Potential of mid-infrared spectroscopy to aid the triage of patients with acute chest pain.

A total of 1,429 serum samples from 389 consecutive patients with acute chest pain were analyzed with the goal to aid the rapid diagnosis of acute myocardial infarction. To the best of our knowledge this is the largest and most comprehensive study on mid-infrared spectroscopy in cardiology. We were able to identify those signatures in the mid-infrared spectra of the samples, which were specific to either acute myocardial infarction or chest pain of other origin (angina pectoris, oesophagitis, etc). These characteristic spectral differences were used to distinguish between the cause of the donor's acute chest pain using robust linear discriminant analysis. A sensitivity of 88.5% and a specificity of 85.1% were achieved in a blind validation. The area under the receiver operating characteristics curve amounts to 0.921, which is comparable to the performance of routine cardiac laboratory markers within the same study population. The biochemical interpretation of the spectral signatures points towards an important role of carbohydrates and potentially glycation. Our studies indicate that the "Diagnostic Pattern Recognition (DPR)" method presented here has the potential to aid the diagnostic procedure as early as within the first 6 hours after the onset of chest pain.

Microvessel density >or=60 does not predict for outcome after radiation treatment for locally advanced head and neck squamous cell carcinoma: results of a correlative study from the Radiation Therapy Oncology Group (RTOG) 90-03 Trial.

OBJECTIVES: To assess whether microvessel density (MVD), an immunohistochemical marker for tumor vascularity, predicts for radiotherapy (RT) outcome in locally advanced HNSCC patients. METHODS: A total of 459 patients, enrolled on the RTOG 90-03 trial, had biopsy specimens submitted, and a value for MVD determined, prior to definitive RT. 450 patients were analyzable for this study. Tumor microvessels were stained for factor VIII-related antigen using a standard immunoperoxidase method. The mean number of stained microvessel profiles, from three x200 fields containing the highest MVD (hot spot), was recorded as the MVD. A prospective value of >or=60 was chosen as the threshold for high MVD, tumor vascularity. RESULTS: The median follow-up for the analyzable patients with MVD assessment was 22.0 months and 79.1 months for all living patients. There were no differences concerning the pretreatment characteristics between those RTOG 90-03 patients with a value for MVD and those without a value for MVD. Thus, the present study cohort possessed comparable characteristics with the entire RTOG 90-03 population. MVD values ranged from 5 to 80, with a median value of 30. Only 37 of 450 (8.2%) patients possessed an MVD >or=60. There were no outcome differences for patients with MVD <60 versus >or=60 on multivariate analysis for time to local-regional failure (P = 0.89), time to distant metastasis (P = 0.80), disease-free survival (P = 0.46), and overall survival (P = 0.39). CONCLUSIONS: In this large, correlative study, a MVD >or=60, ie, high tumor vascularity, did not predict for outcome in locally advanced head and neck squamous cell carcinoma patients treated with radiotherapy.

Ki-67 staining is a strong predictor of distant metastasis and mortality for men with prostate cancer treated with radiotherapy plus androgen deprivation: Radiation Therapy Oncology Group Trial 92-02.

