MicroRNA signatures in chemotherapy resistant esophageal cancer cell lines

AIM

To investigate expression of microRNA (miRNA) and potential targets in chemotherapy resistant esophageal cancer cell lines.

METHODS

An in-vitro model of acquired chemotherapy resistance in esophageal adeno- (EAC) and squamous cell carcinoma (ESCC) cells was used, and microRNA expression profiles for cisplatin or 5-fluorouracil (5-FU) resistant variants vs chemotherapy sensitive controls were compared using microarray and quantitative real-time polymerase chain reaction (PCR). The expression of chemotherapy-relevant genes potentially targeted by the dysregulated microRNAs in the chemotherapy resistant variants was also evaluated.

RESULTS

Chemotherapy resistant sublines were found to have specific miRNA signatures, and these miRNA signatures were different for the cisplatin vs 5-FU resistant cells from the same tumor cell line, and also for EAC vs ESCC cells with resistance to the same specific chemotherapy agent. Amongst others, miR-27b-3p, miR-193b-3p, miR-192-5p, miR-378 a-3p, miR-125a-5p and miR-18a-3p were dysregulated, consistent with negative posttranscriptional control of KRAS, TYMS, ABCC3, CBL-B and ERBB2 expression via these miRNAs.

CONCLUSION

The current study supports the hypothesis that microRNA expression has an impact on chemotherapy resistance in esophageal cancer.

Expandable metallic stents should not be used in the treatment of benign esophageal strictures

Expandable metallic stents have become popular in recent years for the treatment of esophageal strictures. While they are undoubtedly of great value in the palliation of malignant strictures and tracheo-esophageal fistulas, there is concern over their use for the treatment of benign diseases. We report three cases, in which such problems were seen following stent insertion for benign esophageal strictures. All three patients developed further strictures above the stents, one was complicated by a tracheo-esophageal fistula and two stents (in one patient) migrated distally into the stomach. Two of the patients underwent subsequent esophageal surgery. In both cases, this proved extremely difficult and hazardous because of the intense fibrotic reaction induced by the stents. Expandable mesh stents should not be used for the treatment of benign esophageal strictures without careful consideration of the potential problems, which can include rendering the problem inoperable.

Laparoscopic reoperation following failed antireflux surgery

BACKGROUND

The aim was to determine the feasibility of laparoscopic revision surgery following previous open and laparoscopic antireflux operations.

METHODS

The outcome was determined for 27 patients (14 men, 13 women) who had undergone attempted laparoscopic revision between 3 months and 25 years after a previous antireflux operation. Median follow-up was 12 (range 3-48) months.

RESULTS

Thirteen patients had previously had an open antireflux procedure (Nissen fundoplication, seven; transthoracic anatomical repair, five; Belsey procedure, one) and 14 a laparoscopic procedure (Nissen, 12; anterior partial fundoplication, two). The indications for revision were: recurrent reflux, 15; paraoesophageal hiatus hernia, six; troublesome dysphagia, six. Fifteen procedures comprised construction of a new Nissen fundoplication, six conversion from a Nissen to a partial wrap, three repair of a paraoesophageal hernia and three widening of the oesophageal hiatus. Revision was successfully completed laparoscopically in 12 patients following a previous laparoscopic procedure and in nine following a previous open operation. Median operating time was 105 min after previous open surgery and 80 min after laparoscopic surgery. No perioperative complications occurred in either group and a good outcome was achieved in 25 of the 27 patients.

CONCLUSION

Laparoscopic reoperative antireflux surgery is feasible. Reoperation is likely to be more difficult following failure of an open procedure than a laparoscopic one.

Importance of dissection of the hernial sac in laparoscopic surgery for large hiatal hernias

HYPOTHESIS

Laparoscopic repair of large hiatal hernia is an appropriate management strategy.

DESIGN

A prospective patient series.

SETTING

A university teaching hospital.

PATIENTS

All patients with hiatal hernias 10 cm or greater in diameter repaired laparoscopically between February 1, 1992, and September 30, 1998.

INTERVENTIONS

Two operative strategies were used for laparoscopic repair: the first, which was used until early 1996, entailed initial esophageal dissection while leaving the sac in the mediastinum. The second involved preliminary dissection of the hernial sac from the mediastinum before dissecting the esophagus.

MAIN OUTCOME MEASURES

Successful completion of the procedure using a laparoscopic technique, postoperative complication rate, reoperation rate, and clinical outcome.

RESULTS

Eighty-six patients with a large hiatal hernia underwent attempted repair using laparoscopic methods. The median age was 63 years (range, 30-91 years), and 45 patients (52%) were women. There were 30 sliding, 10 rolling, and 46 mixed hiatal hernias. Operating times ranged from 48 to 240 minutes (median, 90 minutes), and 20 procedures (23%) were converted to an open operation. Conversion was significantly more common in the first half of our experience (16 [40%] of 40 patients vs 4 [9%] of 46 patients) before the operative strategy was changed. Esophageal-lengthening procedures were not carried out for any patient. At follow-up of a median of 2 years, 1 patient has moderate dysphagia, 4 patients have reflux symptoms, and 1 patient has undergone further surgery for a recurrent paraesophageal hernia. An overall satisfactory outcome was achieved in 81 patients (94%).

