the grade of a cancer tells how abnormal its cells (or patterns of cells) look under the microscope. There are different grading systems for different types of cancers. Grading is done by a pathologist who looks at sample tissue from the biopsy. Cancers with higher grades (more abnormal-looking cells or patterns) tend to grow and spread more quickly and have a worse prognosis (outlook). See also biopsy, pathologist, staging.