Extent Of Dissemination Research Articles

The bacterial and archaeal communities of flies, manure, lagoons, and troughs at a working dairy.

Fundamental investigations into the location, load, and persistence of microbes, whether beneficial or detrimental, are scarce. Many questions about the retention and survival of microbes on various surfaces, as well as the load necessary for spread, exist. To answer these questions, we must know more about where to find various microbes and in what concentrations, the composition of the microbial communities, and the extent of dissemination between various elements. This study investigated the diversity, composition, and relative abundance of the communities associated with manure, lagoons, troughs, house flies, and stable flies present at a dairy, implementing two different free-stall management systems: flow-through and cross-vent. Shotgun metagenomics at the community level was used to compare the microbiomes within the dairy, allowing confident interpretation at the species level. The results showed that there were significant difference in microbial composition between not only each of the dairy elements but also management styles. The primary exceptions were the microbiomes of the house fly and the stable fly. Their compositions heavily overlapped with one another, but interestingly, not with the other components sampled. Additionally, both species of flies carried more pathogens than the other elements of the dairy, indicating that they may not share these organisms with the other components, or that the environments offered by the other components are unsatisfactory for the survival of some pathogens.. The lack of overlapping pathogen profiles suggests a lack of transfer from flies to other dairy elements. Dairy health data, showing a low incidence of disease, suggests minimal sharing of bacteria by the flies at a level required for infection, given the health program of this dairy. While flies did carry a multitude of pathogenic bacteria, the mere presence of the bacteria associated with the flies did not necessarily translate into high risk leading to morbidity and mortality at this dairy. Thus, using flies as the sole sentinel of dairy health may not be appropriate for all bacterial pathogens or dairies.

Advancements in Retinoblastoma Treatment: Unraveling the Potential of Intravitreal Chemotherapy.

Retinoblastoma necessitates urgent attention due to itspotential fatality if untreated. Multiple treatment options are available and should be employed according to size, location, and the extent of dissemination. This reviewemphasizes the need for increased awareness, advanced diagnostic tools, and innovative treatmentapproaches, especially intravitreal chemotherapy (IVitC) to address the diverse manifestations and aggressive nature of retinoblastoma.Timely diagnosis and commitment to treatment are pivotal, as delays and reluctance to undergo enucleationcontribute to unfavorable outcomes. The evolving treatment landscape, spanning from traditionalinterventions to modern targeted therapies such as intravitreal melphalan, holds promise for improvedoutcomes. While the intravitreal approach presents challenges, ongoing research aims to establish itsdefinitive role in retinoblastoma treatment. In the treatment of retinoblastoma, IVitCraises considerations about side effects. The risk of tumor spread beyond the eye is rare, emphasising thepotential of IVitC in carefully selected cases. Intravitreal injections exhibit fewer localadverse effects compared to intra-arterial chemotherapy, with careful measures reducing significant ocularcomplications. The evaluation of ocular toxicity, particularly with melphalan, underscores the importance ofa nuanced approach to achieve the right balance between therapeutic efficacy and ocular safety. This comprehensive analysis of studies on IVitC and its ocular and systemic complications provides valuable insights for enhanced patient care. The review concludes with a focus on balancingsafety and efficacy in local chemotherapeutic drugs, highlighting the need for thoughtful measures andcontinued research to optimise treatment modalities globally.

Severe Sporotrichosis Caused by Sporothrix brasiliensis: Antifungal Susceptibility and Clinical Outcomes

Itraconazole is the first choice for treating sporotrichosis. Amphotericin B is indicated for severe and disseminated forms. The aim of the study was to evaluate the antifungal susceptibility of Sporothrix brasiliensis strains isolated from patients with severe sporotrichosis treated with amphotericin B and correlate with clinical outcomes. Clinical and epidemiological data were obtained from severe sporotrichosis cases caused by S. brasiliensis. Antifungal susceptibility tests against amphotericin B, itraconazole, terbinafine, posaconazole, and 5-flucytosine were performed. Moreover, possible synergisms between amphotericin B and posaconazole or 5-flucytosine were assessed. Relationships between clinical and laboratorial data were then analyzed. Forty-six S. brasiliensis isolates from 37 patients were studied. Clinical forms included disseminated (94.6%) and disseminated cutaneous sporotrichosis (5.4%). The median treatment time was 784 days (range: 7 to 3115 days). Cure occurred in 45.9% of the cases and death due to sporotrichosis in 24.3%. Forty-three (93.5%) S. brasiliensis isolates were classified as wild-type for all the antifungals tested according to their in vitro antifungal susceptibility. There was no synergism for the combinations studied. Finally, we found no association between higher Minimal Inhibitory Concentration (MIC) values of amphotericin B or itraconazole with unfavorable outcomes; however, there were higher MIC values of itraconazole in strains isolated from alcoholic patients. Possibly, clinical factors, such as the extent of dissemination, immunosuppression, and late treatment onset, are the main determinants of patient outcomes, rather than antifungal resistance. The current study suggests that the need to use amphotericin B therapy is not associated with the emergence of S. brasiliensis resistant strains.