CONCLUSIONS

Large hiatal hernias can be treated effectively laparoscopically. Dissecting the sac fully from the mediastinum before dissecting the esophagus helps to safely mobilize the esophagus, and we think changing to this strategy is the main reason for the improved laparoscopic success rate reported in the latter half of this series.

Wound metastasis after laparoscopy with different insufflation gases

BACKGROUND

There is growing evidence that laparoscopy for malignancy is associated with an increased incidence of metastasis to port sites. This study investigated the effect of different insufflation gases on port-site metastasis after laparoscopy in an established animal model.

METHODS

Forty-eight Dark Agouti rats with an established adenocarcinoma in the left flank underwent laparoscopic intraperitoneal tumor laceration. The gas used for insufflation was one of the following (12 rats in each group): (1) CO2, (2) N2O, (3) helium, or (4) air. Rats were killed 7 days after the procedure, and the port sites were examined for the presence of tumor metastasis.

RESULTS

Tumor involvement of port sites was significantly less likely after helium insufflation than in the other groups (p < 0.0001). There was no significant difference between the air, CO2, and N2O groups.

CONCLUSIONS

This study suggests that the development of metastases in port sites after laparoscopy may be influenced in part by the choice of insufflation gas used to create the pneumoperitoneum. In particular, helium was associated with a reduced rate of metastases.

Outcome of laparoscopic Nissen fundoplication in patients with disordered preoperative peristalsis

BACKGROUND

A 360 degrees or Nissen fundoplication remains controversial in patients with disordered peristalsis, some surgeons preferring a partial wrap to minimise postoperative dysphagia.

AIM

To evaluate symptoms and manometric outcome in patients with disordered peristalsis after Nissen fundoplication.

PATIENTS

In an initial series of 345 patients studied prospectively, 31 patients who had undergone a Nissen fundoplication had disordered peristalsis. Using preoperative manometry, patients were classified as: equivocal primary peristalsis (eight patients); abnormal primary peristalsis (four patients); abnormal maximal contraction pressure (13 patients); abnormal primary peristalsis and maximal contraction pressure (six patients).

METHODS

Postoperatively, patients underwent a barium meal, oesophageal manometry and standardised clinical review by a blinded scientific officer.

RESULTS

Twenty eight (90%) patients had satisfaction scores of at least 8 out of a maximum of 10 and all would undergo surgery again. Whereas 15 (48%) patients had dysphagia scores greater than 4/10 preoperatively, only two (6%) had these scores at one year. Improved peristalsis was seen in 78% of postoperative manometric studies, and mean preoperative lower oesophageal sphincter pressure increased from 6.6 (range 0-21) mm Hg to 19 (4-50) mm Hg.

CONCLUSIONS

These results are similar to the overall group of 345 patients and suggest that disordered peristalsis, and possibly even absent peristalsis, is not a contraindication to Nissen fundoplication as performed in these patients.

Laparoscopic antireflux surgery in the treatment of gastroesophageal reflux in patients with Barrett esophagus

BACKGROUND

Patients with gastroesophageal reflux and Barrett esophagus may represent a group of patients with poorer postoperative outcomes. It has been suggested that such patients should undergo open rather than laparoscopic antireflux surgery.

HYPOTHESIS

The laparoscopic approach to antireflux surgery is appropriate treatment for patients with Barrett esophagus who have symptomatic gastroesophageal reflux disease.

METHODS

The outcome of 757 patients undergoing laparoscopic surgery for gastroesophageal reflux disease from January 1, 1992, through December 31, 1998, was prospectively examined. Barrett esophagus was present in 81 (10.7%) of these patients (58 men and 23 women). The outcome for this group of patients was compared with that of patients undergoing surgery who did not have Barrett esophagus.

RESULTS

The types of operation performed were similar for the 2 patient groups. The mean +/- SD length of columnar mucosa was 47.4 +/- 43.6 mm. The average +/- SD operation time was 79.0 +/- 33.4 minutes. Conversion to open surgery occurred in 6 patients. Postoperative outcomes were as follows. Esophageal manometry and 24-hour pH studies before and after laparoscopic fundoplication demonstrated a significant increase in lower esophageal sphincter resting and residual relaxation pressures and a significant decrease in distal esophageal acid exposure. Four patients have developed high-grade dysplasia or invasive cancer within 4 years of their antireflux surgery, and all of these have subsequently undergone esophageal resection.

