A DISCUSSION of the microscopic grading of cancer1 and its practical application will be made from the viewpoint of the practice of this procedure. A brief history2 of the idea would be in order. Virchow in 1858 postulated that there were differences in malignancy of tumors in the matter only of degree. Hansemann spent many years studying the histology of cancer, beginning in 1890, elaborating on the earlier work of Pfitzner, Klebs and Arnold. The conclusions and observations of Hansemann form the basis on which Broders applied the grading of cancer to clinical work, announced3 in 1920. However, Broders came to his conclusions independently4 and many years after Hansemann's work was forgotten and relegated to the shelf of academic curiosity. Also, in 1912, Schottlander and Kermauner endeavored to apply Hansemann's principles, but failed to think them of clinical significance. Solomon, in 1913, in his studies of