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PubMed1999

The World Health Organization classification of neoplastic diseases of the hematopoietic and lymphoid tissues. Report of the Clinical Advisory Committee meeting, Airlie House, Virginia, November, 1997.

INTRODUCTION: Since 1995, the European Association of Pathologists (EAHP) and the Society for Hematopathology (SH) have been developing a new World Health Organization (WHO) Classification of hematologic malignancies. The classification includes lymphoid, myeloid, histiocytic, and mast cell neoplasms. DESIGN: The WHO project involves 10 committees of pathologists, who have developed lists and definitions of disease entities. A Clinical Advisory Committee (CAC)) of international hematologists and oncologists was formed to ensure that the classification will be useful to clinicians. A meeting was held in November, 1997, to discuss clinical issues related to the classification. RESULTS: The WHO has adopted the 'Revised European American Classification of Lymphoid Neoplasms' (R.E.A.L.), published in 1994 by the International Lymphoma Study Group (ILSG), as the classification of lymphoid neoplasms. This approach to classification is based on the principle that a classification is a list of 'real' disease entities, which are defined by a combination of morphology, immunophenotype, genetic features, and clinical features. The relative importance of each of these features varies among diseases, and there is no one 'gold standard'. The WHO Classification has applied the principles of the R.E.A.L. Classification to myeloid and histiocytic neoplasms. The classification of myeloid neoplasms recognizes distinct entities defined by a combination of morphology and cytogenetic abnormalities. The CAC meeting, which was organized around a series of clinical questions, was able to reach a consensus on most of the questions posed. The questions and the consensus are discussed in detail below. Among other things, the CAC concluded that clinical groupings of lymphoid neoplasms were neither necessary nor desirable. Patient treatment is determined by the specific type of lymphoma, with the addition of grade within the tumor type, if applicable, and clinical prognostic factors such as the international prognostic index (IPI). CONCLUSION: The experience of developing the WHO Classification has produced a new and exciting degree of cooperation and communication between oncologists and pathologists from around the world, which should facilitate progress in the understanding and treatment of hematologic malignancies.

Hematologic Neoplasms↗

PubMed2000

The World Health Organization classification of hematological malignancies report of the Clinical Advisory Committee Meeting, Airlie House, Virginia, November 1997.

Since 1995, the European Association of Pathologists and the Society for Hematopathology have been developing a new World Health Organization (WHO) classification of hematologic malignancies. The classification includes lymphoid, myeloid, histiocytic, and mast cell neoplasms. The WHO project involves 10 committees of pathologists, who have developed lists and definitions of disease entities. A Clinical Advisory Committee of international hematologists and oncologists was formed to ensure that the classification will be useful to clinicians. A meeting was held in November 1997 to discuss clinical issues related to the classification. The WHO has adopted the Revised European-American Classification of Lymphoid Neoplasms, published in 1994 by the International Lymphoma Study Group, as the classification of lymphoid neoplasms. This approach to classification is based on the principle that a classification is a list of "real" disease entities, which are defined by a combination of morphology, immunophenotype, genetic features, and clinical features. The relative importance of each of these features varies among diseases, and there is no one "gold standard." The WHO classification has applied the principles of the Revised European-American Classification of Lymphoid Neoplasms to myeloid and histiocytic neoplasms. The classification of myeloid neoplasms recognizes distinct entities defined by a combination of morphology and cytogenetic abnormalities. The Clinical Advisory Committee meeting, which was organized around a series of clinical questions, was able to reach a consensus on most of the questions posed. The questions and the consensus are discussed in detail in this article. Among other things, the Clinical Advisory Committee concluded that clinical grouping of lymphoid neoplasms was neither necessary nor desirable. Patient treatment is determined by the specific type of lymphoma, with the addition of grade within the tumor type, if applicable, and clinical prognostic factors such as the international prognostic index. The experience of developing the WHO classification has produced a new and exciting degree of cooperation and communication between oncologists and pathologists from around the world. This should facilitate progress in the understanding and treatment of hematologic malignancies.

Hematologic Neoplasms↗

PubMed2000

The World Health Organization classification of neoplasms of the hematopoietic and lymphoid tissues: report of the Clinical Advisory Committee meeting--Airlie House, Virginia, November, 1997.

