DNA repair genes polymorphisms and risk of colorectal cancer in Saudi patients.

BACKGROUND AND STUDY AIMS: Polymorphisms in the DNA repair genes may influence individual capacity to repair DNA damage, which may be associated with increased genetic instability and carcinogenesis. Our aim was to evaluate the relation of genetic polymorphisms in 2 DNA repair genes, XPD Lys751Gln and XRCC1 (A399G), with colorectal cancer (CRC) susceptibility. We further investigated the potential effect of these DNA repair variants on clinicopathological parameters of CRC patients. PATIENTS AND METHODS: Both XPD and XRCC1 polymorphisms were characterised in one hundred CRC patients and one hundred healthy controls who had no history of any malignancy by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method and PCR with confronting two-pair primers (PCR-CTPP), using DNA from peripheral blood in a case control study. RESULTS: Our results revealed that the frequencies of GG genotype of XRCC1 399 polymorphism were significantly higher in the CRC patients than in the normal individuals (p⩽0.03), and did not observe any association between the XPD Lys751Gln polymorphism and CRC risk. We found association between both XRCC1 A399G polymorphisms and histological grading of disease. CONCLUSION: Our results suggested that, XRCC1 gene is an important candidate gene for susceptibility to colorectal carcinoma.

A scoring system for the prediction of choledocholithiasis: a prospective cohort study.

BACKGROUND: Techniques for diagnosing choledocholithiasis pose significant morbidity and mortality risks. OBJECTIVES: We aimed to develop and validate a clinical scoring system for predicting choledocholithiasis. DESIGN: Data from a prospectively maintained database of all patients with gallstones. SETTING: Patients were admitted to the general surgery department of a military hospital. PATIENTS AND METHODS: We enrolled consecutive patients with symptomatic gallstones, biliary pancreatitis, obstructive jaundice, or cholangitis, who subsequently underwent biochemical testing and ultrasonography. A predictive model was developed from a scoring system using their imaging and laboratory data. Endoscopic retrograde cholangiopancreatography (ERCP) or intraoperative cholangiography were used for confirmatory diagnoses. The predictive efficacy of the scoring system was validated using a retrospective cohort of 272 patients. MAIN OUTCOME MEASURES: Predictive accuracy of the scoring system. RESULTS: We enrolled 155 patients in the development group. The common bile duct diameter, alkaline phosphatase of >=200 IU, elevated bilirubin levels, alanine transaminase of >=220 IU, and male age of >=50 years were significantly associated with choledocholithiasis and were included in the scoring system. Ninety-six patients (35%) had scores of >=8 (high risk), 86 patients (32%) had scores of 4-7 (intermediate risk), and 27 patients (10%) had scores of 1-3 (low risk). In the validation cohort, the positive predictive value for a score of >=8 was 91.7%, and the scoring system had an area under the curve of 0.896. CONCLUSION: Scores of >=8 were strongly correlated with choledocholithiasis in the developmental and validation groups, which indicates that our scoring system may be useful for predicting the need for therapeutic ERCP. However, prospective validation in a large multicenter cohort is needed to fully understand the benefits of the system. LIMITATIONS: The retrospective validation cohort might have introduced selection and observational biases. The study may have been underpowered because of the sample size of the developmental cohort. The delay between admission and the time of ERCP theoretically may have increased the number of negative ERCP results, but our false negative rate for ERCP was consistent with the previously reported rates.

Single-center experience of surgically resected gastrointestinal stromal tumors: A report of six cases, including a rare case involving the lower esophagus.

