FDG uptake in colonic villous adenomas

Colonic adenomas constitute 70-80% of all colorectal polyps, and their clinical significance relates primarily to their relationship with colorectal cancer. The malignant potential of the polyps detected by FDG-PET is unknown, as not all the colonic lesions identified by FDG-PET represent colorectal malignancies. The purpose of this study was to investigate the rate of FDG-PET positivity within colonic villous adenomas. A pathology database search was performed to identify all patients diagnosed with colonic villous adenoma between June 1, 1996 and December 1, 2000. Patients with a pathologic diagnosis of colonic villous adenoma and who also had a FDG-PET study up to 1 month before colonoscopy were included in this study. FDG-PET findings were compared with pathological features. Of more than 4,000 patients, six patients were diagnosed with colonic adenoma on subsequent colonoscopy following FDG-PET study. Based on the pathological findings, these 6 patients had a total of 2 villous and 9 tubulovillous adenomas. Five of the 6 patients showed foci of increased FDG uptake in the region of the colon that corresponded to the villous adenoma(s) detected on colonoscopy, which accounted for a true-positive rate of 83.3% (5/6 subjects). Focal lesions in the colon seen on FDG-PET examinations need to be investigated further, even though some of these will prove to be villous adenomas rather than colorectal carcinomas. Future studies in a larger number of patients are needed to evaluate the relationship of histopathological features of colonic polyps and detectability of these lesions by FDG-PET.     

Screening of colonic tumors by air-inflated magnetic resonance (MR) colonography

PURPOSE: To assess the accuracy of air-inflated magnetic resonance (MR) colonography for the detection of colonic lesions. MATERIALS AND METHODS: A total of 36 patients underwent both colonoscopy and air-inflated MR colonography. Breath-hold sequences (volumetric interpolated breath-hold examination (VIBE) coronal, and half-Fourier acquisition single-shot turbo spin-echo (HASTE) axial and coronal, both supine and prone) were performed with a 1.5T scanner. The detection of colonic lesions by MR colonography was then correlated with the findings from the colonoscopy performed on the same day. RESULTS: Two patients were unable to complete the MR colonography examination. Analysis was based on the results from 34 patients (17 males and 17 females, 38-70 years old, mean age = 54.9 years) who completed both examinations. MR colonography depicted two of two colonic tumors, one of one P4 (> 2 cm) polyp, one of two P2 (0.5-1 cm) polyps, and two of 11 P1 (< 0.5 cm) polyps. False-positive MR colonography interpretations were noted for one P1 polyp and two P2 polyps. The overall sensitivity, positive predictive value, and accuracy of MR colonography were 38%, 67%, and 46.2%, respectively. For the detection of endoluminal lesions > 5 mm, air-inflated MR colonography yielded a sensitivity of 75%, specificity of 93.3%, accuracy of 91.2%, positive predictive value of 60%, and negative predictive value of 96.6%. CONCLUSION: Air-inflated MR colonography is a new technique that deserves further investigation.     

Age as a predictor of hyperphosphatemia after oral phosphosoda administration for colon preparation

BACKGROUND AND AIM: It has been reported that oral phosphosoda (OPS), commonly used in bowel cleansing, may cause complications such as hyperphosphatemia and hypocalcemia. This has been observed in patients with normal kidney function and in those with renal insufficiency. Few controlled studies have been performed with respect to age on healthy subjects after OPS administration. METHODS: Seventy patients (38 men and 32 women; mean age 47 +/- 12 years, range 25-80 years) were enrolled in the present study. Half of the 90 mL total volume of OPS was ingested 18 h before colonoscopy, and the other half 6 h before the procedure. Creatinine clearance rate (CCR) and serum levels of sodium, potassium, calcium and phosphate were measured before and after OPS administration. RESULTS: After OPS administration, serum calcium and potassium were significantly lower (P < 0.05), and serum phosphate and sodium were significantly higher than pretreatment levels (P < or = 0.01). The statistically significant changes in serum sodium, potassium and calcium were within normal laboratory ranges. The mean change in serum phosphate was positively correlated with age (Pearson's r = 0.705; p < 0.001). CONCLUSION: Administration of OPS causes a significant rise in serum phosphate, even in patients with normal CCR. The elevation is significantly greater in elderly patients. Administration of OPS can be considered safe for young and middle-aged patients with normal renal function; however, it should be used with caution in elderly patients, even in those with normal CCR and serum creatinine values.     

Is transcutaneous electrical nerve stimulation an effective analgesia during colonoscopy?

OBJECTIVES—To evaluate the efficacy of transcutaneous electrical nerve stimulation (TENS) as analgesia during colonoscopy.
DESIGN—In a randomised controlled trial, patients undergoing diagnostic colonoscopy were assigned to one of three groups: standard medication only (midazolam); active TENS plus standard medication; or non-functioning TENS and standard medication. Efficacy of TENS was determined using numerical rating scores for pain and the post-procedural evaluation questionnaire.
SETTING—Patients undergoing diagnostic colonoscopy in a teaching hospital.
MAIN OUTCOME—There was no statistically significant differences between the three groups. However in the active TENS group there was a greater variation in "physical discomfort" and "psychological distress", suggesting TENS may be effective in subgroup of patients.