INTRODUCTION: Since 1995, the European Association of Pathologists and the Society for Hematopathology have been developing a new World Health Organization (WHO) classification of hematologic malignancies. The classification includes lymphoid, myeloid, histiocytic, and mast cell neoplasms. MATERIALS AND METHODS: The WHO project involves ten committees of pathologists, who have developed lists and definitions of disease entities. A Clinical Advisory Committee (CAC) of international hematologists and oncologists was formed to ensure that the classification will be useful to clinicians. A meeting was held in November 1997 to discuss clinical issues related to the classification. RESULTS: WHO has adopted the 'Revised European-American Classification of Lymphoid Neoplasms' (REAL), published in 1994 by the International Lymphoma Study Group (ILSG), as the classification of lymphoid neoplasms. This approach to classification is based on the principle that a classification is a list of 'real' disease entities, which are defined by a combination of morphology, immunophenotype, genetic features, and clinical features. The relative importance of each of these features varies among diseases, and there is no one 'gold standard'. The WHO classification has applied the principles of the REAL classification to myeloid and histiocytic neoplasms. The classification of myeloid neoplasms recognizes distinct entities defined by a combination of morphology and cytogenetic abnormalities. The CAC meeting, which was organized around a series of clinical questions, was able to reach a consensus on most of the questions posed. The questions and the consensus are discussed in detail below. Among other things, the CAC concluded that clinical groupings of lymphoid neoplasms were neither necessary nor desirable. Patient treatment is determined by the specific type of lymphoma, with the addition of grade within the tumor type, if applicable, and clinical prognostic factors such as the international prognostic index (IPI). CONCLUSION: The experience of developing the WHO classification has produced a new and exciting degree of cooperation and communication between oncologists and pathologists from around the world, which should facilitate progress in the understanding and treatment of hematologic malignancies.

Hematologic Neoplasms↗

PubMed2000

The World Health Organization classification of neoplastic diseases of the haematopoietic and lymphoid tissues: Report of the Clinical Advisory Committee Meeting, Airlie House, Virginia, November 1997.

INTRODUCTION: Since 1995, the European Association of Pathologists (EAHP) and the Society for Hematopathology (SH) have been developing a new World Health Organization (WHO) classification of haematological malignancies. The classification includes lymphoid, myeloid, histiocytic and mast cell neoplasms. DESIGN: The WHO project involves 10 committees of pathologists, who have developed lists and definitions of disease entities. A Clinical Advisory Committee (CAC) of international haematologists and oncologists was formed to ensure that the classification will be useful to clinicians. A meeting was held in November 1997 to discuss clinical issues related to the classification. RESULTS: The WHO has adopted the 'Revised European-American Classification of Lymphoid Neoplasms' (REAL), published in 1994 by the International Lymphoma Study Group (ILSG), as the classification of lymphoid neoplasms. This approach to classification is based on the principle that a classification is a list of 'real' disease entities, which are defined by a combination of morphology, immunophenotype, genetic features and clinical features. The relative importance of each of these features varies among diseases, and there is no one 'gold standard'. The WHO classification has applied the principles of the REAL classification to myeloid and histiocytic neoplasms. The classification of myeloid neoplasms recognizes distinct entities defined by a combination of morphology and cytogenetic abnormalities. The CAC meeting, which was organized around a series of clinical questions, was able to reach a consensus on most of the questions posed. The questions and the consensus are discussed in detail below. Among other things, the CAC concluded that clinical groupings of lymphoid neoplasms was neither necessary nor desirable. Patient treatment is determined by the specific type of lymphoma, with the addition of grade within the tumour type, if applicable, and clinical prognostic factors such as the international prognostic index (IPI). CONCLUSION: The experience of developing the WHO classification has produced a new and exciting degree of cooperation and communication between oncologists and pathologists from around the world, which should facilitate progress in the understanding and treatment of haematological malignancies.

Hematologic Neoplasms↗

PubMed2001

False-positive reduction in CAD mass detection using a competitive classification strategy.

