Prevalence and predictors of airflow obstruction in an HIV tertiary care clinic in Montreal, Canada: a cross-sectional study.

OBJECTIVES: The reported prevalence of chronic obstructive pulmonary disease (COPD) in people living with HIV (PLWHIV) varies widely. Our objective was to estimate the prevalence of airflow obstruction and COPD in unselected PLWHIV and identify characteristics that increase the risk of nonreversible airflow obstruction in order to guide case finding strategies for COPD. METHODS: All adults attending the Chronic Viral Illness Service were invited to participate in the study, regardless of smoking status or history of known COPD/asthma. Individuals underwent spirometric testing both before and after use of a salbutamol bronchodilator. Airflow obstruction was defined as forced expiratory volume in 1 s (FEV1 )/forced vital capacity (FVC) < 0.7 post-bronchodilation, whereas COPD was defined as FEV1 /FVC < 0.7 post-bronchodilation and Medical Research Council (MRC) score > 2. Multivariate logistic regression was used to evaluate risk factors associated with airflow obstruction, reported as adjusted odds ratios (aORs). RESULTS: Five hundred and three participants successfully completed spirometry testing. The median (Q1; Q3) age was 52 (44; 58) years. The median (Q1; Q3) CD4 count was 598 (438; 784) cells/µL and the median (Q1; Q3) nadir CD4 count was 224 (121; 351) cells/µL. There were 119 (24%) current smokers and 145 (29%) former smokers. Among those screened, 54 (11%) had airflow obstruction whereas three (1%) of the participants had COPD. Factors that were associated with airflow obstruction included a history of smoking [aOR 2.2; 95% confidence interval (CI) 1.1; 4.7], older age (aOR 1.6; 95% CI 1.2; 2.2), and lower CD4 count (aOR 0.8; 95% CI 0.7; 1.0). CONCLUSIONS: Airflow obstruction was relatively uncommon. Our findings suggest that PLWHIV who are ≥50 years old, smokers and those with nadir CD4 counts ≤ 200 cells/µL could be targeted to undergo spirometry to diagnose chronic airflow obstruction.

Selective Lesioning of Nuclear Factor-κB Activated Cells in the Nucleus Accumbens Shell Attenuates Alcohol Place Preference.

Nuclear factor κ-light chain enhancer of activated B cells (NF-κB) is a transcription factor commonly associated with innate immunity and is activated by infection and inflammation. NF-κB has recently gained attention as a mediator of complex psychiatric phenomena such as stress and addiction. In regards to alcohol, most research on NF-κB has focused on neurotoxicity and few studies have explored the role of NF-κB in alcohol reward, reinforcement, or consumption. In these studies, we used conditioned place preference to assess the activity of NF-κB in response to rewarding doses of alcohol. To measure NF-κB activity we used a line of transgenic mice that express the LacZ gene under the control of an NF-κB-regulated promoter. In these animals, staining for ß-galactosidase (ß-gal) identifies cells in which NF-κB has been activated. We then used the Daun02 inactivation method to specifically silence NF-κB-expressing cells during place preference conditioning. Daun02 is an inactive prodrug that is converted to the inhibitory molecule daunorubicin by ß-gal. After alcohol place conditioning, we observed increased ß-gal staining in the nucleus accumbens (NAC) shell and dorsal raphe nucleus, and found that disruption of NF-κB-expressing cells using Daun02 attenuated the development of alcohol place preference when infused into the NAC shell following conditioning sessions. We found this effect to be regionally and temporally specific. These results suggest that, in addition to its role in alcohol-induced neurotoxicity, NF-κB mediates the development of alcohol place preference via its actions in the NAC shell.

Implementing a declination form programme to improve influenza vaccine uptake by staff in Department of Veterans Affairs spinal cord injury centres: a pilot study.

