Stanford School of Medicine

Surgical Pathology Criteria
http://surgpathcriteria.stanford.edu/

 use browser back button to return

Undifferentiated Carcinoma of the Colon and Rectum

Definition

  • Undifferentiated carcinoma not otherwise specified, arising in the colon or rectum

Note:

Diagnostic Criteria

  • No gland formation (<5% by definition)
    • Solid sheets, nests and trabeculae
  • Pleomorphic large cells
    • Nuclei variable, may be vesicular
      • Nucleoli variable
    • High nuclear/cytoplasmic ratio
      • Scant to moderate cytoplasm
  • Infiltrative border
  • No intracytoplasmic mucin or expression of chromogranin or synaptophysin
  • Generally poor prognosis

Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342

Original posting/updates : 1/31/10, 11/12/11

Differential Diagnosis

Colorectal Medullary Carcinoma Colorectal Undifferentiated Carcinoma NOS
Lacks any gland formation May have <5% gland formation
Uniform small to medium sized nuclei Pleomorphic large nuclei
Uniformly prominent nucleoli Variable nucleoli
Pushing border Infiltrative border
Prominent lymphoid infiltrate in virtually all cases Lymphoid infiltrate variable

Colorectal Undifferentiated Carcinoma NOS Colorectal Small Cell Neuroendocrine (Undifferentiated) Carcinoma
Chromogranin and synaptophysin at most focal or scattered Chromogranin or synaptophysin may be negative or positive
Vesicular nuclei Chromatin finely granular, stippled
Prominent nucleoli Inconspicuous nucleoli
Pleomorphic large cells Uniform small to medium size cells

Colorectal Undifferentiated Carcinoma NOS Colorectal Large Cell Neuroendocrine Carcinoma
Chromogranin and synaptophysin at most focal or scattered Chromogranin or synaptophysin must be positive in at least 20-50% of cells
Vesicular nuclei Chromatin finely granular, stippled
Prominent nucleoli Inconspicuous nucleoli
Does not form rosettes May form rosettes

Grading / Staging

Grading

  • Grade is based on MSI status
    • MSI-H carcinomas are low grade
    • MSS or MSI-L carcinomas are high grade

Staging

Bibliography

  • Bosman FT, Carneiro F, Hruban RH, Thiese ND (Eds). WHO Classifiication of Tumors of the Digestive System, IARC, Lyon 2010
  • Jessurun J, Romero-Guadarrama M, Manivel JC. Medullary adenocarcinoma of the colon: clinicopathologic study of 11 cases. Hum Pathol. 1999 Jul;30(7):843-8.
  • Wick MR, Vitsky JL, Ritter JH, Swanson PE, Mills SE. Sporadic medullary carcinoma of the colon: a clinicopathologic comparison with nonhereditary poorly differentiated enteric-type adenocarcinoma and neuroendocrine colorectal carcinoma. Am J Clin Pathol. 2005 Jan;123(1):56-65.
  • Winn B, Tavares R, Fanion J, Noble L, Gao J, Sabo E, Resnick MB. Differentiating the undifferentiated: immunohistochemical profile of medullary carcinoma of the colon with an emphasis on intestinal differentiation. Hum Pathol. 2008 Nov 6. [Epub ahead of print]
  • Rüschoff J, Dietmaier W, Lüttges J, Seitz G, Bocker T, Zirngibl H, Schlegel J, Schackert HK, Jauch KW, Hofstaedter F. Poorly differentiated colonic adenocarcinoma, medullary type: clinical, phenotypic, and molecular characteristics. Am J Pathol. 1997 May;150(5):1815-25.
  • Sugao Y, Yao T, Kubo C, Tsuneyoshi M. Improved prognosis of solid-type poorly differentiated colorectal adenocarcinoma: a clinicopathological and immunohistochemical study. Histopathology. 1997 Aug;31(2):123-33.
  • Hinoi T, Tani M, Lucas PC, Caca K, Dunn RL, Macri E, Loda M, Appelman HD, Cho KR, Fearon ER. Loss of CDX2 expression and microsatellite instability are prominent features of large cell minimally differentiated carcinomas of the colon. Am J Pathol. 2001 Dec;159(6):2239-48.
Printed from Surgical Pathology Criteria: http://surgpathcriteria.stanford.edu/
© 2009  Stanford University School of Medicine