High false-positive (FP) rate remains to be one of the major problems to be solved in CAD study because too many false-positively cued signals will potentially degrade the performance of detecting true-positive regions and increase the call-back rate in CAD environment. In this paper, we proposed a novel classification method for FP reduction, where the conventional "hard" decision classifier is cascaded with a "soft" decision classification with the objective to reduce false-positives in the cases with multiple FPs retained after the "hard" decision classification. The "soft" classification takes a competitive classification strategy in which only the "best" ones are selected from the pre-classified suspicious regions as the true mass in each case. A neural network structure is designed to implement the proposed competitive classification. Comparative studies of FP reduction on a database of 79 images by a "hard" decision classification and a combined "hard"-"soft" classification method demonstrated the efficiency of the proposed classification strategy. For example, for the high FP sub-database which has only 31.7% of total images but accounts for 63.5% of whole FPs generated in single "hard" classification, the FPs can be reduced for 56% (from 8.36 to 3.72 per image) by using the proposed method at the cost of 1% TP loss (from 69% to 68%) in whole database, while it can only be reduced for 27% (from 8.36 to 6.08 per image) by simply increasing the threshold of "hard" classifier with a cost of TP loss as high as 14% (from 69% to 55%). On the average in whole database, the FP reduction by hybrid "hard"-"soft" classification is 1.58 per image as compared to 1.11 by "hard" classification at the TP costs described above. Because the cases with high dense tissue are of higher risk of cancer incidence and false-negative detection in mammogram screening, and usually generate more FPs in CAD detection, the method proposed in this paper will be very helpful in improving the performance of early detection of breast cancer with CAD.

Biophysical Phenomena↗

PubMed2005

Prognostic value of the 2002 TNM classification for breast carcinoma with regard to the number of metastatic axillary lymph nodes.

BACKGROUND: The American Joint Committee on Cancer (AJCC) TNM classification for breast carcinoma had not been changed for 15 years, since the publication of the third edition in 1987. However, in the sixth edition, published in 2002, significant modifications were made with regard to the number of metastatic axillary lymph nodes. The authors investigated whether the sixth edition of the TNM classification provided more reliable prognostic information compared with the third edition. METHODS: The records of 1230 patients who underwent surgery for invasive breast carcinoma between 1993 and 1999 were reviewed. Each patient was assigned to axillary lymph node and disease stage groups according to the 1987 and 2002 AJCC TNM classifications. Disease-free survival (DFS) curves were calculated and plotted using the Kaplan-Meier method and the two-sided log-rank test was used to compare the survival curves of the patient groups. RESULTS: Of the 1067 patients who were classified as having Stages II and III disease according to the 1987 classification, 411 (38.5%) were shifted to higher disease stages using the 2002 classification. Among the 1987 Stage IIA, Stage IIB, and Stage IIIA patients, the DFS rates of the patients who were shifted to higher stages of disease were significantly worse than those of the patients for whom the stage of disease was not changed. Among those patients classified as having T4anyNM0 (Stage IIIB) disease according to the 1987 classification, there was no survival difference noted between those patients with T4N0,1,2M0 disease (who formed the Stage IIIB group) and those with T4N3M0 disease (who formed the Stage IIIC group) according to the new staging system. Of the 221 patients who formed the new Stage IIIC group, 12.2% were classified as having Stage IIA disease, 42.1% as having Stage IIB disease, 38.9% as having Stage IIIA disease, and 6.8% as having Stage IIIB disease according to the 1987 classification. The survival rates of these Stage IIA, Stage IIB, and Stage IIIA patients were not found to be significantly different; however, the survival of patients in the Stage IIIB group was found to be significantly worse than the survival of the patients in the other disease stage groupings, and the patients in the Stage IIIC group were not a prognostically homogeneous group. On the basis of these results, the authors placed patients with T4anyNM0 disease in the same group (Stage IIIB). When the 2002 classification was rearranged in this manner, patients with Stage IIIC disease formed a homogeneous group; the 5-year DFS rate of patients with Stage IIIB disease was found to be significantly worse than that for patients with Stage IIIC disease (P = 0.0011). CONCLUSIONS: In the 2002 TNM classification for breast carcinoma, patients with T4anyNM0 disease should form a distinct stage grouping and this stage grouping (Stage IIIC) should be placed before Stage IV, and Stage IIIB disease groupings should include patients with T1,2,3N3M0 disease. In this way, the authors hope that the 2002 AJCC TNM classification, which provides more reliable prognostic information than the 1987 classification, will become more refined.

