Background/Aim: Noninvasive fecal occult blood tests (FOBTs) are recommended by current guidelines for colorectal cancer (CRC) screening. Our aim was to assess the diagnostic performance of traditional guaiac-based FOBTs (gFOBT) and new-generation immunochemical FOBTs (iFOBT) in CRC screening by carrying out a systematic review and meta-analysis. Patients and Methods: PubMed, Embase, Cochrane Library, and Web of Science were searched for eligible articles published before February 17, 2020. Three independent investigators conducted study assessment and data extraction. Diagnosis-related indicators for use of FOBTs in the detection of CRC (as the endpoint) in a screening setting were summarized, and further stratified by the type of FOBT (gFOBT vs. iFOBT). STATA software was used to conduct the metaanalysis. Pooled sensitivities and specificities were calculated using a random-effects model. Hierarchical summary receiver operating characteristic curves were plotted and area under the curves (AUC) were calculated. Results: The electronic search identified 573 records after duplicates were removed, of which 75 full-text articles were assessed for eligibility. Finally, a total of 31 studies were eligible for the meta-analysis. In the ROC comparison test, there was a statistically significant difference in the performance of gFOBT and iFOBT tests, with AUC=0.77 (95% confidence intervaI=0.75-0.79) and AUC=0.87 (95% confidence intervaI=0.85-0.88), respectively (p=0.0017). In formal meta-regression, test brand did not prove to be a significant study-level covariate that would explain the observed heterogeneity between the studies. Conclusion: New-generation iFOBTs were found to have a significantly higher diagnostic performance as compared with gFOBTs, advocating the use of only fecal immunochemical tests in all newly implemented CRC screening programs.Colorectal cancer (CRC) is the third most common cancer worldwide, with over 1.85 million new cases and over 880,000 deaths occurring in 2018 (1). Population-based screening offers an opportunity for primary prevention and early detection of CRC, with a favorable impact on mortality (2, 3). A wide variety of screening tests are available for CRC, the most widely used being tests for fecal occult blood (FOBT). The use of FOBT was shown to reduce cancer mortality in five large randomized trials (4-8). Several international and national guidelines currently recommend that both women and men at an average risk should undergo organized screening for advanced adenoma and CRC (9).For detection of FOB, guaiac-based test (gFOBT) and fecal immunochemical test (FIT or iFOBT) are commercially available. The guaiac-based tests utilize the pseudoperoxidase activity of hemoglobin (Hb; free or intact), whereby guaiac is oxidized by hydrogen peroxidase. Because this reaction takes place with any peroxidase present in stool, gFOBT tests are non-specific to human Hb, with interference by any foodstuffs with peroxidase content, by certain chemicals or even medications (9, 10). Based on a com...

Previous randomized studies suggest that fecal occult blood test (FOBT) screening can reduce mortality from colorectal cancer (CRC). Our aim was to review the current status of FOBTs in CRC screening. FOB is measured using either the traditional guaiac-based tests or more recently introduced fecal immunochemical tests (FITs). FITs have several advantages over guaiac-based FOBTs, including higher sensitivity and specificity, resulting in improved clinical performance and higher efficiency. Another advantage in population screening according to European Guidelines for quality assurance in CRC screening is that FITs can be automated and user can adjust the cutoff at which a positive result is reported. In population-based screening, all those testing positively with any FOBT should be referred for colonoscopy. Conclusion: Although a plethora of FOBTs are available on the market, relatively few have been extensively tested for clinical sensitivity and specificity in CRC screening. Current data imply that new FITs have superior test characteristics as compared with guaiac-based FOBTs. The latest development in the field is represented by the proteomic-based tests that may further reduce false-negative rates in CRC screening. Simple stool sample preservation and automatic analysis are other important issues in population-based screening for CRC. Colorectal cancer (CRC) is the third most common cancer worldwide, with over 1.3 million new cases and over 600,000 deaths each year (1). In Finland, the incidence of CRC is