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PubMedDate not supplied

Problems in the N-classification of the new 1997 UICC TNM stage classification for gastric cancer: an analysis of over 10 years' outcome of Japanese patients.

BACKGROUND: One of the major changes in the new TNM classification (5th edition, 1997) for gastric cancer was made in the classification of N category: the 5th edition employs the number of involved nodes and a minimum of 15 examined nodes is required for N0 classification. The validity of the new TNM classification was assessed by comparing the survivals according to the number of nodal involvement and especially the cut-off point of number of involved nodes and the problems in N0 classification in T1 were focused. PATIENTS AND METHODS: Between 1982 and 1999, a total of 641 patients underwent gastrectomy for gastric cancer in our department. The stage and the degree of subcategories were classified according to the pathological assessment after surgery, and the survival and its correlation with clinicopathological factors were statistically analyzed. RESULTS: pT classification included 325 pT1, 103 pT2, 102 pT3 and 111 pT4 cases, while pN classification included 448 pN-classifiable cases (223 pNO, 149 pN1, 52 pN2 and 24 pN3); 193 were unclassifiable (pNx), 123 of which were classified pNx due to the examined lymph nodes being less than 15. In 448 pTNM-classifiable cases the pN2 and pN3 groups showed almost the same survivals, while the pN1 included subgroups with a significant difference in prognosis. The pN1 category should be classified into two categories: pN1a, 1-3 involved nodes and pN1b, 4-6 involved nodes. Furthermore, out of 325 pT1 cases, 151 (46.5%) were pN-unclassifiable (pNx): 123 were due to the examined number being less than 15 for pN0 classification and 28 where the number of examined nodes were not reported. Although the mean number of examined nodes in pT1 was 24.7 for pN0 and 8.3 for pNx, there were no differences in survival rates between the pT1pN0 group and the pT1pNx group. This suggests the over-requirement of the number of examined nodes for pN0 classification in pT1 cases. We propose that pN0 classification in pT1 should be required for a minimum of 6 examined nodes. CONCLUSION: The pN1 category should be subclassified into pN1a and pN1b. Furthermore, pN0 classification in pT1 should be required for a minimum of 6 examined nodes.

Adult↗
PubMed2002

Classification for congenital anomalies of the hand: the IFSSH classification and the JSSH modification.

The purpose of a classification for clinical problems which, except for a few specialized centers, occur only sporadically is to provide a system where these cases can be stored. This should allow all involved investigators to speak the same language; so-doing syndromes can be delinated, frequencies of occurence established and results of--different--treatments compared. A classification system should be simple to use, reliable and uniformly accepted. It should allow space for adaptations and/or extensions. The IFSSH proposed a 7 categories classification based on the proposed classification of Swanson et al. in 1976. This classification, was based on, which was thought in the seventies, etiopathogenic pathways. These 7 groups are: I. Failure of formation; transverse (A), or longitudinal (B) II. Failure of differentiation III. Polydactyly IV. Overgrowth V. Undergrowth VI. Amniotic band syndrome VII. Generalized skeletal syndromes. The extended classification proposed by IFSSH was used to classify 1013 hand differences in 925 hands of 650 patients. We found associated anomalies in 26.7%. The classification was straightforward in 86%, difficult in 6.6% and not possible in 7.8%. Group II was the most numerous group including 513 anomalies. We propose to include in this group the Madelung deformity, the Kirner deformity and congenital trigger fingers and trigger thumbs. In group I the radial and ulnar deficiencies, limited to the hand without forearm deficlencies should be Included. Triphalangeal thumbs are a problem, we suggest it to be listed in group III and consider it as a duplication in length. It is not always possible to evaluate the (transverse) absence of the fingers or hand. Longitudinal deficiencies (group IIB), symbrachydactyly (group V), and amniotic bands (group IV) occasionally develop a phenotype similar to the genuine transverse deficiency (group IA). Recently, the Japanese Society for Surgery of the Hand (JSSH) (16) proposed an extension/modification of the IFSSH classification. Based on newer knowledge on teratology, symbrachydactyly in all stages were transfered to group I. Two new groups were introduced. A group "failure of finger ray induction" including typical cleft hand (IC), central polydactyly (III) and (bony) syndactyly (II)--was included. Also a group of "unclassifiable" cases was added. This Japanese proposed classification is a real improvement and most clinicians and surgeons tend to use it in the future.

