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The Lukes-Collins and Kiel classifications for non-Hodgkin lymphomas. A retrospective study considering both classifications and their relationships to stage, sex, age, and survival.

359 patients with non-Hodgkin lymphomas referred to Oulu University Hospital between 1964 to 1981, inclusive, were reclassified histologically according to the criteria of Lukes-Collins as well as Lennert's histological classifications. The requirements to enter this study were fulfilled only in 280 cases. After the evaluation of the results certain observations emerged. Firstly, within the Lukes-Collins classification: Nodularity was predominantly related to the SC and LC types. Nodularity is indicative of better survival. The Lukes-Collins classification correlates well with clinical stage as well as with age. The Burkitt and convoluted types were found to be predominantly related to childhood or to younger patients and the non-Burkitt type most frequently to the older groups. The Lukes-Collins classification separates well two clear prognostic groups, the favourable group (LC, SC, PC, and SL types), with an overall median survival of 44 months, and the unfavourable group (LNC, IS, convoluted, undefined, and SNC types), with an overall median survival of 11 months. No differences in survival were observed between the LNC, LC, and IS diffuse types. Stage, general symptoms and laboratory findings were also evaluated. Secondly, within the Kiel classification: Nodularity has been found mainly in the CB-CC type, but also in 27% of the CC cases. The relationship of the subtypes according to the Kiel classification and age resembles the same relation found with the Lukes-Collins classification. According to the Kiel classification, the Burkitt, convoluted, and lymphoblastic types were related to children and young adults. A proportion of the LB type occurs also in older groups. Three prognostic groups were identified, the favourable (CB-CC foll. and PC types), with an overall median survival in excess of 80 months, an intermediate group (CB-CC foll. - diff., CC, and CLL), with an overall median survival of 38 months, and an unfavourable group (Conv, CB, CB-CC diff., UC, IB, and Burkitt types), with a median survival of 11 months. The CC type in this study was controversial in its morphological acceptability.

Adolescent↗
PubMed1999

An imaging-based classification for the cervical nodes designed as an adjunct to recent clinically based nodal classifications.

Over the past 18 years, numerous classifications have been proposed to distinguish among the diverse nodal levels. Some classifications have used surgical landmarks, others physical assessment criteria. These classifications do not agree precisely and exhibit sufficient variation that competent physicians could arrive at slightly different staging of the patient's nodal disease. In the past 2 decades, computed tomography and magnetic resonance imaging have offered progressively more refined anatomical precision, reproducibility, and visualization of deep, clinically inaccessible structures. Because the majority of patients with head and neck malignancies presently undergo sectional imaging prior to treatment planning, we felt a need to integrate anatomical imaging criteria with the 2 most commonly used nodal classifications: those of the American Joint Committee on Cancer and those of the American Academy of Otolaryngology-Head and Neck Surgery. The imaging-based nodal classification proposed herein has been developed in consultation with surgeons interested in such classifications in the hope that the resultant classification would find ready acceptance by both clinicians and imagers. It is our desire that the best attributes of imaging, combined with those of the physical assessment, can result in a better and more consistently reproducible nodal staging than is possible by either

Head and Neck Neoplasms↗
PubMed1982

National Cancer Institute sponsored study of classifications of non-Hodgkin's lymphomas: summary and description of a working formulation for clinical usage. The Non-Hodgkin's Lymphoma Pathologic Classification Project.

An international multi-institutional clinicopathologic study of 1175 cases of non-Hodgkin's lymphoma sponsored by the National Institute has been completed. Histologic slides and clinical records were examined from previously untreated patients seen during the period between July 1971 and December 1975 at four institutions, three in the United States and one in Italy. The reproducibility and clinical relevance of the six major classifications of the non-Hodgkin's lymphomas was tested by six "expert" pathologists, each a proponent of a major classification, and six very experienced pathologists not identified with one of the major classifications. Immunologic methods were not employed in the study design. A summary of the methods employed and the conclusions of the study is described. The major conclusion was that all six classifications were valuable and comparable in reproducibility and clinical correlations. The clinical significance of a follicular architecture, independent of cell type was confirmed. A working formulation of non-Hodgkin's lymphomas is described which separates the disease into ten major types utilizing morphologic criteria only. Subtypes are also described which allow translation of all of the major classifications into comparable groups. Histologic criteria are presented for each major type and equivalent terms are given for each type in the six major classifications. The formulation is not proposed as a new classification but a means of translation among the various systems and to facilitate clinical comparisons of case reports and therapeutic trials. The report contains commentaries by five of the "expert" pathologists on the value and conclusions of this unique study.