BACKGROUND: Individuals with spinal cord injuries and disorders are at high risk for respiratory and influenza-related complications after developing influenza. These individuals often have frequent contact with the healthcare system. Vaccination rates in healthcare workers at Department of Veterans Affairs (VA) spinal cord injury (SCI) centres have been approximately 50% for several years. Efforts are needed to increase vaccination uptake among SCI HCWs. Declination form programmes (DFPs) in combination with other strategies have resulted in significant increases in influenza vaccination uptake in HCWs. AIM: Use of external and internal facilitation including local teams and consensus processes to pilot a DFP in two VA SCI centres and evaluate factors influencing implementation. METHODS: Implementation meetings and a consensus-building process with leadership and implementation team members were conducted, along with semi-structured post-implementation interviews with members of each implementation team (N = 7). FINDINGS: The DFP was well accepted and easy to use. Leadership was a key facilitator for DFP implementation. Barriers included difficulty communicating with HCWs working during early/late shifts. Participation was 100% at Site 1 and 48% at Site 2. CONCLUSION: Use of local teams and consensus to identify strategies to implement a DFP is feasible and effective for achieving moderate-to-high levels of participation in the programme.

Hypertension and antihypertensive treatment in veterans with spinal cord injury and disorders.

OBJECTIVES: Hypertension (HTN) is an important risk factor for cardiovascular disease, a major cause of morbidity and mortality among people with spinal cord injury and disorders (SCI/D). Our study examined prevalence, associated factors, and pharmacological treatment of HTN in Veterans with SCI/D compared with a matched control group. METHODS: A retrospective review was conducted of Veterans with traumatic SCI/D (TSCI/D; n=6672), non-traumatic SCI/D (NTSCI/D; n=3566) and a matched, non-injured cohort. RESULTS: Over half of patients with TSCI/D (56.6%) had HTN, compared with 68.4% of matched controls (P<0.001). Paraplegic and tetraplegic Veterans with TSCI/D had significantly lower odds of having a HTN diagnosis compared with control (odds ratios (OR)=0.84 (0.77-0.91); OR=0.38 (0.35-0.42)). About 71.8% of patients with NTSCI/D had HTN compared with 72.3% of matched controls (P>0.05). Paraplegic and tetraplegic Veterans with NTSCI/D did not have significantly different odds of a HTN diagnosis compared with control (OR=0.92 (0.79-1.05); OR=0.85 (0.71-1.01)). Adjusted analysis indicates that Veterans with tetraplegia and HTN were less likely to receive antihypertensive therapy (TSCI/D, OR=0.62 (0.53-0.71); NTSCI/D, OR=0.81 (0.66-0.99)). CONCLUSION: HTN appears to be more prevalent in SCI/D Veterans than previously reported. TSCI/D Veterans have a significantly lower prevalence of HTN whereas NTSCI/D Veterans have a comparable prevalence of HTN to those without SCI/D. The level of injury (tetraplegia vs paraplegia) has a large impact on the prevalence of HTN in the traumatic cohort. Subsequent antihypertensive therapy is used less in both TSCI/D and NTSCI/D Veterans with tetraplegia and more in TSCI/D Veterans with paraplegia.

Effect of HPMC on the quality of wheat-free bread made from carob germ flour-starch mixtures.