Gastrointestinal stromal tumors (GISTs) are rare, but remain the most common GI mesenchymal neoplasms. In the present study, six cases of GIST are reported, and one of these cases, a patient with esophageal GIST, is reported in-depth. Certain recent developments in the clinical therapy of GISTs are also discussed. The records of all surgically-resected GI stromal tumors treated at the Al-Hada Military Hospital between January 2007 and December 2012 were reviewed. There were six cases of surgically resected GISTs during this time period, three males and three females, with a mean age of 69.3±16.4 years. The stomach was involved in 66.7% of cases, the small intestine in 16.7% and the esophagus, which is an extremely rare site, in 16.7% of cases. The most common symptom at presentation was abdominal pain, followed by GI bleeding. The mean tumor size was 8.7±6.3 cm. Surgery was indicated by the presence of the aforementioned symptoms or a tumor size >5 cm. All tumors were completely resected with histologically negative margins. The diagnoses were established by immunohistochemistry. Four patients were classified as possessing a high-grade variant, and were administered with tyrosine kinase inhibitors (TKIs). Following a mean follow up of 31 months, no recurrence or mortality was detected. Complete surgical resection with tumor-free margins is the standard treatment for GISTs, and TKIs should be used as adjuvant therapy if the risk of progressive disease is high.

A disseminated variant of pancreatic serous cystadenoma causing obstructive jaundice, a very rare entity: a case report and review of the literature.

BACKGROUND: Microcystic adenoma or serous cystadenoma (SCA) is an uncommon tumor type, accounting for only 1-2% of pancreatic exocrine neoplasms. Usually unifocal, SCAs present as single, large, well-demarcated, multiloculated, cystic tumors, 1-25 cm in size. CASE PRESENTATION: A 73-year-old man initially presented with epigastric abdominal pain and was diagnosed with SCA involving the whole pancreas. Eleven months later, he presented with obstructive jaundice, and total pancreatectomy was performed. The removed tissue allowed histological verification of pancreatic SCA. Histopathological examination showed both microcysts and macrocysts, lined by cuboidal epithelium, with optically clear cytoplasm and the absence of detectable mitosis or necrosis. CONCLUSIONS: Thus, although relatively rare, pancreatic SCA is one of the differential diagnoses of epigastric abdominal pain; we recommend early surgical intervention for symptomatic pancreatic SCA.

Non-invasive assessment of choledocholithiasis in patients with gallstones and abnormal liver function.

AIM: To find a non-invasive strategy for detecting choledocholithiasis before cholecystectomy, with an acceptable negative rate of endoscopic retrograde cholangiopancreatography. METHODS: All patients with symptomatic gallstones were included in the study. Patients with abnormal liver functions and common bile duct abnormalities on ultrasound were referred for endoscopic retrograde cholangiopancreatography. Patients with normal ultrasound were referred to magnetic resonance cholangiopancreatography. All those who had a negative magnetic resonance or endoscopic retrograde cholangiopancreatography underwent laparoscopic cholecystectomy with intraoperative cholangiography. RESULTS: Seventy-eight point five percent of patients had laparoscopic cholecystectomy directly with no further investigations. Twenty-one point five percent had abnormal liver function tests, of which 52.8% had normal ultrasound results. This strategy avoided unnecessary magnetic resonance cholangiopancreatography in 47.2% of patients with abnormal liver function tests with a negative endoscopic retrograde cholangiopancreatography rate of 10%. It also avoided un-necessary endoscopic retrograde cholangiopancreatography in 35.2% of patients with abnormal liver function. CONCLUSION: This strategy reduces the cost of the routine use of magnetic resonance cholangiopancreatography, in the diagnosis and treatment of common bile duct stones before laparoscopic cholecystectomy.

Malignant extra-adrenal pancreatic paraganglioma: case report and literature review.