Female↗
PubMed1999

Evaluation of the New American Joint Committee on Cancer/International Union against cancer classification of lymph node metastasis from gastric carcinoma in comparison with the Japanese classification.

BACKGROUND: A new system for the classification of gastric carcinoma, based on the number of metastatic lymph nodes, has been adopted by the current American Joint Committee on Cancer/International Union Against Cancer (AJCC/UICC) TNM system (1997). The purpose of this study was to evaluate the rationality of this classification in comparison with the Japanese classification, which is based on the location of positive lymph nodes. METHODS: The authors analyzed 587 patients who underwent clinically curative gastrectomy with D2 lymphadenectomy for gastric carcinoma and each had 15 or more lymph nodes histologically examined from 1982 to 1992. Multivariate analysis with the Cox proportional hazards model was carried out to determine which classification was more effective. RESULTS: Within the pN1 or pN2 category of the new AJCC/UICC system, no significant difference in the survival rates existed between n1 patients and n2 patients of the Japanese classification. On the other hand, the survival rates significantly decreased, in the order of pN1, pN2, and pN3 (from greatest to smallest decrease), within the n1 and n2 categories. In multivariate analysis, lymph node involvement by the AJCC/UICC classification was selected as the most significant prognostic determinant, whereas the Japanese lymph node classification was not significantly prognostic. When survival rates were calculated within the pT1, pT2, and pT3-4 categories, no differences existed between pN0 and pN1. There was some discrepancy between the survival rate for each pT and pN category and the corresponding stage. CONCLUSIONS: The new AJCC/UICC classification for lymph node involvement of gastric carcinoma is basically acceptable and considered superior to the Japanese classification. Further analysis involving a greater number of cases may be necessary to confirm the applicability of this staging system.

Adult↗
PubMed1997

Research methodology: Coding perceived morbidity in general practice--an evaluation of the Read Classification and the International Classification of Primary Care (ICPC).

OBJECTIVES: To evaluate the Read Classification and the International Classification of Primary Care (ICPC). METHODS: The Read Classification was used to code the diagnoses for 3474 patient encounters, in a pilot sample of three volunteer practices (11 general practitioners), and the ICPC was used to code 21,416 patient encounters in a stratified quota sample of 22 practices (59 general practitioners), in a survey aiming to relate prescribing to perceived diagnosis. RESULTS/EXPERIENCE: The Read Classification was found to be a detailed and exhaustive classification of medical diagnoses, but it was more time consuming to use than the ICPC, due to the complexity of the classification, the over-use of alpha characters compared to the ICPC, and the mixing of alpha characters with numeric digits within the codes. Encoding, decoding and statistical analysis were found to be more straightforward using the ICPC compared with the Read Classification. The ICPC was found to be deficient in 40 important diagnoses, and these are listed. CONCLUSION: The Read Classification was of limited value in this drug utilization survey, in that the design of the code reduced its utility in statistical analyses. The ICPC was an efficient code, which met the criteria of exclusiveness, usefulness and hierarchy. The classification is not exhaustive enough to prevent loss of information as a result of coding, but the authors' amendments virtually eliminated this problem.

Journal Article↗
PubMed2004

Classification of pancreatic cancer: comparison of Japanese and UICC classifications.