CONCLUSIONS

The outcome of laparoscopic antireflux surgery is similar for patients with Barrett esophagus compared with other patients with gastroesophageal reflux disease. This suggests that laparoscopic surgery is appropriate treatment for this patient group.

Randomized trial of division versus nondivision of the short gastric vessels during laparoscopic Nissen fundoplication: 10-year outcomes

BACKGROUND

Although laparoscopic Nissen fundoplication is an effective procedure for the treatment of gastroesophageal reflux, in some patients it is followed by troublesome side effects, such as dysphagia, abdominal bloating, and inability to belch. It has been claimed that dividing the short gastric blood vessels during laparoscopic Nissen fundoplication minimizes the risk of these problems. We have previously reported the 6-month and 5-year outcomes from a randomized trial, which have shown no advantages after division of these vessels. In this study, we determined the longer-term (10 years) outcomes from this trial.

METHODS

From May 1994 to October 1995, 102 patients with gastroesophageal reflux disease who underwent a laparoscopic Nissen fundoplication were entered into this randomized trial (vessels divided in 50, not divided in 52). At 10-year follow-up, 88 patients provided clinical follow-up information. Follow-up was obtained by telephone interview conducted by an independent and blinded investigator who applied a standardized questionnaire.

RESULTS

At 10-year follow-up no significant differences between the 2 groups could be identified. Heartburn, dysphagia, and overall satisfaction were similar for both study groups.

CONCLUSIONS

The 10-year clinical outcomes from this trial have shown no benefit for division of the short gastric vessels during laparoscopic Nissen fundoplication.

Chemotherapy-induced modification of microRNA expression in esophageal cancer

Neoadjuvant chemotherapy is often used in the treatment of advanced esophageal cancer. In this study, we determined the impact of chemotherapy on microRNA (miRNA) expression in esophageal cancer cells, and whether identified changes might have biological relevance. Two esophageal carcinoma cell lines (one adenocarcinoma and one squamous cell carcinoma) were treated with cisplatin or 5-fluorouracil for 24 or 72 h. RNA was extracted from cells following 24-h treatment, and used for microarray studies. Promising miRNA candidates were selected for RT-PCR validation. Target prediction using TargetScan, combined with bioinformatic analysis (Ingenuity Pathway Analysis, IPA), was performed to evaluate the implications of the altered miRNA expression. Thirteen miRNAs (miR-199a-5p, miR-302f, miR-320a, miR-342-3p, miR-425, miR-455-3p, miR-486-3p, miR-519c-5p, miR-548d-5p, miR-617, miR-758, miR-766, miR-1286) were deregulated after 24- and/or 72-h treatment in both cell lines, and most miRNAs presented similar expression changes after short- or long-term exposure. IPA revealed that the major networks which incorporate the predicted targets, include functions such as 'Cell death', 'Cell cycle', 'Cellular growth and proliferation', 'DNA replication, recombination, and repair' and 'Drug metabolism'. Cisplatin or 5-fluorouracil alter miRNA expression in esophageal cancer cells. IPA suggests that these miRNAs may target molecular pathways involved in cell survival after chemotherapy.

Laparoscopic cardiomyotomy and anterior partial fundoplication for achalasia

BACKGROUND

Although surgical myotomy is considered the gold standard, many different treatments have been advocated for achalasia. There are now a number of reports of cardiomyotomy being performed laparoscopically.

METHODS

This is a prospective study of 82 patients (47 male and 35 female; median age, 47 years) who underwent laparoscopic cardiomyotomy and anterior partial fundoplication for achalasia.

RESULTS

Four of the 82 procedures required conversion to open surgery, all during the early stages of the series, and two required early reoperation for a postoperative problem. The median operating time was 80 min (range, 32-210). the median hospital stay was 3 days (range, 2-18), and normal physical activity was resumed after a median of 2 weeks (range, 3 days to 12 weeks). Follow-up ranged up to 8 years (median, 2). Postoperatively, symptoms of dysphagia (to both solids and liquids), heartburn, odynophagia, chest pain, regurgitation, and cough were significantly reduced in all patients. The median overall satisfaction score (graded from 0 to 10, with 10 representing total satisfaction) was 9 (range, 0-10), and 90% of patients were highly satisfied with the surgical outcome.

CONCLUSION

Laparoscopic cardiomyotomy with anterior partial fundoplication achieves excellent symptomatic relief for patients with achalasia, and it can be performed with minimal morbidity.