Breast Neoplasms↗

PubMed2000

A simplified lesion classification for predicting success and complications of coronary angioplasty. Registry Committee of the Society for Cardiac Angiography and Intervention.

In 1988, the American College of Cardiology/American Heart Association (ACC/AHA) Task Force on Assessment of Diagnostic and Therapeutic Cardiovascular Procedures presented a classification of coronary lesions utilizing 26 lesion features to predict the success and complications of balloon angioplasty. Using data from the Registry of the Society for Cardiac Angiography and Interventions (SCAI) we evaluated the ability of this classification to predict success and complications. Lesion success, death in hospital, emergency cardiac bypass surgery, and major adverse events were evaluated in 41,071 patients who underwent single-vessel angioplasty from January 1993 to June 1996. Logistic models using the ACC/AHA lesion classification, vessel patency, or both, were compared. A new classification based on the interaction of the ACC/AHA classification plus lesion patency was compared with the existing ACC/AHA classification. Vessel patency, added to the ACC/AHA classification, improved prediction of lesion success (p </=0.0001). Class A and patent B lesions had similar success and complication rates, so a simplified classification (SCAI) using only 7 lesion characteristics could be created. This system (I: non-C patent, II: C patent, III: non-C occluded, and IV: C occluded) improved prediction of lesion success compared with the ACC/AHA classification (Bayesian Information Criterion statistic: ACC/AHA 16539, SCAI 15956; and area under the receiver- operating characteristics curve 0.659, 0.693, respectively). The SCAI classification was preferred for predicting major complications and in-hospital death and was similar to the ACC/AHA classification for predicting emergency bypass surgery.

Aged↗

PubMed1998

Measuring the unmeasurable: a caring science perspective on patient classification.

AIMS: To give a short historical survey of patient classification and its motives, to analyse patient classification and especially the instrument, The Oulu Patient Classification more closely from a caring science perspective. BACKGROUND: A survey of topical literature and research on patient classification show that economic and administrative justifications predominate and the caring science connection is weak, almost non-existent. ORIGINS OF INFORMATION: Topical literature and research on patient classification and the instrument, The Oulu Patient Classification. DATA ANALYSIS: Topical literature and research were evaluated from a caring science perspective in accordance with Eriksson's theory of caring and the basic concept of man as an entity of body, soul and spirit. KEY ISSUES: Patient classification is used in staff planning and is also justified from the viewpoint of content, that is, as a method of guaranteeing good quality in the care of patients and as an expression of the prevalent caring ideology. The concept of man is reduced in current literature and research on patient classification. The Oulu Patient Classification is based on a humanistic view of man, but man's spiritual and existential needs do not emerge clearly from the manual of the instrument. CONCLUSIONS: It is essential for patient classification to start from a caring perspective. Correctly dimensioned staffing based on patient classification is a prerequisite for good care. This should be combined with a caring culture that considers the whole complexity of man in order to make good care possible.

Activities of Daily Living↗

PubMed2002

[Pigment epithelial detachments in age-related macular degeneration -- classification, differentiation and prognosis].

BACKGROUND: A pigment epithelial detachment (PED) is an exudative manifestation of late age-related macular degeneration (AMD). Its long-term unfavourable prognosis is influenced by the association of a neovascular membrane. Seemingly identical PEDs in ophthalmoscopy can be further differentiated by fluorescein and indocyanine green angiography. The purpose of this prospective follow-up study was to determine the most reliable angiographic classification to distinguish PEDs in AMD and to evaluate their outcome. MATERIAL AND METHODS: 73 eyes of 68 patients with a PED in AMD were examined with simultaneous angiography with fluorescein and indocyanine green. 34 eyes were additionally scanned by retinatomography. Fluorescein angiographic classification comprises 4 types: 1. early hyperfluorescent type, 2. late hyperfluorescent type, 3. drusen type, 4. irregular fluorescent type. Indocyanine green angiographic classification consists of the following three groups: 1. angiographically no vascularisation, 2. associated choroidal neovascularisation, 3. associated polypoidal choroidal vasculopathy. RESULTS: Both classifications show statistically significant correlation with visual acuity (fluorescein classification: P = 0.0112, ICG-classification: P = 0.0004) and area of the PEDs (fluorescein classification: P = 0.0002, ICG-classification: P < 0.0001). ICG-classification additionally is significantly associated with the volume (P = 0.0008). Both classifications correlate (P = 0.0001). Factors influencing visual acuity are: age (P = 0.0044), associated neovascular membrane (P = 0.0004), area (P < 0.0001), volume (P = 0.0077) and height (P < 0.0001). CONCLUSIONS: PEDs in AMD can best be classified by indocyanine green angiography on the basis of an associated prognostically important neovascular membrane, which can only be further distinguished into choroidal neovascularisation or polypoidal choroidal vasculopathy by indocyanine green angiography. Statistical analysis shows qualitatively and quantitatively more significant results for the indocyanine green angiographic classification.