UNLABELLED: Carob germ proteins have been shown to have functional properties similar to wheat gluten enabling formulation and production of yeast leavened gluten-free baked goods from a true dough rather than a stiff batter. The purpose of this research was to optimize the production of wheat-free bread containing carob germ flour, corn starch, NaCl, sucrose, hydroxypropyl methylcellulose (HPMC), and H2O. A key criterion was to formulate viscoelastic dough similar to wheat dough. To that end, response surface methodology (RSM) was used to determine optimal levels of carob germ flour, H2O, and HPMC. Components varied as follows: 4.94%-15.05% for carob germ flour, 0.05%-3.75% HPMC, and 65.25%-83.75% H2O (percents are on a flour basis, where carob germ flour in combination with maize starch equals 100%). Sucrose, NaCl, and yeast were held constant at 2%. Bread parameters evaluated were specific volume and crumb hardness, where the largest specific volume and the lowest value for crumb hardness were considered most desirable. The optimum formula as determined by RSM consisted of 7% carob germ flour, 93% maize starch, 2% HPMC, and 80% H2O with predicted crumb hardness of ~200 g of force and a specific volume of ~3.5 cm³/g. When proof time was optimized, a specific volume of ~5.6 ml/g and crumb hardness value of ~156 g of force was observed. Carob germ flour may be used as an alternative to wheat flour in formulating viscoelastic dough and high quality gluten-free bread. PRACTICAL APPLICATION: Celiac disease affects approximately 1% of the world's population. Sufferers of the disease must consume a gluten-free diet. Currently, gluten-free baked products are made from batters and lack the ability to be made from dough based systems which limits the overall processability and product variety. This research is aimed at the utilization of carob germ protein and its ability to form dough to produce an optimal gluten-free bread formulation. This will help to alleviate problems in processability and product variety associated with gluten-free baked goods.

Health-related quality of life for veterans with spinal cord injury.

STUDY DESIGN: Cross-sectional. OBJECTIVES: The objective of this study was to examine the association between the characteristics of individuals with spinal cord injury (SCI) and self-reported health-related quality of life (HRQoL). SETTING: The United States. METHODS: Questions from the Behavioral Risk Factor Surveillance System (BRFSS) survey were sent to veterans with SCI. The analyses included 2302 respondents. Logistic regression analysis was used to examine the association between subject characteristics and the following four measures of HRQoL: frequent physical distress (FPD), frequent mental distress (FMD), frequent depressive symptoms (FDS) and poor or fair self-reported health. RESULTS: Approximately 19% of the respondents reported FMD, 27% reported FPD, 17% reported FDS and 29% reported poor or fair health. Veterans who self-reported chronic illnesses, had higher odds of reporting FPD, FMD, FDS and poor or fair health than veterans who did not report chronic illnesses. Smoking was significantly associated with decreased HRQoL. Older veterans had higher odds of reporting poor or fair health and FPD than younger veterans. Higher levels of education were associated with lower odds of FMD, FDS and poor or fair health. CONCLUSIONS: Chronic illnesses and smoking have a substantial effect on HRQoL for persons with SCI, suggesting the importance of continued efforts to improve smoking cessation methods and to treat and prevent chronic conditions.

Subintimal angioplasty for superficial femoral artery occlusion: poor patency in critical ischaemia.

INTRODUCTION: Subintimal angioplasty has been proposed for the treatment of long segment occlusive disease and for patients with critical limb ischaemia (CLI) with significant co-morbidity. There is no consensus as to short- and long-term patency. We present our experience with this technique. METHODS: Between 1995 and 2000, 43 consecutive patients (48 limbs) underwent subintimal angioplasty for superficial femoral artery occlusions. Outcome measures were haemodynamic and/or symptomatic patency. RESULTS: Technical success was achieved in 14/17 limbs with CLI (82%) and 30/31 (97%) with intermittent claudication (IC). There were 7 complications (15%), 6 occurring in the claudicant group. The median occlusion length was 10 cm for CLI and 6 cm for IC. Patency at 12 and 36 months, on an intention-to-treat basis, was 69% and 58% for claudicants and 25% and 25% for patients with CLI (P = 0.0005 and P = 0.0044, respectively). Following only technically successful procedures, 12-month patency was 72% (IC) and 31% (CLI) (P = 0.009). Patients with occlusions > or = 10 cm were more likely to re-occlude than those < 10 cm (12-month patency 60% versus 25%;P = 0.037). CONCLUSIONS: In this series, short- and long-term patency in patients with CLI is poor. Subintimal angioplasty in the treatment of CLI should be reserved for those patients not fit for surgical bypass.