PURPOSE: The Ki-67 staining index (Ki67-SI) has been associated with prostate cancer patient outcome; however, few studies have involved radiotherapy (RT) -treated patients. The association of Ki67-SI to local failure (LF), biochemical failure (BF), distant metastasis (DM), cause-specific death (CSD) and overall death (OD) was determined in men randomly assigned to short term androgen deprivation (STAD) + RT or long-term androgen deprivation (LTAD) + RT. PATIENTS AND METHODS: There were 537 patients (35.5%) on Radiation Therapy Oncology Group (RTOG) 92-02 who had sufficient tissue for Ki67-SI analysis. Median follow-up was 96.3 months. Ki67-SI cut points of 3.5% and 7.1% were previously found to be related to patient outcome and were examined here in a Cox proportional hazards multivariate analysis (MVA). Ki67-SI was also tested as a continuous variable. Covariates were dichotomized in accordance with stratification and randomization criteria. RESULTS: Median Ki67-SI was 6.5% (range, 0% to 58.2%). There was no difference in the distribution of patients in the Ki-67 analysis cohort (n = 537) and the other patients in RTOG 92-02 (n = 977) by any of the covariates or end points tested. In MVAs, Ki67-SI (continuous) was associated with LF (P =.08), BF (P =.0445), DM (P <.0001), CSD (P <.0001), and OD (P =.0094). When categoric variables were used in MVAs, the 3.5% Ki67-SI cut point was not significant. The 7.1% cut point was related to BF (P =.09), DM (P =.0008), and CSD (P =.017). Ki67-SI was the most significant correlate of DM and CSD. A detailed analysis of the hazard rates for DM in all possible covariate combinations revealed subgroups of patients treated with STAD + RT that did not require LTAD. CONCLUSION: Ki67-SI was the most significant determinant of DM and CSD and was also associated with OD. The Ki67-SI should be considered for the stratification of patients in future trials.

Lack of prognostic significance of p53 and K-ras mutations in primary resected non-small-cell lung cancer on E4592: a Laboratory Ancillary Study on an Eastern Cooperative Oncology Group Prospective Randomized Trial of Postoperative Adjuvant Therapy.

PURPOSE: To determine the prognostic and predictive significance of p53 and K-ras mutations in patients with completely resected non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients were randomized preoperatively to receive adjuvant postoperative radiotherapy (Arm A) or radiotherapy plus concurrent chemotherapy (Arm B). p53 protein expression was studied by immunohistochemistry (IHC) and p53 mutations in exons 5 to 8 were evaluated by single-strand conformational analysis. K-ras mutations in codons 12, 13, and 61 were determined using engineered restriction fragment length polymorphisms. RESULTS: Four hundred eighty-eight patients were entered onto E3590; 197 tumors were assessable for analysis. Neither presence nor absence of p53 mutations, p53 protein expression, or K-ras mutations correlated with survival or progression-free survival. There was a trend toward improved survival for patients with wildtype K-ras (median, 42 months) compared with survival of patients with mutant K-ras who were randomized to chemotherapy plus radiotherapy (median, 25 months; P = .09). Multivariate analysis revealed only age and tumor stage to be significant prognostic factors, although there was a trend bordering on statistical significance for K-ras (P = .066). Analysis of survival difference by p53 by single-stranded conformational polymorphism and IHC, interaction of p53 and K-ras, interaction of p53 and treatment arm, nodal station, extent of surgery, weight loss, and histology did not reach statistical significance. CONCLUSION: p53 mutations and protein overexpression are not significant prognostic or predictive factors in resected stage II or IIIA NSCLC. K-ras mutations may be a weak prognostic marker. p53 or K-ras should not be routinely used in the clinical management of these patients.

College of American Pathologists Conference XXXV: solid tumor prognostic factors-which, how and so what? Summary document and recommendations for implementation. Cancer Committee and Conference Participants.

The College of American Pathologists convened a prognostic factor conference in June 1999 to consider prognostic and predictive factors in breast, colon, and prostate cancer, and to stratify these factors into categories reflecting the strength of published evidence. Because so little progress in prognostic factor clinical utility has been made in the last 5 years, the conference participants focused their attention on decreasing variation in methods, interpretation, and reporting of these factors so that greater clarity of value could be achieved. The conference was organized to promote discussion, broad input, and future planning. An initial plenary session provided an overview of the status of tumor marker research, the impact of variation in medicine and pathology, and statistical issues related to prognostic factor research. In working group sessions for each cancer type, participants interactively evaluated and refined the documents created by the expert panels. A second plenary session dealt with issues common to all 3 groups, including the problem of micrometastases in lymph nodes in these sites; statistical issues that arose during the breakout discussions; and issues of variation in methods, interpretation, and reporting of immunohistochemical assays. A faculty session brainstormed strategies that could be used to implement the changes recommended. This session included invited representatives of the Food and Drug Administration, Health Care Financing Administration, Centers for Disease Control and Prevention, National Cancer Institute, American Joint Committee on Cancer, and International Union Against Cancer. Cancer site and general recommendations were presented and discussed during a final session to achieve consensus of the conference participants and to address feasibility of implementation of these recommendations. A final discussion focused on future initiatives that might lead to implementation of the changes proposed in the conference by the various organizations represented. This report summarizes the general conference recommendations, cancer working group recommendations, and plans for implementation of the recommendations.

