Virchows Archiv

, Volume 459, Issue 1, pp 55–63

Differential clinicopathological features in microsatellite instability-positive colorectal cancers depending on CIMP status

  • Jeong Mo Bae
  • Mi Jung Kim
  • Jung Ho Kim
  • Jae Moon Koh
  • Nam-Yun Cho
  • Tae-You Kim
  • Gyeong Hoon Kang
Original Article

DOI: 10.1007/s00428-011-1080-3

Cite this article as:
Bae, J.M., Kim, M.J., Kim, J.H. et al. Virchows Arch (2011) 459: 55. doi:10.1007/s00428-011-1080-3

Abstract

Microsatellite instability-positive (MSI+) colorectal cancers (CRCs) are divided into CpG island methylator phenotype-positive (CIMP+) and CpG island methylator phenotype-negative (CIMP−) tumors. The repertoire of inactivated genes in CIMP+/MSI+ CRCs overlaps with but is likely to differ from that of CIMP−/MSI+ CRCs. Because epigenotypic differences are likely to be manifested as phenotypic differences, CIMP+/MSI+ CRCs are expected to differ from CIMP−/MSI+ CRCs in some clinicopathological features. This study aimed to characterize both common and different features between the two subtypes. A total of 72 MSI+ CRCs were analyzed for their methylation status in eight CIMP panel markers using MethyLight assay. CIMP+/MSI+ and CIMP−/MSI+ CRCs were compared regarding clinicopathologic features and mutation in KRAS/BRAF. An independent set of MSI+ CRCs (n = 97) was analyzed for their relationship of CIMP+ status with clinical outcome. Eighteen cases (25%) were CIMP+, and this CIMP+ subtype was highly correlated with older age (P < 0.001). Polypoid gross appearance without ulceration was observed only in CIMP−/MSI+ CRCs (18.5%, P = 0.057). CIMP+/MSI+ CRCs were closely associated with poor differentiation, medullary appearance, signet ring cell appearance, and acinar-form appearance, whereas the CIMP−/MSI+ subtype was closely associated with intraglandular eosinophilic mucin and stratified nuclei (all P values <0.05). Patients with CIMP+/MSI+ CRCs showed worse overall survival than patients with CIMP−/MSI+ CRCs. Our results demonstrate heterogeneity in the clinicopathological features of MSI+ CRCs depending on CIMP status. The observation that CIMP+ and CIMP− subtypes showed different clinical behaviors may provide a clue for establishing subtype-specific therapeutic strategies for these two subtypes.

Keywords

Colon cancerCpG islandDNA methylationMicrosatellite instabilityPrognosis

Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Jeong Mo Bae
    • 1
  • Mi Jung Kim
    • 2
  • Jung Ho Kim
    • 1
  • Jae Moon Koh
    • 1
  • Nam-Yun Cho
    • 3
  • Tae-You Kim
    • 4
  • Gyeong Hoon Kang
    • 1
    • 3
  1. 1.Department of PathologySeoul National University College of MedicineSeoulSouth Korea
  2. 2.Department of Diagnostic PathologyAsan Medical CenterSeoulSouth Korea
  3. 3.Laboratory of Epigenetics, Cancer Research Institute and 2nd Stage Brain KoreaSeoul National University College of MedicineSeoulSouth Korea
  4. 4.Department of Internal MedicineSeoul National University College of MedicineSeoulSouth Korea