Interactions between selenium and sulphur nutrition in Arabidopsis thaliana.

Selenium (Se) is an essential plant micronutrient, but is toxic at high tissue concentrations. It is chemically similar to sulphur (S), an essential plant macronutrient. The interactions between Se and S nutrition were investigated in the model plant Arabidopsis thaliana (L.) Heynh. Arabidopsis plants were grown on agar containing a complete mineral complement and various concentrations of selenate and sulphate. The Se/S concentration ratio in the shoot ([Se](shoot)/[S](shoot)) showed a complex dependence on the ratio of selenate to sulphate concentration in the agar ([Se](agar)/[S](agar)). Increasing [S](agar) increased shoot fresh weight (FW) and [S](shoot), but decreased [Se](shoot). Increasing [Se](agar) increased both [Se](shoot) and [S](shoot), but reduced shoot FW. The reduction in shoot FW in the presence of Se was linearly related to the shoot Se/S concentration ratio. These data suggest (i) that Se and S enter Arabidopsis through multiple transport pathways with contrasting sulphate/selenate selectivities, whose activities vary between plants of contrasting nutritional status, (ii) that rhizosphere sulphate inhibits selenate uptake, (iii) that rhizosphere selenate promotes sulphate uptake, possibly by preventing the reduction in the abundance and/or activity of sulphate transporters by sulphate and/or its metabolites, and (iv) that Se toxicity occurs because Se and S compete for a biochemical process, such as assimilation into amino acids of essential proteins.

Primary reversed gastric tube reconstruction in long gap esophageal atresia.

BACKGROUND/PURPOSE: Esophageal reconstruction in long-gap esophageal atresia (EA) poses a technical challenge with several surgical options. The purpose of this study was to review the authors' experience with the reversed gastric tube (RGT) in esophageal reconstruction. METHODS: This series describes 7 babies with pure EA treated at 2 centers between 1989 and 2001. Data, gathered by retrospective chart review, included clinical details of the esophageal and associated malformations, technique and timing of repair, early and late complications, and long-term follow-up. Institutional review board (IRB) approval of this study has been obtained. RESULTS: Seven babies were included. Associated malformations were present in 4: trisomy 21 in 2 and imperforate anus in 2. After gastrostomy tube placement, patients were treated with gastrostomy tube feedings and continuous upper pouch suction. Median gap length was 5.5 vertebral segments (range, 3 to 9). RGT with a posterior mediastinal esophagogastric anastomosis was performed at median age of 62 days (range, 38 to 131). There were no anastomotic leaks. Three patients had strictures, one required resection. Exclusive oral nourishment was achieved in 5 patients by 6 months of age. At last follow-up (mean, 4.5 years), 6 patients were receiving oral nutrition exclusively, and all were maintaining growth curves. CONCLUSIONS: In long gap EA, early esophageal reconstruction using an RGT can be performed with minimal morbidity and promising short-term results.

Oral folate reduces plasma homocyst(e)ine levels in hemodialysis patients with cardiovascular disease.

