Transanal endoscopic microsurgery for rectal tumors: the St. Mary's experience

BACKGROUND: The aim of this study is to describe a single institution's experience in the use of transanal endoscopic microsurgery for rectal tumors. METHODS: Between 1996 and 2005, transanal endoscopic microsurgery was performed in 76 patients. The histologic diagnosis was adenoma in 48 and adenocarcinoma in 28 patients. RESULTS: Clear resection margins were achieved in 71 of 74 patients (95.9%). Overall morbidity was 18.9% because 14 patients developed minor (10 patients) or major complications (4 patients). During the follow-up, benign tumor recurrence was detected in 3 patients (6.3%). The recurrence rates among patients with T1, T2, and T3 malignant tumors were 7.1%, 42.8%, and 66.6%, respectively. COMMENTS: Transanal endoscopic microsurgery is a safe and feasible technique with low incomplete excision rates and may be the preferred method in patients with benign rectal tumors. Its role in the management of malignant tumors should be limited to selected patients with T1 lesions.     

The sodium-iodine symporter and the proton-pump inhibitors in - related to the side effects of- the treatment of thyroid cancer with iodine-131

Iodine-131 ((131)I) administered to patients for imaging or treatment, concentrates in the gastrointestinal tract, including the salivary glands, stomach and bowel. In Nuclear Medicine practice this biological property of iodine causes side effects when the therapeutic dose of (131)I is large. This occurs during the treatment of patients with differentiated thyroid carcinoma (DTC). During this clinical application, the dose of (131)I is higher than 3.7 GBq. Side effects of this treatment with respect to the stomach, include gastritis as an inflammatory reaction to radiation, anorexia due to gastric atrophy and rarely megaloblastic anemia due to lack of the endogenous factor. Side effects can also include xerostomia. We have recently tried to prevent gastric side effects by prescribing proton pump inhibitors (PPI) for patients with DTC prior to treatment with (131)I. PPI block the excretion of hydrochloric acid from the gastric mucosa and are utilized for the prevention and treatment of gastritis, gastric ulcers and gastroesophageal reflux. Whole body scans before or after the administration of PPI, showed that PPI do not interfere with the biologic distribution of (131)I. These findings were not surprising. Recent studies in animals and humans have shown that the accumulation and concentration of iodine by the thyroid gland is the result of the selective action of sodium iodine symporter (Na+I+symporter, NIS). Furthermore, it was shown that the accumulation and concentration of (131)I in the parietal cells of the gastric mucosa, the ductal cells of the salivary glands and the alveolar epithelial cells of the mammary glands, is analogous to the biologic action of NIS in the thyroid cells. The gastric mucosa accumulates iodine from the capillaries via the extracellular/extravascular space and finally excretes it into the lumen of the stomach, from where it is passively transferred into the bowel, where it is partially reabsorbed to once again enter its metabolic cycle. On the contrary, as it is now known, the PPI have an entirely different metabolic action, which is unrelated to that of the NIS, although both mechanisms coexist in the parietal cells of the gastric mucosa. Thus, during the application of (131)I for imaging or for the treatment of DTC patients, except for the short period of time immediately after the oral administration, when the radionuclide passes through the stomach, the concentration of (131)I in the gastrointestinal tract is due to its active accumulation and excretion by the gastric mucosa. PPI act only on the hydrochloric acid secretion not affecting the biologic properties of iodine.     

Hedgehog signalling in colorectal tumour cells: induction of apoptosis with cyclopamine treatment

Hedgehog (Hh) signalling controls many aspects of development. It also regulates cell growth and differentiation in adult tissues and is activated in a number of human malignancies. Hh and Wnt signalling frequently act together in controlling cell growth and tissue morphogenesis. Despite the fact that the majority of colorectal tumours have a constitutively activated canonical Wnt pathway, few previous studies have investigated the expression of Hh signalling components in colorectal tumours. We describe here epithelial cell lines derived from both nonmalignant colorectal adenomas and colorectal adenocarcinomas that express both Sonic and Indian Hh. Interestingly, these cells also express the Hh receptor Patched and the downstream signalling components Smoothened and Gli1, suggesting autocrine Hh signalling in these cells. To test whether autocrine Hh signalling contributes to cell survival, we treated colorectal tumour cells with cyclopamine, a known inhibitor of Hh signalling. Cyclopamine treatment induced apoptosis in both adenoma- and carcinoma-derived cell lines, which could be partially rescued by further stimulation of Hh signalling. These data suggest that autocrine Hh signalling can increase aberrant cell survival in colorectal tumour cells and may be a novel target for colon cancer therapy using drugs such as cyclopamine.     

