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PubMed1994

The pathologist and the residual tumor (R) classification.

The R classification, adopted in 1987 by the UICC, denotes absence or presence of residual tumor after treatment. Residual tumor may be localized in the area of the primary tumor and/or as distant metastases. R0 corresponds to resection for cure or complete remission. R1 to microscopic residual tumor, R2 to macroscopic residual tumor. The R classification takes into account clinical and pathological findings. A reliable classification requires the pathological examination of resection margins. The R classification has considerable clinical significance, particularly being a strong predictor of prognosis. General and specific procedures for performing pathological R classification on resection specimens of different organs will be described. New methods in R classification comprise imprint cytology, cytolocial examination of ascites, examination of bone marrow biopsy. The importance of these methods will have to be established in the future.

Humans↗
PubMed2002

[New WHO classification of myelodysplastic syndromes. The consequences].

Myelodysplastic syndromes (MDS) are clonal hematopoietic disorders. Diagnosis and classification of MDS are based on morphological features of blood and bone marrow cells. The F.A.B. classification is widely used, but remains unclear in some cases of MDS. A World Health Organization (WHO) working group proposed a new classification of MDS, to improve the homogeneity of the different categories in term of physiopathology and prognosis. The new WHO classification incorporated some clinical and etiological data, and the results of cytogenetical or molecular analysis. The homologies and the differences between these two classification are showed, and the clinical consequences of the new classification are discussed.

Bone Marrow Cells↗
PubMed1999

Ductal carcinoma in situ of the breast from a population-defined cohort: an evaluation of new histopathological classification systems.

The increased incidence of ductal carcinoma in situ of the breast (DCIS) in the era of mammography screening requires a deeper knowledge of the biology of the disease and calls for a suitable classification system to optimise therapy. Our aim was to evaluate the correlation to prognosis for two new classification systems of DCIS. The histopathological specimens from 195 women consecutively diagnosed between 1986 and 1994 with a primary DCIS were re-classified by two separate observers using the system proposed by an European Organization for Research and Treatment of Cancer (EORTC) working group and the Van Nuys system. The relapse-free survival (RFS) by histopathological subgroup and by nuclear grade only was estimated for women treated with breast conserving surgery (n = 149). Thirty-two local recurrences occurred among 149 women (mean follow-up time 59 months). No distant recurrences or breast cancer deaths were reported. The women in the group with the highest differentiation according to the EORTC classification had no recurrences. RFS did not differ appreciably between the two other groups. This was true also after stratification for radiotherapy. We found no statistically significant difference in RFS between the three groups in the Van Nuys classification. There was an overall agreement between the observers in 79% and 64% of the cases, according to the EORTC and Van Nuys systems, respectively. We were able to define one group with highly differentiated lesions and an excellent prognosis with the EORTC classification. Further classification into intermediate and low differentiated lesions did not help predict RFS.

Adult↗
PubMed2003

The new World Health Organization/International Society of Urological Pathology (WHO/ISUP) classification for TA, T1 bladder tumors: is it an improvement?

The World Health Organization/International Society of Urological Pathology (WHO/ISUP) consensus classification of urothelial neoplasms of the urinary bladder was developed in an attempt to both improve upon prior classification systems as well as to adopt a classification system that would have widespread acceptance. Prior to this classification system, numerous diverse grading schemes for bladder cancer existed whereby the same lesion seen by different pathologists would result in very different diagnoses solely based on definitional differences of lesions. Another strength of the consensus classification system is that it provides detailed histological criteria for papillary urothelial lesions. In contrast, prior grading systems for bladder tumors were vague and subjective. The current classification system allows for designation of a lesion (papillary urothelial neoplasm of low malignant potential), which biologically has a very low risk of progression, yet is not entirely benign. In the past, these lesions were a source of controversy, as some experts in the field required very restrictive criteria for the diagnosis of papilloma and would label such lesions as malignant. Other experts in the field, not wanting to label a patient with such a low-grade papillary lesion as having carcinoma, would diagnose these lesions as papilloma. This intermediate category allows both schools of thought to diagnose a lesion as not fully malignant, yet still documents need for additional follow-up. Since its inception, several studies have been published documenting the relationship of tumors classified using the WHO/ISUP system to prognosis. These articles are summarized within this review.