The Japan Pancreas Society (JPS) published the fifth Japanese edition of the General Rules for the Study of Pancreatic Cancer in 2002, the same year that the Union Internationale Contre le Cancer (UICC) published its sixth edition. The JPS fifth edition had been revised, based on data from 18,629 cases of carcinoma of the pancreas registered by the JPS (1981-1996) with the goal of making the General Rules simple, easy to understand, and reliable for predicting outcome. The 2 classifications are compared by analyzing the data on 3979 resected patients with tubular adenocarcinoma of the pancreatic head registered by the JPS, focusing on the reliability of predicting outcome. In the extent of the primary tumor (T category), survival rates differed significantly among the 4 groups (T1, T2, T3, T4) in the JPS and UICC classifications. In the extent of lymph node metastasis (N category), survival rates differed significantly among the 4 groups (N0, N1, N2, N3) in the JPS classification and also did significantly between the 2 groups (N0, N1) in the UICC classification. In the stage grouping, however, 2 classifications differed considerably. More than half of the cases of UICC stage II are equivalent to JPS stage IV. Comparison of survival curves according to stage reveals that stratification is much better in the JPS classification than in the UICC classification. These results indicate that the JPS classification is more reliable for predicting outcome as compared with the UICC classification.

Adenocarcinoma↗
PubMed2002

Curve prevalence of a new classification of operative adolescent idiopathic scoliosis: does classification correlate with treatment?

STUDY DESIGN: A retrospective multicenter consecutive case review of operative adolescent idiopathic scoliosis. OBJECTIVES: To define the curve prevalence of a large consecutive series of cases with operative adolescent idiopathic scoliosis as classified by a new system and to test the ability of this new classification system to correlate with regions of the scoliotic spine to be instrumented/fused. SUMMARY OF BACKGROUND DATA: A new comprehensive, two-dimensional classification system, intended to be treatment based, has been developed. However, it has not been tested whether all presenting operative cases of adolescent idiopathic scoliosis are classifiable in a large consecutive series, nor has the prevalence of specific curve types been determined. In addition, it is unknown whether this classification is truly treatment based, as to whether it can correlate with regions of the spine to be instrumented/fused. METHODS: A multicenter retrospective review of 606 consecutive operative cases of adolescent idiopathic scoliosis was performed. All cases were classified by a new triad classification system, which included the following: a curve type (1-6), a lumbar spine modifier (A, B, C), and a sagittal thoracic modifier (-, N, +). Prevalence of the individual three components of the system and the classification grouping of all three components together were performed. In addition, the authors assessed whether this system could correlate with regions of the spine that should be included in the instrumentation and fusion, based on exactly which regions were fused during the operative procedure. RESULTS: All 606 cases were classifiable by this system. Prevalence of the six curve types noted was as follows: Type 1, main thoracic (n = 305, 51%); Type 2, double thoracic (n = 118, 20%); Type 3, double major (n = 69, 11%); Type 4, triple major (n = 19, 3%); Type 5, thoracolumbar/lumbar (n = 74, 12%); and Type 6, thoracolumbar/lumbar-main thoracic (n = 17, 3%). The five most common curve classifications noted were as follows: 1AN, 1BN, 2AN, 5CN, and 1CN, which accounted for 58% of all curve classifications noted. An average of 90% of the operative cases had surgically structural regions of the spine included in the instrumentation and fusion as predicted by the curve type. CONCLUSIONS: A new comprehensive classification system for operative adolescent idiopathic scoliosis found all 606 consecutive cases of adolescent idiopathic scoliosis classifiable, with the Type 1, main thoracic curve pattern, the most common curve type found (51%). This new classification system appears to correlate with treatment of surgically structural regions of the spine fused in 90% of cases by the objective radiographic criteria used.

Adolescent↗
PubMed2003

New glaucoma classification method based on standard Heidelberg Retina Tomograph parameters by bagging classification trees.