Value of [68Ga]Ga-somatostatin receptor PET/CT in the grading of pulmonary neuroendocrine (carcinoid) tumours and the detection of disseminated disease: single-centre pathology-based analysis and review of the literature

BackgroundAlthough most guidelines suggest performing a positron emission tomography/computed tomography (PET/CT) with somatostatin receptor (SSTR) ligands for staging of pulmonary carcinoid tumours (PC), only a limited number of studies have evaluated the role of this imaging tool in this specific patient population. The preoperative differentiation between typical carcinoid (TC) and atypical carcinoid (AC) and the extent of dissemination (N/M status) are crucial factors for treatment allocation and prognosis of these patients. Therefore, we performed a pathology-based retrospective analysis of the value of SSTR PET/CT in tumour grading and detection of nodal and metastatic involvement of PC and compared this with the previous literature and with [18F]FDG PET/CT in a subgroup of patients.MethodsSSTR PET/CT scans performed between January 2007 and May 2020 in the context of PC were included. If available, [18F]FDG PET/CT images were also evaluated. The maximum standardized uptake (SUVmax) values of the primary tumour, of the pathologically examined hilar and mediastinal lymph node stations, as well as of the distant metastases, were recorded. Tumoural SUVmax values were related to the tumour type (TC versus AC) for both SSTR and [18F]FDG PET/CT in diagnosing and differentiating both tumour types. Nodal SUVmax values were compared to the pathological status (N+ versus N−) to evaluate the diagnostic accuracy of SSTR PET/CT in detecting lymph node involvement. Finally, a mixed model analysis of all pathologically proven distant metastatic lesions was performed.ResultsA total of 86 SSTR PET/CT scans performed in 86 patients with PC were retrospectively analysed. [18F]FDG PET/CT was available in 46 patients. Analysis of the SUVmax values in the primary tumour showed significantly higher SSTR uptake in TC compared with AC (median SUVmax 18.4 vs 3.8; p = 0.003) and significantly higher [18F]FDG uptake in AC compared to TC (median SUVmax 5.4 vs 3.5; p = 0.038). Receiver operating characteristic (ROC) curve analysis resulted in an area under the curve (AUC) of 0.78 for the detection of TC on SSTR PET/CT and of 0.73 for the detection of AC on [18F]FDG PET/CT. A total of 267 pathologically evaluated hilar and mediastinal lymph node stations were analysed. ROC analysis of paired SSTR/[18F]FDG SUVmax values for the detection of metastasis of TC in 83 lymph node stations revealed an AUC of 0.91 for SSTR PET/CT and of 0.74 for [18F]FDG PET/CT (difference 0.17; 95% confidence interval − 0.03 to 0.38; p = 0.10). In a sub-cohort of 10 patients with 12 distant lesions that were pathologically examined due to a suspicious aspect on SSTR PET/CT, a positive predictive value (PPV) of 100% was observed.ConclusionOur findings confirm the higher SSTR ligand uptake in TC compared to AC and vice versa for [18F]FDG uptake. More importantly, we found a good diagnostic performance of SSTR PET/CT for the detection of hilar and mediastinal lymph node metastases of TC. Finally, a PPV of 100% for SSTR PET/CT was found in a small sub-cohort of patients with pathologically investigated distant metastatic lesions. Taken together, SSTR PET/CT has a very high diagnostic value in the TNM assessment of pulmonary carcinoids, particularly in TC, which underscores its position in European guidelines.

TPR1, a novel rifampicin derivative, demonstrates efficacy alone and in combination with doxycycline against the NIAID Category A priority pathogen Francisella tularensis.