Consensus↗
PubMed2004

Computerized detection and classification of cancer on breast ultrasound.

RATIONALE AND OBJECTIVES: To develop and evaluate a two-stage computerized method that first detects suspicious regions on ultrasound images, and subsequently distinguishes among different lesion types. MATERIALS AND METHODS: The first stage of detecting potential lesions was based on expected lesion shape and margin characteristics. After the detection stage, all candidate lesions were classified by a Bayesian neural net based on computer-extracted lesion features. Two separate tasks were performed and evaluated at the classification stage: the first classification task was the distinction between all actual lesions and false-positive detections; the second classification task was the distinction between actual cancer and all other detected lesion candidates (including false-positive detections). The neural nets were trained on a database of 400 cases (757 images), consisting of complex cysts and benign and malignant lesions, and tested on an independent database of 458 cases (1,740 images including 578 normal images). RESULTS: In the distinction between all actual lesions and false-positive detections, Az values of 0.94 and 0.91 were obtained with the training and testing data sets, respectively. Sensitivity by patient of 90% at 0.45 false-positive detections per image was achieved for this detection-plus-classification scheme for the testing data set. Distinguishing cancer from all other detections (false-positives plus all benign lesions) proved to be more challenging, and Az values of 0.87 and 0.81 were obtained during training and testing, respectively. Sensitivity by patient of 100% at 0.43 false-positive malignancies per image was achieved in the detection and classification of cancerous lesions for the testing dataset. CONCLUSION: The results show promising performance of the computerized lesion detection and classification method, and indicate the potential of such a system for clinical breast ultrasound.

Breast Neoplasms↗
PubMed2000

Adaptive, template moderated, spatially varying statistical classification.

A novel image segmentation algorithm was developed to allow the automatic segmentation of both normal and abnormal anatomy from medical images. The new algorithm is a form of spatially varying statistical classification, in which an explicit anatomical template is used to moderate the segmentation obtained by statistical classification. The algorithm consists of an iterated sequence of spatially varying classification and nonlinear registration, which forms an adaptive, template moderated (ATM), spatially varying statistical classification (SVC). Classification methods and nonlinear registration methods are often complementary, both in the tasks where they succeed and in the tasks where they fail. By integrating these approaches the new algorithm avoids many of the disadvantages of each approach alone while exploiting the combination. The ATM SVC algorithm was applied to several segmentation problems, involving different image contrast mechanisms and different locations in the body. Segmentation and validation experiments were carried out for problems involving the quantification of normal anatomy (MRI of brains of neonates) and pathology of various types (MRI of patients with multiple sclerosis, MRI of patients with brain tumors, MRI of patients with damaged knee cartilage). In each case, the ATM SVC algorithm provided a better segmentation than statistical classification or elastic matching alone.

Algorithms↗
PubMed2004

Revised 2004 International Classification of Headache Disorders: new headache types.

In 1988, the International Headache Society created a classification system that has become the standard for headache diagnosis and research. The International Classification of Headache Disorders galvanized the headache community and stimulated nosologic, epidemiologic, pathophysiologic, and genetic research. It also facilitated multinational clinical drug trials that have led to the basis of current treatment guidelines. While there have been criticisms, the classification received widespread support by headache societies around the globe. Fifteen years later, the International Headache Society released the revised and expanded International Classification of Headache Disorders second edition. The unprecedented and rapid advances in the field of headache led to the inclusion of many new primary and secondary headache disorders in the revised classification. Using illustrative cases, this review highlights 10 important new headache types that have been added to the second edition. It is important for neurologists to familiarize themselves with the diagnostic criteria for the frequently encountered primary headache disorders and to be able to access the classification (www.i-h-s.org) for the less commonly encountered or diagnostically challenging presentations of headache and facial pain.

Headache↗
PubMed2001

Classification of procedures in the domain of thoracic surgery--a study of reliability in coding.

