Grading (tumors)

The term grading (English to grade, classify, arrange them in a hierarchy ' ) is used in connection with the assessment of a tumor to indicate the degree of differentiation of the cancer tissue, that is, the extent to which it deviates from the normal tissues. This important information for prognosis and therapy is provided by the pathologist examining a tissue sample (such as a biopsy) under a microscope.

The UICC ( Union Internationale Contre le Cancer ) divides cancer cells in grade 1, 2, 3, sometimes 4 and 9 ( other degrees there is not).

  • Grade 1 ( G1): well- differentiated malignant tissue ("low -grade" ), high consistency with the tissue of origin
  • Grade 2 ( G2): moderately differentiated malignant tissue
  • Grade 3 (G3 ): bad / poorly differentiated malignant tissue
  • Grade 4 (G4): undifferentiated malignant tissue ( undifferentiated or anaplastic ) ( "high-grade "). The tumor may sometimes be associated with a particular tissue of origin no longer or only on the basis of immunohistochemical studies.
  • Grade 9 ( G9): Grade of differentiation can not be assessed.

Normally show highly differentiated tumors ( G1) a much more favorable course than anaplastic tissue ( G4). Important parameters here are determining the size and shape of cell nuclei of cells whose division activity, and the similarity with the tissue of origin. However, specific criteria have been identified for most tumors. From tumor size alone their aggressiveness can not be inferred and UICC TNM classification system alone are not very suitable.

Grading of brain tumors

→ Main article: WHO classification of tumors of the central nervous system

Grading of prostate tumors

→ Main article: Grading of prostate tumors

Mettmach WHO classification of the tumors of the central nervous system Gleason Grading System
239695
de