Aged↗

PubMed2001

Reliability of a stool consistency classification system.

PURPOSE: Reliability and validity are important measures of the quality of a research or clinical instrument. This research determined the inter-rater and test-retest reliability of a stool consistency classification system and the agreement between the subjects' and expert investigators' classifications. METHODS: Two studies were conducted with adult volunteers. Stool consistency was described by words only and words + diagrams. To determine inter-rater reliability, subjects in each of 3 groups (20 nurses, 20 nursing students, and 20 lay persons) classified the consistency of 12 stool specimens. To determine test-retest reliability, 43 additional subjects classified the consistency of 9 stool specimens in 2 sessions. OUTCOME MEASURES: Outcome measures were reported per individual stool specimen and for all stool specimens. The outcome measures were the consistency classifications by the 3 groups of raters when the 2 types of descriptors (word only and word + diagram) were used. Other outcomes were the consistency classifications of the subjects on the 2 days of stool evaluation and the classifications of the subjects compared with those of the investigators. RESULTS: No significant difference was found among the stool consistency classifications among nurses, nursing students, or lay persons. Classifications were similar for 11 of 12 stool specimens when either word-only or word + diagram descriptions were used. No significant difference was found among the classifications between days 1 and 2. At least 75% of the subjects' classifications of stool consistency in both studies agreed highly with those of the investigators. CONCLUSIONS: The reliability and validity of the stool consistency classification system are good. The word-only descriptions of the consistency classifications appeared to be equally as effective as the word + diagram descriptions.

Adult↗

PubMed1993

Validation of surgical wound classification in the operating room.

OBJECTIVE: To determine the accuracy with which circulating nurses (CNs) classify surgical procedures by risk of contamination in the operating room. DESIGN: Classification of surgical procedures by CNs was compared with the classification of surgical procedures by a physician observer. SETTING: University-affiliated, tertiary care hospital. METHODS: Circulating nurses used the traditional wound classification system of clean, clean-contaminated, contaminated, and dirty-infected to classify surgical wounds in the operating room. A physician remained in the operating room throughout each of 100 surgical procedures and simultaneously classified surgical wounds without the knowledge of the CNs. RESULTS: Classification of surgical wounds by CNs was compared with classification by the physician observer for 50 cases in general surgery and 50 cases in trauma surgery. Compared with the physician observer, the overall accuracy of classification by CNs was 88% (95% confidence interval [CI] of 81.6% to 94.4%; Kappa statistic, 0.83). Classification of surgical wounds was more difficult in trauma surgery (accuracy of 82%) than in general surgery (accuracy of 94%). Accuracy increased for both services when surgical wounds were classified into just two categories (clean or clean-contaminated versus contaminated or dirty-infected). CONCLUSIONS: Surgical wounds can be classified in the operating room with a high degree of accuracy by CNs. Classification was more difficult in trauma than in general surgery, but classification in trauma surgery improved with feedback to and additional education of CNs. The accuracy of classification by CNs was even higher when classifications were divided into just two categories.

Hospital Bed Capacity, 300 to 499↗

PubMed2001

Multisurgeon assessment of surgical decision-making in adolescent idiopathic scoliosis: curve classification, operative approach, and fusion levels.