Single center prospective randomized trial of laparoscopic Nissen versus anterior 90 degrees fundoplication

Although Nissen fundoplication is a very effective treatment for gastroesophageal reflux, it is associated with a small incidence of troublesome postoperative side effects. To prevent this, progressive modification of surgical techniques has led to the development of an anterior 90 degrees fundoplication. We undertook a prospective randomized trial to compare this procedure with Nissen fundoplication to determine whether it would achieve a better clinical outcome. Patients presenting to a single center for primary laparoscopic antireflux surgery were randomized to undergo either an anterior 90 degrees fundoplication (n = 40) or a Nissen fundoplication without division of the short gastric vessels (n = 39). Clinical questionnaires were used to assess outcome at 1 month, 3-6 months, and 12 months. Both patients and the clinical interviewer were masked as to which procedure was performed. Follow-up with endoscopy, esophageal manometry, and pH monitoring was also undertaken. Operating time was similar for the two procedures (60 minutes for anterior vs. 55 minutes for Nissen fundoplication). Early postoperative complications were more common after Nissen fundoplication (18% vs. 5%). Two patients underwent laparoscopic reoperation for recurrent reflux after anterior 90 degrees fundoplication, and four underwent laparoscopic reoperation after Nissen fundoplication (dysphagia, 3 patients; acute hiatus hernia, 1 patient). One year after surgery, dysphagia and other wind-related side effects were less common after anterior 90 degrees fundoplication. Control of reflux symptoms and satisfaction with the overall outcome was similar for the two procedures. Anterior 90 degrees fundoplication is followed by fewer side effects than Nissen fundoplication. This advantage is offset by a greater likelihood of reflux recurrence. However, this does not diminish patient satisfaction.

Revisional vs. primary Roux-en-Y gastric bypass--a case-matched analysis: less weight loss in revisions

With the increase in bariatric procedures performed, revisional surgery is now required more frequently. Roux-en-Y gastric bypass (RYGB) is considered to be the gold standard revision procedure. However, data comparing revisional vs. primary RYGB is scarce, and no study has compared non-resectional primary and revisional RYGB in a matched control setting. Analysis of 61 revisional RYGB that were matched one to one with 61 primary RYGB was done. Matching criteria were preoperative body mass index, age, gender, comorbidities and choice of technique (laparoscopic vs. open). After matching, the groups did not differ significantly. Previous bariatric procedures were 13 gastric bands, 36 vertical banded gastroplasties, 10 RYGB and two sleeve gastrectomies. The indication for revisional surgery was insufficient weight loss in 55 and reflux in 6. Intraoperative and surgical morbidity was not different, but medical morbidity was significantly higher in revisional procedures (9.8% vs. 0%, p = 0.031). Patients undergoing revisional RYGB lost less weight in the first two postoperative years compared with patients with primary RYGB (1 month, 14.9% vs. 29.7%, p = 0.004; 3 months, 27.4% vs. 51.9%, p = 0.002; 6 months, 39.4 vs. 70.4%, p < 0.001; 12 months, 58.5% vs. 85.9%, p < 0.001; 24 months, 60.7% vs. 90.0%, p = 0.003). Although revisional RYGB is safe and effective, excess weight loss after revisional RYGB is significantly less than following primary RYGB surgery. Weight loss plateaus after 12 months follow-up.

Effect of estrogen on growth and apoptosis in esophageal adenocarcinoma cells

The epidemiology of esophageal adenocarcinoma demonstrates a strong gender bias with a sex ratio of 8-9:1 in favor of males. A potential explanation for this is that estrogen might protect against esophageal adenocarcinoma. Estrogen has previously been shown to stimulate apoptosis in esophageal squamous cancer cells. However, the effect of estrogen on esophageal adenocarcinoma cells has not been determined. We used immunoblotting analysis to determine the expression of estrogen receptors, cell adhesion marker E-cadherin, and proliferation marker Ki-67 in cell lines derived from esophageal adenocarcinoma (OE-19, OE-33) and Barrett's esophagus (QhTRT, ChTRT, GihTRT). Estrogen and selective estrogen receptor modulator (SERM)-dependent effects on cell growth were determined by the CellTiter-96 Aqueous Proliferation Assay. Apoptosis was determined by Annexin V/Propidium Iodide cell labeling and flow cytometry. We detected that physiological and supra-physiological concentrations of 17β-estradiol and SERM decreased cell growth in esophageal adenocarcinoma cells. In Barrett's esophagus cells (QhTRT, ChTRT), decreased growth was also detected in response to estrogen/SERM. The level of estrogen receptor expression in the cell lines correlated with the level of anti-growth effects induced by the receptor agonists. Flow cytometry analysis confirmed estrogen/SERM stimulated apoptosis in esophageal adenocarcinoma cells. Estrogen/SERM treatments were associated with a decrease in the expression of Ki-67 and an increase in E-cadherin expression in esophageal adenocarcinoma cells. This study suggests that esophageal adenocarcinoma and Barrett's esophagus cells respond to treatment with selective estrogen receptor ligands, resulting in decreased cell growth and apoptosis. Further research to explore potential therapeutic applications is warranted.