Background Francisella tularensis is a highly virulent and contagious Gram-negative intracellular bacterium that causes the disease tularaemia in mammals and is classified as a Category A priority pathogen.MethodsWe utilized a systematic analysis of antibacterial potency, extent of dissemination by analysis of bacterial burden in a secondary vital organ, and survival rates to assess the efficacy of a novel rifampicin derivative, TPR1. The efficacy of TPR1 was evaluated alone and in combination with the standard of care drug, doxycycline, against type A F. tularensis Schu S4 using a lethal pulmonary model of infection in mice.ResultsTPR1 has an MIC value range of 0.125–4 mg/L against reference laboratory strain Schu S4 and a panel of clinical strains. TPR1 alone reduced the bacterial burden in the lungs and spleen at 40 mg/kg and 80 mg/kg, and no antagonism was observed when co-administered with doxycycline. Dosing at 40 mg/kg doxycycline reduced the bacterial burden by 1 log10 cfu in the lungs and 4 log10 cfu in the spleen in comparison to untreated controls. Co-administration of TPR1 and doxycycline demonstrated efficacy upon treatment withdrawal after 4 days of treatment, and 100% survival.ConclusionsSignificantly, TPR1 demonstrated efficacy when delivered alone and in combination with doxycycline, which provides compelling evidence of a superior treatment strategy that would normally rely on a single chemotherapeutic for efficacy. In addition, this work substantiates the use of rifampicin derivatives as a platform for the development of novel treatments to other bacterial agents in addition to tularaemia.

Asset Dissemination Through Dealer Markets

In over-the-counter markets for assets, such as bonds and securitizations, large volumes can be split into smaller pieces and gradually sold to several final investors with the intermediation of multiple dealers. This paper proposes a model to study this process, called asset dissemination. A dealer buys several units of an asset from a customer and then sells some units to the dealer’s customers and to a second dealer, who sells to the second dealer’s customers and to a third dealer, and so on. The extent of dissemination is measured by the number of dealers involved and the total customer demand served. We show that asymmetric information on customer demand hinders both dimensions of dissemination. We also study how the quantity to disseminate and the dealers’ funding costs impact dissemination and the prices and quantities in interdealer transactions. This paper was accepted by Gustavo Manso, finance.

Evaluating the dissemination and scale-up of two evidence-based parenting interventions to reduce violence against children: study protocol

BackgroundEliminating violence against children is a prominent policy goal, codified in the Sustainable Development Goals, and parenting programs are one approach to preventing and reducing violence. However, we know relatively little about dissemination and scale-up of parenting programs, particularly in low- and middle-income countries (LMICs). The scale-up of two parenting programs, Parenting for Lifelong Health (PLH) for Young Children and PLH for Parents and Teens, developed under Creative Commons licensing and tested in randomized trials, provides a unique opportunity to study their dissemination in 25 LMICs.MethodsThe Scale-Up of Parenting Evaluation Research (SUPER) study uses a range of methods to study the dissemination of these two programs. The study will examine (1) process and extent of dissemination and scale-up, (2) how the programs are implemented and factors associated with variation in implementation, (3) violence against children and family outcomes before and after program implementation, (4) barriers and facilitators to sustained program delivery, and (5) costs and resources needed for implementation.Primary data collection, focused on three case study projects, will include interviews and focus groups with program facilitators, coordinators, funders, and other stakeholders, and a summary of key organizational characteristics. Program reports and budgets will be reviewed as part of relevant contextual information. Secondary data analysis of routine data collected within ongoing implementation and existing research studies will explore family enrolment and attendance, as well as family reports of parenting practices, violence against children, child behavior, and child and caregiver wellbeing before and after program participation. We will also examine data on staff sociodemographic and professional background, and their competent adherence to the program, collected as part of staff training and certification.DiscussionThis project will be the first study of its kind to draw on multiple data sources and methods to examine the dissemination and scale-up of a parenting program across multiple LMIC contexts. While this study reports on the implementation of two specific parenting programs, we anticipate that our findings will be of relevance across the field of parenting, as well as other violence prevention and social programs.

Asset Dissemination Through Dealer Markets

In over-the-counter markets for assets such as bonds or securitizations, large volumes can be split into smaller pieces and gradually sold to several final investors with the intermediation of multiple dealers. This paper proposes a model to study this process, called “asset dissemination”. A dealer buys several units of an asset from a customer, then sells some units to his customers and to a second dealer, who sells to his customers and a third dealer, and so on. The extent of dissemination is measured by the number of dealers involved and the total customer demand served. We show that asymmetric information on customer demand hinders both dimensions of dissemination. We also study how the quantity to disseminate and the dealers’ funding costs impact dissemination and the prices and quantities in interdealer transactions.