PURPOSE: In this article we propose and evaluate nonparametric tree classifiers that can handle non-normal data and a large number of possible predictors using the full set of standard Heidelberg Retina Tomograph measurements for classifying glaucoma. METHODS: The classifiers were trained and tested using standard Heidelberg Retina Tomograph parameters from examinations of 98 subjects with glaucoma and 98 normal subjects of the Erlangen Glaucoma Registry. All patients and control subjects were evaluated by 15 degrees -optic disc stereographs, Heidelberg Retina Tomograph measurements, standard computerized white-in-white perimetry, and 24-hour-intraocular pressure profiles. The subjects were matched by age and sex. Standard classification trees as well as bagged classification trees were used. The classification outcome of the trees was compared with the classification by two published linear discriminant functions based on Heidelberg Retina Tomograph variables with respect to their cross-validated misclassification error. RESULTS: The bagged classification tree had the lowest misclassification error estimate of 14.8% with a sensitivity of 81.6% at a specificity of 88.8%. The cross-validated error rates of the two linear discriminant function procedures were 20.4% (sensitivity 82.6%, specificity 76.7%) and 20.6% (sensitivity 81.4%, specificity 77.3%) for our set of observations. Bagged classification trees were able to reduce the misclassification error of glaucoma classification. CONCLUSIONS: Bagged classification trees promise to be a new and efficient approach for glaucoma classification using morphometric 2- and 3-dimensional data derived from the Heidelberg Retina Tomograph, taking into account all given variables.

Case-Control Studies↗
PubMed2006

The SRS classification for adult spinal deformity: building on the King/Moe and Lenke classification systems.

STUDY DESIGN: Descriptive study of the Scoliosis Research Society (SRS) Classification for Adult Spinal Deformity using interobserver reliability measures for validation of the system. OBJECTIVES: To propose and validate a classification system for adult spinal deformity that will have utility in reporting on treatment options and outcomes for affected adults. SUMMARY OF BACKGROUND DATA: Classification systems exist for adolescent idiopathic scoliosis and have utility in categorizing spinal deformity and guiding choices for management. Adult spinal deformity is distinct from adolescent deformity. Important distinctions include present impairment and pain, regional and global decompensation, and degenerative changes within the deformity. A useful classification system for adult spinal deformity does not exist. The absence of a classification system for adult deformity compromises the ability to report on similar cases and to develop an evidence-based approach to care. METHODS: Descriptive study design with development of an SRS Classification System using the Delphi Method. Validation of the system using interobserver reliability measures based on responses of SRS-member surgeons to radiographic case presentations. RESULTS: Nineteen surgeons evaluated 25 cases of adult spinal deformity. Interobserver reliability for curve types (kappa = 0.64), regional sagittal modifiers (kappa = 0.73), and degenerative lumbar modifiers (kappa = 0.65) were substantial. Interobserver reliability was moderate (kappa = 0.56) for choosing a cephalad level for operative treatment and substantial for choosing a caudad level (kappa = 0.77). CONCLUSIONS: A uniform system for classification of adult spinal deformity has significant utility in improving the ability of surgeons and authors to compare and combine similar cases, and in improving the accuracy of reports on the outcomes of care for adults with spinal deformity. The SRS Classification System for Adult Spinal Deformity has good interobserver reliability and is predictive of surgical strategies. Further validation of the SRS Classification System will include measures of intraobserver reliability, and inclusion of clinical characteristics of patient presentation and comorbidities.

Adult↗
PubMed1997

The Revised European-American Classification of Lymphoid Neoplasms (REAL): a new perspective for the classification of cutaneous lymphomas.

Differing classification schemes for malignant lymphomas have been used in Europe and the United States. Attempts to translate between the principle classifications have been unsuccessful and historically it has been difficult to arrive at an unified approach. In addition, many new lymphoma entities have been recognized in recent years that are not delineated in any of the existing classification schemes. To provide a unified international basis for clinical and investigative work in this field, in 1994 the International Lymphoma Study Group (ILSG) proposed a new classification termed Revised European-American Classification of Lymphoid Neoplasms (REAL). This review discusses the REAL classification, especially as it pertains to cutaneous lymphomas, and provides insight into the clinicopathologic features of lymphoproliferative disease involving the skin. The premise of the REAL classification is that a classification scheme should be based on the delineation of disease entities, utilizing pathologic, immunophenotypic, genetic, and clinical features. Therefore, if cutaneous involvement is an integral aspect of any lymphoma subtype, this clinical information is included in the definition of that neoplasm. We conclude that the principles of the REAL classification are applicable to cutaneous lymphomas, as well as lymphomas involving other anatomic sites.