Transoral incisionless fundoplication 2.0 procedure using EsophyX™ for gastroesophageal reflux disease

BACKGROUND

Transoral incisionless fundoplication (TIF) using the EsophyX™ system has been introduced as a possible alternative for the treatment of gastroesophageal reflux disease (GERD). The efficacy of this procedure in our centers was evaluated.

METHODS

Patients were selected for treatment if they had typical GERD symptoms, failed management with proton pump inhibitors (PPIs), a positive esophageal pH test with symptom correlation, and no hiatus hernia larger than 2 cm.

RESULTS

Nineteen patients (11 men, 8 women) underwent the TIF procedure between April 2008 and July 2009. Mean age was 48.2 years and body mass index was 24.6. The major complication rate was 3/19, including esophageal perforation, hemorrhage requiring transfusion, and permanent numbness of tongue. At mean 10.8 months follow-up, 5/19 had completely discontinued PPIs, and 3/19 had decreased their PPI dose. However, 10/19 had been converted to laparoscopic fundoplication for recurrent reflux symptoms and an endoscopically confirmed failed valve. Nine of 17 were dissatisfied with the outcome, and eight were satisfied. Thirteen of 19 (68%) were considered to have been unsuccessful.

CONCLUSION

At short-term follow-up, the TIF procedure is associated with an excessive early symptomatic failure rate, and a high surgical re-intervention rate. This procedure should not be performed outside of a clinical trial.

Laparoscopic surgery for gastro-oesophageal reflux: beyond the learning curve

From September 1991 to October 1995, 320 Nissen fundoplications were undertaken laparoscopically by 12 surgeons at a single institution. To assess the performance of the procedure in the hands of five 'experienced' surgeons, the first 20 procedures performed by each surgeon or surgical trainee were excluded, providing a group of 174 patients for review. A short loose 360 degrees fundoplication was performed in all instances, with short gastric vessel division performed in 35.0 per cent of patients and hiatal repair in 66.7 per cent. Median operating time was 80 (range 30-210) min and median postoperative stay was 3 (range 1-19) days. Sixteen procedures (9.2 per cent) could not be completed laparoscopically and required conversion to open surgery. Some 144 patients were reviewed by a scientific officer 3 months after surgery, 85 at 12 months, and 32 at 2 years, using a standard clinical questionnaire. All but one were free from reflux symptoms, although 20.1 per cent reported some dysphagia at 3 months' follow-up; this figure declined to 11 per cent at 12 months and 6 per cent (two of 34 patients) at 2 years. At each follow-up interval, 91 per cent of patients were satisfied with the outcome of the surgery. Objective testing with oesophageal motility (75 patients) and barium swallow (113) studies 3-6 months after surgery confirmed the clinical outcome. Complications occurred in nine patients (5.2 per cent); four (2.3 per cent) of these required a subsequent operation within 30 days of surgery for bleeding (one patient), paraoesophageal herniation (one) and dysphagia (two). A further procedure was necessary in six other patients (3.4 per cent) for late problems, including paraoesophageal herniation (two), hiatal stenosis (three) and gastric obstruction (one). Revision was performed laparoscopically in two patients. The clinical results of laparoscopic Nissen fundoplication by 'experienced' laparoscopic surgeons were comparable with those of open surgery.

Prospective randomized controlled trial of argon plasma coagulation ablation vs. endoscopic surveillance of patients with Barrett's esophagus after antireflux surgery

BACKGROUND

Argon plasma coagulation is one of several techniques used to ablate Barrett's esophagus. This study assessed the efficacy and safety of argon plasma coagulation in the ablation of Barrett's esophagus in patients who have undergone antireflux surgery.

METHODS

A total of 40 patients with Barrett's esophagus who had undergone a fundoplication were entered into a prospective, randomized, unblinded study comparing argon plasma coagulation with endoscopic surveillance. Treatment was repeated until either no Barrett's epithelium remained or a maximum of 6 treatment sessions.

RESULTS

One month after the final treatment, complete ablation was achieved in 12 patients. In the remaining 8, a reduction of over 95% was observed. One patient died at 9 months of an unrelated cause. At 1 year, one patient with residual Barrett's epithelium regressed completely, while relapse of Barrett's esophagus was seen in another because of fundoplication failure. Buried glands were observed in 35% patients at 1 month, but only 5% at 1 year. Dysplasia was never seen. In the surveillance group, partial regression was observed in 11 patients, and, in 3 with short-segment Barrett's esophagus, regression was complete. The length of Barrett's esophagus increased in two patients. Two had low-grade dysplasia initially, but this was not evident at 1 year. Overall, complete ablation was achieved in 12 of 19 (63%) patients in the ablation group and 3 of 20 (15%) in the surveillance group (p<0.01).

CONCLUSIONS

Argon plasma coagulation of Barrett's esophagus is safe and effective. The effects are durable, and buried glands may resolve with time. Long-term follow-up is required to assess the impact of argon plasma coagulation on cancer risk.