Prognostic factors in colorectal cancer. College of American Pathologists Consensus Statement 1999.

BACKGROUND: Under the auspices of the College of American Pathologists, the current state of knowledge regarding pathologic prognostic factors (factors linked to outcome) and predictive factors (factors predicting response to therapy) in colorectal carcinoma was evaluated. A multidisciplinary group of clinical (including the disciplines of medical oncology, surgical oncology, and radiation oncology), pathologic, and statistical experts in colorectal cancer reviewed all relevant medical literature and stratified the reported prognostic factors into categories that reflected the strength of the published evidence demonstrating their prognostic value. Accordingly, the following categories of prognostic factors were defined. Category I includes factors definitively proven to be of prognostic import based on evidence from multiple statistically robust published trials and generally used in patient management. Category IIA includes factors extensively studied biologically and/or clinically and repeatedly shown to have prognostic value for outcome and/or predictive value for therapy that is of sufficient import to be included in the pathology report but that remains to be validated in statistically robust studies. Category IIB includes factors shown to be promising in multiple studies but lacking sufficient data for inclusion in category I or IIA. Category III includes factors not yet sufficiently studied to determine their prognostic value. Category IV includes factors well studied and shown to have no prognostic significance. MATERIALS AND METHODS: The medical literature was critically reviewed, and the analysis revealed specific points of variability in approach that prevented direct comparisons among published studies and compromised the quality of the collective data. Categories of variability recognized included the following: (1) methods of analysis, (2) interpretation of findings, (3) reporting of data, and (4) statistical evaluation. Additional points of variability within these categories were defined from the collective experience of the group. Reasons for the assignment of an individual prognostic factor to category I, II, III, or IV (categories defined by the level of scientific validation) were outlined with reference to the specific types of variability associated with the supportive data. For each factor and category of variability related to that factor, detailed recommendations for improvement were made. The recommendations were based on the following aims: (1) to increase the uniformity and completeness of pathologic evaluation of tumor specimens, (2) to enhance the quality of the data needed for definitive evaluation of the prognostic value of individual prognostic factors, and (3) ultimately, to improve patient care. RESULTS AND CONCLUSIONS: Factors that were determined to merit inclusion in category I were as follows: the local extent of tumor assessed pathologically (the pT category of the TNM staging system of the American Joint Committee on Cancer and the Union Internationale Contre le Cancer [AJCC/UICC]); regional lymph node metastasis (the pN category of the TNM staging system); blood or lymphatic vessel invasion; residual tumor following surgery with curative intent (the R classification of the AJCC/UICC staging system), especially as it relates to positive surgical margins; and preoperative elevation of carcinoembryonic antigen elevation (a factor established by laboratory medicine methods rather than anatomic pathology). Factors in category IIA included the following: tumor grade, radial margin status (for resection specimens with nonperitonealized surfaces), and residual tumor in the resection specimen following neoadjuvant therapy (the ypTNM category of the TNM staging system of the AJCC/UICC). (ABSTRACT TRUNCATED)

Prognostic factors in prostate cancer. College of American Pathologists Consensus Statement 1999.