Humans↗
PubMed2002

The reliability of the pre-operative classification of open tibial fractures in children a proposal for a new classification.

The purpose of this observational study was to evaluate the accuracy of Gustilo's classification of open tibial fractures in children. Pre- and post-debridement (using the parameters of Gustilo's classification) wound gradings in 27 children with a mean age of 10 years (3 to 15 years) who had sustained an open tibial fracture were compared. Pre-operative Polaroid photographs of the wound were taken of all these patients in the accident and emergency department. In every case, the fracture was treated with prophylactic intravenous antibiotic administration, wound debridement and lavage. Following wound exploration in the operating theater, the wound was classified using Gustilo's parameters again; this was different from the initial grading. We compared post-debridement classification according to Gustilo to the new classification which we propose. The latter classification is a peroperative assessment of the extent of soft tissue damage and it addresses bone stability. According to this classification, the majority of open tibial fractures were stable, requiring no skin graft or flap and had a good outcome. Only five patients were treated by initial external fixation of the tibia; the remainder were treated by cast immobilization. Wounds were treated as appropriate. The clinical outcome study included the assessment of wound and fracture healing and the incidence of complications. The mean period for follow-up was 8 months (6 to 24 months). There were no cases of nonunion or deep wound infection and the wounds healed in all these patients. We conclude that Gustilo's classification is not specific and does not reflect the extent of soft tissue and skeletal damage. Factors such as the degree of soft tissue damage and periosteal stripping that are noticed following wound debridement and velocity of injury are far more important than the wound size. Our proposed peroperative classification covers the extent of soft tissue injury and skeletal stability, thus predicting the outcome more than the Gustilo classification.

Adolescent↗
PubMed1996

[The pT-classification of primary vocal cord carcinomas and its significance for T-classification].

Since the pretherapeutic T and pT classification of vocal cord cancer according to the UICC has often been found to fail in a high percentage of cases, frequently resulting in an insufficient separation of the different T categories, the pT classification proposed by Glanz was applied in order to obtain a more exact and better reproducible pretreatment system. In a histopathological investigation of 223 previously untreated carcinomas of the vocal cord dating from 1978 to 1988, specimens from total and partial laryngectomies were examined by subserial sectionings. The extension of each lesion was ascertained by measuring tumor in three dimensions per millimeter and determining affected histopathological structures. Neck lymph nodes were also examined for metastases. The different tumor stages were then evaluated with the UICC T/pT classification of Glanz's pT classification. The survival rates and recurrence-free rates of both classification systems were compared. Our evaluation showed that 24% of all the vocal cord cancers studied had to be classified to a higher tumor stage. The pT classification developed by Glanz was better able to separate the different tumor categories than the UICC T/pT classification. Glanz's pT classification system, staging a glottic cancer according to its exact size and laryngeal structures involved, is a significant improvement on the UICC T and pT classification used to date.

Adult↗
PubMed1997

[Prognostic value of histologic classifications of advanced stomach cancer: comparative study of Lauren's and Goseki's classifications].

Controversy exists about the prognostic value of the histological classifications of gastric cancer commonly used. Recently Goseki proposed a new classifying system based on intracellular mucus production and the degree of tubular differentiation. The aim of this study was to compare Lauren and Goseki classifications with particular emphasis on their prognostic significance. Eighty-nine patients, who underwent potentially curative resections (RO) and radical lymphadenectomy for advanced gastric cancer from September 1988 to April 1996 were analysed. Cox regression model was used to evaluate the prognostic significance of Goseki classification, Lauren classification, age, sex, type of lymphadenectomy, depth of tumour invasion (T), node metastases (N) and number of metastatic nodes. A statistically significant correlation between the different Goseki grades and histology according to Lauren was found (p < 0.001). By multivariate analysis the only parameters predictive of long term outcome were depth of tumour invasion, nodal status and histology according to the Lauren classification. Also after excluding the Lauren classification from the analysis, the Goseki histological grading system did not affect survival independently. This study on advanced gastric cancer patients identified depth of invasion, lymph node metastases and Lauren classification as significant independent pathological variables influencing survival. The classification proposed by Goseki did not add anything further to the prognostic informations provided by TNM staging and Lauren classification.

