Evidence-based pathology and the pathologic evaluation of thymomas: The world health organization classification can be simplified into only 3 categories other than thymic carcinoma Journal Article


Authors: Marchevsky, A. M.; Gupta, R.; McKenna, R. J.; Wick, M.; Moran, C.; Zakowski, M. F.; Suster, S.
Article Title: Evidence-based pathology and the pathologic evaluation of thymomas: The world health organization classification can be simplified into only 3 categories other than thymic carcinoma
Abstract: BACKGROUND. The clinical validity and applicability of the World Health Organization (WHO) histopathologic classification of thymomas ('classification') has been questioned. Evidence-based pathology promotes the use of systematic reviews and analysis of data with meta-analysis rather than subjective reviews of the literature. METHODS. The authors performed a review of the English literature from 1999 to the present to identify 'best evidence' regarding the use of the 'classification.' The data were analyzed with meta-analysis software. RESULTS. To the authors' knowledge, only Level-3 or -4 evidence published in retrospective cases series is currently available regarding the use of the 'classification.' Meta-analysis demonstrated that only 3 WHO categories of thymomas are associated with significant survival differences: A/AB/B1, B2, and B3. It also indicated significant heterogeneity with regard to the results published in different studies. To the authors' knowledge there is no current evidence to determine whether thymoma types are significant prognostic features for patients previously stratified by stage. CONCLUSIONS. There is a lack of randomized clinical trials evaluating the prognosis of patients with thymomas and the effects of various treatment modalities. The WHO classification of thymomas needs revision and could most likely be simplified into fewer classes with significant prognostic value. Future studies are needed to evaluate the prognostic and/or predictive value for thymoma patients previously stratified by stage. The latter information is important to help select those patients who may benefit from neoadjuvant chemotherapy or postoperative radiotherapy and other modalities. ©2008 American Cancer Society.
Keywords: cancer survival; review; cancer staging; neoplasm staging; evidence based medicine; evidence-based medicine; classification; evidence based practice; pathology; chemistry; systematic review; clinical evaluation; world health organization; cancer classification; thymoma; thymus neoplasms; meta analysis; prognostic value; randomized clinical trials; world health organization classification
Journal Title: Cancer
Volume: 112
Issue: 12
ISSN: 0008-543X
Publisher: Wiley Blackwell  
Date Published: 2008-06-15
Start Page: 2780
End Page: 2788
Language: English
DOI: 10.1002/cncr.23492
PUBMED: 18442102
PROVIDER: scopus
DOI/URL:
Notes: --- - "Cited By (since 1996): 24" - "Export Date: 17 November 2011" - "CODEN: CANCA" - "Source: Scopus"
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MSK Authors
  1. Maureen F Zakowski
    275 Zakowski