Association of 3 Different Antihypertensive Medications With Hip and Pelvic Fracture Risk in Older Adults: Secondary Analysis of a Randomized Clinical Trial

IMPORTANCE

On the basis of observational studies, the use of thiazide diuretics for the treatment of hypertension is associated with reduced fracture risk compared with nonuse. Data from randomized clinical trials are lacking.

OBJECTIVE

To examine whether the use of thiazide diuretics for the treatment of hypertension is associated with reduced fracture risk compared with nonuse.

DESIGN, SETTING, AND PARTICIPANTS

Using Veterans Affairs and Medicare claims data, this study examined hip and pelvic fracture hospitalizations in Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial participants randomized to first-step therapy with a thiazide-type diuretic (chlorthalidone), a calcium channel blocker (amlodipine besylate), or an angiotensin-converting enzyme inhibitor (lisinopril). Recruitment was from February 1994 to January 1998; in-trial follow-up ended in March 2002. The mean follow-up was 4.9 years. Posttrial follow-up was conducted through the end of 2006, using passive surveillance via national databases. For this secondary analysis, which used an intention-to-treat approach, data were analyzed from February 1, 1994, through December 31, 2006.

MAIN OUTCOMES AND MEASURES

Hip and pelvic fracture hospitalizations.

RESULTS

A total of 22 180 participants (mean [SD] age, 70.4 [6.7] years; 43.0% female; and 49.9% white non-Hispanic, 31.2% African American, and 19.1% other ethnic groups) were followed for up to 8 years (mean [SD], 4.9 [1.5] years) during masked therapy. After trial completion, 16 622 participants for whom claims data were available were followed for up to 5 additional years (mean [SD] total follow-up, 7.8 [3.1] years). During the trial, 338 fractures occurred. Participants randomized to receive chlorthalidone vs amlodipine or lisinopril had a lower risk of fracture on adjusted analyses (hazards ratio [HR], 0.79; 95% CI, 0.63-0.98; P = .04). Risk of fracture was significantly lower in participants randomized to receive chlorthalidone vs lisinopril (HR, 0.75; 95% CI, 0.58-0.98; P = .04) but not significantly different compared with those randomized to receive amlodipine (HR, 0.82; 95% CI, 0.63-1.08; P = .17). During the entire trial and posttrial period of follow-up, the cumulative incidence of fractures was nonsignificantly lower in participants randomized to receive chlorthalidone vs lisinopril or amlodipine (HR, 0.87; 95% CI, 0.74-1.03; P = .10) and vs each medication separately. In sensitivity analyses, when 1 year after randomization was used as the baseline (to allow for the effects of medications on bone to take effect), similar results were obtained for in-trial and in-trial plus posttrial follow-up.

CONCLUSIONS AND RELEVANCE

These findings from a large randomized clinical trial provide evidence of a beneficial effect of thiazide-type diuretic therapy in reducing hip and pelvic fracture risk compared with treatment with other antihypertensive medications.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00000542.

The influence of prediagnostic demographic and lifestyle factors on esophageal squamous cell carcinoma survival

Demographic and lifestyle factors, in particular tobacco smoking and alcohol, are well established causes of esophageal squamous cell carcinoma (ESCC); however, little is known about the effect of these factors on survival. We included all 301 patients with incident ESCC, recruited into a population-based case-control study of esophageal cancer in Australia. Detailed information about demographic and lifestyle factors was obtained at diagnosis, and deaths were identified using the National Death Index. Median follow-up for all-cause mortality was 6.4 years. Hazard ratios (HRs) and 95% confidence intervals (95% CI) were calculated from Cox proportional hazards models, adjusted for age, sex, pretreatment AJCC tumor stage, treatment and presence of comorbidities. Two hundred and thirteen patients (71%) died during follow-up. High lifetime alcohol consumption was independently associated with poor survival. Relative to life-long nondrinkers and those consuming<1 drink/week, the HRs for those with average consumption of 7-20 drinks/week or ≥21 drinks/week were 2.21 (95% CI=1.27-3.84) and 2.08 (95% CI=1.18-3.69), respectively. There was a suggestion of worse survival among current smokers (HR=1.42, 95% CI=0.89-2.28); however, the risk of early death was greatest among current smokers who reported regularly (≥7 drinks/week) consuming alcohol (HR=3.84, 95% CI=2.02-7.32). Other lifestyle factors putatively associated with risk of developing ESCC were not associated with survival. In addition to increasing disease risk, heavy alcohol consumption may be independently associated with worse survival among patients with ESCC. Future clinical follow-up studies should consider alcohol as a potential prognosticator, in addition to known clinicopathologic factors.

Laparoscopic cardiomyotomy for achalasia: clinical outcomes beyond 5 years

BACKGROUND

Laparoscopic cardiomyotomy is the most common surgical procedure for the treatment of achalasia, although few reports describe long-term surgical outcomes.