INTRODUCTION: Hyperhomocyst(e)inemia (plasma homocyst(e)ine concentration >16.0 micromol/l) is an independent risk factor for atherosclerosis, and is ubiquitous in patients with end-stage renal disease (ESRD). Oral folate supplementation in the non-ESRD population has been demonstrated to reduce plasma homocyst(e)ine (Hcy) concentration, and may reduce atherosclerotic morbidity. This study was undertaken to evaluate the efficacy of folate supplementation in reducing Hcy in patients with ESRD and cardiovascular disease. METHODS: Twenty-eight chronic hemodialysis patients with demonstrated hyperhomocyst(e)inemia (mean Hcy 35.2+/-13.3 micromol/l) were enrolled in the study. The presence of atherosclerosis was documented by history, physical examination, or ultrasonographic criteria. Hcy was determined initially and following six weeks' supplementation with 5.0mg folate and multvitamins. RESULTS: Hcy fell a mean of 15.0+/-10.4 micromol/l (38.9+/-19.9%) following supplementation (p<0.0005, paired t-test). In patients whose Hcy 'normalized' (n=10) Hcy fell a mean of 51+/-14% compared to a reduction of 32+/-20% in 18 patients whose Hcy remained >16.0 micromol/l (p=0.02). A significant positive correlation was observed between initial Hcy and both absolute and percent reduction after folate supplementation (r=0.87, p<0.005 and 0.53, p<0.005, respectively). Seven patients with documented atherosclerosis were older (68+/-8 yr vs 51+/-5 yr, p=0.007) an tended to have lower initial and final Hcy than the 21 patients without atherosclerosis (26.8+/-9.9 vs. 38.0+/-13.3 micromol/l, p=0.051 and 16.5+/-5.0 vs. 21.3+/-6.7, p=0.06, respectively). The presence of atherosclerosis was not associated with significant alteration in the response to folate. CONCLUSIONS: Supplementation with high-dose folate significantly reduces plasma Hcy in patients with and without atherosclerosis, and the presence of atherosclerosis does not impact on patients' response to folate and multivitamin supplementation. Hcy remained >16.0 micromol/l in the majority of patients, however, despite large absolute reductions in Hcy. Doses of folate greater than 5mg, or additional therapy may be required to further reduce Hcy in the majority of ESRD patients.

Salvage laparotomy for failure of peritoneal drainage in necrotizing enterocolitis in infants with extremely low birth weight.

BACKGROUND/PURPOSE: Peritoneal drainage is a temporizing procedure for infants with extremely low birth weight (ELBW) who have perforated necrotizing enterocolitis (NEC). "Salvage" laparotomy is advocated when patients worsen after drainage. Some patients have survived with intact gastrointestinal functional after drainage alone. The purpose of this study is to determine if these salvage laparotomies are beneficial. METHODS: The authors reviewed the records of ELBW infants treated at Stanford University with perforated NEC from 1993 through 1998. Data collected included demographic makeup, type of operation, survival rate, postoperative complications, length of stay (LOS), and cost. RESULTS: The authors treated 26 patients, 9 with laparotomy and 17 with peritoneal drainage. The peritoneal drainage group had lower birth weight and more comorbid conditions. Survival rate was similar between laparotomy and drainage: 55.6% versus 41.2%. Four patients in the drainage group underwent salvage laparotomy for perceived clinical deterioration. All of these patients died. The clinical status of patients who had salvage laparotomy and died was similar to those who did not and lived. Seven of 13 patients treated with drainage followed only by supportive care and antibiotics survived. Cost and LOS for patients undergoing salvage laparotomy were much greater than for nonsurviving patients undergoing only peritoneal drainage: 84 +/- 20 days and $660,000 compared with 34 +/- 11 days and $306,000. CONCLUSIONS: Both primary peritoneal drainage and laparotomy should be considered primary therapy for perforated NEC. Patients undergoing peritoneal drainage typically experience clinical deterioration after operation. In this limited experience, salvage laparotomy did not appear beneficial.

Response of circulating tumor cells to systemic therapy in patients with metastatic breast cancer: comparison of quantitative polymerase chain reaction and immunocytochemical techniques.