Quantifying Bluetongue Virus in Adult <I>Culicoides</I> Biting Midges (Diptera: Ceratopogonidae)

A TissueLyser system (QIAGEN) was used to rapidly and accurately estimate bluetongue virus "loads" in individual adult Culicoides sonorensis Wirth & Jones (Diptera: Ceratopogonidae). The optimized homogenization program that was developed, involved shaking insects for 1 min at 25 Hz with 2- or 3-mm stainless steel ball bearings. This program was used to measure the quantities of bluetongue virus present in insects that had either been inoculated or had ingested a viremic bloodmeal through an artificial membrane. The virus titers obtained using either infection technique and the optimized program did not differ significantly from those obtained using a polypropylene motor-driven pestle, a method that is currently in common use for studies of vector competence). The advantages of the new method, as a rapid means of detecting fully disseminated infections in individual field-caught flies, are discussed. Its use is compared with the processing of pools of Culicoides by conventional methods, where the extent of dissemination of the virus is unknown and could wrongly implicate species that are of low importance in transmission.

Primary Appendiceal Malignancy: A Clinicopathologic Study

Primary appendiceal cancer is a rare neoplasm. We analyzed the clinicopathologic characteristics and clinical outcomes of patients with primary appendiceal cancer treated at Buddhist Tzu Chi General Hospital in Eastern Taiwan. We reviewed the medical records of patients who had appendectomy at our hospital over a 10-year period and studied those who had histologically proven malignant appendiceal neoplasms. We treated eight such patients: seven males and one female. Their median age was 66 years (range, 59-78 years). There were three mucinous adenocarcinomas, two colonic type adenocarcinomas, and three adenocarcinoids. No patient was diagnosed correctly before surgery, and five (62.5%) had a preoperative diagnosis of acute appendicitis. Operative procedures included right hemicolectomy or partial colectomy in four, debulking and right hemicolectomy in three, and appendectomy only in one. With a mean follow-up of 64 months (range, 3-132), patients with adenocarcinoid lesions had better prognosis than those with adenocarcinomas. The important prognostic factors of primary appendiceal cancer included histologic subtypes and the extent of dissemination. In our series, palliative resection for disseminated lesions with or without additional chemotherapy resulted in long-term survival.

Disseminated cysticercosis involving orbit, brain and subcutaneous tissue

Human cysticercosis is caused by dissemination of embryos of Taenia solium from the intestine via the hepatoportal system to the tissues and organs of the body. We report, probably the first case, where orbital cysticercosis was associated with multiple Cysticercus cellulosae cysts in the brain and subcutaneous tissue. Thorough screening for all the sites of involvement by the cyst is extremely useful for knowing the extent of dissemination, infection control, and for epidemiological purposes.

The Impact of Technology Use in Special Education Field Experience on Preservice Teachers' Perceived Technology Expertise

This article outlines the results of an exploratory study designed to measure changes in the awareness of preservice teachers concerning technology for students with disabilities. A pretest-posttest survey collected data on (a) awareness of the types of instructional technology available for students with disabilities, (b) ability to integrate technology into the classroom, (c) knowledge of the operation of computers and peripherals, (d) knowledge of technology available for assessment, and (e) extent of dissemination of new knowledge to colleagues. Results of this study indicated that participation in a technology-rich field experience increases the likelihood that preservice special educators will perceive an increase in (a) knowledge concerning the appropriate use of technology for students with disabilities, (b) the use of technology to facilitate student learning, and (c) the use of technology as a teacher tool.

Breaching the mucosal barrier by stealth: an emerging pathogenic mechanism for enteroadherent bacterial pathogens.

