Observer variation in the detection of colorectal neoplasia on double-contrast barium enema: implications for colorectal cancer screening and training

AIM: To assess inter-observer error for the diagnosis of neoplasia on double contrast barium enema (DCBE) in the light of claims that no additional interpretative training would be needed for implementation in a national screening programme. MATERIALS AND METHODS: 10 experts, 10 consultants, and 10 experienced trainees each reported 20 DCBE studies, of which two showed cancer, three showed large polyps, four showed small polyps, and 12 were normal. Inter-observer variation was compared using odds ratios with the trainee group as reference (baseline group). RESULTS: Experts were significantly more likely to correctly identify neoplasia on DCBE than trainees. The odds of a correct diagnosis for experts were 2.79 (95% CI 2.04, 3.81) for cancer, 2.36 (1.88, 2.97) for large polyps, and 3.50 (1.98, 6.18) for small polyps. While consultants were more likely to correctly diagnose a large polyp than trainees, 1.45 (1.15, 1.84), there was no significant difference between these two groups for the correct diagnosis of either cancer, 1.24 (0.52, 2.96), or small polyps, 1.26 (0.83, 1.90). A cancer was missed by 6 (60%) experts, 9 (90%) consultants, and 8 (80%) trainees. Large polyps were missed by 4 (40%) experts, 5 (50%) consultants, and 6 (60%) trainees. There was no significant difference between any group when false positive diagnoses were considered. CONCLUSIONS: There is considerable inter-observer perceptive error for the diagnosis of neoplasia on DCBE. Experts performed significantly better than other observers but the overall standard of performance was poor, even amongst experts.     

Preoperative lymphoscintigraphy and dynamic sentinel node biopsy for staging penile cancer: results with pathological correlation

PURPOSE: We assessed the sensitivity of preoperative lymphoscintigraphy and dynamic sentinel node biopsy for staging the inguinal region of patients with penile cancer and no palpable inguinal adenopathy. MATERIALS AND METHODS: The records of 31 patients with invasive penile cancer and nonpalpable (29) or nonsuspicious (2) inguinal lymph nodes were reviewed. Preoperatively lymphoscintigraphy plus dynamic sentinel node biopsy with (99m)technetium labeled sulfur colloid and isosulfan blue dye was performed in 21 patients and dynamic sentinel node biopsy alone with blue dye only was done in 10. All patients underwent superficial lymph node dissection regardless of preoperative lymphoscintigraphy or dynamic sentinel node biopsy findings to establish pathological nodal status. RESULTS: Six of 32 groins that showed drainage on preoperative lymphoscintigraphy had inguinal node metastasis, as did 1 of 10 that was drainage negative. The sensitivity of preoperative lymphoscintigraphy drainage for cancer detection was 86%. Using dynamic sentinel node biopsy with blue dye plus radiotracer 5 sentinel lymph nodes were positive for cancer, although 2 false-negative results were obtained. Thus, the sensitivity of dynamic sentinel node biopsy per groin for cancer detection was 71%. CONCLUSIONS: In our experience preoperative lymphoscintigraphy and dynamic sentinel node biopsy as currently performed remain insufficient for detecting occult inguinal disease. Superficial lymph node dissection remains the gold standard for detecting inguinal microscopic metastasis in select patients.     

Cardiovascular effects at multi-detector row CT colonography compared with those at conventional endoscopy of the colon

PURPOSE: To compare the cardiovascular effects of computed tomographic (CT) colonography and conventional endoscopy in a group of patients undergoing both procedures. MATERIALS AND METHODS: A total of 144 patients underwent CT colonography followed by flexible sigmoidoscopy (40 patients) or colonoscopy (104 patients). Pulse, blood pressure, and oxygen saturation were measured before, during, and after the procedures. Forty patients also underwent continuous Holter electrocardiographic (ECG) monitoring. Periprocedural pain was assessed by using a handheld counting device. Outcome variables were assessed by using a combination of paired t testing and multilevel linear regression. RESULTS: When a spasmolytic was not used, CT colonography was associated with only a small increase in oxygen saturation (P =.03), while use of a spasmolytic caused an increase in pulse (mean increase, 19.9 beats per minute; P <.001) and diastolic blood pressure (mean increase, 5 mm Hg; P <.001). Compared with that at CT, oxygen saturation decreased significantly during and after colonoscopy and sigmoidoscopy (mean decrease after colonoscopy with sedation, 1.0%; P <.001). Systolic and diastolic blood pressure also decreased during and after colonoscopy (mean systolic decrease after colonoscopy with sedation, 16.6 mm Hg, P <.001; mean diastolic decrease after colonoscopy with sedation, 7.5 mm Hg, P <.001). Patients were 30.3 times more likely to develop bradycardia after endoscopy (95% CI: 2.65, 346; P =.006). Ventricular couplets were significantly higher at endoscopy than at CT in patients with a history of cardiac disease (odds ratio: 72.5 and 95% CI: 4.56, 1,153 at CT vs odds ratio: 14.6 and 95% CI: 0.96, 222 at endoscopy; P =.002). Patients were 1.89 times more likely to register pain during colonoscopy than during CT (95% CI: 1.06, 3.38; P =.03). CONCLUSION: CT colonography had no significant cardiovascular effect other than spasmolytic-induced tachycardia. Endoscopy-and colonoscopy in particular-causes cardiovascular effects that are largely related to sedation. CT colonography is less painful than colonoscopy and is comparable to flexible sigmoidoscopy.     