Actuarial Analysis↗
PubMed2005

Comparison of the Radiation Therapy Oncology Group recursive partitioning classification and Union Internationale Contre le Cancer TNM classification for patients with head and neck carcinoma.

BACKGROUND: Prognostic models need to be tested in external validation studies to assess generalizability. Recursive partitioning analysis (RPA), a prognostic system based on the creation of a classification tree, has been proposed as a classification method in patients with head and neck carcinoma. The aim of this study was to compare the RPA and Union Internationale Contre le Cancer (UICC) TNM classification systems in patients with head and neck carcinoma treated consecutively in a single center. METHODS: A total of 2166 patients with carcinomas of the oral cavity, oropharynx, hypopharynx, and larynx was classified according to both the RPA and the TNM classification systems, and the results were compared. The endpoints considered were observed survival and survival free of locoregional tumor. The two methods of classification were evaluated objectively by use of measures of intrastage homogeneity (hazard consistency), interstage heterogeneity (hazard discrimination), predictive power (outcome prediction), and patient distribution between stages (balance). RESULTS: When the endpoint considered was observed survival, there were no clinically relevant differences between the two classifications. However, when the endpoint was locoregional control, the RPA system was sensitive to the type of treatment used, and it was not generalizable. CONCLUSIONS: To evaluate generalizability, new classification proposals need external validation studies that objectively measure the quality of the model. The performance of the RPA system was not reproducible in our cohort of patients when the endpoint evaluated was locoregional control.

Head and Neck Neoplasms↗
PubMed2005

Protein classification based on text document classification techniques.

The need for accurate, automated protein classification methods continues to increase as advances in biotechnology uncover new proteins. G-protein coupled receptors (GPCRs) are a particularly difficult superfamily of proteins to classify due to extreme diversity among its members. Previous comparisons of BLAST, k-nearest neighbor (k-NN), hidden markov model (HMM) and support vector machine (SVM) using alignment-based features have suggested that classifiers at the complexity of SVM are needed to attain high accuracy. Here, analogous to document classification, we applied Decision Tree and Naive Bayes classifiers with chi-square feature selection on counts of n-grams (i.e. short peptide sequences of length n) to this classification task. Using the GPCR dataset and evaluation protocol from the previous study, the Naive Bayes classifier attained an accuracy of 93.0 and 92.4% in level I and level II subfamily classification respectively, while SVM has a reported accuracy of 88.4 and 86.3%. This is a 39.7 and 44.5% reduction in residual error for level I and level II subfamily classification, respectively. The Decision Tree, while inferior to SVM, outperforms HMM in both level I and level II subfamily classification. For those GPCR families whose profiles are stored in the Protein FAMilies database of alignments and HMMs (PFAM), our method performs comparably to a search against those profiles. Finally, our method can be generalized to other protein families by applying it to the superfamily of nuclear receptors with 94.5, 97.8 and 93.6% accuracy in family, level I and level II subfamily classification respectively.

Algorithms↗
PubMed2002

The National Vegetation Classification Standard applied to the remote sensing classification of two semiarid environments.

The National Vegetation Classification Standard (NVCS) was implemented at two US National Park Service (NPS) sites in Texas, the Padre Island National Seashore (PINS) and the Lake Meredith National Recreation Area (LMNRA), to provide information for NPS oil and gas management plans. Because NVCS landcover classifications did not exist for these two areas prior to this study, we created landcover classes, through intensive ground and aerial reconnaissance, that characterized the general landscape features and at the same time complied with NVCS guidelines. The created landcover classes were useful for the resource management and were conducive to classification with optical remote sensing systems, such as the Landsat Thematic Mapper (TM). In the LMNRA, topographic elevation data were added to the TM data to reduce confusion between cliff, high plains, and forest classes. Classification accuracies (kappa statistics) of 89.9% (0.89) and 88.2% (0.87) in PINS and LMNRA, respectively, verified that the two NPS landholdings were adequately mapped with TM data. Improved sensor systems with higher spectral and spatial resolutions will ultimately refine the broad classes defined in this classification; however, the landcover classifications created in this study have already provided valuable information for the management of both NPS lands. Habitat information provided by the classifications has aided in the placement of inventory and monitoring plots, has assisted oil and gas operators by providing information on sensitive habitats, and has allowed park managers to better use resources when fighting wildland fires and in protecting visitors and the infrastructure of NPS lands.

Conservation of Natural Resources↗
PubMed2005

The VCUAM (Vagina Cervix Uterus Adnex-associated Malformation) classification: a new classification for genital malformations.