BACKGROUND: Under the auspices of the College of American Pathologists, a multidisciplinary group of clinicians, pathologists, and statisticians considered prognostic and predictive factors in prostate cancer and stratified them into categories reflecting the strength of published evidence and taking into account the expert opinions of the Prostate Working Group members. MATERIALS AND METHODS: Factors were ranked according to the previous College of American Pathologists categorical rankings: category I, factors proven to be of prognostic importance and useful in clinical patient management; category II, factors that have been extensively studied biologically and clinically but whose importance remains to be validated in statistically robust studies; and category III, all other factors not sufficiently studied to demonstrate their prognostic value. Factors in categories I and II were considered with respect to variations in methods of analysis, interpretation of findings, reporting of data, and statistical evaluation. For each factor, detailed recommendations for improvement were made. Recommendations were based on the following aims: (1) increasing uniformity and completeness of pathologic evaluation of tumor specimens, (2) enhancing the quality of data collected pertaining to existing prognostic factors, and (3) improving patient care. RESULTS AND CONCLUSIONS: Factors ranked in category I included preoperative serum prostate-specific antigen level, TNM stage grouping, histologic grade as Gleason score, and surgical margin status. Category II factors included tumor volume, histologic type, and DNA ploidy. Factors in category III included perineural invasion, neuroendocrine differentiation, microvessel density, nuclear roundness, chromatin texture, other karyometric factors, proliferation markers, prostate-specific antigen derivatives, and other factors (oncogenes, tumor suppressor genes, apoptosis genes, etc).

The challenge of variation in medical practice.

Medicine has been identified as a profession for almost 3000 years based on a core premise that physicians have the right to evaluate their own quality. Because medicine is a profession and because of the special privileges granted to physicians by society, quality-based principles that evolved in the manufacturing business have been difficult to adapt to medical practice. Physicians learn from other physicians and medical literature. This leads to wide variation in what is considered best practice. Variation has complex association, including the variation in expert opinion, the complexity of medical knowledge, the variation in physician decision-making potential, and human error. Guidelines or algorithms are a strategy that are finding favor as a solution. The control of variation through guideline development, iterative refinement of guidelines, and feedback to physicians will improve medical practice. By removing variation, physicians can honor the fiduciary trust that they have made to patients, make reasoned decisions, improve outcomes, and focus attention on making medical improvements.

Statistical issues in tumor marker studies.

CONTEXT: Inferences from tumor marker studies are complicated by a variety of statistical concerns, which can make proper interpretation of results difficult. This article focuses on important issues that should be addressed when designing, conducting, and analyzing tumor marker studies. OBJECTIVE: To highlight the importance of considering statistical significance, risk ratios, statistical power, reproducibility, multiple testing, confirmatory studies, and missing data in the design of marker studies used for prognosis. RESULTS: Suggestions are provided for more effectively conducting marker studies. These include more careful attention to adequacy of the number of subjects for a marker study and improved documentation and standardization of assay methods. The importance of complete reporting of study results and description of the statistical analysis methods used is also emphasized. CONCLUSION: Cooperation among clinicians, laboratory scientists, and statisticians will be required to conduct statistically sound tumor marker studies and to facilitate prioritizing markers for new and confirmatory studies in an environment of limited patient and specimen resources.

Protocols for the examination of tumors of diverse sites: introduction. Cancer committee of the College of American Pathologists.

This issue of the Archives includes previously unpublished protocols for the examination of specimens removed from patients with cancer of diverse sites. We provide a historical context for the development of these protocols and describe the process of development and approval. General information about the structure and content of the protocols is also provided. Cancer protocol development is an important step in the process of standardized cancer reporting. The value of such standardized reporting is discussed.

Receptor recognition and specificity of interleukin-8 is determined by residues that cluster near a surface-accessible hydrophobic pocket.