This paper relates a study of reliability of coding of surgical procedures in the domain of thoracic surgery. The reliability measured is inter-coder variability in form of agreement. Four classifications were used by four physicians on 100 patient cases. The classifications, having differing granularity and structure, were analyzed using a statistical method (kappa). These results are discussed and related to the differences between the classifications. One of the topics for discussion is how the granularity affects the degree of agreement, coupled to the usefulness of the classification. Also the concept of using formal methods for representing classifications is discussed, how this will affect how classifications are designed and used.

Humans↗
PubMed1991

Tests of an exemplar model for relating perceptual classification and recognition memory.

Experiments were conducted in which Ss made classification, recognition, and similarity judgments for 34 schematic faces. A multidimensional scaling (MDS) solution for the faces was derived on the basis of the similarity judgments. This MDS solution was then used in conjunction with an exemplar-similarity model to accurately predict Ss' classification and recognition judgments. Evidence was provided that Ss allocated attention to the psychological dimensions differentially for classification and recognition. The distribution of attention came close to the ideal-observer distribution for classification, and some tendencies in that direction were observed for recognition. Evidence was also provided for interactive effects of individual exemplar frequencies and similarities on classification and recognition, in accord with the predictions of the exemplar model. Unexpectedly, however, the frequency effects appeared to be larger for classification than for recognition.

Adult↗
PubMed2006

Interobserver agreement and reproducibility in classification of invasive breast carcinoma: an NCI breast cancer family registry study.

The United States National Cancer Institute Breast/Ovarian Cancer Family Registry is the largest international Registry of this type; over 37 724 individuals have been enrolled to date. One activity of this Registry is the semicentralized pathologic review of tumors from all probands. Given the semicentralized nature of the review, this study was undertaken to determine the reproducibility, source(s) of classification discrepancies and stratagems to circumvent discrepancies for histologic subtyping and grading of invasive breast cancer among the reviewing pathologists. A total of 13 pathologists reviewed 35 invasive breast cancers and classified them by primary and secondary histologic type, Nottingham grade and score. Lymph-vascular space invasion, circumscribed margins, syncytial growth and lymphocytic infiltrate were also evaluated. A training session using a separate set of slides was conducted prior to the study. General agreement, in terms of category-specific kappa's and percent agreement, and accuracy of classification relative to a reference standard were determined. Classification of histologic subtype was most consistent (and accurate) for mucinous carcinoma (kappa=1.0), followed by tubular (kappa=0.8) and lobular subtypes (kappa=0.8). Classification of medullary subtype was moderate (kappa=0.4), but additional evaluation of degree of lymphocytic infiltrate, syncytial growth and circumscribed margins identified most cases. Category-specific kappa's were moderate to good for Nottingham grade (kappa=0.5-0.7), with the greatest agreement obtained in categorizing grade I (kappa=0.7), and grade III tumors (kappa=0.7). A flexible classification strategy that employs individual and combined criteria provides good interobserver agreement for invasive breast cancers with uniform, unambiguous histology and compensates for classification discrepancies in the more histologically ambiguous or heterogeneous cancers.

Breast↗
PubMed2001

Authentication of Galician (N.W. Spain) quality brand potatoes using metal analysis. Classical pattern recognition techniques versus a new vector quantization-based classification procedure.

The objective of this work was to develop a classification system in order to confirm the authenticity of Galician potatoes with a Certified Brand of Origin and Quality (CBOQ) and to differentiate them from other potatoes that did not have this quality brand. Elemental analysis (K, Na, Rb, Li, Zn, Fe, Mn, Cu, Mg and Ca) of potatoes was performed by atomic spectroscopy in 307 samples belonging to two categories, CBOQ and Non-CBOQ potatoes. The 307 x 10 data set was evaluated employing multivariate chemometric techniques, such as cluster analysis and principal component analysis in order to perform a preliminary study of the data structure. Different classification systems for the two categories on the basis of the chemical data were obtained applying several commonly supervised pattern recognition procedures [such as linear discriminant analysis, K-nearest neighbours (KNN), soft independent modelling of class analogy and multilayer feed-forward neural networks]. In spite of the fact that some of these classification methods produced satisfactory results, the particular data distribution in the 10-dimensional space led to the proposal of a new vector quantization-based classification procedure (VQBCP). The results achieved with this new approach (percentages of recognition and prediction abilities > 97%) were better than those attained by KNN and can be compared advantageously with those provided by LDA (linear discriminant analysis), SIMCA (soft independent modelling of class analogy) and MLF-ANN (multilayer feed-forward neural networks). The new VQBCP demonstrated good performance by carrying out adequate classifications in a data set in which the classes are subgrouped. The metal profiles of potatoes provided sufficient information to enable classification criteria to be developed for classifying samples on the basis of their origin and brand.

