@misc{Klimkowska_Agnieszka_Low-level_2010,
 author={Klimkowska, Agnieszka},
 address={Kraków},
 howpublished={online},
 year={2010},
 school={Wydział Lekarski},
 language={pol},
 abstract={INTRODUCTION: Microsatellite-unstable tumors can be divided into two distinct phenotypes: MSI- high (MSI-H) and MSI-low (MSI-L). About 15% of colorectal cancers exhibit MSI-H. Such types are usually right-sided, have a mucinous histology, poor differentiation, less frequency of metastasis and better prognosis. Clinicopathological features of MSI-L cancers are not well defined and its significance remains controversial. However, recent studies support that MSI-L may form a separate entity differing both from MSI-H and MSS tumors. MATERIAL/METHODS: A total of 163 cases with colorectal cancers were assessed for MSI status. Three groups - MSS (n=133), MSI-L (n=15), MSI-H (n=15) - were compared with respect to stage disease progression, features of angioinvasion and histological grade. Immunohistochemistry of Bcl-2, Cdx2, Ki-67, MLH1, MSH2, MSH6, pl 6 and p53 was analyzed on 108 cases of the disease. RESULTS: In comparison to MSS cancers, the MSI-L had larger tumor size, mucinous histology and weak expression of MSH6. They had a higher p53 LOH number and were almost only left-sided contrasting with MSI-H and MSS tumors. More frequent metastasis and higher TNM stage as compared with MSI-H tumors indicates for peculiar, worse pathologic behavior of MSI-L tumors The MSI-H cancers were significantly larger, more frequently right-sided, poorly differentiated and had mucinous histolog},
 abstract={y. They demonstrated less frequently blood vessels angioinvasion, loss of expression for MLH1 and no distant metastases. Inverse relationship between MSI-H and Ki-67 expression was noted.},
 title={Low-level instability of microsatellite DNA in sporadic colorectal cancers},
 type={Praca doktorska},
 keywords={MSI-L, colorectal cancer, microsatellite instability},
}