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Histologic Classification (histologic + classification)

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Medical Sciences	100%

Selected Abstracts

Histologic classification of ductal carcinoma in situ

MICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2002
Shabnam Jaffer
Abstract Prior to the current mammographic era, ductal carcinoma in situ (DCIS) usually presented as a large mass, was classified morphologically by architecture, and treated by mastectomy. The introduction of screening mammography led to an increase in the incidence of DCIS, a decrease in the average size of DCIS, and an increased emphasis on its heterogeneous nature. Thus, a reproducible and prognostically relevant classification system for DCIS is necessary. The ultimate goal of this classification is proper selection of patients for whom lumpectomy would suffice rather than mastectomy. Features to evaluate include: extent and size of disease, adequacy of resection margins, and histology. While none of the proposed histological classification systems were endorsed at the recent Consensus Conference on the Classification of DCIS, nuclear grade was the most important feature common to most of them. Architecture was given secondary importance. By definition, DCIS is a non-invasive clonal proliferation of epithelial cells originating in the terminal duct lobular unit, which would be expected to be monomorphic; however, it is the degree of nuclear pleomorphism that is primarily used to separate DCIS into low, intermediate, and high grades. Architecturally, DCIS has been divided into the following types: comedo, solid, cribriform, micropapillary, and papillary. Different architectural patterns and grades may be present in a given particular case; however, some combinations of patterns occur more frequently than others. Interobserver studies have shown nuclear grading to be interpreted with greater consistency than architecture, and nuclear grading methods have correlated with biological and molecular marker studies. Microsc. Res. Tech. 59:92,101, 2002. © 2002 Wiley-Liss, Inc. [source]

The World Health Organization histologic classification system reflects the oncologic behavior of thymoma,

CANCER, Issue 3 2002
A clinical study of 273 patients
Abstract BACKGROUND Although the histologic classification of thymic epithelial tumors has been confusing and controversial, an agreement on the universal classification system for thymic epithelial tumors was achieved by the World Health Organization (WHO) in 1999. The authors previously reported that the WHO histologic classification system reflects invasiveness and immunologic function of thymic epithelial tumors. In this subsequent study, they examined the prognostic significance of this classification system. METHODS Clinical features as well as postoperative survival of patients with thymoma, but not thymic carcinoma, were examined with reference to WHO histologic classification based on an experience with 273 patients over a 44-year period. RESULTS There were 18 type A tumors, 77 type AB tumors, 55 type B1 tumors, 97 type B2 tumors, and 26 type B3 tumors. In patients with type A, AB, B1, B2, and B3 tumors, the respective proportions of invasive tumor were 11.1%, 41.6%, 47.3%, 69.1%, and 84.6%; the respective proportions of tumors with involvement of the great vessels were 0%, 3.9%, 7.3%, 17.5%, and 19.2%; and the respective 20-year survival rates were 100%, 87%, 91%, 59%, and 36%. According to the Masaoka staging system, the 20-year survival rates were 89%, 91%, 49%, 0%, and 0% in patients with Stage I, II, III, IVa, and IVb disease, respectively. By multivariate analysis, the Masaoka staging system and the WHO histologic classification system were significant independent prognostic factors, whereas age, gender, association with myasthenia gravis, completeness of resection, or involvement of the great vessels were not significant independent prognostic factors. CONCLUSIONS This study showed that histologic appearance reflects the oncologic behavior of thymoma when the WHO classification system is adopted. The WHO classification system may be helpful in clinical practice for the assessment and treatment of patients with thymoma. Cancer 2002;94:624,32. © 2002 American Cancer Society. DOI 10.1002/cncr.10225 [source]

3462: Epithelial tumours of the lacrimal gland

ACTA OPHTHALMOLOGICA, Issue 2010
SE COUPLAND
Purpose To provide an overview of benign and malignant epithelial neoplasms arising in the lacrimal gland. Methods In the normal orbit, the lacrimal gland is clinically impalpable and is situated in the lacrimal fossa posterior to the superotemporal orbital rim. The gland is not truly encapsulated and is divided into the deep orbital and the superficial palpebral lobes by the levator aponeurosis. The retrospective study of 265 epithelial tumours of the lac¬rimal gland conducted by the Armed Forces Institute of Pa¬thology (AFIP) improved our understanding of the histologic classification and clinical behavior of epithelial tumours of the lacrimal gland. The historic works of Forrest (1954) and Zimmerman (1962) alleviated confu¬sion by applying to epithelial tumours of the lacrimal gland the histopathologic classification of salivary gland tumours. Epithelial tumours originating from the lacrimal gland should be staged according to the 7th Edition of the Tumor Node Metastasis (TNM) system, which is a modification of the World Health Organization (WHO) classification of salivary gland tumours. Results The most common benign epithelial tumour of the lacrimal gland is the pleomorphic adenoma. The most common lacrimal gland carcinomas include adenoid cystic carcinoma, "carcinoma ex pleomorphic adenoma", primary adenocarcinoma & mucoepidermoid carcinoma. The regional lymph nodes include: preauricular, submandibular and cervical lymph nodes. The lung is the most common metastatic site, followed by bone and remote viscera. Conclusion Subtyping & grading of lacrimal gland epithelial tumours requires the latest WHO/AFIP classifications. Staging of these tumours should follow the 7th TNM system. Collection of datapoints is essential to identify biomarkers, which includes only nuclear N23 and MIB-1 at present. [source]