreatic cancer. Methods: Serum BDNF concentrations were measured with standard enzyme-linked immunosorbent assays, before and on the third day after the operation, in 50 consecutive patients with colorectal cancer and 25 patients with pancreatic cancer (tumours in the head of pancreas). We compared pre- and postoperative BDNF levels, according to the subsequent TNM stage, histologic stage, lymph node involvement, neuro- or angio-invasion, and resection range. Results: In the pancreatic cancer group, BDNF concentrations fell significantly postoperatively (p = 0.011). In patients that underwent resections, BDNF concentrations fell (p = 0.0098), but not in patients that did not undergo resections (i.e., laparotomy alone). There were significant pre- and postoperative differences in BDNF levels among patients with (p = 0.021) and without (p = 0.034) distant metastases. Significant reductions in BDNF were observed postoperatively in patients with small tumours (i.e., below the median size; p = 0.023), in patients with negative angio- or lymphatic invasion (p = 0.028, p = 0.011, respectively), and in patients with lymph node ratios above 0.17 (p = 0.043). In the colon cancer group, the serum BDNF concentrations significantly fell postoperatively in the entire group (p = 0.0076) and in subgroups of patients with or without resections (p = 0.034, p = 0.0179, respectively). Significant before-after differences were found in subgroups with angioinvasions (p = 0.050) and in those without neuroinvasions (p = 0.049). Considering the TNM stages, the postoperative BDNF concentration fell in groups with (p = 0.0218) and without (p = 0.034) distant metastases and in patients with tumours below the median size (p = 0.018). Conclusion: Our results suggested that BDNF might play an important role in gastrointestinal cancer development. BDNF levels were correlated with tumour volume, and with neuro-, angio- and lymphatic invasions. In pancreatic cancer, BDNF concentrations varied according to the surgical procedure and they fell significantly after tumour resections. Thus, BDNF may serve as a potential marker of complete resections in underdiagnosed patients. However, this hypothesis requires further investigation. In contrast, no differences according to the procedure was made in patients with colon cancer.

PURPOSE: The aim of the study was to determine the significance of carcinoembryonic antigen and matrix metalloproteinase 2 peritoneal washes and serum concentration in patients suffering from colorectal cancer concerning tumor staging and 5-year survival rate in these patients. METHODS: 80 patients who underwent curative surgery for colorectal cancer were included in the study. Preoperative serum and intraoperative peritoneal washes CEA and MMP-2 concentrations were measured. RESULTS: Regarding tumor penetration, CEA-s and CEA-p concentrations were higher in subsequent stages from T2 to T4. Both CEA-s and CEA-p concentrations were lower in T2 compared to T3 and T4. Significant difference of CEA-s and CEA-p was noted between T2 and T4 stages. MMP-2-s concentration was higher in T3 compared to T2, the highest MMP-2-p concentration was in T4, with no statistical significance. Regarding nodular status, a significant difference of CEA-s was noted between N0 and N1. For CEA-p, significance was found between N0 and N2 as between N1 and N2. MMP-2-s concentration was the highest in N1, MMP-2-p concentration was the highest in T4, with no statistical significance. The 5-year survival rate for all patients was 63.53%. There were significant differences in CEA-s and CEA-p concentrations between patients with negative and positive 5-year survival. CONCLUSION: Intraoperative peritoneal washes concentration of CEA may potentially serve as an important factor for more precise colorectal cancer staging. CEA-p and CEA-s concentrations correlate with survival rate in patients suffering from colorectal cancer and can be useful as an additional prognostic factor. The usefulness of MMP-2 measurement still requires further studies.