METHODS

The outcomes for 155 patients who underwent a laparoscopic cardiomyotomy with anterior partial fundoplication more than 5 years ago (July 1992 to May 2004) were determined. Patients were followed prospectively at yearly time points using a structured questionnaire which evaluated symptoms of dysphagia, reflux, side-effects, and overall satisfaction with the clinical outcome.

RESULTS

Clinical data were available for 125 patients. Thirteen patients died within 5 years of surgery, four were unable to complete the questionnaire, and one developed esophageal squamous cell carcinoma. Nine patients were lost to follow-up, and three would not answer the questionnaire (92.2% late follow-up). Postoperative dysphagia, odynophagia, chest pain, and heartburn was significantly improved at 1 year, 5 years, and late (5+ years) follow-up, with outcomes stable beyond 12 months. Seventy-seven percent of patients reported a good or excellent result (minimal or no symptoms) at 5 years and 73% at late follow-up. At late follow-up, 90% considered they had made the correct decision to undergo surgery.

CONCLUSIONS

At minimum 5 years follow-up, laparoscopic cardiomyotomy for achalasia achieves effective and durable relief of symptoms, and most patients are satisfied with the outcome.

Stenosis of the esophageal hiatus following laparoscopic fundoplication

Three patients from an overall experience of more than 250 laparoscopic Nissen fundoplications have undergone further surgery for stenosis of the esophageal hiatus. This complication may be associated with diathermy dissection of the esophagus during laparoscopic mobilization.

Metabolic and immunologic consequences of laparoscopy with helium or carbon dioxide insufflation: a randomized clinical study

BACKGROUND

Previous studies using animal models have demonstrated that carbon dioxide (CO2) pneumoperitoneum during laparoscopy is associated with adverse physiological, metabolic, immunological and oncological effects, and many of these problems can be avoided by the use of helium insufflation. The present study was performed in patients to compare the effect of helium and CO2 insufflation on intraperitoneal markers of immunological and metabolic function.

METHODS

Eighteen patients undergoing elective upper gastrointestinal laparoscopic surgery were randomized to have insufflation achieved by using either helium (n = 8) or CO2 (n = 10) gas. Intraperitoneal pH was monitored continuously during surgery, and peritoneal macrophage function was determined by harvesting peritoneal macrophages at 5 min and 30 min after commencing laparoscopy, and then assessing their ability to produce tumour necrosis factor-alpha (TNF-alpha), and their phagocytic function.

RESULTS

Carbon dioxide laparoscopy was associated with a lower intraperitoneal pH at the commencement of laparoscopy, although this difference disappeared as surgery progressed. The production of TNF-alpha was better preserved by CO2 laparoscopy, but the insufflation gas used did not affect macrophage phagocytosis. Patients undergoing helium laparoscopy required less postoperative analgesia.

CONCLUSION

The choice of insufflation gas can affect intraperitoneal macrophage function in the clinical setting, and possibly acid-base balance. The present study suggested no immunological advantages for the clinical use of helium as an insufflation gas. The outcomes of the present study, however, are different to those obtained from previous laboratory studies and further research is needed to confirm this outcome.

Experimental study of the effect of intraperitoneal heparin on tumour implantation following laparoscopy

BACKGROUND

Conclusions drawn from clinical reports of port site metastases following laparoscopic resection of intra-abdominal malignancy are now supported by a burgeoning experimental literature which suggests that laparoscopy promotes tumour metastasis to wounds. This study investigated the effect of intraperitoneal blood and heparin on the incidence of tumour cell implantation and port site metastasis.

METHODS

Twenty-four Dark Agouti rats underwent laparoscopy with carbon dioxide insufflation and the instillation of a tumour cell suspension and/or blood into the peritoneal cavity. Rats were allocated randomly to one of the following study groups (six rats per group): (1) controls; (2) intraperitoneal blood (2 ml blood introduced from a syngeneic donor rat); (3) intraperitoneal heparin; (4) intraperitoneal blood and heparin. Rats were killed 7 days after the procedure, and the peritoneal cavity and port sites were examined for the presence of tumour.

RESULTS

Tumour implantation and port site metastases were reduced by the intraperitoneal administration of heparin, but increased by the presence of intraperitoneal blood.

CONCLUSION

The results of this study suggest that tumour implantation following laparoscopy is promoted by the presence of intraperitoneal blood and that this effect may be reduced by the use of intraperitoneal heparin.

A prospective randomized trial of laparoscopic Nissen fundoplication with anterior vs posterior hiatal repair

HYPOTHESIS

The technique used for repair of the esophageal hiatus during laparoscopic Nissen fundoplication can influence the likelihood of postoperative dysphagia.

DESIGN

A prospective double-blind randomized control trial.

SETTING

A university teaching hospital.