PURPOSE: We previously developed a quantitative system for the detection of cytokeratin 19 (CK-19) transcripts using reverse transcriptase polymerase chain reaction (PCR) to detect breast carcinoma cells in blood and bone marrow. The aim of this study was to determine the value of this system in monitoring patients with metastatic disease and to compare it with an established immunocytochemical method. PATIENTS AND METHODS: Patients with progressive, locally advanced, and metastatic breast cancer (all stage IV) who were due to start systemic treatment were recruited. Blood samples were analyzed for CK-19 transcripts using quantitative PCR (QPCR) and immunocytochemistry (ICC) throughout their course of treatment. RESULTS: One hundred forty-five blood samples were obtained from 22 patients over 13 months. Seventy-two (49.6%) of these samples were positive by QPCR, and 56 (42%) of 133 were positive by ICC. Of the 133 specimens analyzed by both techniques, 95 (71.4%) had the same results for each, and of the 71 samples that were positive, 40 (56%) were positive by both methods. The relationship between the number of cells detected and the QPCR values was statistically significant (P <.0001). Of the 25 courses of assessable treatment, 17 (68%) of 25 treatment outcomes (either response or disease progression) were reflected by QPCR measurements, and 12 (57%) of 21 were reflected by ICC. During the course of the study, five patients showed a response, and of these, ICC was in agreement in four cases (80%) and QPCR in three cases (60%). Eighteen courses of treatment resulted in progression of the disease; however, only 15 of these were assessable by ICC. ICC was in agreement in eight (53%) of 15 of these cases, and QPCR in 15 (83%) of 18 cases. CONCLUSION: Circulating carcinoma cells are frequently found in patients with metastatic breast cancer. In the majority of patients, cancer cell numbers as evaluated by QPCR or ICC reflected the outcome of systemic treatment.

Microsatellite alterations plasma DNA of primary breast cancer patients.

The aim of this study was to analyze plasma DNA from primary and metastatic breast cancer cases for tumor-specific alterations and to compare these findings with immunocytochemistry and estimation of cytokeratin 19 (CK19) mRNA for detection of micrometastases. DNA was extracted from plasma, lymphocytes, and microdissected tumor tissue sections obtained from 71 patients with breast cancer and 9 controls. DNA samples were analyzed for loss of heterozygosity (LOH) and/or microsatellite instability (MI) by PCR with two polymorphic markers (DM-1 and D16S400). Reverse transcription-quantitative PCR (QPCR) and immunocytochemistry were used for detection of CK19 mRNA and protein. Breast cancer plasma DNA displayed frequent LOH (31.3%) and MI (11.6%) supported by the same alteration in microdissected tumor DNA. Most notably, 10 of the 39 patients with primary breast cancer showed LOH (n = 6) or MI (n = 4). We compared plasma tumor DNA, plasma and bone marrow QPCR, and blood and bone marrow immunocytochemistry in 32 of the patients with primary cancer. Of these, only one patient had immunocytochemically detectable carcinoma cells in the blood, and three showed abnormally high levels of plasma CK19 mRNA. All four of these patients had plasma DNA alterations. We then compared bone marrow findings: of the 10 primary breast cancers that showed LOH or MI, 6 had elevated CK19 mRNA and 5 had immunocytochemically positive cells. Tumor DNA is readily detectable in plasma of primary and metastatic breast cancer patients, and plasma DNA alterations (LOH and MI) reflect those seen in the tumor. The application of microsatellite analyses to plasma DNA may be useful in assessing tumor burden in breast cancer patients, particularly when combined with QPCR, and is preferable for patients with breast cancer, for whom sequential bone marrow aspiration is undesirable.

Cardiovascular and renal benefits of dry bean and soybean intake.

Dry beans and soybeans are nutrient-dense, fiber-rich, and are high-quality sources of protein. Protective and therapeutic effects of both dry bean and soybean intake have been documented. Studies show that dry bean intake has the potential to decrease serum cholesterol concentrations, improve many aspects of the diabetic state, and provide metabolic benefits that aid in weight control. Soybeans are a unique source of the isoflavones genistein and diadzein, which have numerous biological functions. Soybeans and soyfoods potentially have multifaceted health-promoting effects, including cholesterol reduction, improved vascular health, preserved bone mineral density, and reduction of menopausal symptoms. Soy appears to have salutary effects on renal function, although these effects are not well understood. Whereas populations consuming high intakes of soy have lower prevalences of certain cancers, definitive experimental data are insufficient to clarify a protective role of soy. The availability of legume products and resources is increasing, incorporating dry beans and soyfoods into the diet can be practical and enjoyable. With the shift toward a more plant-based diet, dry beans and soy will be potent tools in the treatment and prevention of chronic disease.