OBJECTIVE: With an incidence of up to 5% in the general population, genital malformations are a frequent clinical occurrence. However, using the existing published classifications of malformations, difficulties arise in classifying genital malformations appropriately. The aim of the present study was to produce a simple, systematic, and reproducible classification system. DESIGN: A systematic arrangement of genital and associated malformaltions, using a structure similar to that in the TNM classification of oncological tumors, was developed and validated. SETTING: Patients with genital malformations in a university hospital. PATIENT(S): Ninty-nine premenopausal patients with genital malformations. INTERVENTION(S): Patients were diagnosed for genital malformation using laparoscopy or magnetic resonance imaging. MAIN OUTCOME MEASURE(S): A new classification (VCUAM) is presented to evaluate patients with different genital malformations. RESULT(S): The external and internal female genital organs were divided into the following subgroups in accordance with the anatomy: vagina (V), cervix (C), uterus (U), and adnexa (A). Associated malformations were assigned to a subgroup (M) relative to each specific organ. The classification was validated in a group of 99 patients with genital malformations. CONCLUSION(S): The VCUAM classification for the first time makes it possible to reflect even complex malformations in a precise and individual fashion, taking associated malformations into account. The classification makes it easier to provide appropriate clinical care for the affected patients.

Abnormalities, Multiple↗
PubMed2003

Lack of agreement in classification of the severity of acute asthma between emergency physician assessment and classification using the National Asthma Council Australia guidelines (1998).

AIMS: To determine the level of agreement in classification of the severity of acute asthma at presentation to the emergency department, between emergency physician global assessment and severity classification according to the National Asthma Council Guidelines, Australia 1998 (NACG). METHODS: Prospective observational study in emergency departments throughout Australia, participating in the Asthma Snapshot 2000 project. Patients between the ages of one and 60 years presenting to participating emergency departments with acute asthma between 21 August and 3 September 2000 were included. Data collected were emergency physician global assessment of asthma severity and severity classification according to the National Asthma Council Guidelines and disposition. RESULTS: Five hundred and five subjects had completed data for emergency physician assessment of severity and for calculation of severity classification according to the National Asthma Council Guidelines. Weighted kappa for agreement in classification was 0.48 (95% confidence interval: 0.40, 0.56). Emergency physicians assess asthma as less severe compared to the National Asthma Council Guidelines assessment. CONCLUSIONS: Agreement between physician assessment of severity of acute asthma and severity classification according to National Asthma Council Guidelines is only moderate. This may have implications in treatment and disposition. This also suggests that emergency physicians may be using other methods to classify acute asthma than the National Asthma Council Guidelines classification.

Asthma↗
PubMed2004

Classification of perinatal deaths: development of the Australian and New Zealand classifications.

Classifications of perinatal deaths have been undertaken for surveillance of causes of death, but also for auditing individual deaths to identify suboptimal care at any level, so that preventive strategies may be implemented. This paper describes the history and development of the paired obstetric and neonatal Perinatal Society of Australia and New Zealand (PSANZ) classifications in the context of other classifications. The PSANZ Perinatal Death Classification is based on obstetric antecedent factors that initiated the sequence of events leading to the death, and was developed largely from the Aberdeen and Whitfield classifications. The PSANZ Neonatal Death Classification is based on fetal and neonatal factors associated with the death. The classifications, accessible on the PSANZ website (http://www.psanz.org), have definitions and guidelines for use, a high level of agreement between classifiers, and are now being used in nearly all Australian states and New Zealand.

Australia↗
PubMed1977

Visual classification of banded human chromosomes ii. classification and karyotyping of integrated density profiles.

Visual classification and karyotyping of 897 integrated density profiles generated from straight and non-overlapping chromosomes from 22 trypsin-banded metaphases of average quality was carried out and evaluated. The results were compared with visual classification of photographic prints of the same 897 chromosomes. The experiments were carried out by one observer. About 5% errors were made in classification of isolated profiles; 0-5% errors were made in karyotyping profiles and about 3% errors were made in classification of isolated chromosome prints. The reason for the small error rate obtained by karyotyping profiles as compared to the error rate when classifying isolated profiles was assumed to be the use of a priori knowledge of the composition of (normal) metaphases and the possibility of making appropriate comparisons between the individual profiles within the metaphase. Comparison between classification of isolated prints and of profiles showed different error patterns on the basis of which it was assumed that prints constitute a better basis for visual classification than profiles. The results seemed to indicate two ways of improving computer classification of banded chromosomes: (1) information of value in the chromosomes (band pattern, shape etc.) should be extracted from the digitized chromosome image in a manner superior to the simple integration by which profiles are produced; (2) computer karyotyping should simulate the human method, thus taking advantage of a priori knowledge of the composition of the metaphases and being able to make appropriate comparisons between individual chromosomes.