The clinical and molecular understanding of bacterial diseases of the gastrointestinal tract, developed largely over the past 50 years, has led to our current assignment of these causative agents into an evolving set of mechanistic categories (see Table ​Table1).1). Early studies revealed that some organisms (Staphylococcus aureus among them) produce toxins in contaminated foods and that, upon ingestion, these preformed toxins trigger a rapid-onset, net jejunal secretion of electrolytes and water, typically lasting less than 24 hours. In these illnesses, the causative organism need not be present in the intestine. In contrast, the “enterotoxigenic” pathogens, typified by Vibrio cholerae and enterotoxigenic Escherichia coli (ETEC), are noninflammatory and must colonize the gastrointestinal tract in order to deliver toxins to the mucosa. These toxins typically effect cAMP- or cGMP-mediated net Cl– secretion, often resulting in a large-volume diarrhea. Recent studies of certain strains of Bacteroides fragilis indicate that these agents can serve as large bowel mediators of enterotoxigenic disease via a toxin that disrupts the mucosal barrier (1). Table 1 Pathogenic mechanisms used by diarrheogenic bacteria Another long-recognized grouping of enteric bacterial diseases is the “invasive” category, which can be subdivided based upon the extent of dissemination within the host. The most superficial invaders, Shigella spp. and enteroinvasive E. coli, have similar, if not identical, virulence properties. These organisms invade the epithelium of the colon and terminal ileum, spread intercellularly via actin-filament projections (2), and cause focal microulcerations of the ileocecal mucosa. The submucosal group is exemplified by Yersinia enterocolitica and Yersinia pseudotuberculosis, which transcytose across the mucosal epithelium and proceed to the regional lymph nodes, causing severe abdominal pain and, occasionally, mesenteric lymphadenitis. Recent clinical and experimental data suggest that Campylobacter jejuni is an invasive pathogen that can translocate across the mucosa, and that may survive submucosally, but does not typically reach the bloodstream (3). The third invasive subgroup is typified by certain Salmonella serovars (e.g., Typhi and Paratyphi) that invade and translocate across the epithelium. These organisms enter and apparently survive for many hours in submucosal monocytes, which may serve to transport these pathogens to distal sites in the host (e.g., spleen, liver, and bone marrow). The characterization of a previously unrecognized group of pathogenic E. coli (i.e., enteropathogenic E. coli [EPEC], enteroaggregative E. coli [EAEC], diffusely adherent E. coli [DAEC], and enterohemmorhagic E. coli [EHEC]) since the 1950s has led to the establishment of the enteroadherent category of disease. These agents colonize the small and/or large intestine, do not appear to be invasive to any appreciable extent in vivo, and, with the exception of shiga-like toxins of EHEC, are not known to elaborate any of the classical enterotoxins, yet they cause diarrheal illness. Classical EPEC serotypes are known to induce “pedestal” or “cup-like” rearrangements, referred to as attaching and effacing lesions, of epithelial cell membranes. The attaching bacteria erode the microvilli via a rearrangement of cytoskeletal actin into host membrane pedestal structures that support the organism. EAEC and DAEC display characteristic, but different, adherence patterns on cultured intestinal cells and have not been shown to cause any striking membrane effacement. Although certain aspects of EPEC pathogenesis, such as adherence and the attaching and effacing phenotype, have been studied elegantly and in detail (4), the mechanisms by which these and other enteroadherent organisms induce inflammation and diarrhea have only recently started to emerge (5). Salmonella enterica serovar Typhimurium (now abbreviated S. Typhimurium) have previously been considered members of the invasive category, because of their invasiveness in cultured cells and their ability to cause a typhoid-like illness in mice. Indeed, S. Typhimurium may occasionally be isolated from extraintestinal sites in humans including the bloodstream, particularly in immunocompromised hosts. However, these pathogens are more typically associated in humans with diarrheal illness of mild to moderate severity accompanied by fever and the appearance of fecal leukocytes. Although S. Typhimurium may trigger limited invasion of the intestine, as may occur with other enteroadherent pathogens, mucosal invasion does not appear to be a prominent aspect of normal disease. As now shown in this issue of the JCI (6), S. Typhimurium appear to be prime examples of organisms that cause diarrheal disease through a general mechanism that may characterize many bacteria commonly placed in the enteroadherent category of intestinal diseases.

Modeling of acute experimental peritonitis.

A new method of modeling of acute diffuse peritonitis was designed and tested. The method reproduces clinical picture of severe purulent process in the abdominal cavity with clear phasic dynamics and uniform (in their nature and extent of dissemination) pathological reactions, which improves reliability of experimental data.

Progress in total quality management: evidence from Australasia

States that, although there has been considerable progress with the implementation of total quality management in Australia and New Zealand over the past 15 years since it was pioneered in the manufacturing sector, there is still not a widespread acceptance and implementation of it. As a result, while the best companies in these countries are achieving high levels of competitiveness, the bulk of companies are still reporting mediocre performance in critically important areas such as customer satisfaction. Details how some of Australia and New Zealand’s leading companies have implemented quality improvement initiatives. Reports on a large survey of companies showing that on average, self‐reported measures of employee morale, customer satisfaction and the extent of dissemination of customer requirements throughout a workforce are particular areas for improvement.