Adenocarcinoma↗
PubMedDate not supplied

Classification of 1H MR spectra of human brain neoplasms: the influence of preprocessing and computerized consensus diagnosis on classification accuracy.

We study how classification accuracy can be improved when both different data preprocessing methods and computerized consensus diagnosis (CCD) are applied to 1H magnetic resonance (MR) spectra of astrocytomas, meningiomas, and epileptic brain tissue. The MR spectra (360 MHz, 37 degrees C) of tissue specimens (biopsies) from subjects with meningiomas (95; 26 cases), astrocytomas (74; 26 cases), and epilepsy (37; 8 cases) were preprocessed by several methods. Each data set was partitioned into training and validation sets. Robust classification was carried out via linear discriminant analysis (LDA), artificial neural nets (NN), and CCD, and the results were compared with histopathological diagnosis of the MR specimens. Normalization of the relevant spectral regions affects classification accuracy significantly. The spectra-based average three-class classification accuracies of LDA and NN increased from 81.7% (unnormalized data sets) to 89.9% (normalized). CCD increased the classification accuracy of the normalized sets to an average of 91.8%. CCD invariably decreases the fraction of unclassifiable spectra. The same trends prevail, with improved results, for case-based classification. Preprocessing the 1H MR spectra is essential for accurate and reliable classification of astrocytomas, meningiomas, and nontumorous epileptic brain tissue. CCD improves classification accuracy, with an attendant decrease in the fraction of unclassifiable spectra or cases.

Astrocytoma↗
PubMed2005

Does Shamblin's classification predict postoperative morbidity in carotid body tumors? A proposal to modify Shamblin's classification.

The objective of this study was to analyze the possible correlation between Shamblin's classification and post-surgical morbidity in the treatment of carotid body tumors (CBTs). Seventy-two patients with carotid body tumors were seen over a 22-year period. Twenty-three patients were excluded as they did not comply with the criteria of the objectives. All patients were grouped according to Shamblin's classification. We propose a modification to this classification and make a comparison by analyzing the surgical time and bleeding, as well as the neurological and vascular damage. We resected 50 CBTs in 49 patients, ranging in age from 18 to 73 years. Three groups were formed: group I with 8 (16%) patients, group II with 17 (34%) and group III with 24 (49%). Post-surgical neurological damage was observed in one patient (12.5%) from group I, in six (35%) from group II and in nine patients (37.5%) from group III. Vascular sacrifice had to be performed in 21% of class II tumors and in 8.7% of class III. None of the class I tumors required vascular sacrifice. No statistically significant difference existed for vascular or neurological risk in relation to Shamblin's classification. However, when analyzed according to the classification proposed herein, there was a correlation between Shamblin's classification and vascular sacrifice (P =0.001). There was a statistically significant correlation between the original Shamblin and the modified Shamblin regarding surgical time and bleeding. Shamblin's classification predicts only vascular morbidity. Neurological morbidity is not reflected in it and only reflects the surgeon's experience with CBT resections. Surgical time and bleeding are directly related to the Shamblin as it reflects the size of tumors in relation to the blood vessels. Shamblin's classification must be modified to be more objective so that the international reports can accurately reflect the morbidity related to it.

Adolescent↗
PubMed2002

The Quebec classification and a new Swedish classification for whiplash-associated disorders in relation to life satisfaction in patients at high risk of chronic functional impairment and disability.