Clinically detectable copy number variations in a Canadian catchment population of schizophrenia

Copy number variation (CNV) is a highly topical area of research in schizophrenia, but the clinical relevance is uncertain and the translation to clinical practice is under-studied. There is a paucity of research involving truly community-based samples of schizophrenia and widely available laboratory techniques. Our objective was to determine the prevalence of clinically detectable CNVs in a community sample of schizophrenia, while mimicking typical clinical practice conditions. We used a brief clinical screening protocol for developmental features in adults with schizophrenia for identifying individuals with 22q11.2 deletions and karyotypically detectable chromosomal anomalies in 204 consecutive patients with schizophrenia from a single Canadian catchment area. Twenty-seven (13.2%) subjects met clinical criteria for a possible syndrome, and 26 of these individuals received clinical genetic testing. Five of these, representing 2.5% of the total sample (95% CI: 0.3%-4.6%), including two of ten patients with mental retardation, had clinically detectable anomalies: two 22q11.2 deletions (1.0%), one 47, XYY, and two other novel CNVs - an 8p23.3-p23.1 deletion and a de novo 19p13.3-p13.2 duplication. The results support the utility of screening and genetic testing to identify genetic syndromes in adults with schizophrenia in clinical practice. Identifying large, rare CNVs (particularly 22q11.2 deletions) can lead to significant changes in management, follow-up, and genetic counselling that are helpful to the patient, family, and clinicians.     

Investigation of breast cancer using two‐dimensional MRS

Proton (¹H) MRS enables non‐invasive biochemical assay with the potential to characterize malignant, benign and healthy breast tissues. In vitro studies using perchloric acid extracts and ex vivo magic angle spinning spectroscopy of intact biopsy tissues have been used to identify detectable metabolic alterations in breast cancer. The challenges of ¹H MRS in vivo include low sensitivity and significant overlap of resonances due to limited chemical shift dispersion and significant inhomogeneous broadening at most clinical magnetic field strengths. Improvement in spectral resolution can be achieved in vivo and in vitro by recording the MR spectra spread over more than one dimension, thus facilitating unambiguous assignment of metabolite and lipid resonances in breast cancer. This article reviews the recent progress with two‐dimensional MRS of breast cancer in vitro, ex vivo and in vivo. The discussion includes unambiguous detection of saturated and unsaturated fatty acids, as well as choline‐containing groups such as free choline, phosphocholine, glycerophosphocholine and ethanolamines using two‐dimensional MRS. In addition, characterization of invasive ductal carcinomas and healthy fatty/glandular breast tissues non‐invasively using the classification and regression tree (CART) analysis of two‐dimensional MRS data is reviewed. Copyright © 2008 John Wiley & Sons, Ltd.     

Do clinical practice guidelines reflect research evidence?

OBJECTIVES: To examine whether existing clinical practice guidelines (CPGs) for cholesterol testing reflect research evidence and hence may control or reduce costs while maintaining or improving the quality of care. METHODS: A systematic search for published and unpublished cholesterol testing CPGs and independent critical appraisal of the CPGs by two researchers using a standard checklist. RESULTS: In four of the five CPGs analysed, the link between the research evidence and the recommendations was not maintained. The appraisal, local experience and the literature all suggest that panel composition is an important explanation, in that the greater the involvement of clinical experts in the development process of the CPGs, the less the recommendations reflected the research evidence. Even though their participation is important for CPG uptake, clinical expert panels appear to have difficulty limiting CPGs to research-based recommendations. CONCLUSIONS: Existing cholesterol testing CPGs are unlikely to improve the quality of care while controlling or reducing costs. The problem lies not with guideline implementation but with the guidelines themselves. It is unclear how best to ensure that recommendations reflect research evidence but this is likely to require significant and progressive changes to the current guideline development process, including a redefinition of the clinical experts' role.