STUDY DESIGN: A multisurgeon assessment of curve classification, selection of operative approach, and fusion levels via a case study presentation. OBJECTIVES: To evaluate the ability of a group of scoliosis surgeons, not involved in the development of a new classification system, to accurately choose the corresponding curve classification of adolescent idiopathic scoliosis (AIS) cases and to evaluate the variability in the selection of operative approaches and both proximal and distal fusion levels in accordance with the new classification system in operative adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Recent evaluations using the King method for classifying AIS has shown poor intraobserver and interobserver reliability. A new, comprehensive classification system of AIS has been developed, but the result of a scoliosis surgeon's ability to apply the objective classification is unknown. In the surgical treatment of AIS, there are three choices for the operative approach (anterior, posterior, or both) and multiple choices for the selection of fusion levels. METHODS: During an AIS roundtable discussion at a spinal surgery meeting, 28 scoliosis surgeons were presented seven cases of operative AIS via good quality slides. Standard preoperative radiographs and clinical photographs were presented, and the reviewers were asked to classify the cases by a new classification system, choose their preferred surgical approach, and classify both proximal and distal fusion levels. RESULTS: For the seven cases presented, 84% of the curve types, 86% of lumbar modifiers, and 90% of sagittal thoracic modifiers were classified by the reviewers as described in the new classification. The case study found widely variable operative approaches and fusion levels chosen by the reviewers. There was an average of five different proximal (range, 4-8) and four different distal (range, 3-5) fusion levels chosen by the reviewers for each case. CONCLUSIONS: This case study assessment found a relatively high rate (84-90%) of agreement in curve classification of the individual components of a new classification system of AIS. This suggests the ability of a group of scoliosis surgeons to identify the specific criteria necessary for this new classification system of AIS. In addition, the high variability in selection of both operative approach and fusion levels confirms the current lack of standardized treatment paradigms. This further reinforces the need for a method to critically and objectively evaluate these variable treatments to determine the "best" radiographic and clinical results.

Adolescent↗

PubMed1998

Classifications of the International League Against Epilepsy: time for reappraisal.

Recent advances in neurodiagnostic technology, new insights into fundamental neuronal mechanisms of epilepsy, and rapid developments in molecular genetics have greatly improved our understanding of epileptic seizures and epileptic disorders since 1981, when the current International Classification of Epileptic Seizures was adopted, and since 1989, when the International Classification of Epilepsies, Epileptic Syndromes, and Related Disorders was adopted. Although both have been universally accepted and have proven to be of considerable clinical value, it has become clear that more is needed for specific applications of growing importance, such as presurgical evaluation, clinical pharmacology trials, and epidemiological studies. Therefore, an International League Against Epilepsy (ILAE) task force has evaluated the need for revising our current classification and terminology and has begun developing four specific documents. The first is a descriptive terminology for ictal phenomena, incorporating some of the concepts included in the preceding paper by Dr. Hans Lüders; however, this will be a glossary, not a classification. The second is a classification of epileptic seizures based on known or presumed pathophysiological and anatomic substrates, to replace the current classification, which is based entirely on phenomenology. The third is a classification of epileptic syndromes and epileptic diseases, adapted from the current Classification of Epilepsies, Epileptic Syndromes, and Related Disorders, which will take into account the fact that disorders with unique etiologies, such as a single gene, should be considered diseases, and which will be reorganized for maximum practical application to differential diagnosis. The fourth is a new classification of functional disability due to seizures or epilepsy, based on a new impairment classification for neurological disorders being developed by the World Health Organization. Working groups are currently in the process of developing each of these documents, and their chairs would benefit from any comments or suggestions from those who ultimately will be using these systems of classification and terminology.

Epilepsy↗

PubMed2002

Classification of malignant lymphoma.

Over the past 30 years different lymphoma classifications were used world-wide. In Europe, the Kiel classification of K. Lennert dominated the scene, it was updated 1988 and 1992. In North America the Working Formulation, primarily designed to be an instrument for translation of one classification into the other, was predominantly used. Both classifications, however, showed little correspondence with each other, which made it difficult to compare the results of randomized clinical trials on both sides of the Atlantic Ocean. In 1994 the Revised European American Lymphoma (R.E.A.L.) classification was proposed by the International Lymphomas Study Group (ILSG). In contrast to the existing classifications it abandoned the grading of malignancies. The ILSG focused on diagnostic reproducibility and on the definition of distinct clinical-pathological lymphoma entities. Similar to the Kiel classification the new classification scheme was based on cell lineage (T- and B-cell origin) and cell differentiation (precursor and mature lymphomas) and included a number of distinct extranodal lymphomas. The new WHO classification is basically identical with the R.E.A.L. scheme and exhibits only minor changes. The WHO classification includes all hematopoietic and lymphoid neoplasms. It represents the first generally accepted classification, providing hematologists and oncologists with a solid diagnostic basis for therapeutic decisions.