BACKGROUND: Pancreatic paragangliomas are rare tumors, with only 16 reported cases to date. One of these cases demonstrates metastasis to lymph node, while another case was functional, however, none of these cases showed malignant and large, pancreatic paraganglioma with marked invasion. Also another unique feature was the age of our patient compared to the average reported ages in published literature (42-85 years). CASE PRESENTATION: A 19-year-old woman presented with a one-year history of intermittent abdominal pain. Physical examination showed a palpable mass in the right upper abdomen, but initial laboratory results were within normal ranges; tumor markers (CEA, AFP, and CA19-9) were negative. An abdominal and pelvic computed tomography (CT) scan showed a well-defined retroperitoneal para-aortic mass. The CT scan revealed that the surrounding lymph nodes were not enlarged, but the liver showed evidence of parenchymal infiltration. Intraoperatively, a large, firm tumor originating from the head of pancreas was found pushing on the caudate hepatic lobe and the inferior vena cava (IVC). The tumor was resected through a pancreaticoduodenectomy, involving segment VI of the liver and a small segment of the IVC. The blood pressure spiked (>220 mm Hg) when the tumor was manipulated during the operation. The final pathology report showed a 9-cm tumor with lymphovascular invasions; immunohistochemistry was positive for synaptophysin and chromogranin. All resection margins were negative and 1/15 lymph nodes was positive for metastasis. Post-operative recovery was unremarkable. One month after discharge, the patient was re-admitted with abdominal pain and found to have an abdominal collection at the resection site, which was drained under CT guidance. She received a therapeutic dose of I131-metaiodobenzylguanidine (MIBG). Follow-ups showed the absence of recurrence, and she has remained disease free. CONCLUSION: This patient was an extraordinary example of a rare tumor. Even more remarkable was that the tumor was malignant with lymph node invasion. To our knowledge, a case similar to that presented here has not been previously reported in the literature.

Neuroendocrine small cell rectal cancer metastasizing to the liver: a unique treatment strategy, case report, and review of the literature.

We describe the treatment of a 46-year-old Saudi man with advanced stage liver metastatic neuroendocrine rectal cancer. The patient presented with a large liver lesion and rectal bleeding. He was cachectic, with a firm tender mass 20 mm above the anal verge. Computed tomography (CT) showed a mass 9.5 × 13 cm in size in the right hemi-liver, abutting the middle hepatic vein. The patient refused treatment, and consulted another hospital. After 3 months, he presented with the same symptoms in addition to delirium. Colonoscopy showed an ulcerating anorectal mass, from which a biopsy was taken. Repeat CT showed an increase in the size of the liver lesion to 17 cm and no change in the pelvis. The final histopathology report identified anaplastic small cell carcinoma. The patient underwent extended right liver resection followed by abdominoperineal resection, then 13 cycles of chemotherapy and monthly somatostatin injections. At the most recent follow-up, the patient had been disease-free for 48 months. Surgical resection (R0) of the primary and secondary tumor, followed by platinum-based chemotherapy can result in good survival in cases of small cell carcinoma with large liver metastasis, irrespective of whether the primary or secondary tumor is resected first.

Changes in gallbladder motility and gallstone formation following laparoscopic gastric banding for morbid obestity.

UNLABELLED: Morbid obesity is associated with cholesterol gallstone formation, a risk compounded by rapid weight loss. Laparoscopic gastric banding allows for a measured rate of weight loss, but the subsequent risk for developing gallstones is unknown. METHOD: Twenty-six normal-weight volunteers (body mass index [BMI] less than 30) were compared with 14 morbidly obese patients (BMI greater than 40). Gallbladder volumes were measured ultrasonographically, after fasting and following stimulation with intravenous cholecystokinin-octapeptide (CCK-8) RESULTS: Preoperatively, fasting gallbladder volume and residual volume after CCK stimulation were both two times greater in the obese group (P<0.02 versus controls). Per cent gallbladder emptying was not different. Gallbladder refilling was four times higher in the obese patients (P<0.01). By six weeks postoperatively, the obese patients lost 1.4+/-0.1% body weight per week. Gallbladder emptying decreased 18.4% (80.3+/-3.9% to 65.5+/-6.9%; P<0.05); residual volume rose one-third (not significant), and refilling fell 60.5% (0.43+/-0.09 to 0.26+/-0.04 mL/min; P=0.07). Three patients with weight losses of greater than 1.7% per week developed gallstones; gallbladder emptying fell outside the 95 percentile. By six months, weight loss slowed to 0.5+/-0.1% per week; gallbladder motility improved modestly. No further stones developed. CONCLUSION: Rapid weight loss following laparoscopic gastric banding impairs gallbladder emptying and when pronounced, gallstones form by six weeks postoperatively. The accompanying reduction in gallbladder emptying, increased gallbladder residual volume and decreased refilling promote gallbladder stasis and hence stone formation.

