LNSLNS

We thank our correspondent for his contribution and for the opportunity to discuss the term intraepithelial neoplasia again, against the background of the correctly stated and therefore required transparency between endoscopy and pathology. In contradiction to the opinion expressed by Dr Haroske, it is the new WHO classification that dictates the appropriate use of the terms.

The term “intraepithelial neoplasia” is used for lesions with certain cytological and architectural characteristics that reflect the underlying molecular changes. However, the reverse is not necessarily true: such molecular changes do not necessarily result in changes that are visible on histology or cytology—which underlines the precursor character of colorectal adenomas, for example. For this reasons the term intraepithelial neoplasia is more widely defined and includes all possibilities: precursor lesions with “dysplasias” or without “atypias” (for example the sessile serrated adenoma [SSA]). The malignant potential is the one factor that all intraepithelial neoplasias have in common (1).

We have to contradict Dr Haroske where the term dysplasia is concerned. The WHO classification defines unequivocally that dysplasias are histologically defined as “unequivocal neoplastic epithelium without evidence of tissue invasion”. Even though as pathologists we sometimes appreciate creative freedom, we cannot ignore the international definitions. The monitoring strategies that were mentioned are clearly defined in the S3 guideline “colorectal carcinoma,” which was substantially developed by pathologists (the authors, among others). The different entities are discussed and acknowledged there (2).

DOI: 10.3238/arztebl.2010.0116b

Prof. Dr. med. Andrea Tannapfel
Institut für Pathologie
Ruhr-Universität Bochum am BG-Universitätsklinikum Bergmannsheil
Deutsches Mesotheliomregister
Bürkle-de-la-Camp Platz 1, 44789 Bochum, Germany
andrea.tannapfel@rub.de

Conflict of interest statement
The author has received honoraria for speaking and advisory activities as well as travel expenses and research support from Falk, Pfizer, Sanofi, Roche, Astra-Zeneca, Lilly, Novartis, Merck, and Amgen.

1.
WHO classification of tumours of the digestive system. WHO – IARC Press, Lyon 2010.
2.
Schmiegel W, Pox C, Arnold D, Porschen R, Rödel C, Reinacher-Schick A: Clinical practice guideline: colorectal carcinoma: the management of polyps, (neo)adjuvant therapy, and the treatment of metastases. Dtsch Arztebl Int 2009;106(51–52): 843–8. VOLLTEXT
3.
Tannapfel A, Neid M, Aust D, Baretton G: The origins of colorectal carcinoma: specific nomenclature for different pathways and precursor lesions. Dtsch Arztebl Int 2010; 107(43): 760–6. VOLLTEXT
1.WHO classification of tumours of the digestive system. WHO – IARC Press, Lyon 2010.
2.Schmiegel W, Pox C, Arnold D, Porschen R, Rödel C, Reinacher-Schick A: Clinical practice guideline: colorectal carcinoma: the management of polyps, (neo)adjuvant therapy, and the treatment of metastases. Dtsch Arztebl Int 2009;106(51–52): 843–8. VOLLTEXT
3.Tannapfel A, Neid M, Aust D, Baretton G: The origins of colorectal carcinoma: specific nomenclature for different pathways and precursor lesions. Dtsch Arztebl Int 2010; 107(43): 760–6. VOLLTEXT