Europe↗

PubMed2005

Modern classification of neoplasms: reconciling differences between morphologic and molecular approaches.

BACKGROUND: For over 150 years, pathologists have relied on histomorphology to classify and diagnose neoplasms. Their success has been stunning, permitting the accurate diagnosis of thousands of different types of neoplasms using only a microscope and a trained eye. In the past two decades, cancer genomics has challenged the supremacy of histomorphology by identifying genetic alterations shared by morphologically diverse tumors and by finding genetic features that distinguish subgroups of morphologically homogeneous tumors. DISCUSSION: The Developmental Lineage Classification and Taxonomy of Neoplasms groups neoplasms by their embryologic origin. The putative value of this classification is based on the expectation that tumors of a common developmental lineage will share common metabolic pathways and common responses to drugs that target these pathways. The purpose of this manuscript is to show that grouping tumors according to their developmental lineage can reconcile certain fundamental discrepancies resulting from morphologic and molecular approaches to neoplasm classification. In this study, six issues in tumor classification are described that exemplify the growing rift between morphologic and molecular approaches to tumor classification: 1) the morphologic separation between epithelial and non-epithelial tumors; 2) the grouping of tumors based on shared cellular functions; 3) the distinction between germ cell tumors and pluripotent tumors of non-germ cell origin; 4) the distinction between tumors that have lost their differentiation and tumors that arise from uncommitted stem cells; 5) the molecular properties shared by morphologically disparate tumors that have a common developmental lineage, and 6) the problem of re-classifying morphologically identical but clinically distinct subsets of tumors. The discussion of these issues in the context of describing different methods of tumor classification is intended to underscore the clinical value of a robust tumor classification. SUMMARY: A classification of neoplasms should guide the rational design and selection of a new generation of cancer medications targeted to metabolic pathways. Without a scientifically sound neoplasm classification, biological measurements on individual tumor samples cannot be generalized to class-related tumors, and constitutive properties common to a class of tumors cannot be distinguished from uninformative data in complex and chaotic biological systems. This paper discusses the importance of biological classification and examines several different approaches to the specific problem of tumor classification.

Cell Differentiation↗

PubMed1989

A comparative study of the JJC, AJC and UICC T classifications of squamous cell carcinoma of the maxillary sinus.

Seventy-six cases with squamous cell carcinoma of the maxillary sinus were treated with radiotherapy and surgery with or without intra arterial infusion between 1969 to 1985 at the Tokyo Women's Medical College. T classification was made of all cases using the Japan Joint Committee (JJC, 1967), American Joint Committee (AJC, 1977) and Union Internationale Contre le Cancer (UICC, 1987) classifications. 1) By the JJC classification, there were 20 cases in T2, 44 in T3 and 12 in T4. By the AJC classification, there were 9 cases in T2, 58 in T3 and 9 in T4. The classification of 14 cases were changed from JJC T2 to AJC T3, because of extension to the medial nasal meatus. By the UICC classification, there were 27 T2 cases, 32 T3 and 17 T4. 2) Cervical lymph node metastasis was detected in 14 cases (18%) at initial diagnosis and most were found in T3 and T4 cases. 3) The cumulative 5-year survival rates were 67% for T2, 32% for T3 and 25% for T4 by the JJC classification and statistical differences (p less than 0.05) were seen in T2-T3 and T2-T4. In the AJC classification, these were 71% for T2, 37% for T3 and 22% for T4 and no statistical significance was found among them. By the UICC classification, the 5-year survival was 58% for T2, 26% for T3 and 38% for T4 and marked statistical significance (p less than 0.01) was seen in T2-T3 and T2-T4. 4) The cumulative 5-year survival rate in 14 patients with tumor extension to the medial nasal meatus was 55% and it is appropriate to define this stage as T2 in the new UICC classification. These data suggested that UICC classification (1987) is useful and correlated with prognostic analysis.

