Search results
Results from the WOW.Com Content Network
To be assigned a status of PR or CR, changes in tumor measurements must be confirmed by repeat assessments that should be performed no less than 4 weeks after the criteria for response are first met. Longer intervals as determined by the study protocol may also be appropriate.
The TNM Classification of Malignant Tumors (TNM) is a globally recognised standard for classifying the anatomical extent of the spread of malignant tumours (cancer). It has gained wide international acceptance for many solid tumor cancers, but is not applicable to leukaemia or tumors of the central nervous system .
Cancer staging can be divided into a clinical stage and a pathologic stage. In the TNM (Tumor, Node, Metastasis) system, clinical stage and pathologic stage are denoted by a small "c" or "p" before the stage (e.g., cT3N1M0 or pT2N0). This staging system is used for most forms of cancer, except brain tumors and hematological malignancies.
Grading in cancer is distinguished from staging, which is a measure of the extent to which the cancer has spread. Pathology grading systems classify the microscopic cell appearance abnormality and deviations in their rate of growth with the goal of predicting developments at tissue level (see also the 4 major histological changes in dysplasia ).
The WHO Criteria, developed in the 1970s by the International Union Against Cancer and the World Health Organization, represented the first generally agreed specific criteria for the codification of tumor response evaluation. These criteria were first published in 1981. [2] The RECIST criteria, first published in 2000, [3] revised the WHO ...
For example, if the primary tumor grade was 2 and the secondary tumor grade was 3 but some cells were found to be grade 4, the Gleason score would be 2+4=6. This is a slight change from the pre-2005 Gleason system where the second number was the secondary grade (i.e., the grade of the second-most common cell line pattern). [4]
The concept of grading of the tumors of the central nervous system, agreeing for such the regulation of the "progressiveness" of these neoplasias (from benign and localized tumors to malignant and infiltrating tumors), dates back to 1926 and was introduced by P. Bailey and H. Cushing, [1] in the elaboration of what turned out the first systematic classification of gliomas.
In general, greater tumor size and presence of lymph node metastasis predicts higher risk of recurrence after initial diagnosis and treatment. In one study, the lifetime risk of recurrence was 20% for smaller (<2 cm) tumors without lymph node metastasis. Larger tumors without lymph nodes had 38% risk of recurrence.