lower than in many Western countries but mortality is quite similar, reflecting a mortality-to-incidence ratio disparity in Finland. During the 3-year period of 2015 to 2017, incident CRC was encountered in 4,577 women and in 5,131 in men, with an estimated annual average of 3,236 new CRC cases (2). After lung cancer, CRC is the second most common cause of cancer deaths among men and women combined in Finland (2). The majority of CRCs develop from adenomas or adenomatous polyps and several studies have shown the efficacy of screening for detection of large adenomas. CRC screening can achieve the goals of both primary prevention (by detecting cancer precursors: polyps, adenomas) and secondary prevention (by detecting early cancers) (3, 4). Thus, organized CRC screening offers a possibility for cancer prevention and early detection of cancer, with reduced mortality (5, 6). Although a plethora of fecal occult blood test (FOBT) are available on the market, relatively few of them have been extensively tested for clinical sensitivity and specificity in CRC screening. The main aim for the use of FOBTs is to reduce CRC mortality (7-11). European Guidelines for quality assurance in CRC screening recommend fecal immunochemical tests (FITs) because FITs have improved test characteristics compared to guaiac-based FOBTs (gFOBTs) (12) (Table I). The most commonly used CRC screening tests include flexible sigmoidoscopy, colonoscopy and FOBT (13, 14). Lin et al. reviewed literature and found four randomized clinical trials...

Background/Aim: Although, acute appendicitis (AA) and nonspecific abdominal pain (NSAP) are the most common diagnoses among secondary care patients with acute abdominal pain, the diagnostic performance of leucocyte count (LC) in DS (Diagnostic Score) model is rarely considered. Patients and Methods: As an extension of the World Organisation of Gastro-Enterology Research Committee (OMGE) acute abdominal pain study, 1,333 patients presenting with acute abdominal pain were included in the study. The clinical history and diagnostic symptoms (n=22), signs (n=14) and tests (n=3) in each patient were recorded in detail, and the collected data were related with the final diagnoses of the patients. Results: In the ROC comparison test, there was no statistically significant difference in the performance of DS LC-(DS without LC) and DS LC+ (DS with LC). The highest sensitivities of the DS LCand DS LC+ tests for detecting AA were 86% (95%CI=81-90%) and 87% (95%CI=82-91%), respectively. The highest specificities of the DS LC-and DS LC+ tests for detecting AA were 98% (95%CI=97-99%) and 98% (95%CI=96-99%), respectively. Conclusion: DS could assist the clinician in differentiating AA from NSAP and other causes of acute abdominal pain. Importantly, LC does not improve the diagnostic performance of a DS in AA.We have studied acute abdominal pain in connection with the survey on acute abdominal pain by the Research Committee of the World Organization of Gastroenterology (OMGE) (1) and investigated the diagnostic performance of history-taking and clinical examination in acute appendicitis (AA) (2), nonspecific abdominal pain (NSAP) (3), acute small bowel obstruction (4) and acute renal colic (5). Given that AA and NSAP are the most common diagnoses among secondary care patients with acute abdominal pain, the diagnostic performance of history-taking, clinical examination and possible diagnostic score (DS) is extremely important. However, the differential diagnosis of AA and NSAP is not always easy due to many similarities in the clinical presentation at the onset and many cases may be misdiagnosed in the initial diagnostic setting. Although, there is some DS models available (2, 6-10) in the diagnosis of acute abdominal pain (AAP) there is continuing debate on the shortcomings of the DS models and we thus aimed to examine the performance of our DS model i) without leucocyte count (DS LC-) and ii) with leucocyte count (DS LC+ ). Patients and MethodsCriteria for inclusion in this study and the diagnostic criteria were those set out by the OMGE Committee (1). There were 636 males (47.7%) and 697 females (52.3%) with a mean age (±SD) of 38.0±22.1 years (Table I).The clinical findings in each patient were recorded in detail (Tables II and III), using a predefined structured data collection sheet. The disease history was recorded and categorised as shown in Tables II and III. The examination of the clinical symptoms, signs and tests were conducted using a standard technique and the results were graded positive or negative (Tables II and I...