Adult↗

PubMed1997

[Endoscopic classification of reflux esophagitis and its new developments].

Endoscopic diagnosis and classification of reflux esophagitis were described, which is gradually increasing in number in Japan. It is important to diagnosefor a type, grade, and degree, hearing stage and others (stenosis, Barrett's esophagus etc), when we perform endoscopic examination for reflux esophagitis patients. Iodine staining should be applied as far as possible. Los Angeles system for classification of reflux esophagitis was proposed at the 10th World Congress of Gastroenterology in October 1994. As for LA classification, reflux esophagitis is classified to 4 grade, from A to D, predicated on the grade of mucosal break. For any doctors, this is easy to apply to the classification of reflux esophagitis and the diagnosis of classification will be equal. The Japanese Society of Disease of Esophagus also proposed the new classification of reflux esophagitis, that is JSED '96 Classification. This classification contains grade 0, which indicate no reflux esophagitis and grade 1, which indicate the discoloring type of esophagitis. Another 3 grades are based on the length of esophagitis and also occupation on circumference of esophagus. This will be suitable for the Japanese reflux esophagitis and can be changed to LA classification easily. The International Society of Disease of Esophagus proposed AFP classification which is useful to decide the application to surgical treatment. The detail of these classifications and the important points on the endoscopic diagnosis of reflux esophagitis were mentioned in this paper.

Esophagitis, Peptic↗

PubMed1998

[R.E.A.L. classification of non-Hodgkin lymphoma from the clinico-oncologic viewpoint].

In 1994 the International Lymphoma Study Group (ILSG) published the "Revised European-American Classification of Lymphoid Neoplasms" (R.E.A.L. Classification). Lymphomas were classified according to their presumed normal counterparts, to the extent possible. Within both T- and B-cell categories differentiation between lymphomas and/or leukemias of "precursor" or "peripheral" neoplasms are defined arising from antigen independend or antigen reactive cell proliferation. Lymphomas undoubtedly characterized by currently available morphologic, immunologic, and genetic technics represent "real" disease entities. Provisional categories include lymphomas that have been described in some detail, but without consensus within the ILSG. Proposed names are based predominantly on established usage. With respect to similar treatment approaches and difficulties of the ILSG members in subclassifying large cell lymphomas, centroblastic, immunoblastic and large cell anaplastic lymphomas of B-cell type were "lumped" together as large B-cell lymphomas. Within a prospective treatment trial overall survival was significantly better in centroblastic as compared to B-cell immunoblastic lymphoma diagnosed by optimal histomorphology according the criteria of the Kiel Classification. Thus the R.E.A.L. Classification fails to identify patients who may require other than standard treatment. Future studies will demonstrate whether subclassifying the proposed "peripheral" T-cell lymphomas, unspecified into T-zone lymphoma, lymphoepitheloid (Lennert's) lymphoma and pleomorphic, small, medium, and large cell lymphomas according the Kiel Classification is of clinicopathologic relevance. On the contrary the subtypes of chronic lymphocytic leukemia of T-cell type form two distinct entities within the R.E.A.L. Classification separating T-CLL/prolymphocytic leukemia from large granular lymphocyte leukemia of T- and NK-cell type. Within the R.E.A.L. Classification the lymphoplasmacytoid immunocytoma of the Kiel Classification will be subsumed together with the prognostically significantly better B-cell chronic lymphocytic leukemia. Opposite to the original intention of the ILSG two proposals are developed on clinical grouping of entities. Clinical indolent lymphoid neoplasms usually have "low grade" histologic appearances, with a predominance of small cells subsuming with the exception of the mantle cell lymphoma all of the low grade lymphomas of the Kiel classification. Aggressive lymphomas (intermediate risk) are defined as tumors whose survival if untreated is measured in months, highly or very aggressive lymphomas and/or leukemias will kill untreated patients within weeks. Unlike the Kiel Classification proposed categories subsume lymphomas irrespective of cytomorphology, thus grouping together potentially curable and uncurable diseases. Undoubtedly the R.E.A.L. Classification forms at present the best compilation of existing knowledge upon neoplasms of the immune system, enabling cooperation between clinicians and scientists all over the world. According to the ILSG this proposal should be considered a starting point for future periodic reevaluations.

Europe↗