Chromosomes↗
PubMed2004

Validity of the WHO operational classification and value of other clinical signs in the classification of leprosy.

The objective of this study is to examine the validity of the WHO operational classification using skin smear results as the gold standard and explore the value of additional clinical signs independently and in combination with the WHO classification. Between 1985 and 2000, 5439 new untreated leprosy patients were registered at the Schieffelin Leprosy Research and Training Center, Karigiri. They were classified according to the Ridley Jopling classification as well as WHO operational classification based on the number of skin lesions. The sensitivity and specificity of the WHO operational classification tested, using skin smear results as the gold standard, was found to be 88.6% and 86.7% respectively. The Receiver Operator Characteristic (ROC) curve confirms that the best option for sensitivity and specificity is a cut off of 6 and more lesions for MB. The validity of the number of enlarged nerves and size of the largest skin lesion as independent criteria to classify patients was found to be poor. Addition of three enlarged trunk nerves to the WHO classification improved its sensitivity to 91.4%, while the specificity remained almost unchanged at 85.3%. Addition of the size of the largest skin lesion to the WHO classification reduced its validity considerably. The study concludes that the WHO recommendation of using six and more lesions for classifying a patient as MB is the best option available at the moment, and calls for further research to identify other clinical criteria that have a better validity and could be easily applied in the field.

Humans↗
PubMed1976

[A proposal of a T.N.M. type of classification of the ear. O.P.A.C. classification of chronic surgical otitis].

With the advent of modern otology, cophosurgeons anxious to compare their results soon became aware of the need for a "T.N.M" type of classification for the ear. The classification described here by the authors is, in principle, a classification of the "T.N.M" type: that is, a purely descriptive classification without prognostic, pathogenetic or therapeutic pretensions. This "O.P.A.C." classification is based on a description of 4 main characteristics: 1) the existence and characteristics of potential otorrhoea, described under the letter C; 2) the characteristics of potential perforation of the tympanum, described under the letter P; 3) the appearance of the middle ear, excluding the ossicular chain, described under the letter A; 4) the condition of the ossicular chain when the surgeon has completed his exploration of the lesions, described under the letter C. Two years experience seems to have proved the convenience and usefulness of this purely clinical classification, providing otologists with a common language. While they are aware of the objections and criticisms to which it may give rise, the authors hope, on time, to improve in this classification.

Cerebrospinal Fluid Otorrhea↗
PubMed2003

Relative frequency of the different types of cutaneous T cell and natural killer cell lymphomas in Korea based on the proposed WHO classification and the EORTC classification.

The R.E.A.L. classification was largely adopted recently by the proposed WHO classification. The usefulness of this classification in cutaneous T cell and natural killer (NK) cell lymphomas in Korea was evaluated compared to that of the European Organization for Research and Treatment of Cancer (EORTC) classification. Overall, 78 patients with cutaneous T cell and NK cell lymphomas were diagnosed in Asan Medical Center in the 1990's. The clinical records, slides of H&E and immunohistochemical stainings were reviewed. By the proposed WHO classification, mycosis fungoides (20 cases), lymphomatoid papulosis (13 cases), nasal type NK/T-cell lymphoma (10 cases), CD30+ anaplastic large cell lymphoma (8 cases), subcutaneous panniculitis-like T-cell lymphoma (6 cases), peripheral T-cell lymphoma, unspecified (3 cases), Sézary syndrome (1 case) and blastic NK cell lymphoma (1 case) comprised the primary cases. Secondary or undetermined cases included peripheral T-cell lymphoma, unspecified (10 cases), nasal type NK/T-cell lymphoma (5 cases), and angioimmunoblastic T-cell lymphoma (1 case). EORTC classification for cutaneous T cell and NK cell lymphomas did not include nasal and nasal type NK/T-cell lymphomas, unspecified non-pleomorphic T-cell lymphoma, undetermined cases among primary or secondary ones and some rare types of skin lymphomas which can be classified by WHO. The WHO classification is more useful for skin lymphomas in Korea since it encompassed all the various types of skin T cell and NK cell lymphomas in Korea.

Adolescent↗
PubMed2004

[Another seizure classification--Semiological Seizure Classification].