Clinical Features and Outcome of Eleven Patients with Disseminated Bacille Calmette-Guérin (BCG) Infection

Disseminated BCG infection is a very rare complication of BCG vaccination. This study presents 11 patients with such complication. The underlying disease in eight of the 11 patients was primary imm...

Dissemination and use of research findings in nursing practice.

This study built on two previous studies (Brett, 1987; Coyle & Sokop, 1990) that found no significant relationships between use of nursing research and nursing education level. These two studies had fewer than 5 per cent of their subjects with master's degrees in nursing. The new population studied had 49 per cent master's prepared nurses, which provided the necessary foundation to expand the examination of the relationship of higher education and use of research findings among nurses. Whereas the overall extent of dissemination and use of research findings among nurses in the sample was similar to that of the two previous studies, it was found that nurses with a master's degree reported higher utilization than those with a bachelor's degree. This finding suggests a unique and critical role for the master's-prepared nurse in the dissemination and use of research findings in the practice setting.

The Stanford faculty development program: A dissemination approach to faculty development for medical teachers

The Stanford Faculty Development Program, designed to improve the instructional skills of clinical teachers, uses a dissemination model to provide faculty development activities for medical schools across the country. Selected clinical faculty attend a month‐long training program at Stanford University Medical Center and then return to their home institutions to conduct seminars for their fellow faculty and for residents in one of three content areas: (a) principles and skills of clinical teaching, (b) the teaching of medical decision making, or (c) the teaching of clinical preventive medicine. Faculty from institutions affiliated with over one quarter of U.S. medical schools have participated in the program. From 1986 through 1991, the program has trained 67 seminar facilitators from 47 institutions who have then conducted training for over 500 faculty and 200 residents. The extent of dissemination indicates that this approach provides a feasible mechanism for delivering faculty development in a wide var...

Histological grade and steroid receptor content of primary breast cancer--impact on prognosis and possible modes of action.

The clinical course of breast cancer was related to degree of anaplasia (DA) and steroid receptor (SR) content of primary tumours in 743 patients (pts) with clinical recurrence, initially enrolled in the DBCG-77 protocols. The oestrogen receptor (ER) and the progesterone receptor (PgR) content was known in 110 and 67 pts. The recurrence-free interval, survival after recurrence, and the overall survival were all prolonged in patients with well differentiated tumours or with high SR content. The tumour growth rates were estimated as clinical rates of progression (i.e., the time elapsed from a single distant metastasis until dissemination). The progression rate was prolonged in relatively well differentiated as well as in receptor rich tumours. The extent of dissemination, as indicated by the number of metastatic sites, was not associated with either DA or SR content. However, the anatomical distribution of metastases varied with both DA and SR content: signs of poor prognosis (high DA or low SR content) were associated with occurrence of visceral metastases. In contrast, SR rich tumours had a propensity for recurrence in bone. The results suggest that the impact on prognosis of the features examined here includes both variations in growth rate and metastatic pattern.

Roche RIA and Abbott EIA carcinoembryonic antigen assays compared.

We have evaluated Roche Diagnostics' RIA-CEA and Abbott Diagnostics' EIA-CEA methods for precision, normal reference interval, concordance, and correlation of malignant disease with increase in carcinoembryonic antigen (CEA) in plasma. In examining concordance, we used data on 138 patients with primary carcinomas of the breast, colon, lung, or pancreas, each further classified by extent of dissemination. We find the two methods to be comparably precise. The respective upper reference limits of normal for the Roche and Abbott methods were determined to be 5.0 micrograms/L and 4.6 micrograms/L. The regression equation for a log transformation of the 177 data points is y = 0.966x + 0.03, where x = Roche and y = Abbott, with a correlation coefficient of 0.948. According to the criteria we used, the concordance was 78.7%. The largest discordance was observed in widely disseminated disease states and in cancers of the colon and pancreas. Paired data analysis of discordance indicated greater increases in apparent CEA by the Abbott method in most colon cancers with liver involvement; six of the eight discordant pancreatic cancers had higher Roche-CEA values. CEA heterogeneity and the role of the liver in CEA metabolism appear to contribute to the observed differences. We show why the two methods should not be used interchangeably, and that baseline values for CEA must be established for each method.