Journal Article↗
PubMed1982

Phonological disorders I: a diagnostic classification system.

Data are presented to support the validity and utility of a diagnostic classification system for persons with phonological disorders. Rationale for the classification system is developed from current reviews of issues and concepts in phonology and classification systems. The system proceeds from a worksheet for reduction of phonological and other assessment data, through five hierarchical levels of classification entries. The system will accommodate lower-level elaboration of etiological subgrouping, pending appropriate research. A retrospective classification study of 43 children with delayed speech is described. Procedural details relating classification procedures to two companion papers (Shriberg & Kwiatkowski, 1982a, 1982b) are provided.

Adolescent↗
PubMed2000

A new practical classification of laryngeal view.

A new practical classification of laryngeal view at laryngoscopy is presented and evaluated. The best laryngeal view obtained with or without anterior laryngeal pressure is recorded. The laryngeal view is easy (E) when the laryngeal inlet is visible. The view is restricted (R) when the posterior glottic structures (posterior commissure or arytenoids) are visible or the epiglottis is visible and can be lifted; this includes some grade 2 and some grade 3 views as classified by Cormack and Lehane. A difficult (D) view is present when the epiglottis cannot be lifted or when no laryngeal structures are visible. Five hundred patients were studied. Laryngoscopy, with the patient anaesthetised and paralysed, was performed with a Macintosh laryngoscope. If the vocal cords were not visible, a gum elastic bougie was used to aid intubation. Other aids were used only if this did not allow intubation. Each laryngeal view was graded according to the new classification and that of Cormack and Lehane. Intubation was timed and the equipment needed to facilitate intubation was recorded. The new classification stratified increasing difficulty with intubation (time for intubation longer and increasingly complex methods needed) better than the Cormack and Lehane classification. The new classification is as sensitive and more specific than the Cormack and Lehane classification in predicting difficult intubation. It is also more sensitive and more specific in predicting easy intubation.

Adolescent↗
PubMed2003

Cutaneous lymphomas other than mycosis fungoides in Singapore: a clinicopathological analysis using recent classification systems.

BACKGROUND: Cutaneous lymphomas other than mycosis fungoides (MF) are a heterogeneous group with wide variations in clinical presentation, biological behaviour and prognosis. New classification systems have been designed or proposed in recent years, with well-defined disease entities and emphasis on the importance of site. OBJECTIVES: This study aims to analyse a series of non-MF lymphomas in an institution-based dermatological setting in Singapore, based on the European Organization for Research and Treatment of Cancer (EORTC) classification and the World Health Organization (WHO) classification. A secondary objective is to highlight the clinical utility of both classification systems. PATIENTS AND METHODS: Forty cases diagnosed over a 12-year period were examined by immunohistochemistry with antibodies targeting CD3, CD4, CD5, CD8, CD20, CD30, CD43, CD45RO, CD56 and CD68 in paraffin-embedded specimens. The immunohistological diagnosis was correlated with the clinical presentation and staging investigations for the final diagnosis and the course of disease recorded. RESULTS: Non-MF T-cell lymphomas presenting in the skin comprised 31 cases (78%) and were 3(1/2) times more common than B-cell lymphomas, which comprised nine cases (22%). The common subtypes were lymphomatoid papulosis, CD30+ large cell cutaneous T-cell lymphoma and subcutaneous panniculitis-like T-cell lymphoma. The commonly ascribed B-cell pattern with infiltrates in the mid and deep dermis and perivascular spaces was seen in 60% of T-cell lymphomas. Overall, there were equal numbers of primary cutaneous T-cell lymphomas and those due to concurrent or secondary cutaneous lymphoma. Five of six cases of subcutaneous panniculitis-like T-cell lymphoma had concurrent cutaneous and systemic involvement and their median survival was 7 months. CONCLUSIONS: The predominance of cutaneous T-cell lymphomas in this case series closely matched that reported from east Asia; cutaneous B-cell lymphomas are much less common than in Europe. The EORTC classification, which is designed only for primary cutaneous lymphomas, should be used in conjunction with the WHO classification because of the high prevalence of cutaneous lymphomas as the secondary site of disease from systemic lymphoma. In addition, subcutaneous panniculitis-like T-cell lymphoma is a primary cutaneous lymphoma where systemic involvement is common at initial presentation. We propose full immunophenotyping and complete clinical evaluation with staging investigations for all patients presenting with cutaneous lymphomas other than MF.