The International League Against Epilepsy (ILAE) introduced in 1981 a seizure classification based on clinical semiology, interictal EEG findings, and ictal EEG patterns. Such classification depends heavily on detailed electroclinical correlation. After 20 years' progress in epileptology, many clinicians have found it difficult to make a "definite" seizure diagnosis clinically without a series of electrophysiological examinations, particularly in the infants, and further advancement in epileptology has findings have made the previous classification inefficient. Lüders and colleagues have proposed a classification, Semiological Seizure Classification (SSC), based exclusively on ictal semiology, which was published in the official journal of ILAE-EPILEPSIA in 1998. The EEG, neuroimaging and other laboratory results should be analyzed separately and then integrated to define the epileptic syndromes. The seizure diagnosis is thus made through a "what-you-see-is-what-you-get" way. It has also provoked an extensive discussion about the necessity of this new classification. In this review, we present the original guideline, which has been used at The Cleveland Clinic Foundation for years, to introduce another method of epileptic seizure classification.

Adult↗
PubMed1987

[The Lukes-Collins classification and the Kiel classification of non-Hodgkin's lymphomas].

280 cases of non-Hodgkin lymphoma were studied histologically according to the criteria of Lukes-Collins as well as Lennert's classifications. Nodularity was predominantly related to the SC and LC types according to the Lukes-Collins classification. Nodularity is indicative of better survival. The Burkitt and convoluted types were found to be predominantly related to childhood or to younger patients and the non-Burkitt type most frequently to the older groups. The Lukes-Collins classification separates well two clear prognostic groups--the favorable and the unfavorable one with overall median survivals of 44 and 11 months, respectively. Within the Kiel classification, nodularity was found mainly in the CB-CC type, but also in 27% of the CC cases. The relationship of the subtypes according to the Kiel classification and age resembles the same relation found with the Lukes-Collins classification, where according to the Kiel classification the Burkitt, convoluted and lymphoblastic types were related to children and adults. Three prognostic groups were identified with overall median survivals of 80, 38 and 13 months, respectively.

Adolescent↗
PubMed1998

Stage classifications of pancreatic cancer: comparison of the Japanese and UICC classifications and proposal for a new staging system. Union Internationale Contre le Cancer.

In the 4th edition of General Rules for the Study of Pancreatic Cancer by the Japan Pancreas Society (JPS), published in 1993 (English version published in 1996), a system resembling the TNM classification by the Union Internationale Contre le Cancer (UICC) was adopted, based on the results of precise analysis of data from 11,317 cases of carcinoma of the pancreas registered by the JPS during the 10-year period from 1981 to 1990. We compare the two TNM classifications and staging groups, focusing on the simplicity and reproducibility of the diagnostic criteria and the reliability of predicting outcome. To compare the prognostic value of the two classification systems, we analyzed the published data on resected cases registered by Pancreatic Cancer Registration Committee of the JPS. The results showed that a major drawback of the JPS classification is that is difficult to apply and has poor reproducibility. Survival rates differed significantly among the four stages in the JPS classification, whereas the UICC staging system did not reflect differences in outcome among the four stages, especially between stages II and III. The prognostic value of the UICC T category is better than that of the JPS T category, whereas the N category of JPS has better prognostic value than that of the UICC system. Believing that a combination of the two systems would solve this problem, we propose a new TNM classification and stage-grouping system that draws on the merits of both. This new system may provide improvements in staging classification that will lead to the establishment of a more practical and universal staging system for ductal carcinoma of the pancreas.

Humans↗
PubMed1976

Visual classification of banded human chromosomes. I. Karyotyping compared with classification of isolated chromosomes.

Visual karyotyping and visual classification of isolated chromosomes was carried out by seven investigators on 22 trypsin banded metaphases of average quality. The karyotyping experiment resulted in an average error rate of 0-1% (zero-0-4%) and the classification of isolated chromosomes resulted in an error rate of 3% (2-5%). The B and F group chromosomes were found to be most difficult to classify when isolated, while no errors were made of the no. 1 and the X chromosome. Large differences were seen in the resulting error pattern for the individual investigators both with regard to their total error rate and also the chromosome types which they most frequently misclassified. Based upon these error patterns it is suggested that more than 95% of the chromosomes in an average quality material contain features upon which a reliable visual classification can be made. Thus there may be a potential possibility that these chromosomes may be classified by computer on the basis of these features. The fact that visual karyotyping is much more reliable than visual classification of isolated chromosomes indicated that computer classification of chromosomes should include programming capable of making appropriate comparison between the chromosomes in the metaphase and at the same time take into account the expected presence of 23 chromosome pairs for normal cells. This would simulate the human performance of visual karyotyping and make a classification possible of at least some of the remaining 5% difficult chromosomes.

Chromosomes↗