To determine the regions of interleukin-8 (IL-8) that allow high affinity and interleukin-8 receptor type 1 (IL8R1)-specific binding of chemokines, we produced chimeric proteins containing structural domains from IL-8, which binds to both IL8R1 and interleukin-8 receptor type 2 (IL8R2) with high affinity, and from GRO gamma, which does not bind to IL8R1 and binds to IL8R2 with reduced affinity. Receptor binding activity was tested by competition of 125I-IL-8 binding to recombinant IL8R1 and IL8R2 cell lines. Substitution into IL-8 of the GRO gamma sequences corresponding to either the amino-terminal loop (amino acids 1-18) or the first beta-sheet (amino acids 18-32) reduced binding to both IL8R1 and IL8R2. The third beta-sheet of IL-8 (amino acids 46-53) was required for binding to IL8R1 but not IL8R2. Exchanges of the second beta-sheet (amino acids 32-46) or the carboxyl-terminal alpha-helix (amino acids 53-72) had no significant effect. When IL-8 sequences were substituted into GRO gamma, a single domain containing the second beta-sheet of IL-8 (amino acids 18-32) was sufficient to confer high affinity binding for both IL8R1 and IL8R2. The amino-terminal loop (amino acids 1-18) and the third beta-sheet (amino acids 46-53) of IL-8 had little effect when substituted individually but showed increased binding to both receptors when substituted in combination. Individual amino acid substitutions were made at positions where IL-8 and GRO gamma sequences differ within the regions of residues 11-21 and 46-53. IL-8 mutations L49A or L49F selectively inhibited binding to IL8R1. Mutations Y13L and F21N enhanced binding to IL8R1 with little effect on IL8R2. A combined mutation Y13L/S14Q selectively decreased binding to IL8R2. Residues Tyr13, Ser14, Phe21, and Lys49 are clustered in and around a surface-accessible hydrophobic pocket on IL-8 that is physically distant from the previously identified ELR binding sequence. A homology model of GRO gamma, constructed from the known structure of IL-8 by refinement calculations, indicated that access to the hydrophobic pocket was effectively abolished in GRO gamma. These studies suggest that the surface hydrophobic pocket and/or adjacent residues participate in IL-8 receptor recognition for both IL8R1 and IL8R2 and that the hydrophobic pocket itself may be essential for IL8R1 binding. Thus this region contains a second site for IL-8 receptor recognition that, in combination with the Glu4-Leu5-Arg6 region, can modulate receptor binding affinity and IL8R1 specificity.

IL-8 induces neutrophil chemotaxis predominantly via type I IL-8 receptors.

IL-8 is a potent proinflammatory cytokine that has a key role in the recruitment and activation of neutrophils during inflammation. IL-8 reacts with neutrophils via two distinct types of IL-8-R. Receptor-specific Abs were raised against peptides derived from the first extracellular domain of each IL-8-R. Anti-IL-8-R1 and anti-IL-8-R2 selectively block 125I-IL-8 binding to rIL-8-R type 1 or 2, respectively. The anti-peptide Abs were used to assess the role of each receptor in the chemotactic response of neutrophils to GRO alpha and to IL-8. Anti-IL-8-R2 blocks GRO alpha-induced chemotaxis of neutrophils. Chemotaxis to GRO alpha is not inhibited by anti-IL-8-R1. Thus GRO alpha stimulates chemotaxis exclusively through IL-8-R2 and independently of IL-8-R1. Surprisingly, anti-IL-8-R1 inhibits the majority (78 +/- 3%) of IL-8-induced neutrophil chemotaxis. Only a minor proportion of IL-8-induced chemotaxis (29 +/- 5%) is inhibited by anti-IL-8-R2. These findings indicate that chemotaxis to IL-8 is mediated predominantly by type 1 IL-8-Rs and suggest that IL-8-R1 is an appropriate target for therapeutic strategies to limit neutrophil influx in diseases where neutrophils contribute to pathophysiology.

Correlation between cellular rejection of cardiac allografts and quantitative changes among T-cell subsets identified by V beta epitope expression.

