POLIPI e POLIPOSI INTESTINALI Alterazione maturativa amartomatosa infiammatoria displastica Non Neoplastici Neoplastici Singoli o piccolo numero Multipli Polipo iperplastico Polipo giovanile Polipo di Peutz-Jegher Polipo infiammatorio Adenoma Adenoma serrato Poliposi giovanile Sindrome di Peutz-Jegher Sindrome di Gardner Sindrome di Turcot amartomatosa displastica CLASSIFICAZIONE ISTOLOGICA Poliposi adenomatosa familiare Poliposi Iperplastica
POLIPI e POLIPOSI INTESTINALI Alterazione maturativa amartomatosa infiammatoria displastica Non Neoplastici Neoplastici Singoli o piccolo numero Multipli Polipo iperplastico Polipo giovanile Polipo di Peutz-Jegher Polipo infiammatorio Adenoma Adenoma serrato Poliposi giovanile Sindrome di Peutz-Jegher Sindrome di Gardner Sindrome di Turcot amartomatosa displastica CLASSIFICAZIONE ISTOLOGICA Poliposi adenomatosa familiare Poliposi Iperplastica
POLIPI e POLIPOSI INTESTINALI A precancerous condition is a clinical state associated with
a significantly increased risk of cancer.
A precancerous lesion is a histopathological abnormality
in which a cancer is more likely to occur than in its
apparently normal counterpart.
The term precancerous does not imply the inevitability of
developing a malignant lesion. It is rather a marker of an
increased probability or risk of malignant change.
B.C. Morson I980
POLIPI e POLIPOSI INTESTINALI Lesion thought to be associated with an increased cancer
risk for the individual patient exibit an epithelial
alteration known as dysplasia.
The risk of cancer developing depends on the grade or
severity of the dysplasia: mild, moderate, severe.
B.C. Morson I980
U.S.A. Dysplasia: low grade, high grade.
POLIPI e POLIPOSI INTESTINALI All adenomas are dysplastic,but not all dysplastic
epithelium is polypoid i.e. flat adenoma.
Dysplasia may occur in flat mucosa in such conditions
as ulcerative colitis and Crohn disease.
POLIPI e POLIPOSI INTESTINALI The concept of the adenoma-carcinoma sequence has been
superseded by the dysplasia-carcinoma sequence.
The magnitude of the risk of malignant change appears to
be closely related to the grade of dysplasia.
POLIPI e POLIPOSI INTESTINALI Aberrant crypt foci - ACF -
is the earliest morphological precursor of epithelial neoplasia.
Progession from ACF through adenoma to carcinoma
characterizes carcinogenesis in the large intestin.
Microscopy shows crypt of enlarged calibre and thickened dysplastic epithelium with reduced mucin content.
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