Adolescent↗
PubMed2002

Use of the St Gallen classification for patients with node-negative breast cancer may lead to overuse of adjuvant chemotherapy.

BACKGROUND: The 1998 St Gallen classification was devised to guide clinicians in the use of adjuvant systemic therapy for women with early breast cancer. In this study, the classification was applied to a historical group of patients with node-negative breast cancer who were treated without adjuvant therapy. METHODS: The St Gallen classification was applied to 421 women with breast cancer treated with conservative surgery and radiotherapy alone between 1979 and 1994. Primary tumour characteristics were reviewed centrally. RESULTS: When the most stringent version of the St Gallen classification was applied (grade 2 or 3 tumours classified as "high risk"), only 10 per cent of patients were "low risk", with a 10-year distant relapse-free survival (DRFS) rate of 100 per cent, and 15 per cent were at "intermediate risk" (10-year DRFS rate of 94 per cent). The high-risk group (75 per cent of women) had a 10-year DRFS rate of 77 per cent (P < 0.01). If the St Gallen classification had been applied to all patients in this series who were aged less than 70 years, up to 91 per cent would have been recommended to have chemotherapy. CONCLUSION: The St Gallen classification is an inaccurate measure of prognosis for patients with node-negative breast cancer and should be used with caution.

Adult↗
PubMed1999

Clinicopathological analysis of 501 non-Hodgkin's lymphomas in Korea according to the revised European-American classification of lymphoid neoplasms.

AIMS: The clinical relevance of the Revised European-American Classification of Lymphoid Neoplasms (REAL) is still debated. To test the clinical validity of the REAL classification in Korea, where the incidence of T-cell lymphoma is higher, we investigated the clinicopathological features of non-Hodgkin's lymphoma (NHL) from Korea Cancer Center Hospital. METHODS AND RESULTS: Five hundred and one patients with NHL were reclassified according to the REAL classification and clinicopathologically analysed. Immunophenotypically, B-cell lymphoma accounted for 67.9% and T- and NK-cell type for 30.5%. Approximately 48.5% of cases were forms of diffuse large B-cell lymphoma (DLBCL), while only 5.4% were follicular lymphoma. Peripheral T-cell lymphoma unspecified (PTCL-U; 10.8%) and angiocentric lymphomas (11.8%) comprised the majority of T-cell lymphomas. Most of the angiocentric lymphomas presented with localized nasal/nasopharyngeal or tonsillar primaries. All peripheral T-cell lymphomas (PTCL) showed a significantly low overall survival compared to DLBCL (P = 0.02, log rank). Overall survival rates for DLBCL and PTCL-U were also significantly different (P = 0.0043, log rank), though for DLBCL and angiocentric lymphoma there was no significant difference (P = 0.2142, log rank). Angiocentric lymphoma, however, was characterized by a shorter median survival time than DLBCL (54 months vs. 96 months). Among DLBCL patients according to the REAL classification, overall survival was significantly better in nonimmunoblastic type (intermediate-grade, WF-F,G) as compared to large cell immunoblastic type (high-grade, WF-H) (log rank, P < 0.001). The morphological distinction of the immunoblastic and nonimmunoblastic among DLBCL of the REAL classification bears significant prognostic relevance worthy of further consideration. CONCLUSION: We conclude that lineage assignment (T vs. B) in the REAL classification is a clinically important distinction, but that it is necessary to subdivide the broad category of DLBCL.