Quantitative polymerase chain reaction for the detection of micrometastases in patients with breast cancer.

PURPOSE: Previous reports have indicated that reverse transcriptase polymerase chain reaction (RT-PCR) for cytokeratin 19 (CK-19) may be useful in the management of patients with breast cancer. However, the specificity of this technique is low, principally because of a high rate of false-positive results. To improve the specificity of this assay, we developed a quantitative RT-PCR methodology that enables an estimate to be made of the number of CK-19 transcripts in blood and bone marrow samples. PATIENTS AND METHODS: We examined 45 peripheral-blood samples and 30 bone marrow samples from patients with a variety of nonneoplastic conditions using nested RT-PCR for CK-19. We also examined bone marrow and peripheral-blood samples from 23 patients with primary breast cancer and peripheral-blood samples from 37 patients with metastatic breast cancer. The number of CK-19 transcripts was estimated in positive specimens by competitive PCR and normalized to the number of ABL transcripts as an internal control for the quality and quantity of cDNA. RT-PCR results were compared with the numbers of CK-19-positive cells detected by immunocytochemistry. RESULTS: Analysis of samples from patients without cancer enabled us to define an upper limit for the background ratio of CK-19 to ABL transcripts (1:1,000 for blood samples and 1:1,600 for bone marrow samples). Using these figures as cut-off points, elevated CK-19: ABL ratios were detected in peripheral-blood samples of 20 of 37 (54%) patients with metastatic breast cancer and in bone marrow samples of 14 of 23 (61%) patients with primary breast cancer. Only three of 23 (13%) primary breast cancer peripheral-blood samples and none of the control samples were positive by these criteria. Only two of 23 patients (9%) with primary breast cancer showed immunocytochemically detectable cells in the blood; 10 of 23 (43%) showed immunocytochemically detectable cells in the bone marrow. Of 36 patients with metastatic breast cancer, eight (22%) showed positive events. CONCLUSION: Quantitative RT-PCR for CK-19 detects a percentage of patients with breast cancer and may enable the progression or regression of the disease to be monitored.

Standardization of the immunocytochemical detection of cancer cells in BM and blood: I. establishment of objective criteria for the evaluation of immunostained cells.

BACKGROUND: Detection of isolated tumor cells (TC) in BM from carcinoma patients can predict future relapse. Various molecular and immunocytochemical (ICC) methods have been used to detect these cells, which are present at extremely low frequencies of 10(-5) - 10(-6). The specificity and sensitivity of these techniques may vary widely. In 1996, a European ISHAGE Working Group was founded to standardize and optimize procedures used for the detection of minimal residual disease. We have attempted to develop objective criteria for the evaluation of immunocytochemically identifiable cancer cells. METHODS: An interlaboratory ring experiment was performed, to compare the screening and detection of micrometastasis-positive events between different laboratories. The discrepant results induced us to establish a common consensus on morphological criteria applicable to the identification of immunostained micrometastatic TC. RESULTS: Bared on this consensus evaluation, we propose a classification of stained elements into three groups: (1) 'TC's show pathognomonic signs of epithelial TC-nature, as defined by a clearly enlarged nucleus or clusters of > or = 2 immunopositive cells. (2) 'Probable TC's represent morphological overlap between hematopoietic cells (HC) and TC which lack pathognomonic signs of TC-nature, but do not exhibit clear morphological features of HC. These cells are considered as TC if control staining with an isotype-specific, unrelated Ab is negative. (3) 'TC-negative' cells are defined as 'false positive' HC, skin squamous epithelial cells and artefacts. DISCUSSION: The proposed classification of immunostained events is a first step towards the development of standardized immunocytochemical assays for the detection of occult micrometastatic TC in BM or blood.