BACKGROUND: Cellular rejection of an allograft is mediated in part by peripheral blood T cells. We tested the hypothesis that quantitative changes in T-cell subsets can be detected in the peripheral blood and that these changes correlate with rejection. METHODS AND RESULTS: T-cell subset analysis was performed by flow cytometry using monoclonal antibodies recognizing six isotypic epitopes of the T-cell receptor beta-chain variable (V) region. These analyses were done at 7-day (mean) time intervals. Fluctuations within a given subset were determined by dividing the number of positive cells observed by the number of positive cells found on the previous analysis. For healthy volunteers observed over a period of 30 days, 119 of 120 subset ratios (99.2%) fell between 0.5 and 2.0. For patients, 57 of 240 subset ratios (23.8%) fell outside of this range (P < .004, chi 2). The occurrence of the abnormal ratios coincided more closely with cellular rejection (mean +/- SD, 7.7 +/- 6.2 days from a positive biopsy; median, 5 days; range, 0 to 28 days) than did the occurrence of normal subset ratios (mean +/- SD, 14.4 +/- 10.9 days from a positive biopsy; median, 11 days; range, 0 to 44 days; P < .005 by Mann-Whitney U test). Regression analysis confirmed a significant (P < .001, R = .91) temporal association between cellular rejection and abnormal subset fluctuations. No correlation was found between abnormal subset ratios and either vascular rejection or use of high-dose prednisone. CONCLUSIONS: T-cell subset measurement may be a method of noninvasive monitoring of cellular rejection after transplantation and may provide insights into the physiology of graft rejection with the potential for the development of more specific immunosuppressive therapy.

Accelerated rejection of murine cardiac allografts by murine cytomegalovirus-infected recipients. Lack of haplotype specificity.

Clinical studies have revealed a correlation between cytomegalovirus (CMV) infection and acute allograft rejection. Likewise, for a murine model we observed that C3H (H-2k) recipients infected with murine CMV (MCMV) rejected BALB/c (H-2d) cardiac allografts earlier than uninfected recipients (6.9 +/- 0.1 d compared with 8.1 +/- 0.6 d; P < 0.001). It has been hypothesized that MCMV epitopes crossreact with alloantigens and in this manner induce rejection. However, we also demonstrated that MCMV caused accelerated rejection in the reverse combination (C3H heart engrafted to BALB/c recipient; 7.2 +/- 0.3 and 9.4 +/- 0.4 d for infected and control animals, respectively; P < 0.001) and accelerated rejection of grafts of a third, unrelated haplotype (C57Bl/6; H-2b; 8.0 +/- 0.7 d compared with 10.1 +/- 0.6 for infected and control C3H recipients, respectively; P < 0.03). Ultraviolet (UV) inactivation of MCMV before administration to the graft recipient abrogated the ability to induce rapid rejection. Activated T lymphocytes were present in grafts from infected recipients 2 d before control recipients (P < 0.02) and, at the time of graft rejection, were almost exclusively CD8+ for both infected and control recipients. Thus, MCMV accelerated rejection appears not to result from crossreaction between MCMV epitopes and MHC products. The failure of UV-inactivated virus to accelerate rejection and the high proportion of CD8+ T cells recovered from all rejected grafts suggest that the class I pathway of antigen presentation may be important in the induction of early rejection.

Evidence for an autocrine/paracrine function of chorionic gonadotropin in Xanthomonas maltophilia.

In the human and all other mammalian systems studied, LH and hCG bind to a common high affinity receptor with equal affinity. We have recently reported that a unique high affinity binding site in Xanthomonas maltophilia preferentially binds hCG and a native CG-like ligand over LH or other glycoprotein hormones. In the current studies, we have analyzed the effect of hCG or the native ligand on culturing Xanthomonas maltophilia. Both the human and native ligand caused a dose-dependent alteration in the pattern of the growth cycle and a change in the morphology of the bacteria during the stationary phase of the growth cycle. The protein concentration reached during the stationary phase was significantly (P < 0.005) higher in cultures supplemented with hCG or the native ligand. When an aliquot of the culture was diluted and plated on Earl's Martin Balanced agar plates, the number of subsequent colonies was increased (P < 0.02) in the fractions supplemented with the ligands. The increased growth was significant (P < 0.05) to the lowest concentration of 50 ng/ml ligand. When grown under partially anaerobic conditions, the effects of hCG were observed earlier in the growth cycle. The active hormones, hCG and native ligand, also changed bacterial morphology. These data indicate that hCG may have an autocrine and/or paracrine function in bacteria.