Prognostic typing in breast cancer.

Infiltrating breast carcinomas in which recurrence takes place 10 years or more after operation are reported to contain tumour cells of characteristic morphology. The cytological features of these tumour cells form the basis of the system of classification described here. Three cytological types are recognized, prognosis being best in type III. Typing is carried out on specimens stained with haematoxylin and eosin. The results of typing were reproducible in over 90% of cases and independent of the histology of the lesion. Correlation to survival time was shown in a total of 222 cases.