Impact factor bias and proposed adjustments for its determination

BACKGROUND: The impact factor (IF), a qualitative parameter used to evaluate scientific journals, has several flaws. The aim of the study was to evaluate two of its important constraints, journal self-citation and scientific field, and to investigate the potential for improvement. METHODS: We studied the five or six highest impact journals from each of seven medical fields: anesthesiology, dermatology, genetics and heredity, immunology, general and internal medicine, ophthalmology and surgery. To correct for journal self-citation, we divided the number of 1998 citations of papers published in 1996 and 1997, minus the self-citations, by the number of papers published in the same period. For inter-field normalization we divided the IF by the mean of the IFs of the upper quartile for the same category of medical field (IF/fcat). RESULTS: For the 36 journals, there was a negative correlation between IF and self-cited and self-citing rates (rs = -0.765, P < 0.001 and rs = -0.479, P < 0.003, respectively). Self-cited rate is the ratio of a journal's self-citations to the number of times it is cited by all journals including itself. Self-citing rate relates a journal's self-citations to the total references it makes. The IF/fcat for the 36 journals are positively correlated with their conventional IF (rs = 0.91, P < 0.001). CONCLUSION: Correcting the IF of the 36 journals for self-citation did not significantly change journal rankings. The adjusted IF/fcat to normalize for the scientific field was positively correlated with the conventional IF.     

Surgical treatment of a giant mesenteric fibromatosis mimicking a gastrointestinal stromal tumor: a case report and current treatment aspects

Intra-abdominal fibromatosis (IAF), usually located at the mesenteric level, is a locally invasive tumor of fibrous origin. Although lacking the ability to metastasize, it has the tendency to recur. The case described here is a case of mesenteric fibromatosis with involvement of the bowel wall, which had the appearance of a gastrointestinal stromal tumor (GIST), a tumor with malignant behavior. This report outlines the fact that certain non-typical cases of IAF with involvement of the bowel wall can be misdiagnosed as GIST. It is of outmost importance to make an early and correct diagnosis in such equivocal cases, so that the appropriate treatment can be closed.     

Transdermal clonidine: does it affect pain after abdominal hysterectomy?

Clonidine has analgesic properties. We evaluated the analgesic effect of clonidine perioperatively. Forty patients undergoing abdominal hysterectomy received randomly the evening before surgery transdermal clonidine covered with overlay (CLO group) or the overlay alone (CTL group). Ten min before induction they received i.v. clonidine 1 microgram.kg-1 (CLO) or normal saline (CTL). Induction was accomplished with fentanyl 5 micrograms.kg-1, thiopentone 5 mg.kg-1, cis-atracurium 0.15 mg.kg-1 and maintenance with sevoflurane 2% in 70% N2O. Hemodynamic parameters were recorded intraoperatively. Pain was assessed by VAS at rest and movement 2, 4, 6, 8, 24, 48, 72 h and 30 days, postoperatively. During the first 8 h postoperatively all patients received controlled analgesia with fentanyl followed by morphine i.m. 0.15 mg.kg-1 and paracetamol. From 24-72 h postoperatively, patients received 75 mg propoxyphene and 600 mg paracetamol i.m., on demand. Arterial blood pressure was lower in the CLO group 0, 3, 10 min after intubation. There was no difference in pain or fentanyl consumption 8 h postoperatively. The CLO group required less analgesics 24 h postoperatively (p = 0.023). The two groups did not differ in pain or analgesic requirements 72 h and 30 days postoperatively. Clonidine had a weak opioid sparing effect 24 h post-operatively, but did not affect pain in long term.     

Migration and HIV epidemic in Greece

BACKGROUND: Over the last decade, Greece has experienced a massive influx of migrants from countries in South Eastern/Central Europe, the Middle East, Asia and Africa. This study aimed to estimate the percentage and the specific characteristics of HIV-positive migrants reported in Greece, and to describe the secular trend of migrants' proportion among HIV-infected individuals. METHODS: Secondary analysis of data reported to the Hellenic Centre for Infectious Diseases Control (HCIDC) during the years 1989-2003. RESULTS: From 1989 to 2003, 6292 HIV-positive cases were reported to HCIDC. Data show that 749 people (439 males, 303 females) originated from countries other than Greece. Most HIV-positive migrants come from Sub-Saharan Africa (32.44%) and nearly 20% from Central and Eastern Europe. In the Greek population, men who have sex with men (MSM) constitute 50.47% of cases, while 16.15% are heterosexuals. The epidemic profile follows a different pattern among migrants (P<0.05). Heterosexual transmission accounts for 41.52% of HIV-positive reported migrants, while 19.09% are MSM. An 11% increase for each subsequent year in the rate of HIV-positive migrants reported in Greece has been estimated using a Poisson regression model fitted to the data (IR 1.11; 95% confidence interval 1.08-1.13). CONCLUSIONS: The results suggest an increasing trend of HIV-seropositive migrants in Greece during recent years. Group-based interventions, better access to health care and a comprehensive public approach should be applied to migrants.