Adolescent↗
PubMed1998

The regulation of drugs and medicines in horse racing in the United States. The Association of Racing Commissioners International Uniform Classification of Foreign Substances Guidelines.

The primary reason for developing the ARCI Uniform Classification of Foreign Substances was to give stewards and other racing regulators guidelines to assist them in understanding the relative performance effects and general offensiveness to the Rules of Racing of various drugs and medications. As such, these guidelines have been very useful in the world of racing regulation--officially or unofficially--because this classification system, for the first time, places a relative number on the inappropriateness of any one of more than 750 agents appearing in forensic samples taken from racing horses. The guidelines set up by this system established the first framework for dialogue among veterinary pharmacologists reviewing these drugs. Prior to development of the guidelines, pharmacologists had their own opinions about these agents and their effects on performance. The guidelines, however, established a framework for discussion, and there has been surprising unanimity about the classification of each of these agents. Not only does this classification system provide a useful basis for dialogue among experts, it is also useful for regulators, horsemen and other laymen, most of whom have little training or experience with drugs and their effects on horses. The system is easily understandable and communicates the relative possibility of any classified substance to affect the performance of a horse. Consequently, the system has made it possible for laymen to understand the degree of impropriety of all drugs and medicines with which they may have contact. Grouping a large number of drugs into specific classes has greatly facilitated discussion about regulations and penalties, and the classification system is related to proposed penalty guidelines which were developed in parallel. With regard to penalties for Class 1 agents, it is easy to assign and defend substantial penalties after examining the guideline statement describing the possible performance effects of this group of agents as well as the fact that they have no well recognized therapeutic role. Similarly, the relatively modest effects of class 4 and 5 agents, combined with the fact that these groups encompass a large number of well recognized therapeutic agents, helps in understanding the possible presence of trace levels of these agents in post-race samples. In summary, the ARCI Uniform Classification of Foreign Substances Guidelines condenses data on drugs and medications and places them into a simple five class system. This system has made it possible to confidently discuss the regulatory implications of the identification of any one of the approximately 750 classified substances potentially found in forensic samples from a performance horse. As such it facilitates both the development and implementation of more understandable and equitable regulatory processes.

Animals↗
PubMed2003

Clinical study of primary cutaneous B-cell lymphoma using both the European Organization for Research and Treatment of Cancer and World Health Organization classifications.

Primary cutaneous B-cell lymphoma (PCBCL) is rare, with few series reported in the literature. Its classification and treatment remain controversial. Biopsy specimens of 13 patients with PCBCL were classified according to both the European Organization for Research and Treatment of Cancer (EORTC) and the new World Health Organization (WHO) classifications. Treatment and clinical outcomes were documented. Using the EORTC classification there were seven men and six women aged 32-85 years (mean = 51 years) with follicle centre cell (FCC) lymphoma (nine), immunocytoma (two) and primary cutaneous large B-cell lymphoma of the leg (PCLBCL-leg) (two). When the WHO classification was used, the nine patients with FCC were reclassified as follicle centre (five) and diffuse large B-cell lymphoma (four). Most patients had localized disease (12). Initial treatment consisted of radiotherapy alone (seven), combination chemotherapy alone (one), combined chemoradiotherapy (three) and surgery (two). Twelve patients achieved complete remission (median follow up 28 months, range 10-167 months). One patient with PCLBCL-leg died from progressive cutaneous disease. Most localized PCBCL lesions (except PCLBCL-leg) have a favourable prognosis. We recommend that clinicians be familiar with the important differences in the EORTC and WHO classifications. Further large prospective studies comparing the WHO and EORTC classifications are required to more clearly delineate the outcomes of the increasing number of patients who are classified as DLBCL by the WHO system.

Adult↗