     

Long-lasting reduction of risk of colorectal cancer following screening endoscopy

Several studies have suggested that incidence and mortality of colorectal cancer (CRC) may be strongly reduced for up to 10 years by endoscopic screening with removal of precancerous lesions, but so far there are no data on risk reduction beyond this period. We assessed long-term reduction of CRC risk following screening endoscopy in a statewide population-based case-control study in Saarland, Germany. Lifetime history of screening endoscopy was compared between 320 cases with CRC aged 45-80 and 263 controls with other forms of cancer recruited from the same population. Potential confounding factors were controlled for by multiple logistic regression. 11% of cases compared to 27% of controls had a history of endoscopy for screening purposes (adjusted odds ratio (OR) = 0.28, 95% confidence interval (CI): 0.16-0.48). This strong risk reduction was also seen (OR = 0.41, 95% CI: 0.19-0.89) in subjects who had their last screening endoscopy more than 10 years ago (median: 18.9 years). Long term (> 10 years since last screening) risk reduction appeared to be particularly strong for advanced (Dukes C or D) CRC (OR = 0.19, 95% CI: 0.06-0.64). We conclude that risk reduction by screening endoscopy is long lasting, in particular with respect to advanced CRC.     

无痛肠镜在检查中的优势

目的通过普通肠镜与无痛肠镜的对比及分析，体现出无痛肠镜的优势。方法选择2005年1～12月病例343例，其中男151例，女192例。随机分为两组，一组是普通的肠镜检查，另一组是无痛肠镜检查。结果无痛肠镜在检查中无痛苦。不适和恐惧，使肠壁松弛有利于肠镜的顺利通过。结论通过无痛肠镜检查，能使患者在无痛苦的情况下进行检查，使检查医生能在无患者烦躁情绪的干扰下，安静地顺利地进行检查。     

ADVANTAGES OF USING THIN ENDOSCOPE‐ASSISTED ENDOSCOPIC SUBMUCOSAL DISSECTION TECHNIQUE FOR LARGE COLORECTAL TUMORS

Background: Our purpose was to evaluate the effectiveness of a newly developed non‐invasive traction technique known as thin endoscope‐assisted endoscopic submucosal dissection (TEA‐ESD) procedure for the removal of colorectal laterally spreading tumors (LST). Patients and Methods: A total of 37 LST located in the rectum and distal sigmoid colons of 37 patients were eligible for outcome analysis. Twenty‐one LST were treated with TEA‐ESD and were then retrospectively compared to 16 LST that had previously been treated with standard ESD. Tumor size, en bloc resection rate, procedure time, combined number of different electrical surgical knives used during each procedure and associated complications were evaluated in this case–control study. Results: There was no statistically significant difference in tumor size between the TEA‐ESD group and the ESD control group (43.6 ± 16 mm and 42.4 ± 14 mm, respectively). All LST were successfully resected en bloc in both groups. Procedure duration was shorter for the TEA‐ESD group than the ESD control group, although the difference was not statistically significant (96 ± 53 minutes vs 116 ± 74 minutes; P = 0.18). The percentage of cases in which only one electrical surgical knife was used during the entire procedure was significantly higher in the TEA‐ESD group compared to the ESD control group (85.7% vs 31.3%; P = 0.0005). There were no perforations in the TEA‐ESD group while the ESD control group experienced one perforation. At the present time, TEA‐ESD is limited to the rectum and distal sigmoid colon. Conclusion: It was technically easier, safer and more cost‐effective to perform ESD for LST in the rectum and the distal sigmoid colon using the newly developed TEA‐ESD traction technique.     

Surveillance interval of endoscopic examinations for colorectal cancer screening

Background: There have been a few evidence‐based studies concerning the relationship between the length of the surveillance interval of colonoscopic examinations and the risk of colorectal cancer (CRC). The aim of the present study was to assess the appropriate interval between endoscopic examinations for CRC screening in a retrospective cohort study. Methods: The cohort included subjects in whom cancer was not detected at the initial endoscopic examination and in whom endoscopic examination(s) was subsequently performed one or more times. The results of the endoscopic examinations performed in the mass screening for CRC between November 1983 and March 1999 were analyzed. The study end point was the detection of CRC and the detection rates of cancer were assessed among those who underwent examinations at various intervals between successive endoscopic examinations. Results: Among the 117 636 cohort subjects, 63 invasive cancer cases and 112 mucosal cancer cases were found. The odds ratio (OR) for invasive cancer was not significantly elevated even when the interval between successive examinations was over 5 years. The OR for mucosal or invasive cancer was significantly elevated among the subjects in whom the interval between successive examinations was over 5 years (OR, 1.71; 95% confidence interval (CI), 1.07–2.73), than among those in whom the interval was 1 year. Conclusions: Since prolongation of the interval between endoscopic examinations of up to 5 years did not result in any change in the cancer risk among persons who are at average risk for CRC, 5 years may be an adequate interval between endoscopic examinations in the mass screening for CRC.     

2型糖尿病与结直肠癌关系的研究进展

2型糖尿病患者易罹患结直肠癌，若接受胰岛素治疗，则不仅结直肠癌发病率更高，且肿瘤进展更加迅速。高胰岛素血症假说认为,异常增高的胰岛素及游离胰岛素样生长因子-1水平可促进结肠细胞增殖,最终导致结直肠癌的发生。由于结直肠癌可通过筛选试验得以早期发现,故建议2型糖尿病患者均应选择合适的筛选形式，特别是接受胰岛素治疗的患者应建议进行结肠镜检查，并且筛选间隔时间不得超过5年。