Unlike the Quebec classification system, which is based primarily on pathoanatomy, a new Swedish classification system is based on the site of functional impairment and disability. A prospective study was performed on 85 patients with whiplash-associated disorders grade II according to the Quebec classification. The patients were examined 3-36 months following trauma. A team of professionals with different training performed the diagnostic procedure. An independent assessor classified these patients according to a Swedish classification system. All patients answered questionnaire regarding life satisfaction. Logistic regression demonstrated significant differences in 6 of 10 specific dimensions of life satisfaction between the classification categories C and D (presence of arm symptoms) in a Swedish classification. Patients with whiplash-associated disorders grade II and neuropsychological symptoms seem to have a worse prognosis for spontaneous recovery than those without. A new Swedish classification system seems to be an important complement to the Quebec classification.

Absenteeism↗
PubMed2004

A comparative study of feature selection and multiclass classification methods for tissue classification based on gene expression.

This paper studies the problem of building multiclass classifiers for tissue classification based on gene expression. The recent development of microarray technologies has enabled biologists to quantify gene expression of tens of thousands of genes in a single experiment. Biologists have begun collecting gene expression for a large number of samples. One of the urgent issues in the use of microarray data is to develop methods for characterizing samples based on their gene expression. The most basic step in the research direction is binary sample classification, which has been studied extensively over the past few years. This paper investigates the next step-multiclass classification of samples based on gene expression. The characteristics of expression data (e.g. large number of genes with small sample size) makes the classification problem more challenging. The process of building multiclass classifiers is divided into two components: (i) selection of the features (i.e. genes) to be used for training and testing and (ii) selection of the classification method. This paper compares various feature selection methods as well as various state-of-the-art classification methods on various multiclass gene expression datasets. Our study indicates that multiclass classification problem is much more difficult than the binary one for the gene expression datasets. The difficulty lies in the fact that the data are of high dimensionality and that the sample size is small. The classification accuracy appears to degrade very rapidly as the number of classes increases. In particular, the accuracy was very low regardless of the choices of the methods for large-class datasets (e.g. NCI60 and GCM). While increasing the number of samples is a plausible solution to the problem of accuracy degradation, it is important to develop algorithms that are able to analyze effectively multiple-class expression data for these special datasets.

Algorithms↗
PubMed2000

[Evaluation of classification of pancreatic cancer by the Japan Pancreas Society and Union Internationale Contre le Cancer and proposal for a new international classification].

Different classification systems of pancreatic cancer by the Japan Pancreas Society (JPS, 1996) and Union Internationale Contre le Cancer (UICC) (1997), both of which are based on the TNM system, have been hampering the exchange of data between Japan and Western countries. In the present study, both classifications were assessed using data from 67 patients with invasive ductal carcinoma of the pancreatic head who underwent resection at our clinic. We also propose a new TNM classification and stage grouping system that draws on the merits of both. The results showed that UICC stage grouping did not reflect outcome well, while the JPS system predicted outcome much better. The prognostic value of tha T category is sufficiently reliable in both classifications, but the major drawback of the JPS system is its complex structure and difficult handling. To meet the ideal standard for an international classification system, we propose a new classification: the T category is a minor modification of that of the UICC, and the N category is a modification of that of the JPS for much simpler grouping. Based on the data from our 67 resected patients cases, our new staging system reflects the outcome in the four stages well. Our new classification system may improve the staging classification and lead to the establishment of a more practical and universal staging system for ductal carcinoma of the pancreas.

Humans↗
PubMed2000

[Malignant lymphoma: REAL classification to new WHO classification].

The Revised European-American Classification of Lymphoid Neoplasms(REAL) proposed in 1994 represented a new paradigm for the classification of lymphomas. This classification emphasized that each disease was a distinct entity, defined by a constellation of clinical and laboratory features, i.e., morphology and genetic features, immunophenotype, clinical presentation, and course. And it also noted that the site(s) of presentation were a signpost for important underlying biologic distinctions. A new WHO classification is planed to be proposed, re-categorizing entities of the REAL classification. Now, WHO members planed to publish the new classification as the bluebook of WHO at first in 1998 and now in 2000. This paper reports mainly different points in the new WHO classification of malignant lymphoma from the REAL classification.

B-Lymphocytes↗