PARTICIPANTS

A total of 102 patients with proven gastroesophageal reflux disease, undergoing a laparoscopic Nissen fundoplication were randomized to undergo fundoplication with either anterior (47 patients) or posterior (55 patients) repair of the diaphragmatic hiatus. Patients were excluded for the following reasons: they had esophageal motility disorders, required a concurrent abdominal procedure, had undergone previous antireflux surgery, or had very large hiatus hernias.

INTERVENTIONS

Laparoscopic Nissen fundoplication with anterior vs posterior hiatal repair.

MAIN OUTCOME MEASURES

Independent assessment of dysphagia, heartburn, patient satisfaction, and other symptoms 1, 3, and 6 months following surgery, using multiple standardized clinical grading systems. Objective measurement of lower esophageal sphincter pressure, esophageal emptying time, distal esophageal acid exposure, and endoscopic assessment of postoperative anatomy and esophageal mucosa.

RESULTS

Symptoms of postoperative dysphagia, relief of heartburn, and overall satisfaction 6 months after surgery were not influenced by the hiatal repair technique. However, to achieve a similar incidence of dysphagia, more patients who initially underwent posterior hiatal repair required a second surgical procedure (6 vs 0 patients). The hiatal repair technique did not affect the likelihood of early postoperative paraesophageal herniation.

CONCLUSION

Anterior suturing of the hiatus appears to be at least as good in the short-term as posterior suturing as a method of narrowing the hiatus during laparoscopic Nissen fundoplication.

Five-year follow-up of a multicenter, double-blind randomized clinical trial of laparoscopic Nissen vs anterior 90 degrees partial fundoplication

HYPOTHESIS

Laparoscopic 90 degrees anterior partial fundoplication for gastroesophageal reflux disease achieves equivalent results to laparoscopic Nissen fundoplication.

DESIGN

A multicenter, prospective, double-blind randomized clinical trial with a minimum of 5 years' follow-up.

SETTING

Nine university teaching hospitals in 6 major cities throughout Australia and New Zealand.

PARTICIPANTS

One hundred twelve patients undergoing primary antireflux surgery were randomized to undergo either laparoscopic Nissen fundoplication (52 patients) or anterior 90 degrees partial fundoplication (60 patients).

INTERVENTIONS

Laparoscopic Nissen fundoplication with division of the short gastric vessels or laparoscopic anterior 90 degrees partial fundoplication.

MAIN OUTCOME MEASURES

Blinded assessment at 1 and 5 years' follow-up of clinical outcome for postoperative heartburn, dysphagia, gas-related symptoms, and satisfaction with the surgical outcome. Analog scales ranging from 0 to 10 were used to assess symptom severity.

RESULTS

Ninety-seven patients underwent follow-up at 5 years. Three others died during follow-up, 4 refused follow-up, and 8 were lost to follow-up; 89% remained at 5-years' follow-up. At 5 years' follow-up, mean analog scores for heartburn were 2.2 for anterior fundoplication vs 0.9 for Nissen fundoplication (P=.003). There were no significant differences between the groups for dysphagia scores. The mean score for outcome satisfaction was 7.1 after anterior fundoplication vs 8.1 after Nissen fundoplication (P=.18). Eighty-eight percent reported a good or excellent outcome following Nissen fundoplication vs 77% following anterior fundoplication.

CONCLUSIONS

Laparoscopic Nissen and anterior 90 degrees partial fundoplication achieve similar levels of patient satisfaction at 5 years' follow-up, with similar adverse effect profiles. However, at 5 years' follow-up, laparoscopic Nissen fundoplication achieves superior control of reflux symptoms.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Register Identifier: ACTRN12607000298415.

Use of antireflux medication after antireflux surgery

INTRODUCTION

It is claimed that a substantial number of patients who undergo antireflux surgery use antireflux medication postoperatively. This study was aimed to determine the prevalence and underlying reasons for antireflux medication usage in patients after surgery.

MATERIALS AND METHODS

A questionnaire on the usage of antireflux medication was sent to 1,008 patients identified from a prospective database of patients who had undergone a laparoscopic antireflux procedure.

RESULTS

A total of 844 patients (84%) returned the questionnaire. Mean follow-up was 5.9 years after surgery. A single or combination of medications was being taken by 312 patients (37%): 82% proton pump inhibitors, 9% H2-blockers and 34% antacids. Fifty-two patients (17%) had never stopped taking medication, whereas 260 patients (83%) restarted medication at a mean of 2.5 years after surgery. Return of the same (31%) or different (49%) symptoms were the commonest reasons for taking medication, whereas 20% were asymptomatic or had other reasons for medication use. Postoperative 24-hour pH studies were abnormal in 16/61 patients (26%) on medication and in 5/78 patients (6%) not taking medication.

CONCLUSIONS

Antireflux medication is frequently taken by many patients for various symptoms after antireflux surgery. Symptomatic patients should be properly investigated before antireflux medications are prescribed.