Endothelins induce gallbladder contraction independent of elevated blood pressure in vivo in the Australian possum.

Endothelin levels are elevated in shock, sepsis, and cholestatic jaundice, and an effect on biliary motility may be postulated. The aim of this study was to determine whether (1) endothelin-1 and endothelin-3 induce gallbladder contraction in vivo, (2) the response is caused by changes in blood pressure, and (3) the response is nerve mediated. Gallbladder pressure and blood pressure were measured in 38 anesthetized possums. Endothelin-1 or endothelin-3 (5 to 200 pmol/kg) was administered by close intra-arterial injection. Tetrodotoxin (9 microg/kg) or the mixed endothelin antagonist tezosentan was infused at a rate of 10 or 100 nmol/kg/min (close intra-arterial injection). Maximum changes in gallbladder pressure (% of carbachol-induced contraction) and blood pressure (mm Hg) were determined. Statistical analysis was carried out by means of repeated-measures analysis of variance and Kruskal-Wallis test. Both endothelin-1 and endothelin-3 induced dose-dependent increases in gallbladder pressure and blood pressure (P < 0.05), which were unaffected by pretreatment with tetrodotoxin. The endothelin-1-induced gallbladder pressure but not blood pressure was reduced by the higher dose of tezosentan (P < 0.03). The lower dose of tezosentan also produced a decrease in the endothelin-3-induced gallbladder pressure (P < 0.02) but not in blood pressure, whereas the higher dose reduced the blood pressure with no further reduction in gallbladder pressure (P < 0.05). Endothelins increase gallbladder motility in vivo, acting directly on the smooth muscle and independent of changes in blood pressure.

Endothelin-3 induces both human and opossum gallbladder contraction mediated mainly by endothelin-B receptor subtype in vitro.

BACKGROUND: Endothelins are produced by gallbladder epithelial cells, suggesting a role in the regulation of gallbladder function. AIMS: To characterize the effect of endothelin-3 (ET-3) on human and Australian possum gallbladder contractility and identify the receptor(s) involved. METHODS: Human and possum gallbladder muscle strips were exposed to cumulative concentrations of ET-3 (10 pmol/L-100 nmol/L). Strips were pretreated with either tetrodotoxin (TTX) (1 micro mol/L), the selective ET receptor antagonists BQ-123 (ET(A)), BQ-788 (ET(B)), alone or together, or the mixed ET antagonist tezosentan (all 1 micro mol/L). Maximal changes in tone were measured and expressed as percentage of carbachol (100 micro mol/L)-induced tone. ANOVA was used for statistical analysis. RESULTS: Endothelin-3 induced a concentration-dependent increase in tone in both human and pos-sum strips (P < 0.05) and at 100 nmol/L represented 44.2 +/- 4.5% and 40.3 +/- 4.6% of carbachol-induced tone, respectively. The effect on human strips was TTX insensitive, whereas the possum concentration-response curve was shifted to the right. Individually, BQ-123 and BQ-788 shifted the human concentration-response curve to the right, but a greater inhibition by BQ-788 was achieved in the possum (P < 0.05). However, BQ-123 plus BQ-788 further reduced the ET-3 effect (P < 0.001) to a level comparable to that observed in the presence of tezosentan in both human and possum strips. CONCLUSION: Endothelin-3 produces potent gallbladder contraction in vitro, acting mainly via ET(B) receptors and also interacting with ET(A)receptors. The receptors are located on the smooth muscle, but in possum gallbladder, neural receptors may also be involved. These findings suggest that ET-3 may regulate motility of possum and human gallbladder.